Principles of bearing selection and application
8
Angular contact ball bearings
112
Cylindrical roller bearings 180
Double direction angular contact thrust ball bearings
214
Single direction angular contact thrust ball bearings 234
Locking devices 260 Copyright SKF 2003 The contents of this publication are the copyright of the publisher and may not be reproduced (even extracts) unless permission is granted. Every care has been taken to ensure the accuracy of the information contained in this publication but no liability can be accepted for any loss or damage, whether direct, indirect or consequential arising out of the use of the information contained herein. www.skf.com Publication 5002 E 2003 - 02
Gauges 286
Other products and services 298
Products index 301
The SKF Group – a worldwide corporation SKF is an international industrial Group operating in more than 130 countries and is world leader in bearings. The company was founded in 1907 following the invention of the self-aligning ball bearing by Sven Wingquist and, after only a few years, SKF began to expand all over the world. Today, SKF has some 40 000 employees and around 80 manufacturing facilities spread throughout the world. An international sales network includes a large number of sales companies and some 7 000 distributors. Worldwide availability of SKF products is supported by a comprehensive technical advisory service. The key to success has been a consistent emphasis on maintaining the highest quality of its products and services. Continuous investment in research and development has also played a vital role, resulting in many examples of epoch-making innovations.
The business of the Group consists of bearings, seals, special steels and a comprehensive range of other high-tech industrial components. The experience gained in these various fields provides SKF with the essential knowledge and expertise required in order to provide the customers with the most advanced engineering products and efficient service.
The SKF Group is the first major bearing manufacturer to have been granted approval according to ISO 14001, the international standard for environmental management systems. The certificate is the most comprehensive of its kind and covers more than 60 SKF production units in 17 countries.
The SKF Engineering & Research Centre is situated just outside Utrecht in The Netherlands. In an area of 17 000 square metres (185 000 sq.ft) some 150 scientists, engineers and support staff are engaged in the further improvement of bearing performance. They are developing technologies aimed at achieving better materials, better designs, better lubricants and better seals – together leading to an even better understanding of the operation of a bearing in its application. This is also where the SKF Life Theory was evolved, enabling the design of bearings that are even more compact and offer even longer operational life.
SKF has developed the Channel concept in factories all over the world. This drastically reduces the lead-time from raw material to end product as well as work in progress and finished goods in stock. The concept enables faster and smoother information flow, eliminates bottlenecks and bypasses unnecessary steps in production. The Channel team members have the knowledge and commitment needed to share the responsibility for fulfilling objectives in areas such as quality, delivery time, production flow etc.
SKF manufactures ball bearings, roller bearings and plain bearings. The smallest are just a few millimetres (a fraction of an inch) in diameter, the largest several metres. SKF also manufactures bearing and oil seals that prevent dirt from entering and lubricant from leaking out. SKF’s subsidiaries CR and RFT S.p.A. are among the world’s largest producers of seals.
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Foreword Wherever there is rotation, there is a need for some form of bearing. The function of a rolling bearing is to reduce or eliminate the friction between a fixed and a moving surface and to carry a load. The life of a rolling bearing must be compatible with the life of the application in which it is mounted. The SKF standard product range comprises more than 22 000 variants, covering all the principal bearing types. Made by SKF stands for excellence. It symbolises our consistent endeavour to achieve total quality in everything we do. For those who use our products, “Made by SKF” implies three main benefits. Reliability – thanks to modern, efficient products, based on our worldwide application know-how, optimised materials, forward-looking designs and the most advanced production techniques. Cost effectiveness – resulting from the favourable ratio between our product quality plus service facilities, and the purchase price of the product. Market lead – which you can achieve by taking advantage of our products and services. Increased operating time and reduced downtime, as well as improved output and product quality are the key to a successful partnership.
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Machine tool applications require superior performance from the bearings used to support spindles and precision ball screws. They must exhibit this in terms of speed capability, system temperature stability, rigidity, accuracy and noise level; such characteristics are rarely met by bearings for general-purpose applications. Therefore, SKF produces special high-precision bearings designed to satisfy the most demanding requirements in the machine tool environment. This catalogue presents the current range of SKF high-precision bearings and related products. The data in this catalogue are based on current production. However, design refinement for continuous improvement in either manufacturing or performance may result in changes. The basic load ratings have been calculated in accordance with the latest specifications. Earlier catalogues, in which the data varies from that given here, are rendered invalid. SKF reserves the right to make changes necessitated by technological developments. In accordance with ISO (International Standards Organisation) Standard 1000: 1992, SI units (Système International d’Unités) are used in this catalogue.
the more important it is to make use of SKF know-how in the manufacture and application of high-precision rolling bearings. Where to find information The bearing tables and technical data on the following pages provide information for bearing selection and application design. More details on bearing technology and on other related products can be found in specific publications, the SKF General Catalogue or the SKF Interactive Engineering Catalogue, available as a CD-ROM or online under www.skf.com. This site also contains further information on the SKF Group, its products, services and contacts.
Almost 100 years of worldwide experience For almost 100 years SKF has held a leading position in all major industrial fields where rolling bearings are used. SKF not only supplies a wide range of bearings but also has broad experience in application engineering, and is at the forefront of systems design. This background comes from the partnerships developed over the years with leading firms in the machine tool industry. The more complex the problems, 5
Principles of bearing selection and application Contents
1
Selection of bearing types A wide range of high-precision bearings Bearings materials Accuracy Rigidity Speed Available space Loads
8 8 9 10 12 12 13 14
Load carrying capacity and life General Rating lives Rating life equation for hybrid bearings Load carrying capacity of bearing sets Equivalent bearing loads
17 17 17 18 19 19
Rigidity System rigidity Influence of a loose fit
21 21 22
Speed Rotational speed Speed ratings Speed capability of bearing systems
23 23 25 26
Bearing data – general Dimension Tolerances Bearing internal clearance or preload Material for high-precision bearings
27 27 28 30 31
Application of bearings Bearing arrangements Radial location of bearings Application examples Axial location of bearings Bearing preload Seals
34 34 35 36 51 52 57
Lubrication and maintenance General Grease lubrication Oil lubrication Maintenance
62 62 62 71 78
Dismounting and mounting Dismounting Mounting Inspection
79 79 89 105 7
1 Principles of bearing selection and application
Selection of bearing type A wide range of high-precision bearings It is not always possible to find an appropriate solution to application design and problems using standard bearings for general machinery. This is particularly true in machine tool applications where requirements are tougher. SKF has developed a very comprehensive range of high-precision bearings for machine tool spindles, and other applications where high demands are placed on accuracy and speed capability. Each of these bearing types has specific features that make it particularly suitable for specific applications. Internal design is state-of-the art, and differs in many ways from that of a standard bearing. The design has been optimised for outstanding speed capability in combination with the highest possible stiffness. When designing a bearing arrangement it is necessary to consider a number of factors, i.e.: ● Accuracy ● Available space ● Load ● Required system rigidity ● Accommodation of axial displacements ● Speed ● Heat generation.
8
Depending on the application, one or more of these factors will have a dominant influence. It is therefore, not possible to set down general rules for the selection of bearing type or bearing series. Where demands for high-precision and productivity are exceptionally high, SKF provides a comprehensive range of hybrid (i.e. bearings with steel rings and ceramic rolling elements) high-precision angular contact ball bearings and cylindrical roller bearings for machine tool spindles. To make bearing selection easier, the properties of the different bearing types are described in the following.
Bearing materials All-steel bearings The performance and reliability of rolling bearings are determined to a large degree by the materials from which the bearing components are made. Steels used for high-precision bearing rings and rolling elements are capable of being adequately hardened and have high fatigue strength and wear resistance. Moreover they have the structural and dimensional stability to satisfy the spindle operating temperatures. SKF high-precision bearing rings and rolling elements are generally made of through-hardened carbon chromium steel containing approximately 1 % carbon and 1,5 % chromium.
Hybrid bearings Machine tools, especially machining centres, can have higher machining efficiencies and higher machining accuracies when operated at higher speeds. For this reason, there have been ever-greater demands for higher speed performance of their spindle bearings. If the performance required is close to all-steel bearing limits, or if higher rigidity or longer life are needed, hybrid highprecision bearings can be used. Hybrid high-precision bearings consist of outer and inner rings made of bearing steel and ceramic (silicon nitride Si3N4) rolling elements, having density as light as 40 % of bearing steel but yet having a high rigidity (➔ fig 1 ).
Comparison of performance and cost for different bearing design (material) Fig
Bearing material
Performances
Cost
1
Typical applications
Full steel
Machine tools. Precision equipments. High speed rolling mills. High speed electric motors, etc.
Hybrids
Machine tools. Precision equipments. Turbochargers. High speed electric motors, etc.
9
1
1 Principles of bearing selection and application
Accuracy Running accuracy The running accuracy of a bearing arrangement is governed by the accuracy of all the component parts of the arrangement. Where bearings are concerned, this is primarily determined by the accuracy of form and position of the raceways on the bearing rings. When selecting the appropriate tolerance class for a particular bearing, the maximum radial runout of the inner ring (Kia) is usually the determining factor for most applications. To facilitate comparison, Diagram 1 gives relative values of the radial runout
for the different tolerance classes comparing bearings with bore diameters. The different standards ABMA and ISO are also compared in Table 1 . Most SKF precision bearings are manufactured to tolerance class P4A, P4C, and SP. P4A is the standard tolerance class for angular contact ball bearings; SP the standard for cylindrical roller bearings and double direction angular contact thrust ball bearings, and P4C the standard class for single direction angular contact thrust ball bearings of the BTM series. For bearing arrangements where this standard precision is inadequate, angular contact ball bearings made to tolerance class PA9A, and cylindrical roller bearings and double direction
angular contact thrust ball bearings made to tolerance class UP specifications can be supplied (➔ Table 2 ). Normally, the maximum values of Kia given in the table are much higher than the actual values. This means for example, that if bearings with class SP tolerances are used, depending on the bearing size and whether bearings are properly mounted, a running accuracy of less than 2 µm can be achieved.
Dimensional accuracy The dimensional accuracy of a bearing is important with respect to the fit between bearing ring and shaft or housing. As the fit influences the clearance or preload of mounted bearings, the tolerances for the bearing and its seating lie within narrow limits. Where cylindrical roller bearings with a tapered bore are concerned, slightly larger dimensional deviations are permissible than for example, angular contact ball bearings with similar running accuracy. This is because the clearance or preload of the bearing is determined by driving up the inner ring on its tapered seating.
Comparison of different standards
SKF tolerance classes for high-precision bearings
Comparison of accuracy of different tolerance classes Diagram
1
Inner ring radial runout factor
100
100
80
Table
60
60
40
Table
1
ABMA Tolerance class
ISO Tolerance class
SKF Standard
SKF Tolerance Class
Boundary dimensions ISO, ABMA
Running accuracy ISO, ABMA
ABEC 9
2
PA9A
SP
ISO 5, ABEC 5
ISO 4, ABEC 7
ABEC 7
4
P4
UP
ISO 4, ABEC 7
ISO 2, ABEC 9
ABEC 5
5
P5
P4A
ISO 4, ABEC 7
ISO 2, ABEC 91)
P4C
ISO 4, ABEC 7
ISO 4, ABEC 7
PA9A
ISO 2, ABEC 9
ISO 2, ABEC 9
2
30 20
20
10
8
0 Normal
P6
P5
P4, SP, P4C
P4A, PA9A
UP Tolerance class
1)
10
Up to 120 mm bore diameter, for larger sizes, ABEC 7 or better
11
1
1 Principles of bearing selection and application
Rigidity
Speed
Available space
The rigidity of a spindle/bearing system is of particular importance in machine tool applications as the magnitude of the deflection under load determines the productivity and machining accuracy of a machine tool. Bearing stiffness influences the stiffness of a bearing arrangement and thus the stiffness of the complete spindle/bearing system. However, bearings alone cannot be the only reason for high or low rigidity: when checking the behaviour of a complete system, bending of the spindle itself, position and number of support bearings and tool overhang may also have a great influence. The stiffness of a bearing depends on its type and size, the most important criteria being: ● type of rolling elements (rollers or balls) ● number and size of the rolling elements, and ● contact angle.
There is a limit to the speed at which rolling bearings can be operated. Generally, it is the permitted operating temperature with respect to the lubricant being used, or to the material of the bearing components that sets the limit. The speed at which this limiting bearing temperature is reached depends on the frictional heat generated in the bearing (including any externally applied heat) and the amount of heat that can be transported away from the bearing. Bearing type and size, internal design, load, lubrication and cooling conditions, as well as cage design, accuracy and internal clearance/preload, all play a part in determining speed capability.
High-precision bearing arrangements generally call for bearings with a low crosssection because of the space available, together with the high requirements in respect of stiffness and running accuracy of the arrangement. These bearings generally have a large number of rolling elements and consequently a high stiffness. They also enable relatively large diameter spindles to be used for a given housing bore diameter, and therefore exhibit all the advantages important for the stiffness and running accuracy of a bearing arrangement, e.g. a spindle bearing arrangement. Almost all of the angular contact ball bearings, cylindrical roller bearings and angular contact thrust ball bearings used
Because of the much larger contact area between rolling elements and raceways in a roller bearing than in a ball bearing, roller bearing stiffness is much higher than ball bearing stiffness. The number of rolling elements has a greater influence on bearing stiffness, than the size of the rolling elements. Because of this, highprecision bearings almost always have the dimensions of the light Diameter Series 0 or 9. Where high radial stiffness is required, bearings having the smallest possible contact angle should be used. Conversely, where high axial stiffness is called for, the contact angle should be as large as possible.
for machine tool applications belong to the ISO Diameter Series 9 and 0. By selecting suitable combinations of bearings it is thus possible to achieve an optimum bearing arrangement for specific requirements within the same radial space. For bearing arrangements where less radial space is available, angular contact ball bearings and cylindrical roller bearings belonging to ISO Diameter Series 9 can be used. Angular contact ball bearings to the ISO Diameter Series 2, despite being rarely chosen for new designs, are still common in existing applications. To illustrate the space required, fig 2 shows cross-sections of the most common machine tool spindle bearings belonging to the different Diameter Series.
High-precision bearings cross section for different Diameter Series Fig
2
Bearings with steel rolling elements 9
0
9
0
2
9
0
0
0
0
Bearings with ceramic rolling elements
12
2
0
0
0
13
1
1 Principles of bearing selection and application
Loads
Table
In machine tools – the main application for high-precision bearings – the load carrying capacity of a bearing is usually of much less importance when determining bearing size, than in engineering applications in general. Other criteria such as stiffness, size of the requisite bore in the spindle, machining speeds and accuracy are the decisive factors. When selecting the bearing type for a given bearing arrangement, however, the magnitude and direction of action of the load play an important part. As a general rule, roller bearings can carry heavier loads than ball bearings having the same boundary dimensions (➔ Table 3 ).
Diametric Series ISO SKF Series designation
Bearing Code
Contact angle α
Shaft diameters from up to and incl.
Loading
Precision SKF tolerance Class
Speed rating n dm
–
–
–
deg
mm
mm
–
–
106 mm/min
9
719 ACX 719 ACD 719 ACE 719 CX 719 CD 719 CE 719 ACX/HC
A A A A A A Hybrid A
25 25 25 15 15 15 25
10 35 20 10 10 20 10
30 220 120 30 220 120 30
combined combined combined combined combined combined combined
P4A P4A P4A P4A P4A P4A P4A
1,5 1,5 2,2 1,8 1,8 2,4 1,8
719 ACD/HC 719 ACE/HC 719 CX/HC 719 CD/HC 719 CE/HC NNU 49 B/W33 NNU 49 BK/W33
Hybrid A Hybrid A Hybrid A Hybrid A Hybrid A C2 C2
25 25 15 15 15 0 0
35 20 10 35 20 100 100
140 120 30 140 120 240 240
combined combined combined combined combined radial only radial only
P4A P4A P4A P4A P4A SP SP
1,8 2,5 2,1 2,1 2,8 0,8 0,8
70 ACX 70 ACD 70 ACE 70 CX 70 CD 70 CE 70 ACX/HC
A A A A A A Hybrid A
25 25 25 15 15 15 25
10 35 20 8 35 20 10
30 240 100 30 240 100 30
combined combined combined combined combined combined combined
P4A P4A P4A P4A P4A P4A P4A
1,5 1,5 2,2 1,8 1,8 2,4 1,8
70 ACD/HC 70 ACE/HC 70 CX/HC 70 CD/HC 70 CE/HC N 10 KTN(9) N 10 KTNHA
Hybrid A Hybrid A Hybrid A Hybrid A Hybrid A C1 C1
25 25 15 15 15 0 0
35 20 8 35 20 40 40
100 100 30 100 100 120 120
combined combined combined combined combined radial only radial only
P4A P4A P4A P4A P4A SP SP
1,8 2,5 2,1 2,1 2,8 1 1,8
N 10 KTN(9)/HC N 10 KTNHA/HC NN 30 NN 30 K 2344(00) B BTM – A BTM – B
Hybrid C1 Hybrid C1 C2 C2 AT2 AT2 AT2
0 0 0 0 60 30 40
40 40 25 25 35 60 60
120 120 130 280 200 130 130
radial only radial only radial only radial only thrust only thrust only thrust only
SP SP SP SP SP P4C P4C
1,15 2 0,8 0,8 0,7 1,05 0,9
2
72 ACX 72 ACD 72 CX 72 CD 72 ACX/HC 72 ACD/HC 72 CX/HC 72 CD/HC BSA 2
A A A A Hybrid A Hybrid A Hybrid A Hybrid A AT1
25 25 15 15 25 25 15 15 60
10 30 10 30 10 30 10 30 12
25 120 25 120 25 60 25 60 35
combined combined combined combined combined combined combined combined combined
P4A P4A P4A P4A P4A P4A P4A P4A P4
1,5 1,5 1,8 1,8 1,8 1,8 2,1 2,1 0,5
3
BSA 3
AT1
60
25
40
combined
P4
0,5
–
BSD
AT1
60
20
50
combined
Special
0,5
0
Main features, speed rating and size range for different bearing design
Radial load Fig
3
Codes: A
= Angular Contact Ball Bearing, Single direction; AT2 = Angular Contact Thrust Ball Bearing, Double direction; C1 = Cylindrical Roller Bearing, Single row; C2 = Cylindrical Roller Bearing, Double row; Hybrid = Bearing with steel rings and silicon nitride (ceramic) rolling elements
14
➤
3
1
15
1 Principles of bearing selection and application Radial loads Purely radial loads can be supported by cylindrical roller bearings having one ring without flanges (N, NN and NNU types figs 3 page 14 and 4 ). All other radial bearings can carry some axial load in addition to radial loads; see Combined load page16. Axial loads Double direction angular contact thrust ball bearings series 2344(00) and BTM are designed to take loads that are purely axial (➔ fig 5 ). For large bearing arrangements, or those subjected to particularly heavy axial loads, special single direction thrust ball bearings or cylindrical roller thrust bearings are recommended. Please consult the SKF application engineering service for more details.
Radial load
Thrust load Fig
16
4
Combined loads Combined loads consist of a radial load and a simultaneously acting axial load. This type of load can be accommodated by bearings having raceways in the inner and outer rings, situated at an angle to the bearing axis. Where high-precision bearings are concerned, the angular contact ball bearings (series 70, 719 and 72) and the single direction angular contact thrust ball bearings (series BSD and BSA) fall into this category. The ability to carry axial loads is determined by the angle of contact; the larger the angle, the greater the axial load, which can be accommodated (➔ figs 6 and 7 ).
Combined loads Fig
5
Combined loads Fig
6
Fig
7
Load carrying capacity and life
1
General
Rating lives
All general information on life, basic load rating, and life equations described in the SKF General Catalogue or the SKF Interactive Engineering Catalogue also applies to high-precision bearings. In general-machinery applications, the size of bearing to be used is initially selected on the basis of its load carrying capacity in relation to the loads to be carried, and the requirements regarding life and reliability. For machine tool spindles, bearing size is nearly always determined by criteria such as stiffness of the system, fixed dimensions for the tool holder, or the spindle bore. The bearings selected according to such criteria give arrangements that are often required to have a very long life. For high-precision bearings, determining the load to which a bearing will be subjected is particularly complex as it involves many influencing factors. SKF has therefore developed special computer programs for the calculation of indeterminate spindle bearing systems. Contact SKF for assistance in determining the bearing loads and in designing an optimum bearing arrangement.
Basic rating life equation For calculation of simple bearing systems, the classic ISO equation for basic rating life can be used: L10 = (C/P)p where L10 = basic rating life, millions of revolutions C = basic dynamic load rating, N P = equivalent dynamic bearing load, N p = exponent of the life equation (3 for ball bearings, 10/3 for roller bearings) Adjusted rating life equation As there are many other factors influencing bearing life besides load, ISO introduced an adjusted life equation Lna = a1 a2 a3 (C/P)p or simply Lna = a1 a2 a3 L10 where Lna = adjusted rating life, millions of revolutions (the index n represents the difference between the requisite reliability and 100 %) a1 = life adjustment factor for reliability a2 = life adjustment factor for material a3 = life adjustment factor for operating conditions
17
1 Principles of bearing selection and application SKF Life Theory – rating life equation. Practical experience and modern research have shown that, under special conditions, SKF bearings attain a much longer life than predicted by standardised life calculation methods, particularly when loads are light. These special conditions apply when the rolling surfaces (raceways and rolling elements) are effectively separated by a lubricant film, and where the risk of the surfaces becoming damaged by contaminants are largely non-existent. In fact, under ideal conditions it is possible to speak of infinite life. The SKF Life Theory introduces the concept of a fatigue load limit Pu analogous to that used when calculating other machinery components. This fatigue load limit represents the load below which fatigue will not occur in the bearing under ideal conditions. Due to the complexity, a detailed description of the theory is beyond the scope of this publication. For further details, please consult SKF application engineering services. Values of the Pu limit for precision bearings are given in the bearing tables. The adjusted life equation according to the SKF Life Theory is: Lnaa = a1 aSKF L10 where: Lnaa = adjusted rating life to SKF Life Theory, millions of revolutions L10 = basic rating life, millions of revolutions a1 = life adjustment factor for reliability aSKF = life adjustment factor based on SKF Life Theory
Rating life equation for hybrid bearings
Load carrying capacity of bearing sets
When using hybrid bearings, the effect of the different rolling element material should also be taken into account. Under the same external load, the stress in the contact area between a hybrid bearing ball and each raceway will be higher than in an all-steel bearing. This is due to the greater hardness and stiffness of the ceramic material compared with steel. As ISO does not provide guidelines for calculating basic load ratings for hybrid bearings, SKF quotes the same load rating values for hybrid bearings as for all-steel bearings. By introducing a factor aHC into the life equations, the higher contact stress is taken into consideration.
The basic load ratings listed in the product tables for angular contact ball bearings and single direction angular contact thrust ball bearings apply to single bearings. The basic dynamic load rating for sets of bearings arranged back-to-back, face-to-face or in tandem, is obtained by multiplying the C value for a single bearing by
L10 (hybrid) = aHC (C/P)p Lna (hybrid) = a1 a23 aHC (C/P)p Lnaa (hybrid) = a1 aSKF aHC (C/P)p Recent results from practical experience and extensive laboratory testing indicate that the factor aHC can be considered equal to 1 both for hybrid ball and roller bearings. In general, experience shows that the service life of hybrid bearings is significantly longer than that of all-steel bearings under the conditions normally encountered in machine tool operations. Hybrid bearings are much less susceptible to wear, and lubrication conditions are generally superior to those in an all-steel bearing.
1,62 for sets comprising two bearings 2,16 for sets comprising three bearings 2,64 for sets comprising four bearings. For the basic static load rating, values for bearing sets can be obtained by multiplying the single bearing value by the number of bearings in the set, viz. by 2, 3, or 4. For single direction angular contact thrust ball bearings, refer to the product section, Table 10 page 247.
Equivalent bearing loads Equivalent dynamic bearing load Angular contact ball bearings are generally subjected to combined loads, i.e. radial and axial loads acting simultaneously. Preload forces are included in the axial load. In all such cases, it is necessary to calculate the equivalent dynamic bearing load that has the same influence on bearing life as the actual load to which the bearing is subjected. The equivalent dynamic bearing load can be obtained from the general equation: P = XFr + YFa where P = equivalent dynamic bearing load, N Fr = actual radial bearing load, N Fa = actual axial bearing load, N X = radial load factor for the bearing Y = axial load factor for the bearing All information necessary for calculating the equivalent dynamic bearing load for single bearings and sets of two bearings is given in the relevant product sections. The information does not apply to sets of three, or more bearings, as it cannot be assumed that the load is evenly distributed over the bearings, and reaction forces caused by spindle deflection cannot be ignored. Special SKF computer programs are used to calculate the equivalent dynamic loads of such bearing arrangements and other parameters, e.g. spindle deflection. Further information will be supplied on request.
For details on the aSKF life adjustment factor, please consult the SKF General Catalogue or the SKF Interactive Engineering Catalogue.
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19
1
1 Principles of bearing selection and application Equivalent static bearing load Static loads comprising radial and axial components must be converted into an equivalent static bearing load. This is defined as that load (radial for radial bearings and axial for thrust bearings) which, if applied, would cause the same permanent deformation in the bearing as the actual load. It is obtained from the general equation P0 = X0Fr + Y0Fa where P0 = equivalent static bearing load, N Fr = actual radial bearing load, N Fa = actual axial bearing load, N X0 = radial load factor for the bearing Y0 = axial load factor for the bearing
All information and data necessary for the calculation of the equivalent static bearing load for single bearings and sets of two bearings is given in the relevant product sections. The information does not apply to sets of three, or more bearings, as it cannot be assumed that the load is evenly distributed over the bearings, and reaction forces caused by spindle deflection cannot be ignored. Further information will be supplied on request.
Rigidity System rigidity Bearing rigidity influences the rigidity of a bearing arrangement and thus the rigidity of the complete spindle/bearing system. It is of particular importance in machine tool applications, as the magnitude of the deflection under load determines the machining accuracy of a machine tool. The rigidity of a bearing depends on its type and size, the most important criteria being: ● type of rolling elements (rollers or balls) ● number and size of rolling elements, and ● contact angle. To enhance the rigidity of the bearing arrangement, or to increase running accuracy, bearings can be preloaded. These are two important reasons why machine tool spindles are almost always fitted with preloaded bearings or bearing sets. Apart from the bearings, other components might influence the rigidity of a system i.e. bending of the spindle itself, position and number of support bearings, and tool overhang. Thus, it is necessary to consider how different bearing arrangements behave and how they contribute to the system’s overall rigidity. The rigidity indexes given in Table 1 page 22 are guideline values and must not be taken as tools for precise calculations of system rigidity.
20
1
General guidelines for designing a rigid spindle are: ● select the largest possible shaft diameter compatible with other restrictions ● minimise the distance between the front support position and the spindle nose ● bearing spacing (between rear and front supports) should be fairly short. As a guideline, a ratio I/d = 3 − 3,5 provides the best compromise, where I = distance between the rearmost bearing row and the first front side bearing row, and d = bore diameter of the front bearing. Please consult the SKF application engineering service for advanced system analysis. Table 1 shows the radial and axial stiffness of a 100 mm shaft diameter spindle where different bearing arrangements are compared.
21
1 Principles of bearing selection and application
Influence of a loose fit In general, a machine component is supported in a locating and a non-locating bearing. Non-locating bearings can be displaced axially and so prevent the bearings from being subjected to extra stresses, e.g. as a result of changes in shaft length caused by thermal expansion.
If non-separable bearings, e.g. angular contact ball bearings, are used as nonlocating bearings, one of the bearing rings must have a loose fit. Usually the nonrotating outer ring is given a loose fit in the housing, although this has a negative influence on the total stiffness of the bearing arrangement.
Speed
1
Rotational speed
high-speed operation. Generally speaking, ball bearings are preferred for high speed. The following graphs gives guidelines on the attainable speeds from different bearing designs and executions with grease and oil lubrication (➔ Diagrams 1 and 2 page 24).
The permissible operating temperature governs largely the speed at which rolling bearings can operate. Bearing types with low friction and thus low heat generation in the bearing itself are the most suitable for Table Bearing arrangement Rear side
Tool side
Rigidity index Radial
Axial
NN 30 KTN NN 30 KTN NN 30 KTN N 10 KTN N 10 KTN N 10 KTNHA
2344(00) + NN 30 KTN BTM – B + NN 30 KTN BTM – A + NN 30 KTN BTM – A + NN 30 KTN 70 CD/QBCB 719 CE QBCB
100 100 100 98 76 74
100 67 44 44 45 34
NN 30 KTN 719 CD/DBA NN 30 KTN 70 CD/DBA 70 CD/DBA N 10 KTNHA
719 ACD/TBTB 719 ACD/TBTB 70 CD/TBTB 70 CD/TBTB 70 ACD/TBTB 70 CE QBCB
67 67 67 67 63 63
75 75 36 36 74 30
70 CE/HCDT 70 CD/DBA 719 CE/HCDBA 70 CE/DT N 10 KTNHA 719 CE/DBA
70 CE/HCDT 70 ACD/DBB 719 ACE/HCTBTA 70 CD/DT 70 CE/DBB 719 ACE/TBTA
55 54 49 49 47 40
33 48 48 30 16 42
70 CD/HCDBA N 10 KTNHA/HC5 70 CE/DBA N 10 KTNHA 719 CE/DBA 70 CE/DBA N 10 KTNHA
70 ACE/HCDBA 70 ACE/HCDBA 70 ACE/TBTA 719 ACE/DBA 719 ACE/DBA 70 ACE/DBA 70 ACE/DBA
39 38 37 36 36 34 34
28 28 41 26 26 25 25
1
Relative stiffness of spindles equipped with different bearing arrangements
Bearing design
22
Speed guidelines for different bearing designs Oil spot lubrication
70-719 CE/HC 70-719 CE 70-719 ACE/HC N 10 KTNHA/HC5 70-719 ACE 70-72-719 CD/HC and CX/HC 70-72-719 CD and CX N 10 KTNHA 70-72-719 ACD/HC and ACX/HC NN 30 KTNHA/HC5 70-72-719 ACD and ACX BTM – A/HC NN 30 KTNHA N 10 K N 10 K/HC5 NN 30 K/HC5 NN 30 K BTM – A BTM – B/HC BTM – B 2344(00) 0
The table above specifies the relative stiffness, calculated on a real spindle design having 100 mm shaft diameter at the tool side and 90 mm shaft diameter at the rear side. It must be taken into account that the shaft length (i.e. the distance from the first and last bearing centres) has an important influence on actual rigidity, while axial stiffness may be influenced by the actual preload in operation
1
Diagram
0,5
Catalogue speed Field experience Special designs
1
1,5
2
2,5
3
3,5
4
Speed factor, n dm (× 106)
23
1 Principles of bearing selection and application Wg is the result of several factors such as the temperature of the environment, the heat generated by motors, electrical losses, friction in the bearings, friction of the lubricant, etc. The heat generated by the bearings themselves has many causes, i.e. the bearings internal design, the material of the rings and rolling elements, the type of lubrication, the loads acting on the bearings (including preloading) etc. When Wn is insufficient to stabilise the system temperature to the desired value, it is necessary to modify the design of the system to reduce Wg. If this is not possible, a cooling system must be introduced to re-establish the thermal equilibrium. This can be done by air-cooling the entire system, by using chilled air in the oil spot lubrication system, or by using the oil jet method, making the oil the vehicle for heat, transfer from the system to another area.
However, the primary parameter that sets the actual limit for the operating speed in bearing systems is the maximum permissible temperature for safeguarding the lubricant life and the complete system’s thermal stability. The operating temperature of the system depends on a number of factors, and bearings are only one consideration. To obtain thermal stability it is always necessary that Wg = Wd = Wn + Wc where Wg is the generated heat in the system and Wd is the heat dissipated by the system, which comes partly from natural dissipation, Wn, and partly is obtained by forced cooling, Wc. In many cases where no cooling acts on the system, Wc = 0.
Diagram
2
Bearing design 70-719 CE/HC 70-719 CE 70-719 ACE/HC N 10 KTNHA/HC5 70-719 ACE 70-72-719 CD/HC and CX/HC 70-72-719 CD and CX N 10 KTNHA 70-72-719 ACD/HC and ACX/HC NN 30 KTNHA/HC5 70-72-719 ACD and ACX BTM – A/HC NN 30 KTNHA N 10 K N 10 K/HC5 NN 30 K/HC5 NN 30 K BTM – A BTM – B/HC BTM – B 2344(00) 0 Catalogue speed Field experience
24
0,5
1
1,5
Speed guidelines for different bearing designs Grease lubrication
Speed ratings The speed ratings quoted in the product tables are guideline values and are valid, provided that the bearings are lightly loaded, that they are lightly preloaded and that the transport of heat away from the bearing position is good. The values under oil spot lubrication are maximum values and should be reduced for other methods of oil lubrication, other than those involving minimum oil quantities are applied, or where additional cooling is not
provided. A 0,3 – 0,4 reduction factor should be considered with oil bath, while a 0,95 factor should be considered for oil mist lubrication. Conversely, oil jet might allow higher speeds than those given for oil spot, but it depends very much on oil type, oil supply rate, oil inlet temperature, oil drainage efficiency, etc. Please consult the SKF application engineering service for details. The values under grease lubrication are maximum values that can be attained using a good quality grease of soft consistency.
Table arrangement1)
Bearing Rear side
Work side
Speed index Oil Grease
NN 30 KTN NN 30 KTN NN 30 KTN N 10 KTNHA N 10 KTNHA N 10 KTNHA NN 30 KTN 719 CD/DBA NN 30 KTN 70 CD/DBA 70 CD/DBA N 10 KTNHA 70 CE/HCDT 70 CD/DBA 719 CE/HCDBA 70 CE/DT N 10 KTNHA 719 CE/DBA 70 CD/HCDBA N 10 KTNHA/HC5 70 CE/DBA N 10 KTNHA 719 CE/DBA 70 CE/DBA N 10 KTNHA
2344 + NN 30 KTN BTM – B + NN 30 KTN BTM – A + NN 30 KTN BTM – A + NN 30 KTN 70 CD QBCB 719 CE QBCB 719 ACD/TBTB 719 ACD/TBTB 70 CD/TBTB 70 CD/TBTB 70 ACD/TBTB 70 CE QBCB 70 CE/HCDT 70 ACD/DBB 719 ACE/HCTBTA 70 CD/DT 70 CE/DBB 719 ACE/TBTA 70 ACE/HCDBA 70 ACE/HCDBA 70 ACE/TBTA 719 ACE/DBA 719 ACE/DBA 70 ACE/DBA 70 ACE/DBA
84 100 100 100 102 107 100 118 100 124 110 88 312 140 225 262 176 190 240 240 173 213 220 200 200
1
Relative speed capability of bearing systems for machine tool spindles equipped with different bearing arrangements
70 84 89 89 60 64 70 70 73 73 66 56 204 84 144 180 120 121 150 150 112 140 140 130 130
2
Speed factor, n dm (× 106)
1)
Reference size: work size bearings 80 mm bore diameter; rear side bearings 70 mm bore diameter
25
1
1 Principles of bearing selection and application
Speed capability of bearing systems When designing a spindle, a bearing system will be used. The system may be composed of various bearing arrangements, normally a set of bearings at the work side, and another set at the drive side (rear end). The spindle speed must be evaluated on
the most critical bearing set, normally the one at the tool side, which is bigger in bore diameter, forcing it towards high values of the speed factor n dm. Table 1 page 25 provides a comparison of possible choices in this respect. A comparison of temperature rise versus speed for grease-lubricated spindles based on actual field results is shown in Diagram 3 .
Temperature rise from existing applications Grease lubrication Diagram
Temperature rise above ambient, °C 35
3
Bearing data – general Dimension High-precision bearings, similarly to rolling bearings in general, are manufactured with very few exceptions, according to Dimension Plans for the boundary dimensions issued by the International Organisation for Standardisation (ISO). More precisely, boundary dimensions follow the ISO Dimension Plan for radial bearings ISO15: 1998, where a progressive series of standardised outside diameters (Diameter Series 7, 8, 9, 0, 1, 2 etc., in order of increasing outside diameter), are set for every standard bore diameter. Within each Diameter Series different Width Series are also established (Width Series 8, 0, 1, 2, 3 etc., in order of increasing width).
1
The Width Series for radial bearings correspond to the Height Series for thrust bearings (Height Series 7, 9, 1 and 2 in order of increasing height). By combining a Diameter Series with a Width or Height Series, Dimension Series, designated by two figures, are arrived at. The first figure identifies the Width Series and the second the Diameter Series. The bearings in this catalogue comply with the ISO Dimension Plans, with the exception of double direction angular contact thrust ball bearings and single direction angular contact thrust ball bearings belonging to metric series, whose boundary dimensions are not standardised, but recognised by the market and used by the manufacturers as such.
30 25 20 15 10 5 0 0,25
0,3
0,41
0,49
0,57
0,66
0,74
0,82
0,99
1,15
1,2
1,35
1,45
1,57
1,62
Speed factor, n dm (× 106)
26
70 CD/DBA
70 CE/HCDBA
719 CD/QBCA
BTM 100 A/DB
70 CD/TBTA
70 CE/HC Spring
NN 30
2344..
27
1 Principles of bearing selection and application
Tolerances Tolerance classes for bearings are internationally standardised. Depending on the bearing type, SKF High-precision bearings are manufactured to the following tolerances (➔ Table 1 ). Actual tolerance values are equal to or better than those specified by the following international standards: ● ISO 199:1997 Rolling bearings-Thrust bearingsTolerances ● ISO 492:2002 Rolling bearings-Radial bearingsTolerances ● ANSI/ABMA Std. 20-1996 Radial bearings of ball, cylindrical roller and spherical roller types, Metric design ● DIN 620-2:1999 Rolling bearings-Tolerances for radial bearings ● DIN 620-3:1982 Rolling bearings-Tolerances for thrust bearings
∆ds
Tolerance symbols Following are explanations for the symbols used in the tolerance tables:
Vdp
Symbol Definition d Nominal bore diameter dmp Mean bore diameter, arithmetical mean of the largest and smallest single bore diameters in one plane ds Single diameter of bore ∆dmp Deviation of the mean bore diameter from the nominal ∆d2mp Deviation of the mean bore diameter at large end of tapered bore (for cylindrical roller bearings), arithmetical mean of the largest and smallest single bore diameters at distance “a” ∆d3mp Deviation of the mean bore diameter at small end of tapered bore (for cylindrical roller bearings), arithmetical mean of the largest and smallest single bore diameters at distance “a”
Vdmp
D Dmp
Ds ∆Dmp ∆Ds VDp
VDmp
Bs, Cs Cs B1s, C1s
High-precision bearing tolerance classes Table Radial angular contact ball bearings
P4A and PA9A
Radial cylindrical roller bearings
SP and UP
Single direction angular contact thrust ball bearings (ball screw support bearings)
P4
Double direction angular contact thrust ball bearings series 2344(00)
SP and UP
Double direction angular contact thrust ball bearings series BTM – A and BTM – B…
P4C
28
1
∆Bs, ∆Cs ∆Cs
Deviation of a single bore diameter from the nominal Bore diameter variation; difference between the largest and smallest single bore diameters in one plane Mean bore diameter variation; difference between the largest and smallest mean bore diameters of one ring Nominal outside diameter Mean outside diameter, arithmetical mean of the largest and smallest single outside diameters in one plane Single diameter of outside cylindrical surface Deviation of the mean outside diameter from the nominal Deviation of single outside diameter from the nominal Outside diameter variation; difference between the largest and smallest single outside diameters in one plane Mean outside diameter variation; difference between the largest and smallest mean outside diameters of one ring Single width of inner ring and outer ring, respectively Single height (width) of housing washer (For bearing series 2344(00)) Single width of inner ring and outer ring, respectively, of bearings made for paired mounting Deviation of single inner ring width or single outer ring width from the nominal Deviation of single housing washer height (width) from the nominal
∆B1s, ∆C1s
VBs, VCs
Kia, Kea Sd SD
Sia, Sea
Si, Se
Ts ∆Ts
Deviation of single inner ring width or single outer ring width from the nominal of a bearing specially manufactured for paired mounting Ring width variation; difference between the largest and smallest single width of inner ring and outer ring, respectively, Radial runout of assembled bearing inner ring and assembled bearing outer ring, respectively Side face runout with reference to bore (of inner ring) Outside inclination variation; variation in inclination of outside cylindrical surface to outer sideface Side face runout with reference to raceway of assembled bearing inner ring and assembled bearing outer ring respectively Thickness variation, measured from middle of raceway to back (seating face) of shaft washer and housing washer, respectively Single height of thrust bearing Deviation of single height of thrust bearing from the nominal
Limits of chamfer dimensions To prevent the improper dimensioning of associated components for rolling bearings and to facilitate the calculation of retaining ring location arrangements, minimum values for the chamfer dimensions in the radial direction (r1, r3) and the axial direction (r2, r4) are given in the product tables These values conform to ISO 582:1995 for metric bearings with series designations. Maximum values associated with these minimum chamfer dimensions are found in the standards
29
1
1 Principles of bearing selection and application
Bearing internal clearance or preload All bearings, are designed in a way to get, in unfitted conditions, a certain amount of internal clearance that can be radial or axial, depending on the direction one of the rings can be moved, with respect to the other. This clearance value, fixed at the design stage, nevertheless, is reduced after mounting; because of the fitting conditions (interference) the bearing is subjected to and/or because of the thermal expansion or compression of the rings. Thus, operational clearance is the key parameter for a correct bearing operation. To ensure maximum running accuracy and rigidity of the system, bearings used in machine tool spindles should have a minimum radial internal clearance or a preload after mounting. This is most valid for angular contact ball bearing sets, which are prepared at a certain step of the manufacturing process, in a way, that after fitting them on the shaft, the required preload is obtained.
30
Similarly, double direction angular contact thrust ball bearings are set up, in a way, to get a fixed static preload after mounting on the shaft. Conversely, cylindrical roller bearings are supplied with radial clearance according to different possible classes. Depending on the speed operations, and on the thermal expansion or compression of the rings expected, the operational clearance can be set up at the required value, by driving the inner ring of the bearing on its tapered seat. For relatively low speed a certain amount of radial preload can be applied. The clearance values for cylindrical roller bearings and the preload values for matched single row angular contact ball bearings, and single and double row angular contact thrust ball bearings will be found in the relevant tables in the product sections.
Materials for high-precision bearings The performance and reliability required from high-precision bearings implies the use of adequate materials for rings, rolling elements and cages. Steel for bearing rings and rolling elements The standard SKF steel for high-precision bearings is, according to the usual classification, a “high carbon” content one (more than 0,5 %). Additional alloying elements such as Chromium, Manganese and Molybdenum are included in the steel composition to obtain the necessary properties in the finished components. By means of the heat treatment and the resulting changes in the microstructure of the steels, the mechanical properties of the components can be addressed to specific requirements. Rings and rolling elements of SKF highprecision bearings are made of typical martensitic through-hardened steel that provide sufficient resistance to sub-surface rolling contact fatigue, sufficient static capacity and structural strength combined with adequate dimensional stability. SKF high-precision bearings can generally be used up to 120°C. When operating temperatures exceed this value a special heat treatment (stabilisation) has to be
adopted, so that it is possible to get the required dimensional stability, avoiding changes in dimension that could result in premature bearing failure. In order to significantly improve the resistance to corrosion, the use of nitrogen as an alloying element has been introduced in a newly developed bearing steel. Nitrogen leads to precipitation of chromium nitrides rather than chromium carbides, enabling a much higher content of chromium to be dissolved in the steel matrix, resulting in a better resistance to oxidation, and in a longer service life of the bearings. It is advisable to contact SKF regarding the selection and application of nitrogen steel bearings. Ceramic materials for rolling elements Within the various ceramic materials, the hot isostatic pressed silicon nitride identified with the chemical formula Si3N4 is commonly used for rolling elements, in both balls and rollers. Silicon nitride is hard and its main properties are high modulus of elasticity, low density and thermal expansion. The modulus of elasticity of silicon nitride is some 50 % higher than for steel. This means that a ceramic rolling element under load does not distort to the same extent, and in turn, the contact between rolling elements and rings is smaller. So there is less friction.
31
1
1 Principles of bearing selection and application The density of silicon nitride rolling elements is 60 % lower than that of steel of the same size. This leads to considerably reduced centrifugal loads and consequently reduced stresses. Furthermore, for angular contact ball bearings, the lower density has a beneficial effect on contact angle variation at high speeds, leading to reduced ball sliding and consequently to reduced friction. The thermal expansion of silicon nitride is less than 30 % that of steel and this, in cases, where the difference in temperature between inner ring (usually warmer than outer ring) and outer ring is not negligible, reduces the clearance reduction and/or preload increase, hence reducing the risk of drastic failure. A comparison of the physical properties of silicon nitride Si3N4 and bearing steel is shown in Table 2 .
Bearings assembled with steel rings and ceramic rolling elements are commonly called hybrids. Compared to standard all-steel bearings they can run at higher speeds with a certain temperature increase, or at the same speeds with a lower temperature increase. They have also a greater rigidity, both under dynamic and static conditions. They are less sensitive to temperature differences between the rings, and the preload increase is smaller than for normal bearings. The low coefficient of friction of silicon nitride enhances their wear resistance and enables them to run cooler under poor lubrication conditions. Moreover, silicon nitride is hard, tough and strong and these properties combined with a better surface finish give better resistance to damage from particles and impurities that may enter the bearing.
Properties of silicon nitride and bearing steel Table Property
Unit
Silicon nitride Si3N4
Bearing steel, hardened
Density, ρ
g/cm3
3,2
7,9
Coefficient of thermal expansion 20 – 1 000 °C 20 – 300 °C
×10−6/K
Modulus of elasticity, E
GPa
310
210
Poisson’s ratio
-
0,26
0,3
1 600
700
800 800
2 400 0
7
25
3,2 11,5
Hardness HV10
kg/mm2
Tensile strength 20 °C 1 000 °C
MPa
Fracture toughness, KIC
MPa.m1/2
Thermal conductivity
W/mK
30 – 40
40 – 50
Specific electrical resistivity
Ωm
1012
0,4 × 10−6
32
2
Material for cages The main purpose of the cage is to keep the rolling elements at an appropriate distance from each other and to prevent immediate contact between two neighbouring rolling elements, in order to keep friction and consequently heat generation at a minimum. Materials and the shape of cages for high-precision bearings have been developed parallel to the development of the bearings and to the requirements they have to satisfy. High-precision bearing cages are mechanically stressed by frictional strain and inertia forces. They might also be subjected to chemical action of certain lubricants. Thus, the design and choice of material are of paramount importance for the performance of the cage, as well as for the operational reliability of the bearing as a whole. For each of the bearings shown in the product tables one particular cage design is established as the standard cage for that bearing. The standard cage is always well proven in service and is the design considered most suitable for the majority of applications. In the introductory text to each table section information is provided regarding the standard cages bearings are fitted with and also the possible alternatives. Machined outer ring land-riding fabric-reinforced phenolic resin cages are used for most of the angular contact ball bearings. This material is lightweight resulting in minimal centrifugal forces and having the capability of retaining part of the lubricant,
ensuring optimum lubrication. Fabricreinforced phenolic resin cages should not be used at temperatures exceeding 120°C. Moulded glass fibre reinforced polyamide cages are normally fitted in cylindrical roller bearings and single and double row angular contact thrust ball bearings. This material is characterised by a favourable combination of strength and elasticity. The good sliding properties of the polyamide on lubricated steel surfaces and the smoothness of the cage surface in contact with the rolling elements results in little friction from the cage, with minimum heat generation and wear in the bearing. They can be used for operating temperatures not exceeding 120°C. When higher speeds or better performances need to be reached, as in the case of angular contact ball bearings or single row cylindrical roller bearings, glass fibre reinforced PEEK (poly-ether-etherketone) cages are chosen. The injection moulding process used to produce these cages allows functionally suitable designs to be realised. Moreover, PEEK offers a better stability and rigidity than polyamide. For lower speeds and higher loads, as in the case of large size double row cylindrical roller bearings or double direction angular contact thrust ball bearings, machined brass cages generally centred on the rolling elements are selected. For special applications, where high temperatures or poor lubrication are involved, silver-plated steel or brass cages can represent the optimal solution.
33
1
1 Principles of bearing selection and application
Application of bearings Bearing arrangements General The classic application field for highprecision bearings is machine tools spindles, which may have different requirements depending on the working operations they are designed for. Generally, lathe spindles are used to cut metals at rather low speeds and in combination with relatively large cutting loads. Such types of spindles usually have the driving torque transmitted through a pulley or toothed gears. This means that loads at the rear side of the shaft are also rather heavy. For such applications, the requirements in terms of speed are not so tough; the more important parameters are rigidity and load carrying capacity. It is quite common to have, at the front side of the spindle, a double row cylindrical roller bearing in combination with a double row angular contact thrust ball bearing, while having a double row cylindrical roller bearing at the rear end of the shaft. This type of arrangement ensures a long calculated life
34
and an excellent rigidity, so that a good quality of the workpiece is obtained. Also, from a kinematic point of view, the bearings run in a stable way, as there are two types of bearing (radial and axial) that carry independently, the loads applied on the shaft (in fact, to avoid that angular contact thrust ball bearings carry radial loads, the outer ring outside diameter has a special tolerance so that it is never in contact with the housing). When designing these types of spindles (this applies in general when rather heavy loads are involved) a good rule of thumb concerning the position of the bearings along the shaft, is to have the distance between the centre of the front and rear support in the range of 3 – 3,5 times the bearing inner diameter. When higher speeds are requested (i.e. high-speed machining centre or internal grinding) different bearing solutions need to be found. Obviously, in such cases something has to be paid in terms of rigidity, as well as carrying capacity. High-speed applications usually have direct-driven spindles driven by direct coupling and/or
electrical motors (i.e. the so called motorised spindles). There are no loads due to transmission of power and consequently single row angular contact ball bearings paired in sets or single (for extremely high speed) and single row cylindrical roller bearings are frequently adopted, if enhanced performances are required, equipped with silicon nitride rolling elements. The front side bearing set is axially located, whilst mounting a cylindrical roller bearing at the rear side permits axial displacement, due to spindle elongation. When very high speeds are involved (n dm factor over 2 million) it is quite common to see angular contact ball bearings on both sides, preloaded by springs. This is done to control the heat generation. If sets of angular contact ball bearings arranged in a constant position are chosen, preload would increase with the speed, and at high speed produce an amount of heat which is not sustainable. Conversely, spring preload remains constant with the speed, thus ensuring a more correct kinematic behaviour and a limited amount of heat generation. An even better solution is represented by the possibility to preload the bearings (angular contact) by a hydraulic system. In such a case, the amount of preload can be adjusted according to the speed of the spindle, thus reaching the best possible combination among rigidity, heat generation and theoretical life of the bearings.
Radial location of bearings General In order to work properly, bearings must have their rings or washers fully supported around their complete circumference and across the whole width of the raceway. The support must be firm and even, and can be provided by a cylindrical or tapered seating or, for thrust bearing washers, by a flat (plane) support surface. This means that the seatings must be made with adequate accuracy and that their surface should be uninterrupted by grooves, holes or other features. This is particularly important with high-precision bearings since they have relatively thin-walled rings, which adapt themselves to the form of the shaft or housing bore. In addition, the bearing rings must be reliably secured to prevent them from turning on or in their seatings under load. A satisfactory radial location and an adequate support can generally be obtained when the rings are mounted with an appropriate degree of interference. Inadequately or incorrectly secured bearing rings generally cause damage to the bearings and associated components. However, when easy mounting and dismounting are desirable, or when axial displacement is required with a non-locating bearing, an interference fit cannot be used. In certain cases where a loose fit is employed it is necessary to take special precautions to limit the inevitable wear, for example, surface hardening of the seating and abutments.
35
1
1 Principles of bearing selection and application
Application examples
1
Spindle arrangements for heavy machining, CNC lathes and conventional milling machines (➔ figs 1 , 2 and 3 ).
Bearing arrangement work side: 70 ACD/P4ATBT; drive side NN 30 K
Bearing arrangement work side: NN 30 K + 2344(00); drive side NN 30 K
2
Fig
3
Bearing arrangement work side: N 10 KTN + BTM-A/HC; rear side N 10 KTN Fig
36
Fig
1
37
1 Principles of bearing selection and application Spindle arrangements for great rigidity and high speed machining centres, high speed turning centres and high speed milling (➔ figs 4 , 5 , 6 and 7 ).
1 Bearing arrangement work side: 70 CE/HCP4ADB; rear side N 10 KTN
Bearing arrangement work side: 70 CE/HCP4AQBC; rear side 70 CE/HCP4A Fig
4
6
Fig
7
Bearing arrangement work side: 70 CD/P4ADB; rear side N 10 KTN
Bearing arrangement work side: 70 CD/P4AQBC; rear side 70 CD/P4A Fig
38
Fig
5
39
1 Principles of bearing selection and application Spindle arrangements for maximum speed, internal grinding machines (➔ figs 8 and 9 ).
Bearing arrangement for live centres (➔ fig 10 ).
Bearing arrangement work side: 70 CE/HCP4A; rear side 70 CE/HCP4A
Bearing arrangement work side: NN 30 K ; rear side 72 ACD/P4AQBT Fig
8
Fig
9
1
Fig 10
Bearing arrangement work side: 70 CD/HCP4ADT; rear side 70 CD/HCP4ADT
40
41
1 Principles of bearing selection and application Table
Recommended fits Appropriate shaft and housing tolerances for high-precision bearings are shown in Tables 1 and 2 . However, in the specific case of spindle applications with normal load and speed conditions, the interference/ clearance fit between bearings, shaft and housing shown in Tables 3 and 4 page 44 are recommended. The table of housing tolerance recommendations also gives information as to whether the outer ring can be axially displaced in the housing bore. For extreme conditions, such as very high speed or exceptional loading, please consult SKF application engineering services.
Bearing type
Operating conditions
Angular contact ball bearings
Non-locating bearings, displacement of outer ring desired Locating bearings, displacement of outer ring not required Rotating outer ring load
H51)
H41)
JS5 M5
JS4 M4
Normal and light loads Heavy loads, rotating outer ring loads
K5 M5
K4 M4
– –
H5 K5
– K4
Cylindrical roller bearings
Angular contact thrust ball bearings Single direction Double direction2)
1) 2)
2
1
Tolerance Bearings of tolerance class P4A, SP, P4C PA9A, UP
The upper half of the recommended tolerance range should be used, especially when important drive loads (belts, gears) are acting at the spindle drive side The 2344(00) and BTM series bearings are mounted with radial clearance in the same housing bore seating as the appropriate cylindrical roller bearing. Fits tighter than those recommended should never be used even if they are required for cylindrical roller bearings
Fits for steel shafts (solid and hollow) Table Bearing type
Angular contact ball bearings with rotating outer ring load with rotating inner ring load Cylindrical roller bearings with cylindrical bore
Angular contact thrust ball bearings Single direction Double direction
42
Shaft diameter
1
Fits for cast iron and steel housings
Tolerance Bearings of tolerance class P4A, SP, P4C PA9A, UP
over
incl.
mm
mm
– –
240 240
h4 js4
h3 js3
– 40 140 200
40 140 200 240
js4 k4 m5 n5
– – – –
– –
130 200
h4 h4
– h3
Preferred fits on the shafts Table Bearing type
Angular contact ball bearings
Bearing bore over incl.
Interference
mm
mm
µm
– 50 80 120 150
50 80 120 150 200
0–2 1–3 1–4 2–5 2–6
3
43
1 Principles of bearing selection and application Table Bearing type
Outside diameter over
incl.
Recommended clearance for bearings axially located free (non-located)
mm
mm
µm
Angular contact ball bearings
– 50 120 150
50 120 150 250
0–2 0–3 0–4 0–5
Bearing type
Outside diameter over
incl.
mm
mm
5–8 6 – 10 8 – 12 10 – 15
4
Specific recommendations for single direction angular contact thrust ball bearing seatings are given in the relevant bearing section.
Tolerances for shaft and housing Appropriate shaft and housing tolerances for high-precision bearings will be found in the Table 5 page 46 : ISO shaft limits and Table 6 page 47 : ISO housing limits. The positioning of tolerance zones given in the tables, in relation to the nominal bore and outside diameter of the bearings is shown in Diagram 1 .
Recommended interference
µm
ISO shaft and housing limits, position of the tolerance zones Cylindrical roller bearings
–
460
0–2 Diagram
1
+
Preferred fits in the housings
0
– h4
44
h3
js3
js4
js5
js6
k4
k5
m5
n5
H5
H4
JS4 JS5
K4
K5
M4
M5
45
1
1 Principles of bearing selection and application Table Shaft diameter Nominal over incl.
Tolerances h4 Deviations high low
mm
µm
6 10 18 30 50 80 120 180 250
10 18 30 50 80 120 180 250 315
0 0 0 0 0 0 0 0 0
–4 –5 –6 –7 –8 –10 –12 –14 –16
Shaft diameter Nominal over incl.
Tolerances js6 Deviations high low
mm
µm
6 10 18 30 50 80 120 180 250
10 18 30 50 80 120 180 250 315
ISO shaft limits
46
+4,5 +5,5 +6,5 +8 +9,5 +11 +12,5 +14,5 +16
–4,5 –5,5 –6,5 –8 –9,5 –11 –12,5 –14,5 –16
h3 high
0 0 0 0 0 0 0 0 0
js3 low
–2,5 –3 –4 –4 –5 –6 –8 –10 –12
k4 high
+5 +6 +8 +9 +10 +13 +15 +18 +20
high
+1,25 +1,5 +2 +2 +2,5 +3 +4 +5 +6
js4 low
–1,25 –1,5 –2 –2 –2,5 –3 –4 –5 –6
k5 low
+1 +1 +2 +2 +2 +3 +3 +4 +4
high
+7 +9 +11 +13 +15 +18 +21 +24 +27
high
+2 +2,5 +3 +3,5 +4 +5 +6 +7 +8
js5 low
–2 –2,5 –3 –3,5 –4 –5 –6 –7 –8
m5 low
+1 +1 +2 +2 +2 +3 +3 +4 +4
high
+12 +15 +17 +20 +24 +28 +33 +37 +43
5
high
+3 +4 +4,5 +5,5 +6,5 +7,5 +9 +10 +11,5
low
+6 +7 +8 +9 +11 +13 +15 +17 +20
high
+16 +20 +24 +28 +33 +38 +45 +51 +57
Housing bore diameter Nominal over incl.
Tolerances H5 Deviations high low
mm
µm +9 +11 +13 +15 +18 +20 +23 +25 +27
–3 –4 –4,5 –5,5 –6,5 –7,5 –9 –10 –11,5
18 30 50 80 120 180 250 315 400
low
Housing bore diameter Nominal over incl.
Tolerances K4 Deviations high low
mm
µm
n5 low
Table
+10 +12 +15 +17 +20 +23 +27 +31 +34
18 30 50 80 120 180 250 315 400
30 50 80 120 180 250 315 400 500
30 50 80 120 180 250 315 400 500
0 +1 +1 +1 +1 0 0 +1 0
0 0 0 0 0 0 0 0 0
–6 –6 –7 –9 –11 –14 –16 –17 –20
6
1 H4
JS4
JS5
high
low
high
low
high
low
+6 +7 +8 +10 +12 +14 +16 +18 +20
0 0 0 0 0 0 0 0 0
+3 +3,5 +4 +5 +6 +7 +8 +9 +10
–3 –3,5 –4 –5 –6 –7 –8 –9 –10
+4,5 +5,5 +6,5 +7,5 +9 +10 +11,5 +12,5 +13,5
–4,5 –5,5 –6,5 –7,5 –9 –10 –11,5 –12,5 –13,5
K5
M4
M5
high
low
high
low
high
low
+1 +2 +3 +2 +3 +2 +3 +3 +2
–8 –9 –10 –13 –15 –18 –20 –22 –25
–6 –6 –8 –9 –11 –13 –16 –16 –18
–12 –13 –16 –19 –23 –27 –32 –34 –38
–5 –5 –6 –8 –9 –11 –13 –14 –16
–14 –16 –19 –23 –27 –31 –36 –39 –43
ISO housing limits
47
1 Principles of bearing selection and application Accuracy of associated components Maximum running accuracy, high speeds and low operating temperatures can only be achieved, even with precision bearings, if the mating parts and other associated components are made with equal precision. Deviations from geometric form must therefore be kept as small as possible where the mating parts are concerned. The rings of the bearings shown in this catalogue are relatively thin-walled, so they will adapt themselves to the form of the shaft or housing bore. Any errors of form or other inaccuracies of the shaft and housing bore seating will thus be transmitted to the raceways of the bearing rings. Angular
Fig 11
misalignment of one bearing ring in relation to the other can cause high operating temperatures; the axial support surfaces for the faces of the bearing rings must therefore, be precisely machined. This is particularly important where high-speed operation is intended. Consequently, an important prerequisite to achieving highly accurate bearing arrangements is that the recommendations, concerning accuracy of form and position, as well as surface finish, are adhered to when machining the mating parts (➔ figs 11 and 12 ). Limits for tolerance grades and roughness classes can be found in Tables 7 and 8 page 50.
A
1
B
AB
t3
Accuracy of form for housings 1)
DB
DA
t
ø t 4 /300 1)
t1
B
ø t 4 /300
A
The housing form tolerances, symbols and reference surfaces are in accordance with ISO 1101
Fig 12
Accuracy of form for shafts 1)
t A
t
B
t1
t2
B
dB
dA
t3 ø t 4 /300 1)
48
B
AB ø t 4 /300
A
The shaft tolerances, symbols and reference surfaces are in accordance with ISO 1101
49
1 Principles of bearing selection and application Table Tolerance parameter
Circularity Cylindricity Angularity Runout Coaxiality
t t1 t2 t3 t4
Shaft Tolerance class P4A, SP, P4C
PA9A, UP
IT2/2 IT2/2 IT3/2 IT1 IT4
IT1/2 IT1/2 IT2/2 IT0 IT3
N4 N5 N6
N3 N4 N5
Housings Tolerance class P4A, SP, P4C
PA9A, UP
IT2/2 IT2/2
IT1/2 IT1/2
IT1 IT4
IT0 IT3
N5 N6 N7
N4 N5 N6
Tolerance grades appropriate to spindle bearings
7
General An interference fit alone, is inadequate for the axial location of a bearing ring. As a rule, therefore, some suitable means of axially securing the ring is needed. Both rings of locating bearings should be axially secured at both sides. For non-locating bearings, on the other hand, where they are of a non-separable design, it is sufficient if the ring having the tighter fit – usually the inner ring – is axially secured; the other ring must be free to move axially with respect to its seating. In machine tool applications, usually, the work side bearings ensure the shaft location to support the axial load transmission from the shaft to the housing. Generally, then, work side bearings are axially located, while rear side supports are axially free.
Roughness1) d, D over incl. – 80 250
1)
80 250
Limits for tolerance grades, surface roughness class values 1)
For surface roughness Ra see Table 8 ; roughness classes N to ISO 1302
Table Diameter
Tolerance grades
Nominal over incl.
IT0
mm
µm
IT1
Surface roughness class IT2
IT3
IT4
IT5
6 10 18 30 50 80
10 18 30 50 80 120
0,6 0,8 1 1 1,2 1,5
1 1,2 1,5 1,5 2 2,5
1,5 2 2,5 2,5 3 4
2,5 3 4 4 5 6
4 5 6 7 8 10
6 8 9 11 13 15
120 180 250 315 400
180 250 315 400 500
2 3 4 5 6
3,5 4,5 6 7 8
5 7 8 9 10
8 10 12 13 15
12 14 16 18 20
18 20 23 25 27
1)
50
Axial location of bearings
Roughness
Ra –
µm
N3 N4 N5 N6 N7
0,1 0,2 0,4 0,8 1,6
8
Stepped sleeves Stepped sleeves may be used to axially lock bearings or other precision components on a shaft. Compared to threaded locking nuts, stepped sleeves ensure a superior accuracy, provided they are manufactured to a high degree of accuracy. Conversely, stepped sleeves are expensive to manufacture, have to be designed properly, and require proper mounting procedure. Stepped sleeves are generally used in very high-speed spindles, where the accuracy granted by conventional locking devices may not be sufficient. Stepped sleeves are not standardised and can be designed in many different ways to suit the spindle design.
Methods of location Bearing rings having an interference fit are generally mounted so that the ring abuts a shoulder on the shaft or in the housing at one side. At the opposite side, inner rings are normally secured using a lock nut (of series KMT or KMTA). Outer rings are usually retained by a housing end cover. Instead of integral shaft or housing shoulders, it is frequently more convenient to use spacer sleeves or collars between the bearing rings or between a bearing ring and an adjacent component, e.g. a gear. Other methods of axial location which are suitable, above all, for high precision bearing arrangements involve the use of press fits, e.g. in the form of stepped sleeve arrangements. Bearings with tapered bore mounted directly on tapered journals are generally retained by a lock nut on the shaft.
Surface roughness in Ra to DIN 7184; roughness classes N to ISO 1302
51
1
1 Principles of bearing selection and application
Bearing preload Depending on the application, it is necessary to have a positive, or a negative operational clearance in a bearing arrangement. In the majority of highprecision bearing applications a negative operational clearance i.e. a preload is desirable in order to enhance the stiffness of the bearing arrangement, or to increase the running accuracy. The application of a preload is also recommended where bearings are to operate without load, or under very light load and at high speeds. In such cases the preload serves to guarantee a minimum load on the bearing and thus prevents bearing damage resulting from sliding movements. Types of preload Depending on the type of bearing the preload may be either radial or axial. Cylindrical roller bearings can only be radially preloaded and thrust ball bearings can only be axially preloaded. Single row angular contact ball bearings that are
normally subjected to axial preload, are generally mounted together, with a second bearing of the same type in a back-to-back or face-to-face arrangement. The distance between the pressure centres of two angular contact ball bearings is longer when the bearings are arranged back-to-back and shorter when they are arranged face-to-face. This means that the bearings arranged back-to-back can accommodate large tilting moments even if the distance between bearing centres is relatively short. Reasons for bearing preload The main reasons of bearing preload are: ● enhance stiffness ● reduce running noise ● enhance the accuracy of shaft guidance ● compensate for wear and settling (bedding down) processes in operation ● give a long service life. It is easy to understand that preloading bearings have a very positive effect for machine tool spindles.
Adjustment procedures (➔ fig 13 ) Single row angular contact ball bearings are generally adjusted against each other by axial displacement of the inner or outer rings until a certain preload (or a certain clearance) is obtained in the bearing arrangement, (a). Single row angular contact ball bearings that are mounted in sets, (b) and (c), are matched in production so that when they are mounted immediately adjacent to each other, predetermined values of preload are obtained. Cylindrical roller bearings with tapered bore are preloaded by driving the inner ring up on to its tapered seating, (d) and (e); see also mounting instructions from page 79.
With regard to double direction angular contact thrust ball bearings, the spacer sleeve arranged between the shaft washers is dimensioned so that a suitable preload will be obtained once the bearing has been mounted, (f). For high speed bearing arrangements incorporating angular contact ball bearings it is customary to axially preload the bearings by means of springs, (g). This way it is possible to maintain a constant preload in the bearing arrangement throughout the whole range of operating conditions. Specific information concerning preload values is given in the relevant bearing section.
Bearing preload - adjustment procedures Fig 13
(a)
52
(b)
(c)
(d)
(e)
(f)
(g)
53
1
1 Principles of bearing selection and application Preloading by springs The simplest method of applying preload is by springs or spring “package” (➔ fig 14 ). The spring acts on the outer ring of the bearings that are able to be axially displaced. The preload force remains practically constant even when there is axial displacement of the bearing as a result of thermal expansion. Spring loading is a common method of applying preload to the angular contact ball bearings of high speed grinding spindles. The method is not suitable, however, for bearing applications where high stiffness is required, where the direction of load changes, or where undefined shock loads can occur. Specific recommendations for preloading by springs are given in the angular contact ball bearing section.
External axial loads on preloaded bearing sets Angular contact ball bearing sets, and double direction angular contact thrust ball bearings are matched during manufacture to have a predetermined preload once in operation. External axial load may release bearings not supporting the external load from preload (➔ Diagram 2 ). When two bearing rows are preloaded against each other, the same force is exchanged between the two rows. Force will induce a certain displacement in each row, δ. When an external axial load is applied to bearing 1, Ka, deflection of bearing 1 will follow the relevant curve on the abovementioned diagram. At the same time bearing 2 will be subjected to progressively less axial preload which will move from the original static preload value F0 down to the residual force F2. When Ka reaches the value Fb, bearing 2 has no preload left. The force Fb is then the axial external load which releases bearing 2 from preload, the so-called ‘Breakaway’ load.
conditions, and if the spindle, while working is not subjected to strong acceleration, no consequences to operation will result. However, to avoid working beyond the breakaway load it is possible to increase the preload of the bearing sets, or if this is not possible, bearing sets with mixed contact angles may be used. For advice on this, please consult the SKF application engineering service.
Breakaway load varies depending on preload. For angular contact ball bearing sets of two bearings matched back-to-back or face-to-face, for series 2344(00) and BTM the relation between breakaway load and preload is shown in Table 9 page 56. It sometimes happens that the external axial load is greater than the breakaway load Fb. This usually occurs when the spindle is cutting with heavy axial forces and rotating at relatively low speed. In such
External axial loads on preloaded bearing sets Diagram
Bearing 1 2
Load
Deflection on bearing 2
Fig 14
For an application where extremely high speed is required and moderate stiffness is acceptable, preloading should be done through calibrated springs acting against a bearing ring
Deflection on bearing 1
Fb
Breakaway load
K a = external axial load A F1 C F2 δ
F0 = static preload Deflection
0
Displacement of bearing 1 = δ 1
54
2
Displacement of bearing 2 = δ 2
55
1
1 Principles of bearing selection and application
Seals
Preload for customised needs As it is mentioned above, high-precision angular contact ball bearing preload is predetermined during manufacture. In certain special cases it might happen that a different preload is required to achieve the best performances. In these cases it is recommended to use spacers between the bearings with different length. All details covering spacers and spacer reworking are shown in the angular contact ball bearing section.
Bearing positions must be efficiently sealed both outwards and inwards, so that contaminants and damp cannot penetrate, and the lubricant cannot escape, if reliable performance is to be obtained. This is particularly true of bearing arrangements incorporating high-precision bearings where the demands in respect of running accuracy, bearing life and reliability are generally very high. Seals can be of two basic types: noncontacting (non-rubbing) and contacting (rubbing). Contacting seals The following are some examples of contacting seal arrangements (➔ fig 15 ). Because of the friction, contacting seals will raise the temperature of the system and therefore cannot be considered for the majority of machine tool spindles. Thus, in general, contacting seals are used only where low speeds – n dm below 200 000 – are involved and the influence of higher
Guidelines for breakaway load calculation
temperature has no important effects on the spindle working conditions. Because of this, non-contacting seals are almost always used for high-precision bearing arrangements.
1
Non-contacting seals Non-contacting seals are the most commonly used arrangements in machine tools applications, despite their being more difficult to manufacture, more expensive and more complex. Some examples of non-contacting seals are shown in figs 16 and 17 page 58. Among the non-contacting seals, labyrinth seals are the most widely used in spindle applications. They make access to bearings and thus contamination difficult, and prevent cutting fluids from entering the bearing area. The main design features of a labyrinth seal, starting from the external side, are: splashguard, narrow gaps, large drainage chamber(s), and if there is adequate room, further gaps and drainage chambers. The splashguard prevents the fluids gaining access directly to the first gap. The gaps
Contacting seals, examples of application Table
Bearing type & arrangement
Breakaway load vs static preload
Series 70, 72 and 719 CD or ACD, CX or ACX in DB or DF sets
Fb = 2,8 F0
Series 70, 72 and 719 CD or ACD, CX or ACX in TBT or TFT sets (where two bearings are supporting the load)
Fb = 4,2 F0
2344(00), BTM – A and BTM – B series
Fb = 2,85 F0
Ball screw support bearings
as for 70, 72 and 719 series
9
Fig 15
Note: for bearings series or designs not listed above please contact SKF application engineering service
56
57
1 Principles of bearing selection and application prevent most of the fluid proceeding further in. The drainage chambers also serve to reduce the velocity of the fluid arising from the rotation of the shaft. In order to avoid pumping effects inward, the labyrinth components should progressively decrease in diameter inwards from the outside. Machining spirals that can direct the fluid inwards should be avoided. If the spindle is designed to rotate in both directions – clockwise and counter clockwise – spirals have to be avoided. Additional protection is
achieved by creating an overpressure inside the spindle. This is the case when oil spot or oil mist lubrication systems are used. Under severe conditions, an air barrier can be created by blowing air into the labyrinth. It is important that the flow is balanced, so that the dominant flow is outwards. An air barrier can provide a reasonably efficient sealing even with a fairly simple labyrinth design. The following is an example of an efficient sealing system.
Non-contacting seals, examples
Preventive stages The sealing system can be divided into the following preventive stages (➔ fig 18 ). 1 Direct access to the labyrinth of fluid washing over the spindle housing is prevented. 2 Splashguard, designed as a labyrinth, together with the housing cover, throws
fluids outward. Both the splashguard and the housing cover are provided with one or several annular grooves to direct the fluid. When positioned on a rotating body, the grooves have little influence during rotation. 3 Gap with a height of 0,1 – 0,2 mm. 4 Groove or grooves on the shaft to direct the fluid under non-rotating conditions.
Labyrinth sealing system, example Fig 16
Fig 18
2
1
9
3 4 5 7
8
11
12
Fig 17
6
10
58
59
1
1 Principles of bearing selection and application 5 Large drainage chamber where the velocity of the fluid is reduced. The chamber should be relatively large as the amount of fluid at this stage can be important. 6 Drainage using a large outlet area around 250 mm2, so that no fluid stays inside the chamber (5). 7 Labyrinths with gap heights of 0,2 – 0,3 mm. 8 Chamber for fluid retardation. 9 Collector to guide the fluid to the lower side and prevent it from penetrating further. 10 Drainage using an area of 100 – 150 mm2. 11 Chamber with collector and drainage as in steps (8) – (10). Only very little fluid should be present here and a drainage area of around 50 mm2, should be adequate. 12 Gap with a height of about 1 mm to avoid capillary action.
This design is rather complex and more costly than conventional labyrinths, however, if the environmental conditions are severe, a very efficient sealing should be considered. The service life of the spindle will otherwise suffer, and downtime and replacement costs can be very high. A sealing system that takes up considerable space axially is favourable, as large drainage areas and collectors can be designed, thus improving sealing efficiency. However, the larger the space taken axially, the longer the overhang from the front bearing and the cutting force position, thus making the spindle radially less rigid.
Retaining covers Retaining covers and their securing screws may be a source of deterioration in bearing accuracy. If the wall thickness between the bearing seating and the screw holes is too small, and/or the screws are tightened too hard, the outer ring raceway may be deformed. Bearings of the lightest ISO Dimension Series, 19 may be more seriously affected than the thicker rings of bearings belonging to ISO Dimension Series 10 or above. It may be advantageous to use a large number of small diameter screws. Using only 3 or 4 screws should be avoided as such a small number of tightening points
may produce lobes in the housing bore diameter. This can produce changeable friction torque, noise and unstable preload (when angular contact ball bearings are used). For spindles where the design is complex, space is limited, only a few screws can be used and thin-section bearings are used, an FEM (finite element) analysis may be recommended to accurately monitor deformation. In addition, the play between the housing and the front cover should be checked. A guideline value may fall between 10 and 15 µm per 100 mm housing bore diameter (or bearing outside diameter) (➔ fig 19 ).
Checking the play between the housing and the front cover Fig 19
øD
10–15 µm/100 mm øD
60
61
1
1 Principles of bearing selection and application
Lubrication and maintenance General
Grease lubrication
The choice of lubricant and lubrication method for a particular application depends primarily on the operating conditions, e.g. permissible temperatures or operating speeds, but may also be dictated by the lubrication of adjacent components (e.g. gear wheels). For an adequate lubricant film to be formed between the rolling elements and raceways, only a very small amount of lubricant is required. With very small quantities, the hydrodynamic friction losses are small and operating temperatures can be kept down. Such minimal lubricant quantity can reliably be obtained using grease, and this method of lubrication is also becoming popular for spindle bearing arrangements. However, where speeds are very high, the bearings should be lubricated with oil, as the service life of grease is too short under such conditions.
Grease lubrication may be used for all bearings shown in this catalogue. The use of grease means that bearing arrangement design can be relatively simple because grease is more easily retained at the bearing position than oil, and it also contributes to sealing the bearing against contaminants and damp. Bear in mind that the grease applied should always be free from contaminants. In most cases a lithium grease with a mineral oil base is suitable for highprecision bearings. Where demands for speed, temperature and service life are high, the use of bearing greases based on synthetic oils, e.g. the SKF grease LGLT 2 which has a diester oil base, have proved beneficial. The lubrication of a bearing arrangement with a good quality grease in suitable quantity, permits relatively high speed operation without an excessive rise in temperature, compared with some other methods of lubrication. Grease lubricated bearing arrangements are therefore suitable for a wide speed range.
Grease selection Lithium base greases with a mineral oil base are particularly suitable for the lubrication of rolling bearings and may also be used for high-precision bearings. These greases adhere well to the bearing surfaces and can generally be used in the temperature range –30 to +110 °C. This is sufficient for most applications. In cases involving special features (e.g. operating temperature below 50 °C or above 100 °C, very high or very low bearing speed, bearings subject to heavy load or shock loads, water resistance, compatibility) the following criteria can be adopted. First select consistency and base oil viscosity, check EP additives needed, then check for additional requirements (➔ Table 1 ). The method of selecting the required oil viscosity is explained in the section “Lubrication and maintenance” in the SKF General Catalogue or the SKF Interactive Engineering Catalogue. The selection process is based on the elasto-hydrodynamic theory of lubrication (EHL). It is assumed that there is an
Consistency selection Table Consistency
62
abundant supply of oil to the contact to be lubricated (fully flooded inlet conditions). This is usually correct for oil lubrication, but for grease lubrication the situation can be quite different. In most grease lubricated bearings there is only a very minute amount of lubricant available in the actual contact between the rolling element and the raceway. This lubrication mode is called Starved Lubrication. The consequence of this is that with grease lubrication the lubricant film thickness is often much less than with oil lubrication and a correction has to be made when calculating the grease base oil viscosity. From practical experience the following guidelines can be given. If the calculation leads to a viscosity of more than 500 mm2/s at 40 °C, then consider applying a correction factor for base oil viscosity of 0,5 or smaller. Greases with very high base oil viscosities should only be used in very special applications (typically very slowly rotating rolling bearings with continuous lubrication). If the calculated viscosity is lower, do not apply a correction
1
Applications
NLGI 2 grade
Normal applications
NLGI 3 grade
Large bearings, vibration, high ambient temperatures, vertical shafts
NLGI 1 grade
Low ambient temperatures, oscillating applications
63
1
1 Principles of bearing selection and application factor. If the required base oil viscosity is not high (typically below 20 mm2/s at operating temperature), consider multiplying the calculated base oil viscosity by a factor 2. Following from this empirical rule, selection of too high a grease base oil viscosity will impede the lubricant’s access to the bearing contacts. And with increasing base oil viscosity, oil bleed also reduces. So with a very high base oil viscosity, the lubricant film actually becomes thinner instead of thicker. Conversely, if the calculated oil viscosity is low, the lubricant film thickness can be increased by selecting a grease with a higher than calculated base oil viscosity. Greases with EP additives may be used if bearings are subjected to heavy loads (e.g. C/P < 5), shock loads occur frequently, or if frequent start-up and shutdown occurs during the working cycle. Use EP additive lubricants only if necessary. Certain EP additives are not compatible with some cage materials. Please consult the SKF application engineering service for further details.
Grease quantities Bearings operating at high speeds, where it is desirable to keep the operating temperature low to ensure long grease life should be lubricated with small quantities of grease. In machine tool applications that mostly run at high speed the quantity should be lower than 30 % of the free space in a bearing. Freshly greased bearings should be run at low speed during a running-in phase so the grease will be evenly distributed within the bearing and excess grease can be ejected. If this running-in phase is neglected, risk of temperature peaking can lead to bearing failure later on. From experience in the field, the most common filling quantities are about 10 % filling grade. Suggested quantities for high-precision bearings in machine tool applications are given in Table 2 . Pre-greased angular contact ball bearings may be delivered on request with the proper grease type and filling grade. Please consult SKF for availability and technical details.
Table
2
1
Bearing Grease charge for bearings of series bore diameter 719 CD 70 CD 72 CD 719 CE 70 CE N 10 NN 30 NNU 49 BTM – A 2344(00) BSA 2 BSD 719 ACD 70 ACD 72 ACD 719 ACE 70 ACE BTM – B BSA 31) 719 CX 70 CX 72 CX 719 ACX 70 ACX 72 ACX mm
cm3
8 9 10 12 15 17
– – 0,04 0,04 0,07 0,08
0,05 0,06 0,08 0,09 0,13 0,18
– – 0,12 0,15 0,22 0,3
– – – – – –
– – – – – –
– – – – – –
– – – – – –
– – – – – –
– – – – – –
– – – – – –
– – – 0,3 0,4 0,6
– – – – – –
20 23,8 25 30 35 38,1
0,15 – 0,18 0,21 0,31 –
0,3 – 0,34 0,53 0,66 –
0,46 – 0,57 0,83 1,2 –
0,16 – 0,18 0,21 0,32 –
0,34 – 0,4 0,57 0,71 –
– – – – – –
– – 0,9 1,1 1,4 –
– – – – – –
– – – – – –
– – – 1,9 2,3 –
0,8 – 1 1,5 2 –
1 1,4 1,4 1,4 1,8 3,8
40 44,4 45 50 55 60
0,48 – 0,54 0,58 0,83 0,9
0,8 – 1,1 1,2 1,7 1,8
1,5 – 1,8 2,1 2,6 3,3
0,49 – 0,55 0,59 0,85 0,92
0,86 – 1,1 1,2 1,55 1,65
1,2 – 1,3 1,5 1,8 2
1,7 – 1,9 2,1 2,6 2,8
– – – – – –
– – – – – 3,2
2,7 – 3,2 3,5 4,5 4,8
– – – – – –
3,8 (1,6)2) 5 5 (1,6)2) 5 – –
65 70 75 80 85 90
0,95 1,5 1,7 1,7 2,4 2,5
1,9 2,7 2,8 3,7 3,9 5
4,1 4,6 5 6 7,2 9
0,98 1,6 1,7 1,8 2,5 2,6
1,75 2,5 2,7 3,6 3,8 5
2,1 2,6 2,8 3,4 3,5 4,1
3 3,8 4 4,9 5,1 5,9
– – – – – –
3,3 4,4
5,1 6 6,4 7,7 8,1 9,6
– – – – – –
– – – – – –
95 100 105 110 120 130
2,6 3,5 3,7 3,8 5,1 6,8
5,2 5,4 6,8 8,5 9 14
11 13 16 18 22 –
2,7 3,6 3,8 3,9 5,3 –
5,2 5,5 – – – –
4,3 4,5 5,3 6,1 6,7 –
6,2 6,5 7,6 8,8 9,6 12
4,5 7 7,3 9 11
9,6 12 17 25,5
10 11 12 14 15 19
– – – – – –
– – – – – –
140 150 160 170 180 190
7,2 11 11 12 18 19
15 18 22 28 37 38
– – – – – –
– – – – – –
– – – – – –
– – – – – –
17 20 22 29 34 36
15 19 21 24 30 31
– – – – – –
27 31 36 43 51 53
– – – – – –
– – – – – –
200 220 240 260 280
27 28 31 – –
51 67 72 – –
– – – – –
– – – – –
– – – – –
– – – – –
42 76 83 140 155
39 62 68 122 128
– – – – –
57 – – – –
– – – – –
– – – – –
1) 2)
6,4 6,7 8,9
Values for BSA 3 series are 1,7 times the values of BSA 2 series Values in brackets refer to smaller outside diameter where two different bearings have the same bore diameter (e.g. BSD 4072 C and BSD 4090 C)
Grease charges ➤
64
65
1 Principles of bearing selection and application Grease service life Several methods are used to calculate the relubrication interval for grease lubricated bearings. However there are several important factors influencing the grease life, many of which are difficult to estimate. It is extremely complex to calculate precisely how long the grease can survive in a given
application depending on the actual conditions. It is better to talk of grease life estimation, and the following data assists in making the best estimate. The graph (➔ Diagram 1 and Tables 3 and 4 ) shows the theoretical relubrication interval tf for high-precision bearings in various executions. The angular contact ball bearing
curves refer to single bearings, so data for matched sets should be reduced depending on the arrangement as per Table 3 . For hybrid bearings the estimated grease service life can be obtained by multiplying the calculated value for the all-steel bearing by the factor given in Table 4 . Table Bearing design
Preload class Light Medium
1
3 n dm
A
T
0,5
3
3
0,7
3,5
3
1
3
3
1,5
2,8
2,5
Table
4
Table
5
C
Heavy millions
A Set of 2 Set of 3 Set of 4 More
Codes:
0,8 0,7 0,7 0,55 0,65 0,45 Contact SKF
T, BTM series 1 B As A
– –
0,55 0,35 0,25
0,5 As A
3
A = Angular Contact Ball Bearings; C = Cylindrical Roller Bearings; T = Angular Contact Thrust Ball Bearings; B = Ball Screw Support Bearings. Grease relubrication intervals guidelines Diagram
1
Factors to calculate grease relubrication interval depending on bearing arrangement
Ceramic material effect
Relubrication interval (hours) 100 000 A 15°
Guidelines on correction factors for relubrication interval estimation A 25° 10 000 Shaft position correction factor C1
Vertical 0,5
Horizontal 1
Bearing load correction factor C2
C/P > 20 1
C/P > 10 0,7
Reliability correction factor C3
L1 0,37
L50 2
Air flow-through correction factor C4
Low 1
Moderate 0,3
Strong 0,1
Damp & dust correction factor C5
Low 1
Moderate 0,5
High 0,3
Very high 0,1
Temperature correction factor C6
40 °C >1
55 °C >1
70 °C 1
85 °C 0,5
C N 10
1 000
T&B
C NN 30
100 0,1
0,15
0,2
0,3
0,5
0,7
1
1,5
C/P > 8 0,5
C/P > 5 0,3
C/P > 2 0,2
C/P >1 0,1
100 °C 0,25
Speed factor, n dm (millions)
66
67
1 Principles of bearing selection and application The basic conditions for which Diagram 1 page 66 has been drawn up are: 1) bearings are mounted on horizontal shafts 2) bearing operating temperature does not exceed 70 °C 3) a good quality lithium base grease is used 4) a relubrication interval at the end of which 90 % of the bearings are still reliably lubricated (L10 life). The data from the graphs must then be multiplied by several factors related to the specific application data (➔ Table 5 page 67). The relubrication interval then becomes Trelub = tf × C1 × C2 × … × Ci Other conditions such as the presence of water, cutting fluids, vibration etc may affect grease life. Machine tool spindles often operate with working conditions that are not constant. If the speed spectrum is known and the lubrication interval for each speed is estimated, a total lubrication interval can be calculated with the following equation: tf tot =
Changing the grease type Where an alternative grease is considered for a certain application, its compatibility with the grease currently used should be checked first. Tables 6 and 7 indicate compatibility of base oil and thickener type. Before applying a new grease, the old one should be completely removed. Also, for a certain period during the early stages of running, regular checks, grease replacement and close monitoring of the bearings need to be made. The above is based on grease composition and is an indication only, so in order to be certain, individual testing may be required. The above procedure does not apply to PTFE thickener or silicone based greases for which bearings should be thoroughly washed (using appropriate solvents) before the new grease is applied. Always check that the new grease is suitable for the application.
Table
6
Mineral oil
Ester oil
Polyglycol
Siliconemethyl
Siliconephenyl
Polyphenylether
Mineral oil
+
+
−
−
+
O
Ester oil
+
+
+
−
+
O
Polyglycol
−
+
+
−
−
−
Silicone-methyl
−
−
−
+
+
−
Silicone-phenyl
+
+
−
+
+
+
Polyphenylether
O
O
−
−
+
+
+ = compatible, − = incompatible, O = individual testing required
Compatibility of base oil types
Compatibility of thickeners Table
7
Li soap
Ca soap
Na soap
Li Ca Na Ba Al Clay Polyurea complex complex complex complex complex soap soap soap soap soap
+
O
–
+
–
O
O
–
O
O
100 ∑ (ai/tfi)
where: tf tot = total lubrication interval ai = part of the total cycle time at speed ni, %; tfi = lubrication interval at speed ni.
Li soap Ca soap
O
+
O
+
–
O
O
–
O
O
Na soap
–
O
+
O
O
+
+
–
O
O
Li complex soap
+
+
O
+
+
O
O
+
–
–
Ca complex soap
–
–
O
+
+
O
–
O
O
+
Na complex soap
O
O
+
O
O
+
+
–
–
O
Ba complex soap
O
O
+
O
–
+
+
+
O
O
Al complex soap
–
–
–
+
O
–
+
+
–
O
Clay
O
O
O
–
O
–
O
–
+
O
Polyurea
O
O
O
–
+
O
O
O
O
+
+ = Compatible, – = Incompatible, O = Individual testing required
68
69
1
1 Principles of bearing selection and application Running-in of greased bearings A grease-lubricated bearing will initially run with a rather high frictional moment, and if the speed is high, the temperature rise can be considerable and excessive. The high frictional moment is due to churning of the grease, and it takes some time for the excess grease to work its way out of the contact zone and be forced away from the raceways. This can be minimized by applying a small quantity of grease and distributing the grease evenly on both sides of the bearing. Where possible, the adoption of spacers in between two adjacent bearings is also beneficial. The time required to stabilize temperature depends on a number of factors – the type of grease, the grease charge, how the grease is applied to the bearings, the bearing type and internal design, and the running-in procedure. When properly run-in, the bearings work with minimal lubricant, giving the lowest frictional moment and temperature. The grease remaining at the sides of the raceways will act as a reservoir and the oil will bleed into the raceways, ensuring a safe lubrication for a long period of time. Running-in can be done in several ways. The most common is to increase the speed in stages, waiting for the bearing temperature to stabilize before moving on to the next step. It is advisable to go one step more than the operating speed of the system, as this will ensure a lower temperature rise while operating. The temperature should be monitored during running-in to avoid large peaks which may later be detrimental to the grease life. As a general recommendation, the absolute temperature should be limited to approximately 60 – 65 °C. If running-in
is done automatically on a test machine, it is preferable to set the machine with temperature alarms which will stop the spindle if the temperature rise exceeds fixed limits. Although easy to handle, automatic machines operating on time steps only, do not monitor the temperature that may go beyond acceptable levels. Though widely used, the above procedure is time-consuming. Several hours may be required for a medium high spindle speed, as each step may take between 30 minutes and 1 – 2 hours before temperature stabilises. Total time for completing the running-in could be 8 – 10 hours. The running-in time can be shortened considerably by using a few steps only and by starting at a speed approximately equal to 20 – 25 % of the bearing catalogue speed. This can significantly reduce the number of steps, but at each step the temperature increase may be very rapid. The temperature of the bearings must be carefully monitored with this procedure, and if possible should be measured on the bearing outer ring, using an automatic switch off when the temperature exceeds the above set limits. After the outer ring has cooled down 5 – 10 °C the spindle is restarted at the same speed. The same procedure may have to be repeated several times, but the cycle time is just a few minutes. When a temperature peak, lower than the alarm limit, has been reached, the temperature will decrease rather rapidly and the bearing is then run-in at that particular speed. Wherever possible and regardless of the procedure chosen, running-in should involve placing the spindle in rotation both clockwise and anti-clockwise.
Oil lubrication General Several methods of oil lubrication are available, which differ in specific characteristics. Oil lubrication is therefore recommended for many applications and can be adapted to suit the actual operating conditions and particular machine design. The most commonly used methods of oil lubrication are described below. For spindle bearing arrangements, the high operating speeds and requisite low operating temperatures generally necessitate the use of circulating oil lubrication with oil cooling, or the oil spot method. Depending on the
method chosen, the following factors play an important part: ● quantity and viscosity of the oil ● speed and hydrodynamic friction loss which is a function of the speed ● permissible bearing temperature
1
The relationships between oil quantity, friction and bearing temperature are shown in Diagram 2 . Where there is insufficient oil (region A), complete separation of rolling elements and raceways will not be achieved. Metallic contact will lead to increased friction and temperature, and finally to bearing wear. A cohesive, load-carrying oil film can only be formed if a greater quantity
Information on oil quantities for special applications may be obtained from SKF applications engineers.
Bearing temperature and frictional loss as a function of oil quantity Diagram
2
Bearing temperature, T
Frictional losses, Wf
A
B
C
D
E Oil quantity
70
71
1 Principles of bearing selection and application of oil is available (region B). Here the condition is reached where friction and consequently temperature, are at a minimum. A further increase in oil quantity (region C) will result in increases in friction and temperature only until the quantity is such that an equilibrium is achieved between heat generation and heat loss, after which (region D) there is little change in temperature with oil quantity. If even more oil is added, the cooling effect predominates and the temperature starts to fall (region D-E). The conditions obtained with oil spot lubrication correspond to those of region B, and the conditions obtained with circulating oil lubrication where the oil is also cooled correspond to those of region E. Common methods of oil lubrication Several methods of oil lubrication are available, which differ in specific characteristics. Oil bath lubrication Oil bath lubrication is the simplest method of oil lubrication. The oil, which is picked up by the rotating components of the bearing, is distributed within the bearing and then flows back to the oil bath. Oil bath lubrication is particularly suitable for low speeds and enables design of relatively simple and economic bearing arrangements. At high speeds however, the bearings are supplied with too much oil, increasing friction within the bearing and causing the operating temperature to rise. Circulating oil lubrication With circulating oil lubrication, the lubricating oil is pumped to a position above the bearing where it runs down through the bearing. After the oil has passed through the bearing it is filtered and, if required, cooled before being returned to the bearing.
Cooling the oil enables the operating temperature of the bearing to be kept at low level. Oil drop lubrication In this method, the bearing is supplied at given intervals with an accurately metered quantity of oil. The quantity supplied may be relatively small, so frictional losses at high speeds are small. However, it is not certain that the oil will penetrate the bearing at high speeds. Oil jet lubrication In the oil jet method a jet of oil under high pressure is directed at the side of the bearing. The velocity of the oil jet must be high enough (at least 15 m/s) so that at least some of the oil will penetrate the turbulence surrounding the rotating bearing. This method is particularly efficient and is often used for high-speed bearing arrangements. Oil mist lubrication In oil mist lubrication, finely divided oil droplets are supplied to the bearing in a stream of compressed air. The air passing through the bearing serves to cool it and produces a slight excess pressure that enhances sealing. Minimum quantities of oil can be used however; in practice it is difficult to supply the bearing reliably with the very small quantities of oil involved. Oil mist is fairly costly and less and less accepted because polluting the immediate surroundings of the machine. Oil spot (minimal) lubrication With the oil spot method very small accurately metered quantities of oil are directed at each individual bearing by compressed air. The minimum quantity enables bearings to operate at lower
temperatures than any other method of lubrication. The oil is supplied to the leads by a metering unit, it coats the inside surface of the leads and “creeps” along them. It is injected to the bearing via a nozzle. The compressed air serves to cool the bearing and also produces an excess pressure in the bearing arrangement that prevents contaminants from entering. The speed rating for oil lubrication given in the product tables apply to oil spot lubrication. When using the circulating oil, oil jet and oil spot methods it is necessary to ensure that the oil flowing from the bearing can leave the arrangement by adequately dimensioned ducts.
The amount of oil required for circulating oil lubrication with additional cooling can be calculated approximately using
Circulating oil lubrication with additional cooling This method is suitable for high-speed bearings provided an efficient oil cooling system and proper drainage ducts at both sides of the bearing are in place. Cooling the oil helps keeping bearing temperatures down, although the large quantities of oil and the increased frictional losses associated with the lubricant mean that more power is needed. Circulating oil lubrication with cooling system requires pumps and cooling devices and places considerable demands on the sealing. It is therefore relatively expensive.
The oil quantities determined using the above equation can be used as guideline values when selecting pumps and cooling arrangements. They are valid provided that the operating temperature of the shaft does not exceed ambient temperature by more than 30 °C; the bearing outer ring temperature may be 5 °C higher. With higher temperatures the formula may give wrong values, as the transfer of heat from the shaft is not considered. For accurate analysis, computer programs are available. Please consult SKF for details. Table 8 gives guidelines for oil flow rate.
Table Bearing bore diameter d over incl.
Oil flow rate
mm
l/min
– 50 120
50 120
low
0,3 0,8 1,8
Q = (M0 + M1) (n π/∆T)10−6 where Q = requisite oil quantity, l/min M0 = load-independent frictional moment, see SKF General Catalogue, Nmm M1 = load-dependent frictional moment, see SKF General Catalogue, Nmm n = bearing speed, r/min ∆T = permissible increase in temperature of lubricating oil (difference between oil temperature before and after the bearing position), °C
8
high
1 3,6 6
Guidelines for oil flow rate
72
73
1
1 Principles of bearing selection and application Oil spot lubrication Oil spot lubrication enables reliable bearing lubrication to be achieved using extremely small quantities of oil. Lower operating temperatures or higher speeds can be reached using this method of oil lubrication. Guideline values for the oil quantity to be supplied to a bearing can be obtained from Q = q d B × 10−2 where Q = oil quantity, mm3/h d = bore diameter of bearing, mm B = bearing width, mm and q is a factor, see explanation below (➔ Table 9 ). The quantity varies depending on bearing type and design and this is determined by using different values of the factor q, i.e. should be 1 – 2 for roller bearings, and 2 – 5 for ball bearings. When speed is very high and angular contact ball bearings are used, the factor q will be much higher because of the pumping effect of angular contact ball bearings. For such cases a value of q between 10 and 20 should be used. Individual testing is always necessary however to optimise the conditions. Different bearing designs show varying sensitivity to oil quantity change, i.e. roller bearings are very sensitive to oil inlet changes while for ball bearings, the quantity can be
changed substantially without any major effect on the bearing temperature rise. Temperature rise and reliability with oil spot method depend to a large extent on the lubrication interval, i.e. the time in between two shots from the oil spot lubricator. Generally the lubrication interval is determined by the oil flow rate generated by each injector and the oil quantity supplied per hour. This interval can vary from one minute to one hour, with the most common interval being 15 – 20 minutes. Pipes from the lubricator should be long enough, normally 1 – 5 m in length depending on the time interval between two subsequent shots. The air pressure should be 0,2 – 0,3 MPa, but must be increased when pipes are long to compensate for the pressure drop along the pipes. To keep rise in temperature at the lowest possible level, good drainage must be designed. With horizontal spindles it is relatively easy to arrange drainage ducts at each side of the bearings involved. Where bearings with lubrication grooves are used, a drainage duct for the annular groove must also be considered. For vertical shafts, the oil passing the upper bearings must be prevented from reaching the lower bearings which otherwise will receive too much lubricant. Drainage, together with a sealing device must be incorporated at the lower side of each bearing. An efficient seal should also be provided at the spindle nose to prevent lubricating oils reaching the workpiece.
Table
9
1
Bore code
q=1
q=2
q=3
q=5
q = 10
q = 15
q = 20
8 9 00 01 02 03
0,56 0,63 0,80 0,96 1,35 1,70
1,12 1,26 1,60 1,92 2,70 3,40
1,68 1,89 2,40 2,88 4,05 5,10
2,80 3,15 4,00 4,80 6,75 8,50
5,60 6,30 8,00 9,60 13,50 17,00
8,40 9,45 12,00 14,40 20,25 25,50
11,20 12,60 16,00 19,20 27,00 34,00
04 05 06 07 08 09
2,40 3,00 3,90 4,90 6,00 7,20
4,80 6,00 7,80 9,80 12,00 14,40
7,20 9,00 11,70 14,70 18,00 21,60
12,00 15,00 19,50 24,50 30,00 36,00
24,00 30,00 39,00 49,00 60,00 72,00
36,00 45,00 58,50 73,50 90,00 108,00
48,00 60,00 78,00 98,00 120,00 144,00
10 11 12 13 14 15
8,00 9,90 10,80 11,70 14,00 15,00
16,00 19,80 21,60 23,40 28,00 30,00
24,00 29,70 32,40 35,10 42,00 45,00
40,00 49,50 54,00 58,50 70,00 75,00
80,00 99,00 108,00 117,00 140,00 150,00
120,00 148,50 162,00 175,50 210,00 225,00
160,00 198,00 216,00 234,00 280,00 300,00
16 17 18 19 20 21
17,60 18,70 21,60 22,80 24,00 27,30
35,20 37,40 43,20 45,60 48,00 54,60
52,80 56,10 64,80 68,40 72,00 81,90
88,00 93,50 108,00 114,00 120,00 136,50
176,00 187,00 216,00 228,00 240,00 273,00
264,00 280,50 324,00 342,00 360,00 409,50
352,00 374,00 432,00 456,00 480,00 546,00
22 24 26 28 30 32
30,80 33,60 42,90 46,20 52,50 60,80
61,60 67,20 85,80 92,40 105,00 121,60
92,40 100,80 128,70 138,60 157,50 182,40
154,00 168,00 214,50 231,00 262,50 304,00
308,00 336,00 429,00 462,00 525,00 608,00
462,00 504,00 604,50 693,00 787,50 912,00
616,00 672,00 858,00 924,00 1 050,00 1 216,00
34 36 38 40 44 48
71,40 82,80 87,40 102,00 123,20 134,40
142,80 165,60 174,80 204,00 246,40 268,80
214,20 248,40 262,20 306,00 369,60 403,20
357,00 416,00 437,00 541,00 616,00 672,00
714,00 828,00 874,00 1 020,00 1 232,00 1 344,00
1 071,00 1 242,00 1 311,00 1 530,00 1 848,00 2 016,00
1 428,00 1 656,00 1 748,00 2 040,00 2 464,00 2 688,00
Factor q for oil spot lubrication and guidelines for angular contact ball bearings series 70
74
75
1 Principles of bearing selection and application Position of the oil nozzles Oil nozzles should be correctly positioned to avoid difficulties for the oil to enter the contact area between rolling element and raceway and so that it does not impinge on the cage. Table 10 gives the values of the diameters (from the shaft axis) where oil injection should take place for the most common bearing designs and series (➔ fig 1 ). The data shown in Table 10 refers to bearings with their standard cage designs. For bearings fitted with other cages or bearing types not shown, SKF should be consulted. Lubricating oils For the lubrication of high-precision bearings, high quality lubricating oils without additives should be considered. The requisite viscosity of the oil can be
determined following the recommendations in the SKF Interactive Catalogue and is essentially a function of bearing size, speed and operating temperature. The intervals at which the oil should be changed when using the oil bath, circulating oil and oil jet methods depend mainly on the operating conditions and the quantities of oil involved. Further information may be found in the SKF Interactive Catalogue, or obtained on request from the oil suppliers. With oil spot lubrication systems there is no restriction as to oil type, and the oil viscosity may be much higher than for oil mist systems. Oils with 40 up to 100 mm2/s viscosity at 40 °C are typically used, as are oils with EP additives that are preferable especially with roller bearings. Where oil drop, oil mist or oil spot lubrication is applied, the oil is “lost”, i.e. it is only supplied to the bearing once.
Fig
d
dn
d
1
dn
Table 10 Bore code
Bore diameter
Oil nozzle position dn for bearings of series 719 CD, 719 CE, 70 CD, 70 CE, 719 ACD 719 ACE 70 ACD 70 ACE 719 CX 70 CX 719 ACX 70 ACX
mm
mm
8 9 00 01 02 03
8 9 10 12 15 17
– – 14,8 16,8 20,1 22,1
– – – – – –
13,6 15,1 16,3 18,3 21,8 24,0
04 05 06 07 08 09
20 25 30 35 40 45
26,8 31,8 36,8 43,0 48,7 54,2
26,8 31,8 36,8 43,0 48,7 54,2
10 11 12 13 14 15
50 55 60 65 70 75
58,7 64,7 69,7 74,7 81,7 86,7
16 17 18 19 20 21
80 85 90 95 100 105
22 24 26 28 30 32 34 36 38 40 44 48 52 56
1 72 CD, 72 ACD 72 CX 72 ACX
NNU 49
NN 30, N 101)
– – – – – –
– – 18,2 20,0 23,0 25,9
– – – – – –
– – – – – –
28,7 33,7 39,7 45,7 51,2 56,7
28,8 33,8 40,0 46,0 51,5 57,2
31,1 36,1 42,7 49,7 55,6 60,6
– – – – – –
– 40,5 47,6 54,0 60,0 66,4
58,7 64,7 69,7 74,7 81,7 86,7
61,7 68,7 73,6 78,6 85,6 90,6
62,2 69,7 74,7 79,7 86,7 91,7
65,6 72,6 79,5 86,5
– – – –
71,4 79,8 85,0 89,7
96,5
–
103,5
91,7 98,6 103,6 108,6 115,6 120,6
91,7 98,6 103,6 108,6 115,6 120,6
97,6 102,6 109,5 114,5 119,5 126,5
98,7 103,7 110,6 115,6 120,6 –
103,5 111,5 117,5 124,4 131,4 138,4
– – – – 113,8 119,0
111,4 116,5 125,4 130,3 135,3 144,1
110 120 130 140 150 160
125,6 137,6 149,5 159,5 173,5 183,5
125,6 137,6 – – – –
133,5 143,5 157,5 167,4 179,4 191
– – – – – –
145,9 158,2 170,7 – – –
124,0 136,8 147,0 157,0 169,9 179,8
153 162,9 179,6 188 201,7 214,4
170 180 190 200 220 240 260 280
193,5 207,4 217,4 231,4 251,4 271,4 – –
– – – – – – – –
205,8 219,7 229,7 243,2 267,1 287 – –
– – – – – – – –
– – – – – – – –
189,8 203,5 213,0 227,0 247 267,0 294,5 313,5
230,8 248,9 258,9 275,3 302,4 322,4 355,2 375,3
Oil nozzles position
1)
For N 10 series equipped with TNHA cages please contact the SKF application engineering service
Oil nozzle position for different bearing design ➤
76
77
1 Principles of bearing selection and application
Maintenance Bearings storage Bearings can be stored in their original packages for years, provided relative humidity in the storage room does not exceed 60 % and there are no great fluctuations in temperature. Humidity and temperature must be controlled during storage, handling and transport if at all possible, particularly in tropical areas. Bearings should be kept in a vibration-free dry place where the relative humidity and temperature are reasonably constant. Bearings that are not stored in their original packages should be well protected against corrosion and contamination. Large rolling bearings should only be stored lying down, and preferably with support for the whole extent of the side faces of the rings. If kept in a standing position, the weight of the rings and rolling elements can give rise to permanent deformation because the rings are relatively thin-walled.
78
Lubricant storage Most materials including oils and greases deteriorate with time. The art of good storage practice is to have materials always available when required, and to ensure stock turnover so that lubricants are used before any significant performance loss has occurred. Lubricant properties may vary considerably during storage due to exposure to air/oxygen, temperature, light, water and moisture, oil separation and presence of particles. The recommended maximum storage time is 2 years for greases and 10 years for lubricating oils, assuming reasonable stock keeping practices and protection from excessive heat and cold are followed. A lubricant in excess of the recommended shelf life is not necessarily unsuitable for service but it is advisable to check if it still meets the product requirements/specifications.
Dismounting and mounting Dismounting Proper maintenance of spindles is essential to their performance, and replacing the bearings in the correct way using the right tools is a major part of that maintenance. Before disassembly begins, a suitable working area should be prepared and the proper tools made available. The working area should be clean and away from areas where cutting and grinding operations take place. No traverses should pass over the working place. It is best to use a separate room if possible, one that is temperature controlled, dedicated to handling of accurate components and easy to keep clean. Tool requirements differ depending on spindle design, but use of the correct tools makes the work easier and more efficient, and avoids damaging the components. Information on mounting and dismounting tools can be found in the catalogue SKF Maintenance and Lubrication Products. A detailed drawing of the spindle should also be available.
Dismounting a spindle with bearings arrangement 70 CD/TBT at the work side and NN 30 K at the drive side. To illustrate the procedure for replacing the bearings of a spindle, one of the most common spindle designs is chosen here as an example. The spindle is a cartridge type and thus the complete spindle can be easily removed from the machine. The spindle is belt driven and the pulley is fitted directly at its rear. At the work side the spindle is equipped with a set of three angular contact ball bearings of series 70 ACD. At the drive side is a cylindrical roller bearing of series NN 30 K. This bearing is mounted on a tapered seating. The spindle has a flange at the nose that is common for lathe and milling spindles. Thus the bearings have to be removed and fitted from the drive side (➔ fig 1 page 80). The bearings are lubricated with grease – the most common type of lubrication today. Clean the outside of the spindle before placing it on the worktable.
79
1
1 Principles of bearing selection and application Fig
1
Spindle with bearing arrangement 70 CD/TBT at the work side and NN 30 K at the drive side
Removing drive side bearings Place the spindle on V-blocks or another arrangement, depending on external design of the spindle, for easy handling. Unscrew the rear side nut (1), remove the pulley (2) with the keys (3) and the sealing device (4). Remove the housing cover (5) (➔ fig 2 ). As the drive side bearing has a tapered bore and the shaft is provided with an oil duct and oil groove for this bearing, it is easily removed by using a hydraulic pump. (➔ fig 3 ).
1 Connect the nipple to the oil duct and then connect the oil pump to the nipple and tighten the release knob on the pump. 2 Put the rear side nut on the spindle to prevent the bearing falling off the spindle when released. 3 Inject the oil. The bearing inner ring will be released when the pressure is about 20 MPa. The spacer (6) (➔ fig 4 page 82) is taken away after removal of the shaft. If the spindle is not provided with an oil duct and groove, removal of the bearing must wait until the shaft has been withdrawn from the housing.
Removing the drive side bearing: connect the nipple to the oil duct in the shaft Fig
5
4
3
2
2
Removal of nut, pulley, sealing device and housing cover
Fig
3
1
SKF pump 729124 for pressure up to 100 MPa
80
81
1
1 Principles of bearing selection and application Withdrawal of the shaft from housing. The spindle is equipped with a reinforced labyrinth seal at the work side. Remove the external component (7) (➔ fig 5 ). Normally some force is necessary to withdraw the shaft from the cartridge, as in most cases the work side bearings have a certain interference fit. The required withdrawal force expressed in N for a set of three bearings can be estimated at 20 times the outside diameter of the bearing expressed in mm. Example: Bearing set
7020 ACD/P4ATBTB having an outside diameter of 150 mm will require a withdrawal force of approximately 20 × 150 = 3 000 N. If the bearings are to be used again, e.g. after being relubricated, great care must be taken to avoid damaging them during disassembly of the spindle. Blows to the shaft as a method of withdrawal must be avoided as this can easily create serious indentations on the raceways, making the bearings unfit for further use.
Use a puller to withdraw the shaft, rotating the shaft during withdrawal to minimise the risk of damage. If no suitable puller is available, one can be made according to the illustration (➔ fig 6 ). The bar through the shaft is threaded at both ends. Turn the nut at the work side of the spindle to withdraw the shaft and bearings. While doing this, rotate the shaft to avoid damage to the bearings if the fit is tight. If there is no bore through the shaft, arrange a suitable attachment of the bar to the spindle nose.
Fig
5
1 7
Withdrawal of the shaft from housing: removal of the external cover
Removing the drive side bearing: inject the oil until the inner ring is released
Removal of the shaft using a puller Fig
4
Fig
6
6
SKF pump 729124 for pressure up to 100 MPa
82
83
1 Principles of bearing selection and application Removing drive side bearings If the drive side bearing has not already been removed by the oil injection method this should now be done. A puller to grip the side face of the spacer (6) is used. Do not pull over the roller set as this could make the puller lose its grip, damaging the bearing and making it unfit for further use. The required pulling force expressed in N is about 300 times the bore diameter expressed in mm. As the seating is tapered the pulling force acts only to release the bearing (➔ fig 7 ). The outer ring of the cylindrical roller bearing is still seated in the housing. Remove it using a puller, gripping the inner side-face of the ring. Do not put tools on the raceways if the bearings are to be used again. If you do not need to check the bearings, these may be left on site. Often the housing is provided with two diametrically opposed slots for gaining access with puller to the bearing inner side face (➔ fig 9 ).
Removing the locating device for the work side bearings The locating device for the work side bearings in this example is a so-called stepped sleeve. It is kept on the shaft by a rather heavy interference fit and ensures very good accuracy of the spindle. This method eliminates the need for threaded components and the inaccuracy that the threads can create. The stepped sleeve is fastened on the spindle by an interference fit that must be heavy enough to withstand the axial forces. The sleeve is mounted and dismounted by the oil injection method, thus ensuring careful handling of the components. The step that acts as a pressure surface during the mounting and dismounting operation can be sealed in two different ways; by the sleeve having two bore diameters, each with an interference fit on the shaft, or by using an O-ring. The latter system is somewhat easier from a manufacturing point of view.
Fig
8
1
SKF pump 728619 for pressure up to 150 MPa
Connecting nipples
Location device – stepped sleeve
8
Removal of the drive side bearing using a puller Fig
7
Fig
9
Removal of the outer ring of the cylindrical roller bearing
6
Removal of the locating device for the work side bearing
84
85
1 Principles of bearing selection and application Removal of the stepped sleeve requires a hydraulic pump. (➔ fig 8 page 85). The pump should have a capacity of at least 100 MPa. The same injector as that for releasing bearings on tapered seatings can be used. Connect the injector to the nipple that has been attached to the threaded hole of the sleeve. Put cloths around the shaft to dampen the sleeve when it comes loose. Be careful with all connections, as the oil pressure is high. Use only components that are certified for the pressure that can be delivered by the pump. A suitable oil for dismounting and mounting the sleeve is the SKF fluid LHDF 900. Start pumping and the sleeve will loosen when the pressure has reached a value of 60 – 100 MPa depending on size and actual fit. If the shaft or sleeve has been incorrectly manufactured, or if any of these components have been damaged, the sleeve may not come off completely. The oil will leak and there will be insufficient build up of pressure. If this is expected to happen the sleeve can be pushed off by hand while
the oil is injected. If it remains stuck, use a powerful puller. Look for any potential damage to the components to avoid problems in the future. Removal of work side bearings The work side bearings normally have a light interference fit on the shaft. The withdrawal force to be expected is 70 times the bore diameter for a set of three bearings, force in N and diameter in mm. The spindle used in the example is provided with three threaded holes in the spindle nose for dismounting purposes. By using these holes and three long screws the bearings can easily be removed from the shaft without any risk of damage. Use spacers between the screw ends and the sealing/spacer component (9) to avoid damaging the surface of this component. If the bearings have to be pushed a long distance, spacers with different lengths can be made to avoid screws being too long. If the spindle nose is not provided with dismounting holes, a long puller gripping the cover (10) or preferably the labyrinth/spacer (9) can be used (➔ fig 10 ).
Fig 10
Spindle with tandem set of angular contact ball bearings at both sides (➔ fig 11 ) A spindle having a tandem set of angular contact ball bearings at each side normally requires the drive side set to be withdrawn from the shaft at the same time as the shaft is withdrawn from the housing. The withdrawal force is then acting over the outer rings of this set and the shaft should be rotated during the withdrawal operation to minimise the risk of damage to the bearings.
Fig 11
Spacers
9
86
1
Spindle with tandem arrangement of angular contact ball bearings at both sides
Removal of the external cover using three long screws
Long screws
Dismounting spindles with other bearing arrangements
10
87
1 Principles of bearing selection and application Spindle with cylindrical roller bearing and angular contact thrust ball bearing at work side A cylindrical roller bearing at the work side of the spindle is dismounted in the same way as described for the drive side bearing. For removing this bearing, together with the angular contact thrust ball bearing generally present in this position, the system with screw should preferably be used if provided.
Otherwise a puller is used. It should grip over the inner ring of the cylindrical bearing or over the shaft sealing-washer. Depending on the design, access may be difficult and it might be necessary to pull over the housing cover and the outer rings. Angular contact thrust ball bearings normally have only a light fit and the withdrawal force is minimal (➔ fig 12 ).
Spindle with cylindrical roller bearing and angular contact thrust ball bearing at work side
Mounting Mounting a spindle with bearings arrangement 70 CD/TBT at the work side and NN 30 K at the drive side Before mounting the bearings, a grease of appropriate quality and quantity should be applied. For best performance of the spindle, a grease with synthetic base oil should be used. See section Grease lubrication under ‘Lubrication’ page 62 for details. The NN 30 K bearing at the drive side of the spindle should be adjusted to its final position by means of the spacer at the large end of the taper. This bearing should therefore be lubricated only when it is finally to be mounted. For bearings that will be used at relatively high speeds, it is recommended that the rust-inhibiting compound is washed away and the bearings are dried before applying
the grease. The properties of the grease are then better utilised. Special care must be taken to ensure that the bearings are not contaminated during washing. Using a syringe to apply the grease is a convenient way to get the proper quantity, and makes it easy for feeding inside the bearing. Distribute the grease evenly around the rolling element set. Mounting the work side bearings 1 Check that the distance between the housing seating abutment and housing cover side face LH, is smaller than the total width of the bearing package LB, measured over the outer rings. If not there will be an axial play in the spindle. It may be recommended to have LH 10 – 15 µm smaller for a diameter around 100 mm. Too large a difference may induce deformations when tightening the screws (➔ fig 13 ).
Mounting the work side bearings Fig 12
Fig 13
LB
LH
SKF pump 729124 for pressure up to 100 MPa
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1
1 Principles of bearing selection and application 2 Particularly when large bearings are used, the spindle should preferably be kept in a vertical position during the mounting procedure (➔ fig 14 ). 3 Position the shaft labyrinth (9); it may have to be warmed slightly, and the housing cover (10). Be sure not to forget the housing cover! 4 Warm the bearings on a hot plate or induction heater; 20 – 30 °C above ambient is normally sufficient to allow the bearings to pass freely over the shaft. 5 Ensure that the bearings are facing in the correct direction. If using a matched set look for the markings on the outside diameter of the outer rings.
6 Align the rings so that the marking for the “thickest” part is at the same position for the inner rings as for the outer rings. This will ensure the best possible division of load between the bearings. 7 Smear the bearing seatings lightly with a thin oil. 8 Position the bearings on to the shaft, not forgetting the two spacers (11) and (12) between the second and third bearing. The shaft spacer may have to be warmed.
Mounting the stepped sleeve (➔ fig 15 ) 1 Heat the stepped sleeve to about 150 °C above ambient for smaller sizes (bore diameter 60 mm) and about 110 °C for larger sizes, preferably with an induction heater. 2 When heated up, the sleeve can be easily handled by using the connecting nipple as a handle. Put the sleeve quickly on to the shaft so that the shaft does not heat up before the sleeve comes into contact with the bearings.
3 The sleeve should be allowed to cool down to room temperature before proceeding. 4 For final adjustment of the sleeve the oil injection method should be used. 5 Connect the nipples and the oil injector to the sleeve. 6 Provide for an arrangement that will apply an axial load over the sleeve-bearing system to withstand the force created by the oil injected to the sleeve, and to overcome the bearing fits and preload.
Mounting the stepped sleeve Fig 15
Mounting the work side bearings with the spindle in vertical position Fig 14
10 MPa
12 11
10
SKF pump 729124 for pressure up to 100 MPa
60–100 MPa
Do not forget to grease the bearings before mounting.
9
SKF pump 729124 for pressure up to 100 MPa
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1
1 Principles of bearing selection and application 7 Use a distance sleeve with length sufficient to cover the distance from the stepped sleeve to the position where the shaft is threaded – in this case the threads for the nut locating the drive side bearing. Use the nut to apply the necessary axial load or better still, use a hydraulic nut type SKF HMV E. A second oil pump must then be used. If the threads on the spindle do not match the threads of the hydraulic nut, a larger nut can be used and supported by the spindle nut. If there is no thread at all on the spindle, a support can be arranged, e.g. a washer that can be attached to the rear end of the spindle. 8 Tighten the nut or apply a pressure of about 30 MPa on the hydraulic nut. Inject oil to the stepped sleeve until it floats. There will probably be some leakage of oil. The required oil pressure is 60 – 100 MPa. While the sleeve is floating, tighten the nut or check that the required pressure for the hydraulic nut is still present. 9 The bearings must be protected from the pressure fluid as this can adversely
affect the lubrication properties of the grease. Wrap a clean lint-free cloth around the sleeve where it contacts the bearing to absorb any pressure fluid that may leak out. 10 Release the pressure for the stepped sleeve, wait until the oil has drained and then release the axial load. At this stage it is advisable to check the straightness of the spindle supported only by the work side bearings. Put the spindle on V-blocks as far apart as possible, and supporting the bearing outer rings. Rotate the shaft and measure the run-out at different positions of the shaft where it has suitable surfaces (➔ fig 16 ). If the values seem to be abnormal, a possible reason may be that the shaft has become misaligned due to spacers not having parallel side faces or shaft abutment/sleeve side face not being perpendicular to the bearing seating. Check by releasing the clamping load over the bearings.
Mounting the drive side bearings Drive side bearings with tapered bore should be adjusted to a suitable clearance or preload. The adjustment is made by pushing the inner ring up on the seating. The raceways will then expand. The final expansion determines the clearance or preload of the mounted bearing. The distance ring should have a width such that when the bearing is pushed up against the ring it will have the required clearance/preload (➔ fig 17 ).
A special gauge, an internal clearance gauge, of series GB 30 is available for accurate adjustment of the clearance/preload of bearings of series NN 30 K. This type of gauge is generally used by machine tool manufacturers and can usually be hired from SKF for occasional use (➔ fig 18 page 94). 1 The bearing outer ring need to be fitted in the housing. If the outer ring is to have a tight fit, the housing should be heated to between 10 and 30 °C above room temperature, e.g. in an oven or an oil
Mounting high-precision cylindrical roller bearings with GB 30 gauge Fig 17
Drive-up distance
Checking the shaft run-out Fig 16
SKF pump 729124 for pressure up to 100 MPa
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1
1 Principles of bearing selection and application bath. The heated housing with outer ring should then be allowed to cool down to ambient temperature. All components as well as the gauges must have the same stable temperature during the measuring procedure (➔ fig 19 ). 2 The bore gauge need to be introduced into the outer ring raceway, and the indicator set to zero. The raceway diameter measured in this way is transferred to the GB 30 gauge (➔ fig 20 ). 3 The bore gauge is applied to the centre of the gauging zone of the GB 30 gauge. The screw of the latter gauge is then adjusted until the indicator of the bore gauge shows zero minus a correction factor. The correction factor is given in
the instructions supplied with each GB 30 gauge (➔ fig 22 page 96). 4 The internal diameter of the envelope diameter gauge needs to be reduced by the value of the desired clearance, or increased by the value of the desired preload using the adjustment screw. The indicator on the envelope diameter gauge needs to be set to zero. The setting of the indicator should be left undisturbed from now on (➔ fig 25 page 97). 5 The tapered bearing seating on the spindle needs to be lightly oiled with thin oil. The inner ring with roller and cage assembly needs be lightly driven up on the tapered seating. The envelope diameter gauge needs to be expanded using the
adjustment screw and the gauge placed in position over the roller set. The adjustment screw needs then to be turned in the opposite direction until the gauge, by virtue of its inherent resilience, is in contact with the roller set. 6 The inner ring is driven further up on to its seating until the indicator on the gauge
again shows zero. The gauge needs to be expanded using the adjustment screw and removed. The required drive-up force in N is 200 – 400 times the bearing bore diameter in mm. 7 The distance between the mounted inner ring and the shoulder on the spindle needs to be measured using gauge blocks. Make
Pushing the inner ring up on the shaft until it firmly abuts the spacer ring Fig 21
Drive-up distance
Fig 18
Fig 19
Fig 20
SKF pump 729124 for pressure up to 100 MPa
94
95
1
1 Principles of bearing selection and application measurements at different positions for checking accuracy and misalignment. The difference should not normally be larger than 3 to 4 µm. The spacer ring needs then to be machined so that its width corresponds to this dimension (➔ fig 23 ). 8 The inner ring with roller and cage assembly needs to be withdrawn from the spindle. The finished spacer ring needs to be pushed up on to the spindle until it abuts the shoulder. The inner ring needs to then again be driven up until it firmly abuts the spacer ring. There should be no clearance between shoulder, spacer ring and inner ring (➔ fig 21 page 95). 9 The envelope diameter gauge needs to be applied to the roller set as described under point 5. The indicator must again show zero (➔ fig 24 ). 10 The bearing needs to be secured on the spindle. It is now time to apply the grease to the bearing. Put one string around each roller set and distribute it lightly over the rollers. Do not push any grease in between cage and inner ring shoulder. The spindle needs to be slowly turned as the inner ring and cage assembly are inserted in the outer ring to prevent the raceways and rollers from being damaged. For preloaded bearing arrangements, the housing with outer ring need to be heated as under point 1. If the cylindrical roller bearing is to be mounted together with an angular
Fig 23
contact thrust ball bearing, the cylindrical roller bearing outer ring needs to be withdrawn from the housing and pushed over the inner ring with cage and roller assembly before the spindle is inserted. The spindle with the complete bearings is then inserted in the heated bearing housing. The housing cover needs to be placed in position and the screws tightened.
Mounting cylindrical roller bearings without GB-type gauges A GB-type gauge is normally used by manufacturers making many of the same kind of spindles. For occasional needs it may not be necessary to invest in this equipment, but to use other methods to adjust for the proper clearance/preload. Some methods used in practice are described later on.
Measuring clearance of cylindrical roller bearings with outer ring Fig 25
Fig 22
B=L–
ec 1 000
Fig 24
γ=
96
Measuring clearance of cylindrical roller bearings with outer ring (➔ fig 25 ) Oil the bearing seating lightly with a thin oil and drive up the inner ring so that it gets a firm seat. There must still be a clearance between roller sets and outer ring. It can be assumed that the clearance is reduced by 8 µm for each 0,1 mm axial drive up of the inner ring. As small bearings may have a rather small clearance, for instance 15 µm,
360 e ∆ 1 000 s
97
1
1 Principles of bearing selection and application care must be taken not to push the inner ring too far up on the taper. The measuring principle is to use the outer ring of the bearing to measure the clearance at this initial position of the inner ring. The clearance is measured by moving the outer ring up and down. The total displacement is the clearance of the bearing at this
Example The clearance for bearing NN 3020 K was found to be 13 µm when the inner ring was driven up. The distance between bearing side face and abutment was 16,355 mm. The required preload is 3 µm. The inner diameter of the spindle is 51 mm and the outer diameter at the centre of the taper is 101,5 mm. The diameter ratio di/dm di/dm is then 0,5 making factor =16. The distance ring has to be adjusted to a width of B = 16,355 − 16 × 16/1 000 = 16,099 mm A tolerance of ± 0,005 mm is acceptable.
particular position of the inner ring. During this operation it is important that the outer ring is moved perpendicular to the shaft. The outer ring should not be subjected to large forces as it can elastically deform and an erroneous value will be obtained. To ensure that the outer ring is kept in the proper position when measuring,
Example The bearing outside diameter is 149,997 mm and the seating has a diameter of 149,992 mm. The raceway diameter will decrease by: 0,8 × (149,997 − 149,992) = 0,004 mm This value must be subtracted from c in the equation B = L − e c/1 000. If the interference fit is not taken into account the bearing preload may be too high. Considering the interference fit, the distance ring width would then be
its side face needs to be supported. This can be done by using a disc that is placed either in the space for the distance ring or is clamped between the drive-up device and the inner ring. In the former case the disc must be provided with a slot to allow access to the shaft for measuring the distance between the inner ring side-face and the abutment This distance is needed for determining the exact width of the distance ring. The distance is measured using gauge blocks as described earlier. When using the disc in this position it should not be too tightly clamped by the bearing inner ring as it must be rotated for measuring at different positions. When the distance has been accurately measured the bearing is removed and the spacer is adjusted to the width giving the required preload or clearance of the bearing. The width is calculated as follows: B = L − e c/1 000 For all details covering this equation, please see the high-precision cylindrical roller bearing/preloading bearing chapter page 189.
Other methods If the requirement is not as stringent as for very accurate preload adjustments, methods other than those described above may be used. Exact preload adjustment is not critical when the speeds are low but clearance needs to be avoided especially if the cylindrical roller bearing is mounted at the work side of the spindle. Using “feeling with the outer ring” The inner ring is driven up together with the outer ring. During drive-up the outer ring should be rotated back and forth and as preloading starts the ring will be harder to rotate. The degree of resistance to rotation that corresponds to the bearing having been driven up to a suitable preload can be learned by experience. When the proper position has been achieved the distance between the inner ring side-face and the abutment needs to be measured with gauge blocks. The width of the distance ring should be equal to this distance. With this method as with the method previously described, if the outer ring is to have an interference fit in the housing, compensation should be made for this.
B = 16,355 − 16 × (16 − 4)/1 000 = 16,163 mm
Compensation for interference fit If the outer ring is to have an interference fit in the housing seating the raceway diameter will decrease. It can be assumed that the raceway diameter will decrease by 80 % of the diametric interference fit.
If a threaded nut is used for driving up the inner ring assembly on the tapered seating, the angle through which the nut need to be turned for a given clearance reduction of the bearing can be calculated from the equation: γ = 360 e ∆/(1 000 s)
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1 Principles of bearing selection and application Inserting spindle shaft in the housing (➔ fig 26 ) The spindle with the work side bearings and the inner ring assembly of the drive side bearing can now be inserted in the housing. Heat the housing to 10 to 30 °C above ambient temperature to easily get the bearings into position. The spindle needs to be turned slowly as the inner ring and roller and cage assembly are inserted in the outer ring, to prevent the raceways and rollers from becoming damaged. Alternatively the spindle with only the work side bearings can be inserted, and after securing the housing cover, the inner ring assembly of the drive side bearing is driven up on the seating.
Mounting other bearings arrangements Spindle with tandem set of angular contact ball bearings at both sides (➔ fig 27 ) The drive side bearings for this spindle must be mounted after the shaft with the work side bearings has been inserted in the housing. This type of arrangement must have a clearance between drive side bearing outer rings and housing seating as the bearings should be axially displaceable. Therefore the bearings can be mounted without heating the housing. However it may be preferred to heat the bearings somewhat to get them on to the shaft more easily. The outer rings are then also expanded and to avoid forcing the bearings into the housing it should also be somewhat heated.
Spindle with tandem set of angular contact ball bearings at both sides
Inserting spindle shaft in the housing Fig 26
100
Mount the sealing components and the pulley and tighten the nut. Do not overtighten the screws for the housing covers – at the work side and at the drive side – as this may deform the housing seatings if the distance between the threads and the seatings is short.
Fig 27
Spindle with cylindrical roller bearing and angular contact thrust ball bearing at work side (➔ fig 28 ) A cylindrical roller bearing mounted together with an angular contact thrust ball bearing has to be inserted into the housing complete with the outer ring. The housing should then be heated to about 20 – 30 °C over ambient for easy introduction of the outer ring. The outside diameter of the angular contact thrust ball bearing has such tolerances that it will have a radial clearance in the housing even when the housing is not heated. The radial clearance between this bearing and the housing is necessary to ensure that only the cylindrical bearing is supporting the radial load.
Spindle with cylindrical roller bearing and angular contact thrust ball bearing at work side Fig 28
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1 Principles of bearing selection and application on opposite sides of the shaft centre line (➔ fig 32 page 104) the runout of the centre line at the position indicated by the gauge will be:
Fig 30
∆ Dm
1
∆ dm SKF
*
*
-3
∆ = a/L × (e1 + e2) + e1
∆ = a/L × (e1 − e2) + e1 The shaft wobble will be larger in the former case but it may give smaller runouts at positions between the bearings. However, it is easier to compensate for the runout in the latter case. If the raceway is concentric with the bore but is oval or has other types of macro form deviations, then the rotational centre will change during one revolution. The runout will be approximately the same as the form deviation. The non-repetitive runout must be considered for spindles with very exacting
A
5 67
When the eccentricities are on the same side of the shaft centre line (➔ fig 32 page 104) the runout will be:
7 0 1 0 C D/ P 4 A D B
gauging anvil applied to the ball along the spindle axis gives a reading corresponding to the axial runout of the spindle. If the raceway of the rotating inner ring is eccentric to the centre line of the shaft, then the shaft will have a runout that is twice the eccentricity (➔ fig 31 ). However in a truly circular raceway there will be a fixed rotational centre that is the centre of the raceway. In some applications the component that is to rotate can be centred to the true rotational centre and in such cases eccentricity errors may not be detrimental to the application. Grinding spindles are one example, where the grinding wheels can be dressed to concentricity with the axis of rotation. If the positions of the maximum eccentricity of the shaft and bearings are known, the bearing inner rings can be positioned in such a way that the eccentricities compensate each other. SKF angular contact ball bearings have marks indicating the largest eccentricity of both the inner and outer rings i.e. the thickest part of the rings, at position (3) in fig 30 . Having the eccentricities
-2
Checking running accuracy When the spindle has been assembled the running accuracy needs to be checked. With the methods most generally used for checking machine tool spindles, radial and axial runouts are measured on suitable surfaces at the spindle nose. It has been found however, that the ovality and eccentricity of the spindle surfaces from which measurements are taken are usually so great that it is difficult to obtain a true indication of the eccentricity of the axis of rotation of the spindle. A better method of measuring running accuracy (➔ fig 29 ) is to use an accurately ground sphere soldered to a plinth which is fitted to the spindle nose. The gauging anvil of a micro-indicator or some similar instrument of corresponding accuracy is applied to the ball. The plinth holding the ball is secured to the spindle nose in such a way that by lightly tapping the ball it can be moved at right angles to the spindle axis. The minimum reading obtained when the spindle is rotated indicates the radial accuracy of the unloaded spindle. An indicator with a flat
2
3
1
Markings on inner and outer rings for angular contact ball bearings: 1) designation; 2) serial number; 3) deviation from nominal diameter and position of the point of maximum eccentricity
Runout of shaft relative to inner raceway
Checking running accuracy of the spindle
Fig 31
Fig 29
Runout of shaft relative to inner ring raceway
Shaft
Eccentricity of inner ring
Inner ring raceway
102
103
1 Principles of bearing selection and application demands for accuracy, such as some types of grinding spindles and disk drive spindles. The non-repetitive runout cannot be compensated for by wheel dressing or by the control system of the machine, as may be the case for repetitive runout, and therefore very stringent demands are made on this type of runout, particularly fo disk drive spindles. Fig 33 illustrates the principle of non-repetitive runout in comparison with repetitive runout. The difference in diameters of the rolling elements will influence the non-repetitive runout. A certain repetitiveness may be noticed if one rolling element (or a few adjacent to each other) happens to have a larger diameter than the others. There will then be a runout with a repetitiveness equal to the cage rotational frequency. At certain times the maximum runout due to rolling elements, and the maximum runout due to
raceway will coincide and then give the total maximum runout of the bearing. If the cage speed is 40 % of the inner ring speed, a certain rolling element will coincide with a certain spot on the inner ring each fifth revolution. As the lubricant plays an important role in the non-repetitive runout, it is required to be very clean. Applications for which non-repetitive runout must be considered are usually grease lubricated, for instance workhead spindles for grinding machines and disk drive spindles. “Channelling” greases are often preferred, as once the grease has been overrolled and put aside, it stays more or less steady in its new position without disturbing the rolling elements at irregular intervals. A drawback with “channelling” grease can be that the oil bleeding is less efficient than with softer greases and this may influence the bearing life.
Inspection Cleaning of bearings SKF precision bearings are supplied in a preserved condition. Normally the preservative with which new bearings are coated before leaving the factory need not be removed from the bearings, just wiped off the outside surface and bore. If, however, the bearing is to be grease lubricated and used at very high or very low temperature, or when the grease (for example a polyurea grease) is not compatible with the preservative, it is necessary to wash and carefully dry the bearing. Care should also be taken not to introduce contaminants into the bearing.
Bearings contaminated because of improper handling (damaged packaging, etc.) should also be washed and dried before mounting. Washing of bearings being inspected during equipment servicing may also be necessary. When removal of preservative is necessary, it is possible to remove most of the preservative by blowing the bearing with clean dry air. Precautions must be taken when pressurised air is used to remove material from the bearings to prevent physical injury or chemical contamination of personnel in the area of such operations. When washing is necessary, the use of hydrocarbon solvents introduces several hazards (solvent flammability, health issues
Repetitive and non-repetitive runout Fig 33
Maximum spindle excursion from “true circle” in one revolution
Calculating the shaft runout
Repetitive radial runout
Fig 32
Non-repetitive radial runout “True circle” defined by nominal spindle radius 1
a
104
a
1
2 e1/2
L
2 e1/2
e2/2
b
a
e2/2
L
105
1
1 Principles of bearing selection and application etc.) to the work place, and these must be addressed before washing operations commence. When hydrocarbon washing is not possible, the use of aqueous solutions to clean bearings should only be considered when absolutely no other alternatives are possible. The washing solution should be maintained below 60 °C and the pH of the solution less than 12. The washing solution must be kept clean (see above) and preferably have a neutral pH that leaves either no residue or an oil-soluble residue on drying. If this is not available the washing fluid must be washed off the bearing, and the bearings completely dried as soon as possible. The bearings can be dried in hot dry air at temperatures up to 120 °C. It is also possible to use vacuum drying at lower temperatures. When this washing and drying procedure is completed the bearings must quickly be protected, usually by applying a coating of the lubricant to be used in the final operation. Both the phenolic resin and the polyamide cages used by SKF are capable of withstanding the conditions detailed above. If these washing conditions cannot be met (pH and temperature, especially when polymeric cages are employed), SKF strongly advises individual product testing to ensure the bearings are not affected by the procedure. Inspection of bearings If bearings have been disassembled from a spindle not because of a bearing damage, they may be fit for further use. Do not try to judge whether the bearings can be re-used until after they have been cleaned. Treat them as new. Never spin a dirty bearing. Instead, rotate it slowly while washing. Wash with a suitable solvent (white spirit, paraffin etc.). Dry with
106
a clean, lint-free cloth or with compressed, clean and moisture-free air, making sure that no bearing part starts rotating. Examine the bearings closely to determine whether they are re-usable. Use a small mirror and a dental-type probe with a rounded point to inspect raceways, cage and rolling elements. Be alert for scratches, marks, streaks, cracks, discolorations, mirror-like surfaces, contact patterns and so on. Spin the bearing gently and listen to the sound. An undamaged bearing can be remounted, but if it is not going to be used immediately after being cleaned, it needs to be oiled or greased to prevent corrosion. If the bearings are separable, do not mix the components of different individual bearings. Inspection of associated components Before mounting new bearings, the spindle, housing and other components adjacent to the bearings need to be checked. This is particularly important if the spindle performance has not been satisfactory, even though the bearings have been found to be in good condition.
The bearing seatings and other external surfaces are checked with the spindle mounted in V-blocks. Deviations are indicated by means of a dial gauge. The spindle is located axially at one end by using a ball fitted into a centre hole and supported against a bracket. When checking shaft shoulders, the spindle is pressed hard against the ball and the bracket while it is rotated, and measuring is done with an indicator as shown in the illustration (➔ fig 35 ). Tapered bearing seatings can be checked by using ring gauges of series GRA 30. The gauging or reference face is at the large end of the taper bore and is used
1
Fig 34
Checking the shaft radial and axial runout Fig 35
Inspection of shafts The dimensions of cylindrical bearing seatings can be easily checked with a snap gauge dial indicator as shown in the picture (➔ fig 34 ). Special measuring equipment is needed to check the form and position tolerances. A precision measuring instrument like Talyrond is the most suitable equipment for checking the roundness of spindle bearing seatings, but is not available in most workshops. The principle of checking radial and axial run-out of a shaft is shown in the fig 35 .
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1 Principles of bearing selection and application to determine the position of the tapered seating relative to a reference surface on the shaft. This reference surface may be either in front of, or behind the gauging face of the ring gauge. In addition to checking the position of the bearing seating and diameter, the ring gauge is used to check that the shaft shoulder is at right angles to the axis of the tapered seating by measuring the reference length R (➔ fig 36 ) at several diametrically opposed points. The form of the taper is checked by using marking blue. Applying just a very thin layer should give a marking coverage of at least 80 %. As an alternative to the ring gauge, a taper gauge can be used. The taper gauge covers a range of sizes and may be an economical solution when dealing with spindles of different sizes. Inspection of housings The dimensions and form of the housing seatings can be checked with a bore
indicator. To check the form, an attachment is fitted to the indicator to convert it into a three-point gauge. It is difficult to check the position of a shoulder relative to the housing seating in the absence of a reliable reference face. Quill housings of small spindles can usually be set up and rotated, thus making it possible to measure the axial run-out of the shoulder. This type of measurement does not necessarily prove that the shoulder is at right angles to the housing seating unless the housing seating axis coincides with the axis of rotation. Frequently there is no check made to ensure that both bearing seatings in a spindle housing have coinciding centre lines; the seatings are machined by the method giving the best results and that is all. If the centre lines do not coincide well the operating temperature may be too high, especially at high speeds. Checking the alignment may therefore be advisable. Measurements can be made by setting up the housing on a surface plate (➔ fig 38 )
so that the widest seating is parallel with the plate. The diameters of both seatings I and II are measured and the centre heights X1 and X2 and the difference ∆X = X1 − X2 are calculated. To check that bearing seating II is not misaligned relative to bearing seating I, dimension h is measured at two points; a and b between bearing seating II and the surface plate. The difference between the two read-off values should be less than or at the most equal to half any taper error of the bearing seating over the measuring distance m. m should be only a few millimetres less than the total width of the bearing seating. The housing is then rotated 90° on its axis and corresponding measurements are taken in the y direction. The eccentricity can then be calculated from the equation shown in fig 38 .
Inspection of spacers Spacers need to be checked for parallelity and flatness. For short spacers this can be done by measuring the width of the spacer at different positions while placed on a flat surface. Turning it upside down may indicate the flatness. Check if the two spacers between the bearings have the same width. This should normally be the case in order to achieve the right preload of the bearing set (➔ fig 37 ).
Inspection of housings Fig 38
I
II
e=
Measuring the reference length R
∏ ∆x + ∆y 2
2
Inspection of spacers Fig 36
Fig 37
∆x
b
a
R x2
x1
h
m
108
109
1
Angular contact ball bearings Contents
Angular contact ball bearings Four different designs Standard high-precision angular contact ball bearings High speed high-precision angular contact ball bearings Hybrid high-precision angular contact ball bearings Hybrid high speed high-precision angular contact ball bearings Universally matchable bearings Matched bearing sets General bearing data Factors affecting the preload Cages Speed ratings Equivalent dynamic bearing load Equivalent static bearing load Calculation of equivalent bearing load for preloaded angular contact ball bearings Designation systems of single bearings and matched sets Product tables Standard high-precision angular contact ball bearings High speed high-precision angular contact ball bearings Hybrid high-precision angular contact ball bearings Hybrid high speed high-precision angular contact ball bearings
2 112 112 114 114 115 115 116 117 122 127 135 136 137 137 139 139 141 142 156 162 172
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2 Angular contact ball bearings
Angular contact ball bearings Four different designs SKF high-precision angular contact ball bearings (➔ fig 1 ) are available in three dimension series: bearing series 719, 70 and 72 with a contact angle of 15° (designation suffix CD or CX and CE) or 25° (designation suffix ACD or ACX and ACE) (➔ fig 3 ). Bearings with the greater contact angle are recommended for applications where high axial stiffness and high axial load carrying capacity are required. The CX and ACX suffixes identify the small bearing sizes belonging to the CD and ACD design and stand for revised internal geometry.
Fig
2
2
719
70
72
A cross section of the three dimension series
Different designs of SKF high-precision angular contact ball bearings series 70
Single row high-precision angular contact ball bearing Fig
112
The CE and ACE design bearings have a larger number of small diameter balls compared with the standard CD or CX and ACD or ACX designs. Summing up, SKF high-precision angular contact ball bearings are available in four different designs and three dimension series (➔ fig 2 ). Clearly the space requirements are different and arrangements can be more or less radially compact. Each bearing series has characteristic features that makes it suitable for particular applications.
For higher speeds, or where little radial space is available, bearings of series 719 or 70 should be chosen. For heavy loads at relatively moderate speeds, bearings of series 72 are more appropriate. Where stiffness requirements are paramount, bearings of series 719 incorporate a large number of balls and have the advantage that large spindle diameters can be used. Both these factors contribute to high stiffness of the spindle system: spindle rigidity increases with increasing spindle diameter and bearing stiffness is more strongly influenced by the number than by the size of the balls. In fact, the rigidity of these light series bearings is greater than that, of comparable bearings from the heavier series.
1
Fig
25°
15°
ACD, ACX design
CD, CX design
25°
ACE design
3
15°
CE design
113
2 Angular contact ball bearings
Standard high-precision High-speed high-precision angular contact ball bearings angular contact ball bearings SKF standard high-precision angular contact ball bearings are non-separable, having one reduced height flange on the outer ring, in order to allow the introduction of a large number of balls, using a onepiece cage and an optimised internal design. Thanks to this, they represent the best solution in terms of load carrying capacity, rigidity and speed. The bearings are manufactured according to 719, 70 and 72 series, with a choice of two different contact angles: 15 degrees (CX and CD) or 25 degrees (ACX and ACD). The basic design is the same for CX (ACX) and CD (ACD) series. The CX and ACX series covering the small bearing sizes have recently been reviewed, offering improved dynamic and static load ratings, which have been increased by approx. 15 % and 30 % respectively. An enhanced level of radial and axial rigidity has also been obtained without compromising the speed ratings. The range of standard high-precision angular contact ball bearings covers bore diameters from 8 to 240 mm. Dimensions and technical data can be found in the relevant product tables.
114
In addition to the standard series, SKF offers a series of high-speed bearings to meet the highest demands in respect of speed capability and running accuracy. These bearings belong to the series 70 CE (ACE) and 719 CE (ACE) and are characterised by following features: ● smaller balls ● a contact angle of 15° (CE suffixes) or 25° (ACE suffix) ● both outer and inner ring shoulders of reduced height for better lubrication conditions ● an outer ring centred cage ● optimised internal design for enhanced speed capability ● an extremely high running accuracy. The CE and ACE design bearings have a larger number of small diameter balls compared with the standard CD, CX, ACD and ACX designs. Centrifugal forces from contact between the balls and the outer ring raceway are therefore further reduced, as is also the contact pressure. Because of the smaller balls of the CE and ACE designs, they occupy less of the bearing crosssection. The rings are therefore correspondingly thicker. This means that any form errors of shaft or housing bore have less influence on the roundness of the bearing rings. As a result the running accuracy is enhanced. The range of very high-speed bearings covers bore diameters from 20 to 120 mm. Technical data and dimensions can be found in the tables. Details concerning technical data and availability of other sizes will be supplied on request.
Hybrid high-precision Hybrid high-speed angular contact ball bearings high-precision angular contact ball bearings If the performance required is close to the limits for all-steel bearings, or if higher rigidity or longer life are needed, an alternative may be to select SKF hybrid bearings. These bearings have steel rings and ceramic balls. The advantages offered by ceramic material versus steel are shown in chapter 1: “Principles of bearing selection and application”, section “material for highprecision bearings”. Hybrid high-precision angular contact ball bearings offer the following advantages versus all-steel bearings: ● lasting up to four to six times longer ● achieving up to 20 % higher speed ● lower temperature rise in the system ● obtaining higher rigidity ● fewer problems with lubrication and vibration. ● less sensible to speed accelerations and decelerations.
These bearings have smaller ceramic balls, inner and outer ring shoulders of reduced height, outer ring centred cage, optimised internal design, and are suitable for even more demanding applications than those covered by hybrid precision angular contact ball bearings. With proper lubrication conditions and with moderate loading rotational speeds can go up to 3 million n × dm. By using specially designed hybrid bearings, the spindle speed can be further increased. The SKF range comprises two series of hybrid high-speed high-precision angular contact ball bearings of series 719 (CE and ACE) and 70 (CE and ACE). The bearings are identified by the suffix HC in the designations, e.g. 7014 CEGA/HCP4A.
Hybrid high-precision angular contact ball bearings are offered in the same execution as all-steel high-precision angular contact ball bearings, series 719, 70 and 72 with either 15 (CD and CX) or 25 (ACD and ACX) degrees contact angle. Hybrid highprecision angular contact ball bearings are identified by the suffix HC in the designation, e.g. 7014 CDGA/HCP4A.
115
2
2 Angular contact ball bearings
Universally matchable bearings Universally matchable angular contact ball bearings are adjusted during manufacture so that they may be mounted immediately adjacent to each other in a back-to-back, face-to-face or tandem arrangement, as desired. When arranged back-to-back or face-to-face the bearings will have a light, medium or heavy preload depending on the requirements. Basic features such as accuracy, preload class, speed capability etc. of universally matchable angular contact ball bearings are the same as those of the pre-matched sets. Universally matchable bearings may be useful in reducing stock holding and improving availability. Several specific matched sets may be obtained by stocking the correct universal bearings.
Universal bearings can be supplied in two basic executions: single universal bearings for mounting in any combination, or duplex sets with matched bore and outside diameters. The designations for single universal bearings are explained in Table 1 . Customers need to order the same number of single universal bearings as the number of bearings in a set, e.g. to replace a set 7014 CD/P4ATBTA, three bearings 7014 CDGA/P4A are required. Alternatively, duplex sets of universally matchable bearings can be chosen. Duplex universal bearings can either be used as sets, or each bearing used to form other groups of bearings, with the only limitation being the contact angle and the preload class. Universal bearings with light preload must not be paired against bearings with a different contact angle or preload class. For such special cases, please consult the SKF application engineering service.
Designation of single universal high-precision angular contact ball bearings Table
70 10 CD G A / P4A
1
Table 2 shows some possible combinations and the corresponding number of matched sets, single bearings or duplex sets to be ordered. Marking of universally matchable bearings The bearing rings have several markings for identification purposes. Each bearing is marked with the complete designation on the outer ring face. To facilitate the selection of the actual bore and outside diameters in order to obtain the desired fits after mounting, the actual deviation of the inner bore diameter and outside diameter from nominal, are marked on the inner ring/outer ring respectively. An asterisk marks the position of the greatest out-of-round on the inner and outer ring side-faces. This is where the greatest wall thickness between the base of the raceway and the bore or the outside diameter surface can be found. A “chevron V” is marked on the outer ring outside diameter indicating the contact angle direction. This allows the users to check that universally matchable bearings, once fitted on the shaft, are correctly positioned according to the desired combination, i.e. back-to-back, face-to-face, etc. (➔ fig 8 page 121).
Matched bearing sets SKF high-precision angular contact ball bearings are also supplied as complete sets of two, three or four bearings. They are matched during manufacturing so that when the bearings are mounted immediately next to each other, the predetermined value of the preload will be obtained, or the load will be evenly distributed. The bore and outside diameters do not differ by more than one third of the permissible diameter tolerance. There is even less difference between the diameters of matched bearings manufactured to tolerance class PA9A. The most popular set arrangements are shown in figs 4 , 5 , 6 and 7 pages 118 – 119. The load lines of bearings arranged backto-back diverge towards the bearing axis. Axial load can be accommodated in both directions, although only by one bearing (or bearings in tandem) at a time. The back-toback arrangement is relatively stiff and can also take up tilting moments.
Tolerance class P4A or PA9A Preload class A: light, B: medium, C: heavy Table
Universally matchable execution Contact angle and internal design CD, CE, CX = 15 degrees ACD, ACE, ACX = 25 degrees
Original matched set
Qty
Single universal bearing
Qty
Duplex universal bearing sets
Qty
Bore diameter
7010 CD/P4ATBTA
2
7010 CDGA/P4A
6
7010 CD/P4ADGA
3
Bearing series
7010 CD/P4AQBCA
2
7010 CDGA/P4A
8
7010 CD/P4ADGA
4
7010 CD/P4ADT
5
7010 CDGA/P4A
10
7010 CD/P4ADGA
5
7010 CD/P4ADBA
15
7010 CDGA/P4A
30
7010 CD/P4ADGA
15
7010 CD/P4ADFA
4
7010 CDGA/P4A
8
7010 CD/P4ADGA
4
2
See Table 17 for more details
116
117
2
2 Angular contact ball bearings The load lines of bearings arranged faceto-face converge towards the bearing axis. Axial loads can be accommodated in both directions, although again only by one bearing (or bearings in tandem) at a time. The arrangement is not so stiff as the back-to-back arrangement and is less suitable for tilting moments. In a tandem arrangement the load lines of the bearings are parallel. Radial and axial loads are equally distributed over the bearings but axial loads can only be carried in one direction. A set of bearings in tandem is therefore generally adjusted against another bearing that can take the axial loads acting in the opposite direction. Combinations of tandem and back-toback, or tandem and face-to-face are normally used when the design makes it impossible to adjust a further bearing, or bearing set against the tandem set.
Fig
4
118
7
2 Combination of tandem and back-to-back arrangement Designation suffix TBT
Combination of tandem and face-to-face arrangement Designation suffix TFT
Back-to-back arrangement for axial load in both directions
Back-to-back arrangement Designation suffix DB
Fig
Fig
Fig
5
Face-to-face arrangement for axial load in both directions
Tandem arrangement for axial load in one direction
Face-to-face arrangement Designation suffix DF
Tandem arrangement Designation suffix DT
Combination of tandem and back-to-back arrangement Designation suffix QBC
Combination of tandem and face-to-face arrangement Designation suffix QFC
Combination of tandem and back-to-back arrangement Designation suffix QBT
Combination of tandem and face-to-face arrangement Designation suffix QFT
6
Tandem arrangement Designation suffix TT
Tandem arrangement Designation suffix QT
119
2 Angular contact ball bearings Marking of bearing sets Bearing sets not only have the markings of single bearings; but also have additional markings for identification purposes and to indicate how the bearings of a matched set should be correctly mounted. A ‘V’-shaped marking is to be found on the outside diameter of the bearings. The bearings need to be mounted in the order shown by this marking to obtain the correct preload. It also indicates how the set should be mounted compared with the axial load. The point of the ‘V’ gives the direction in which the axial load should act on the inner ring(s). Where axial loads act in both directions, the ‘V’ point gives the direction of the greater axial load.
Fig
Each bearing of a matched set is marked with the complete designation of the bearing set. The same serial number is shown on the face of the outer ring (➔ figs 9 and 10 ).
8
Fig
9
2
“V” – shaped marking on outside diameter of universally matchable bearings for paired mounting Example of a set of three universally matchable bearings combined in TBT arrangement
“V” – shaped marking on outside diameter of high precision angular contact ball bearing sets
Marking of bearing sets Fig 10 Serial number (for sets only): 916
Bore diameter deviation from nominal: –5; and position of the point of maximun eccentricity of the inner ring:
*
Manufacturing date: W41Y
Complete bearing designation: 71916 ACE/HCP4ADBA Chevron V
Outside diameter deviation from nominal: –4; and position of the point of maximun eccentricity of the outer ring:
*
120
Country of origin: Italy V
121
2 Angular contact ball bearings
General bearing data
Tolerances SKF high-precision angular contact ball bearings are manufactured to tolerance class P4A specifications as standard. On request, bearings can be made according to class PA9A or other specifications. The values for P4A and PA9A tolerance classes are given in Tables 3 and 4 . Hybrid bearings are made to the same tolerances as the corresponding all-steel bearings.
Dimensions SKF high-precision angular contact ball bearings conform to ISO 15:1998, Diameter Series 9, 0 and 2.
Class P4A tolerances for radial bearings
Class PA9A tolerances for radial bearings Table
Inner ring d over
incl.
mm
Hybrid high-precision angular contact ball bearings (identified by the suffix HC) are normally supplied either with preload class A or B since the heavy preload is not recommended for high-speed operations. For the same reason preload classes A and B are usually applied to the high-speed high-precision angular contact ball bearings (identified by suffixes CE and ACE), fitted either with steel or ceramic balls. Tables 5 page 124, 6 page 125 and 7 page 126 show preload values for bearing pairs arranged either back-to-back or faceto-face prior to mounting.
Preload To meet varying customer needs in terms of speed, heat generation and rigidity, SKF offers standard high-precision angular contact ball bearings (identified by suffixes CX, CD, ACX and ACD), universally matchable and matched back-to-back or face-to-face in groups of two or more bearings per set, with three different preload classes as standard: Class A: light preload Class B: medium preload Class C: heavy preload
3
Table Inner ring
∆dmp high
low
µm
∆ds high
low
µm
Vdp max
Vdmp max
∆Bs high
µm
µm
µm
low
∆B1s high
low
µm
VBs max
Kia max
Sd max
Sia max
d over
µm
µm
µm
µm
mm
incl.
∆ds high
low
µm
Vdp max
Vdmp max
∆Bs high
µm
µm
µm
low
∆B1s high
low
µm
VBs max
Kia max
Sd max
Sia max
µm
µm
µm
µm
2,5 10 18
10 18 30
0 0 0
–4 –4 –5
0 0 0
–4 –4 –5
1,3 1,3 1,3
1 1 1
0 0 0
–40 –80 –120
0 0 0
–250 –250 –250
1,3 1,3 1,3
1,3 1,3 2,5
1,3 1,3 1,3
1,3 1,3 2,5
2,5 10 18
10 18 30
0 0 0
–2,5 –2,5 –2,5
1,3 1,3 1,3
1 1 1
0 0 0
–25 –80 –120
0 0 0
–250 –250 –250
1,3 1,3 1,3
1,3 1,3 2,5
1,3 1,3 1,3
1,3 1,3 2,5
30 50 80
50 80 120
0 0 0
–6 –7 –8
0 0 0
–6 –7 –8
1,3 2 2,5
1 1,3 1,5
0 0 0
–120 –150 –200
0 0 0
–250 –250 –250
1,3 1,3 2,5
2,5 2,5 2,5
1,3 1,3 2,5
2,5 2,5 2,5
30 50 80
50 80 120
0 0 0
–2,5 –3,8 –5
1,3 2 2,5
1 1,3 1,5
0 0 0
–120 –150 –200
0 0 0
–250 –250 –380
1,3 1,3 2,5
2,5 2,5 2,5
1,3 1,3 2,5
2,5 2,5 2,5
120 150 180
150 180 250
0 0 0
–10 –10 –12
0 0 0
–10 –10 –12
6 6 7
3 3 4
0 0 0
–250 –250 –300
0 0 0
–380 –380 –500
4 4 5
4 6 7
4 5 6
4 6 7
120 150 180
150 180 250
0 0 0
–6,5 –6,5 –7,5
3 3 4
2 2 2,5
0 0 0
–250 –300 –350
0 0 0
–380 –500 –500
2,5 3,8 3,8
2,5 5 5
2,5 3,8 3,8
2,5 5 5
∆Ds high
VDp max
VDmp max
∆Cs, ∆C1s
low
VCs max
Kea max
SD max
Sea max
µm
µm
µm
µm
µm
µm
µm
Values are identical to those for inner ring of same bearing (∆Bs, ∆B1s)
1,3 1,3 1,3
2,5 2,5 3,8
1,3 1,3 1,3
2,5 2,5 3,8
2,5 2,5 2,5
5 5 5
2,5 2,5 2,5
5 5 5
3,8 3,8 6,5
6,5 6,5 7,5
3,8 3,8 6,5
6,5 6,5 7,5
Outer ring D over
incl.
mm
Outer ring ∆Dmp high
low
µm
∆Ds high
low
µm
VDp max
VDmp max
µm
µm
18 30 50
30 50 80
0 0 0
–5 –6 –7
0 0 0
–5 –6 –7
2 2 2
1,3 1,3 1,3
80 120 150
120 150 180
0 0 0
–8 –9 –10
0 0 0
–8 –9 –10
2,5 2,5 6
1,3 1,5 3
180 250 315
250 315 400
0 0 0
–11 –13 –15
0 0 0
–11 –13 –15
6 8 9
4 5 6
122
4
∆Cs, ∆C1s
Values are identical to those for inner ring of same bearing
VCs max
Kea max
SD max
Sea max
D over
µm
µm
µm
µm
mm
1,3 1,3 1,3
2,5 2,5 3,8
1,3 1,3 1,3
2,5 2,5 3,8
18 30 50
30 50 80
0 0 0
–3,8 –3,8 –3,8
2 2 2
1,3 1,3 1,3
2,5 2,5 4
5 5 6
2,5 2,5 4
5 5 6
80 120 150
120 150 180
0 0 0
–5 –5 –6,5
2,5 2,5 3
1,3 1,5 2
5 5 7
8 9 10
5 6 8
8 8 10
180 250 315
250 315 400
0 0 0
–7,5 –7,5 –10
4 4 5
2,5 3,5 5
incl.
µm
123
2
2 Angular contact ball bearings Table Bearing
Bore diameter
Size
mm
Axial preload Series 719 ACD 719 ACD/HC 719 ACX and 719 ACX/HC Class A B C1)
5
Table Bearing
Series 719 CD 719 CD/HC 719 CX and 719 CX/HC Class A B C1)
Series 719 ACE and 719 ACE/HC
Series 719 CE and 719 CE/HC
Class A
Class A
B
B
N
Bore diameter
Size
mm
Axial preload Series 70 ACD 70 ACD/HC 70 ACX and 70 ACX/HC Class A B C1)
Series 70 CD 70 CD/HC 70 CX and 70 CX/HC Class A B C1)
Series 70 ACE and 70 ACE/HC
Series 70 CE and 70 CE/HC
A
B
A
B
00 01 02 03 04 05
15 15 25 25 35 40
30 30 50 50 70 80
60 60 100 100 140 160
10 10 15 15 25 25
20 20 30 30 50 50
40 40 60 60 100 100
– – – – 35 40
– – – – 105 120
– – – – 20 25
– – – – 60 75
8 9 10 12 15 17
8 9 00 01 02 03
20 20 25 25 30 40
40 40 50 50 60 80
80 80 100 100 120 160
10 10 15 15 20 25
20 20 30 30 40 50
40 40 60 60 80 100
– – – – – –
– – – – – –
– – – – – –
– – – – – –
30 35 40 45 50 55
06 07 08 09 10 11
40 60 70 80 80 120
80 120 140 160 160 240
160 240 280 320 320 480
25 35 45 50 50 70
50 70 90 100 100 140
100 140 180 200 200 280
40 55 75 80 80 120
120 165 225 240 240 360
25 35 45 50 50 75
75 105 135 150 150 225
20 25 30 35 40 45
04 05 06 07 08 09
50 60 90 90 100 170
100 120 180 180 200 340
200 240 360 360 400 680
35 35 50 60 60 110
70 70 100 120 120 220
140 140 200 240 240 440
55 55 80 80 90 105
165 165 240 240 270 315
35 35 50 50 55 65
105 105 150 150 165 195
60 65 70 75 80 85
12 13 14 15 16 17
120 120 200 210 220 270
240 240 400 420 440 540
480 480 800 840 880 1 080
70 80 130 130 140 170
140 160 260 260 280 340
280 320 520 520 560 680
120 130 170 180 180 230
360 390 510 540 540 690
75 80 105 110 110 140
225 240 315 330 330 420
50 55 60 65 70 75
10 11 12 13 14 15
180 230 240 240 300 310
360 460 480 480 600 620
720 920 960 960 1 200 1 240
110 150 150 160 200 200
220 300 300 320 400 400
440 600 600 640 800 800
115 120 130 130 180 180
345 360 390 390 540 540
70 75 80 80 110 110
210 225 240 240 330 330
90 95 100 105 110 120
18 19 20 21 22 24
280 290 360 360 370 450
560 580 720 720 740 900
1 120 1 160 1 440 1 440 1 480 1 800
180 190 230 230 230 290
360 380 460 460 460 580
720 760 920 920 920 1 160
230 245 295 300 310 385
690 735 885 900 930 1 155
140 150 180 185 190 235
420 450 540 555 570 705
80 85 90 95 100 105
16 17 18 19 20 21
390 400 460 480 500 560
780 800 920 960 1 000 1 180
1 560 1 600 1 840 1 920 2 000 2 360
240 250 300 310 310 360
480 500 600 620 620 720
960 1 000 1 200 1 240 1 240 1 440
230 230 295 295 300 –
690 690 885 885 900 –
140 140 180 180 185 –
420 420 540 540 555 –
130 140 150 160
26 28 30 32
540 560 740 800
1 080 1 120 1 480 1 600
2 160 2 240 960 3 200
350 360 470 490
700 720 940 980
1 400 1 440 1 880 1 960
– – – –
– – – –
– – – –
– – – –
170 180 190 200 220
34 36 38 40 44
800 1 000 1 000 1 250 1 300
1 600 2 000 2 000 2 500 2 600
3 200 4 000 4 000 5 000 5 200
500 630 640 800 850
1 000 1 260 1 280 1 600 1 700
2 000 2 520 2 560 3 200 3 400
– – – – –
– – – – –
– – – – –
– – – – –
110 120 130 140 150 160
22 24 26 28 30 32
650 690 900 900 1 000 1 150
1 300 1 380 1 800 1 800 2 000 2 300
2 600 2 760 3 600 3 600 4 000 4 600
420 430 560 570 650 730
840 860 1 120 1 140 1 300 1 460
1 680 1 720 2 240 2 280 2 600 2 920
– – – – – –
– – – – – –
– – – – – –
– – – – – –
170 180 190 200 220 240
34 36 38 40 44 48
1 250 1 450 1 450 1 750 2 000 2 050
2 500 2 900 2 900 3 500 4 000 4 100
5 000 5 800 5 800 7 000 8 000 8 200
800 900 950 1 100 1 250 1 300
1 600 1 800 1 900 2 200 2 500 2 600
3 200 3 600 3 800 4 400 5 000 5 200
– – – – – –
– – – – – –
– – – – – –
– – – – – –
All-steel bearings only
2
N
10 12 15 17 20 25
1)
6
Series 719 Preload in bearings for universal pairing and bearing sets arranged back-to-back or face-to-face
Series 70 ➤ Preload in bearings for universal pairing and bearing sets arranged back-to-back or face-to-face
124
1)
All-steel bearings only
125
2 Angular contact ball bearings
Factors affecting the preload
To calculate preload for sets of bearings involving more than four bearings, or for sets incorporating bearings of different designs, size and contact angle, please contact SKF application engineering service.
Sets of three or more bearings have a higher preload than sets of two bearings. The relevant preload value can be calculated by multiplying the preload values of pairs reported in the tables by the following factors: 1,35 for TBT and TFT sets 1,60 for QBT and QFT sets 2,00 for QBC and QFC sets.
Preload on bearing systems is influenced by several factors under static and dynamic conditions. The actual preload value on the bearings fitted in a system differs from the predetermined preload value in the manufacturing process, depending on: ● the actual fits between the bearing inner rings and the shaft, and between the bearing outer rings and the housing ● the system speed for constant position arrangements.
Series 72 Preload in bearings for universal pairing and bearing sets arranged back-to-back or face-to-face Table Bearing
Axial preload Series 72 ACD 72 ACD/HC 72 ACX and 72 ACX/HC Class A B C1)
Series 72 CD 72 CD/HC 72 CX and 72 CX/HC Class A B
C1)
Bore diameter
Size
mm
–
N
10 12 15 17 20 25
00 01 02 03 04 05
35 35 45 60 70 80
70 70 90 120 140 160
140 140 180 240 280 320
20 20 30 35 45 50
40 40 60 70 90 100
80 80 120 140 180 200
30 35 40 45 50 55
06 07 08 09 10 11
150 190 240 260 260 330
300 380 480 520 520 660
600 760 960 1 040 1 040 1 320
90 120 150 160 170 210
180 240 300 320 340 420
360 480 600 640 680 840
60 65 70 75 80 85
12 13 14 15 16 17
400 450 480 500 580 600
800 900 960 1 000 1 160 1 200
1 600 1 800 1 920 2 000 2 320 2 400
250 290 300 310 370 370
500 580 600 620 740 740
1 000 1 160 1 200 1 240 1 480 1 480
90 95 100 105 110 120
18 19 20 21 22 24
750 850 950 1 000 1 050 1 200
1 500 1 700 1 900 2 000 2 100 2 400
3 000 3 400 3 800 4 000 4 200 4 800
480 520 590 650 670 750
960 1 040 1 180 1 300 1 340 1 500
1 920 2 080 2 360 2 600 2 680 3 000
1)
7
Other effects may influence the actual preload of angular contact ball bearings systems while operating such as: ● temperature differences in operation between the bearing inner ring and outer rings and the rolling elements ● the shaft and housing materials (i.e. different materials may show varying thermal expansion coefficients, resulting in a differential deformation of the mating part while the system is operating). ● geometric errors (e.g. imposed misalignment, cylindricity and conicity errors, coaxiality errors between front and rear housing). In case of applications where the above points may be important please contact the SKF application engineering service for advice.
Influence of the fit on the preload When a bearing is mounted with an interference fit on the shaft, the inner ring will expand, increasing the raceway diameter. Conversely, an interference fit in the housing will compress the outer ring, reducing the raceway diameter. One of these conditions alone or both together, will reduce the space for the rolling elements and thus increase the preload of the bearing set. The preload change thus depends on the real fit between bearings and mating parts. When mating parts are made to tolerances according to the recommendations given in Tables 1 and 2 pages 42 – 43 (e.g. js4 for shafts and JS5 for housings for bearings of P4A precision class) the preload increase can then be calculated from the following equation with reasonable accuracy. Gm = f f1 f2 fHC GA, B, C where Gm = preload of the mounted bearing sets, N GA, B, C = preload of bearing sets prior to mounting, see Tables 5 , 6 and 7 pages 124 – 126 f = bearing factor, see Diagram 1 page 129 f1 = correction factor depending on contact angle, see Table 8 page 128 f2 = correction factor depending on preload class, see Table 8 fHC = correction factor for hybrid bearings where applicable, see Table 8
All-steel bearings only
126
127
2
2 Angular contact ball bearings
Example What will be the preload of the bearing pair 71924 CD/P4ADBC when mounted? From Table 5 page 124, the value of GC is 1 160 N. The value of the bearing factor f = 2,2 according to Diagram 1 . The correction factors obtained from Table 8 are f1 = 1 and f2 = 1,24. Therefore, Gm = f f1 f2 GC Gm = 2,2 × 1 × 1,24 × 1 160 N = 3 165 N
Influence of speed on preload A drastic increase in preload may also occur when approaching very high-speeds. The increase is mostly due to the centrifugal load affecting the position of the rolling elements. Thus, adoption of ceramic balls allows much higher rotational speeds, while maintaining low heat generation and
In other cases the fits may have to be significantly higher, for instance in very high-speed spindles, to avoid the bearing inner ring from loosening its contact with the shaft as a result of the centrifugal force. The effect of fits must then be calculated in more detail. For special cases such as these, please consult the SKF application engineering service. The relationship between bearing fits, shafts, housing proportions and preload increases can be studied according to Diagram 1 .
2
Bearing factor f Diagram
1
Bearing factor f 2,4
List of correction factors for preload calculation Table Bearing series
fHC1)
719 CD and CX 719 ACD and ACX 719 CE 719 ACE 719 CD/HC and CX/HC 719 ACD/HC and ACX/HC 719 CE/HC 719 ACE/HC
1 1 1 1 1,08 1,08 1,06 1,05
70 CD and CX 70 ACD and ACX 70 CE 70 ACE 70 CD/HC and CX/HC 70 ACD/HC and ACX/HC 70 CE/HC 70 ACE/HC 72 CD and CX 72 ACD and ACX 72 CD/HC and CX/HC 72 ACD/HC and ACX/HC
f12)
f23) Preload A
f23) Preload B
f23) Preload C
1 0,92 1 0,92 1 0,92 1 0,92
1 1 1 1 1 1 1 1
1,12 1,1 1,14 1,14 1,12 1,12 1,14 1,14
1,24 1,21 – – – – – –
1 1 1 1 1,07 1,06 1,02 1,03
1 0,92 1 0,96 1 0,92 1 0,96
1 1 1 1 1 1 1 1
1,1 1,09 1,08 1,08 1,1 1,09 1,09 1,07
1,2 1,18 – – – – – –
1 1 1,04 1,02
1 0,95 1 0,95
1 1 1 1
1,04 1,05 1,04 1,04
1,1 1,1 – –
8
2,2
2
1,8
1,6
1,4
1) 2) 3)
1,2
1 0 70 CD, ACD CX and ACX
20
40 70 CE
60
80
100
719 CD, ACD CX and ACX
120 719 CE
140
160
180
72 CD, ACD CX and ACX
200
220
240
260
280
Bore diameter, mm
fHC = correction factor for ceramic balls f1 = correction factor for contact angle f2 = correction factor dependent on preload
128
129
2 Angular contact ball bearings adequate stiffness. In Diagram 2 the preload variation versus speed for different executions of basic bearing type 7014 is shown. For applications where speed is in excess of 1 – 1,2 million n dm and constant position preload is necessary, please consult the SKF Application Engineering Service for more details. For high-speed applications like internal grinding spindles and high-frequency milling
spindles, the preload is often given through a set of elastic calibrated springs (➔ fig 11 ), or alternatively hydraulic preload is used. Table 9 gives guideline values for the spring force to be applied on bearings in constant load arrangements. The values refer to single bearings with 15 degrees contact angle (suffixes CX, CD and CE), both all-steel and hybrid, of the most popular sizes used with spring preload
Fig 11
systems. If bearings are paired in tandem, the value in the table needs to be multiplied by the number of single bearings in the set. The above values are calculated to minimise the difference in contact angle between outer and inner raceway contacts, and to retain a certain axial rigidity of the bearing at high speed. However, it should be noted that additional preload is detrimental to performance because of heat generation.
2
Preload increase factor for different bearing designs Reference base type 7014 Diagram
For applications where extremely high speed is required preloading should be done through calibrated springs acting against a bearing ring
2
Preload increase factor 8 15°
CD (all-steel)
7
6
Table Bearing size
15°
CE (all-steel) 5
Speed factor (n dm × 106) 2,25 2,0 Preload
1,75
1,5
1,25
9
Guideline values for the spring force in constant load bearing arrangements
N 15°
4
CD/HC (hybrid)
Constant load 3
15°
CE/HC (hybrid)
2
1
7000 7001 7002 7003 7004 7005
150 150 160 175 250 280
150 150 160 175 250 280
150 150 160 150 200 250
125 125 125 125 150 200
100 100 100 100 150 175
7006 7007 7008 7009 7010 7011 7012
350 400 400 750 750 1 000 1 000
350 400 400 750 750 1 000 1 000
300 350 350 650 650 900 900
200 300 300 500 500 800 800
175 200 200 400 400 600 600
0 0
0,45
0,9
1,35
1,8
Speed factor, n dm (× 106)
130
131
2 Angular contact ball bearings Preload for customised needs Most often, intermediate rings (spacers) are inserted between the bearings of a set (➔ fig 12 page 135). When a special preload may be required to achieve the best performance, it is possible to change preload by face grinding the inner or outer spacer. It is not advisable to modify the bearings in any way.
Tables 10 and 11 show which spacer(s) should be ground to increase or decrease the preload. Tables 12 and 13 , page 134 show the necessary width reduction to be achieved by face grinding. Spacers are not only used to customise the preload but to improve the system rigidity, and sometimes to bring the oil pipes as close as possible to the raceways. In
Table 12 Bearing size
Table 10 Bearing arrangement
The part to be face ground
Amount to be ground off to increase preload from A up to B B up to C
A up to C
Back-to-back
Inner spacer
a
b
a+b
Face-to-face
Outer spacer
a
b
a+b
Table 11 Bearing arrangement
The part to be face ground
Amount to be ground off to decrease preload from B down to A C down to B
C down to A
Back-to-back
Outer spacer
a
b
a+b
Face-to-face
Inner spacer
a
b
a+b
132
Spacer(s) to be ground to increase preload
Spacer(s) to be ground to decrease preload
2
Spacer width reduction for changing preloads in matched sets, CD, CX and CE designs
Spacer adjustment Series 719 CD Series 70 CD 719 CD/HC 70 CD/HC 719 CX 70 CX and 719 CX/HC and 70 CX/HC
Series 72 CD 72 CD/HC 72 CX and 72 CX/HC
Series 719 CE and 719 CE/HC
Series 70 CE and 70 CE/HC
a
Bore diameter
Size
mm
–
µm
8 9 10 12 15 17
8 9 00 01 02 03
20 25 30 35 40 45
b
a
b
a
b
a
a
– – 4 4 5 5
– – 6 6 7 7
4 4 5 5 5 6
6 6 7 7 8 9
– – 6 6 7 8
– – 9 9 11 11
– – – – – –
– – – – – –
04 05 06 07 08 09
5 5 5 6 7 7
8 8 8 10 11 11
7 7 8 8 8 12
10 10 13 13 13 17
8 8 11 12 13 14
12 12 15 17 21 21
10 11 11 13 14 15
14 13 16 15 15 16
50 55 60 65 70 75
10 11 12 13 14 15
7 10 10 10 13 13
12 15 15 18 19 19
12 14 14 14 15 15
17 19 19 20 23 23
14 16 18 20 20 20
21 24 26 29 29 29
15 21 21 22 25 25
17 15 16 16 19 19
80 85 90 95 100 105
16 17 18 19 20 21
13 15 15 16 17 17
20 22 23 23 26 26
17 17 18 19 19 21
25 25 29 29 29 32
20 20 25 25 27 28
32 32 36 39 41 42
26 29 29 30 33 34
22 22 26 26 26
110 120 130 140 150 160
22 24 26 28 30 32
17 19 21 21 25 26
26 29 31 33 38 39
23 23 26 26 27 29
34 35 39 39 43 45
28 30 – – – –
42 46 – – – –
35 38 – – – –
– – – – – –
170 180 190 200 220 240
34 36 38 40 44 48
26 28 29 31 33
40 44 44 49 51
29 30 31 34 37 38
45 47 49 54 56 59
– – – – – –
– – – – – –
– – – – – –
– – – – – –
133
2 Angular contact ball bearings
Spacer width reduction for changing preloads in matched sets, ACD, ACX and ACE designs Table 13 Bearing size
Spacer adjustment Series 719 ACD Series 70 ACD 719 ACD/HC 70 ACD/HC 719 ACX 70 ACX and 719 ACX/HC and 70 ACX/HC
Series 72 ACD 72 ACD/HC 72 ACX and 72 ACX/HC
Series 719 ACE and 719 ACE/HC
Series 70 ACE and 70 ACE/HC
a
Bore diameter
Size
mm
–
µm
8 9 10 12 15 17
8 9 00 01 02 03
20 25 30 35 40 45
b
a
b
a
b
a
a
– – 2 2 3 3
– – 4 4 5 5
3 3 3 3 3 4
4 4 5 5 5 6
– – 3 3 5 5
– – 6 6 7 8
– – – – – –
– – – – – –
04 05 06 07 08 09
4 4 4 5 5 5
5 5 5 6 7 7
4 5 6 6 6 7
7 7 9 9 9 12
5 5 7 9 10 10
8 8 11 12 14 14
7 7 7 8 9 9
9 8 10 9 9 10
50 55 60 65 70 75
10 11 12 13 14 15
5 6 6 6 8 9
7 10 10 10 13 13
8 8 8 8 10 10
12 14 14 14 15 15
10 11 12 13 13 13
14 17 18 20 21 21
9 13 13 14 15 15
10 10 10 10 12 12
80 85 90 95 100 105
16 17 18 19 20 21
9 10 10 10 11 11
13 15 16 16 18 18
12 12 12 12 13 13
18 18 19 20 21 22
13 13 16 17 18 18
22 22 25 27 29 30
15 17 18 18 20 20
14 14 16 16 16
110 120 130 140 150 160
22 24 26 28 30 32
11 12 14 14 16 17
18 21 22 23 26 27
15 15 17 17 18 18
23 24 27 27 28 30
18 20 – – – –
30 32 – – – –
21 23 – – – –
– – – – – –
170 180 190 200 220 240
34 36 38 40 44 48
17 18 18 20 21
27 30 30 33 34
18 19 19 22 24 24
30 33 33 37 38 39
– – – – – –
– – – – – –
– – – – – –
– – – – – –
134
other cases, especially in grease-lubricated spindles, it is necessary to have spacers to allow grease to escape from the contact zone to reduce running temperature. In order to get the best performance from the bearings, spacers should not deform under load, and form errors should not be introduced, as these would affect the preload of the bearing sets. In general, the guidelines given in the form tolerance requirements for shaft and housing can be followed. For spacers in particular, the material should be hard enough to resist damage during handling, preferably the same hardness as bearing rings (i.e. around 60 HRC), but materials with 45 – 50 HRC would be adequate. The most important point concerns the parallelism of the faces and the width difference between the outer and inner spacer, in the same set of bearings. The parallelism should be kept within 1 – 2 µm. To obtain the lowest possible difference in width of the inner and outer spacer, the two spacers should be face ground together (one placed inside the other).
Fig 12
Cages High-precision angular contact ball bearings are as standard equipped with outer ring land riding fabric-reinforced phenolic resin cages. The cages are lightweight and designed to minimise centrifugal force, while ensuring an optimum lubricant flow throughout the ball-raceway contact. They are not identified in the bearing designation. New, better performance cages now being introduced are made of PEEK (polyether ether ketone) and are identified in the bearing designation by the suffix “TNH”. Fabric-reinforced phenolic resin ball guided cages and metallic machined cages are also available on request.
Example of spacers in between a group of two high-precision angular contact ball bearings matched back-to-back
135
2
2 Angular contact ball bearings
Speed ratings The limiting speeds quoted in the bearing tables are guideline values and are valid provided that the bearings are lightly loaded (P 0,06 C), that they are lightly preloaded by means of springs, and that the transport of heat away from the bearing position is good. The values for oil spot lubrication are maximum values and should be reduced for certain other methods of oil lubrication as mentioned in the chapter Speed (➔ page 23). The values for grease lubrication are also maximum values. Both apply to single bearings. When single bearings are adjusted against each other to a greater degree, e.g. to increase spindle stiffness, or if matched sets of two, three or four bearings are to be used, the speed rating values given in the tables must be reduced. Reduction factors to obtain guideline values for the appropriate conditions are given in Table 14 .
For special preloads please contact SKF. If the speed rating obtained from the above for matched bearing sets is inadequate, a simple design change, such as the inclusion of intermediate rings between the bearings will allow appreciable increases to be made (➔ fig 12 page 135). For sets of three bearings, for example, it should then be possible to run at the speed rating for paired bearings. Springs to preload the bearings may be beneficial. This type of preload is generally used for high-speed operation in order to obtain an even preload over the whole operating range of the machine.
Equivalent dynamic bearing load
Equivalent static bearing load
For bearings arranged singly or paired in tandem
For bearings arranged singly or paired in tandem
P = Fr P = XFr + YFa
P0 = 0,5 Fr + Y0Fa
when Fa/Fr e when Fa/Fr > e
Factor values are given in Table 15 page 138. When calculating bearing pairs, Fr and Fa represent the forces acting on the bearing pair. For bearings paired back-to-back or face-to-face P = Fr + Y1Fa P = XFr + Y2Fa
when Fa/Fr e when Fa/Fr > e
when P0 < Fr, P0 = Fr should be used. For bearings paired back-to-back or face-to-face P0 = Fr + Y0Fa The value of factor Y0 depends on the contact angle and can be obtained from Tables 15 and 16 . When calculating bearing pairs, Fr and Fa are the forces acting on the bearing pair.
Factor values are given in Table 16 page 138. When calculating bearing pairs, Fr and Fa represent the forces acting on the bearing pair.
Speed reduction factors for preloaded bearing sets of angular contact ball bearings Table 14 Bearing arrangement
Bearing design CD, CD/HC, ACD ACD/HC CX, CX/HC, ACX and ACX/HC Preload
All
CE, CE/HC, ACE and ACE/HC
Special preload
Preload
A
B
C
A
B
Set of 2 bearings paired in tandem
0,90
0,80
0,65
0,90
0,70
Set of 2 bearings paired back-to-back or face-to-face
0,80
0,70
0,55
0,75
0,60
Set of 3 bearings
0,70
0,55
0,35
0,65
0,40
Set of 4 bearings
0,65
0,45
0,25
0,55
0,30
136
Call SKF
137
2
2 Angular contact ball bearings Vibration from other machinery, traffic or during transportation may cause damage to bearings. In such cases, bearing life is not limited by the material fatigue, but by the permanent deformation produced in the contact between balls and raceways. A ball may be driven into the surface of the rings by the applied load. The same may happen for bearings sustaining heavy shock loads during a fraction of a revolution. As demands are high for running properties and life, permanent deformation of the bearing parts should be avoided at all times. The maximum load should therefore
Calculation of equivalent Designation systems of single bearing load for preloaded bearings and matched sets angular contact ball bearings
not exceed the equivalent static load obtained from the equation: P0 = C0/s0 where P0 = equivalent static bearing load, N C0 = basic static load rating, N s0 = static safety factor. For all-steel high-precision angular contact ball bearings, a minimum safety factor s0 of 3 is recommended. For hybrid bearings, a safety factor s0 of 3,4 can be used.
When calculating the equivalent bearing load for preloaded bearings, it is necessary to take the preload into account. The axial component of the load (Fa) is needed for the equivalent load calculation. It is obtained using the following equations when actual operating conditions are considered (the values obtained will be approximate). For bearing pairs under radial load and axially secured Fa = G m
The complete designation of a single bearing identifies the series, bore diameter, contact angle, and design, as well as the suffix indicating the tolerance class e.g. 71914 CD/P4A. The designation of bearing sets also includes suffixes indicating the number of bearings in the set, their arrangement and preload. Additional suffixes may be added to identify bearings incorporating special features, such as greases, special tolerances, etc. Please consult SKF for precise information. The designation scheme of SKF high-precision angular contact ball bearings is shown in Table 17 page 140.
For bearing pairs under radial load and preloaded by springs Fa = GA, B Calculation factors for single bearings and bearings paired in tandem Table 15 f0 Fa/C0
e
X
Y
For bearing pairs under axial load and axially secured
Calculation factors for bearings paired back-to-back or face-to-face
Y0
Table 16 2 f0 Fa/C0
e
X
Y1
Y2
Y0
Contact angle 15 degrees (suffix CD, CX and CE)
Contact angle 15 degrees (suffix CD, CX and CE)
< 0,178 0,357 0,714 1,07 1,43 2,14 3,57 5,35 > 7,14
< 0,178 0,357 0,714 1,07 1,43 2,14 3,57 5,35 > 7,14
0,38 0,4 0,43 0,46 0,47 0,5 0,55 0,56 0,56
0,44 0,44 0,44 0,44 0,44 0,44 0,44 0,44 0,44
1,47 1,40 1,30 1,23 1,19 1,12 1,02 1,00 1,00
0,46 0,46 0,46 0,46 0,46 0,46 0,46 0,46 0,46
0,38 0,4 0,43 0,46 0,47 0,5 0,55 0,56 0,56
0,72 0,72 0,72 0,72 0,72 0,72 0,72 0,72 0,72
1,65 1,57 1,46 1,38 1,34 1,26 1,14 1,12 1,12
2,39 2,28 2,11 2,00 1,93 1,82 1,66 1,63 1,63
0,92 0,92 0,92 0,92 0,92 0,92 0,92 0,92 0,92
Contact angle 25 degrees (suffix ACD, ACX and ACE)
Contact angle 25 degrees (suffix ACD, ACX and ACE)
–
–
0,68
0,41
0,87
Values of f0 are given in the bearing tables
138
0,38
0,68
0,67
0,92
1,41
Fa = Gm + 0,67 Ka Fa = K a
when Ka 3 Gm when Ka > 3 Gm
For bearing pairs under axial load and preloaded by springs Fa = GA, B + Ka where Fa = axial component of a bearing load, N GA, B = preload of a bearing pair, N Gm = preload on a mounted bearing pair, N Ka = external axial force acting on single bearing, N
0,76
Values of f0 are given in the bearing tables
139
2
2 Angular contact ball bearings Table 17
719 10 ACE TNH / HC P4A Q BC A
Product tables
Bearing series 719 Single row angular contact ball bearing, ISO Dimension Series 19 70 Single row angular contact ball bearing, ISO Dimension Series 10 72 Single row angular contact ball bearing, ISO Dimension Series 02
2
Bore diameter 8 8 mm bore diameter 9 9 mm bore diameter 00 10 mm bore diameter 01 12 mm bore diameter 02 15 mm bore diameter 03 17 mm bore diameter 04 (×5) 20 mm bore diameter I 48 (×5) 240 mm bore diameter Contact angle and internal design ACD, ACX 25° CD,CX 15° ACE 25° CE 15° Cage design and material — Outer ring land riding, fabric reinforced phenolic resin TNH Rolling element riding, glass fibre reinforced PEEK Rolling element material — Steel HC Silicon nitride (ceramic) Tolerance class P4A Dimensional accuracy to ISO class 4, running accuracy better than ISO class 4 PA9A Accuracy to ABMA class ABEC 9 Number of bearings in set D 2 bearings in matched set T 3 bearings in matched set Q 4 bearings in matched set Bearing arrangement in matched set B Back-to-back F Face-to-face T Tandem BT Back-to-back/tandem FT Face-to-face/tandem BC Back-to-back of pairs in tandem FC Face-to-face of pairs in tandem G For universal pairing Preload A B C G..
140
Light preload Medium preload Heavy preload Special preload, value in daN, e.g. G240
141
Standard high-precision angular contact ball bearings d 8 – 17 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD, CX and ACX
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
8
22
7
3 450
1 460
68
8,4
75 000
120 000
0,011
708 CX
8
11,8
17,6
0,3
0,1
6
10
20
20,1
0,3
0,1
9
24
7
3 710
1 730
80
8,8
67 000
100 000
0,014
709 CX
9
13,5
19,9
0,3
0,1
6
11
22
22,1
0,3
0,1
10
22 22 26 26 30 30
6 6 8 8 9 9
2 600 2 510 5 070 4 940 5 920 5 720
1 250 1 200 2 400 2 280 2 700 2 600
57 55 110 106 156 150
9,5 – 8,3 – 8,2 –
70 000 63 000 67 000 56 000 60 000 53 000
110 000 95 000 100 000 85 000 90 000 80 000
0,009 0,009 0,018 0,018 0,029 0,029
71900 CX 71900 ACX 7000 CX 7000 ACX 7200 CX 7200 ACX
10
13,6 13,6 15,1 15,1 16,8 16,8
17,8 17,8 21,3 21 23,3 23,3
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
5 7 6 8 7 9
12 12 12 12 15 15
20 20 24 24 25 25
20,5 20,5 24,1 24,1 27,1 27,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
12
24 24 28 28 32 32
6 6 8 8 10 10
2 910 2 760 5 530 5 270 6 760 6 630
1 530 1 460 2 750 2 650 3 100 3 000
71 67 127 122 180 176
9,8 – 8,7 – 8,5 –
67 000 60 000 60 000 53 000 53 000 48 000
100 000 90 000 90 000 80 000 80 000 70 000
0,01 0,01 0,02 0,02 0,036 0,036
71901 CX 71901 ACX 7001 CX 7001 ACX 7201 CX 7201 ACX
12
15,9 15,9 17,1 17,1 18,2 18,2
20,1 20,1 23,3 23,3 25,8 25,8
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
5 7 7 9 8 10
14 14 14 14 17 17
22 22 26 26 27 27
22,5 22,5 26,1 26,1 29,1 29,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
15
28 28 32 32 35 35
7 7 9 9 11 11
4 360 4 160 6 240 5 920 7 410 7 150
2 400 2 280 3 450 3 250 3 650 3 550
110 104 160 153 212 204
9,6 – 9,3 – 8,5 –
56 000 50 000 50 000 45 000 48 000 43 000
85 000 75 000 75 000 67 000 70 000 63 000
0,015 0,015 0,028 0,028 0,043 0,043
71902 CX 71902 ACX 7002 CX 7002 ACX 7202 CX 7202 ACX
15
19,1 19,1 20,6 20,6 21,5 21,5
23,9 23,9 26,8 26,5 29,1 29,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
6 9 8 10 9 12
17 17 17 17 20 20
26 26 30 30 30 30
26,5 26,5 30,1 30,1 33 33
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
17
30 30 35 35 40 40
7 7 10 10 12 12
4 490 4 360 6 500 6 180 9 230 8 840
2 650 2 500 3 800 3 650 4 650 4 500
122 116 176 170 270 260
9,8 – 9,1 – 8,5 –
50 000 45 000 48 000 40 000 43 000 38 000
75 000 67 000 70 000 60 000 63 000 56 000
0,017 0,017 0,037 0,037 0,062 0,062
71903 CX 71903 ACX 7003 CX 7003 ACX 7203 CX 7203 ACX
17
21,1 21,1 22,9 22,9 24,2 24,2
25,9 25,9 29,6 29,2 32,8 32,8
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
7 9 9 11 10 13
19 19 19 19 22 22
28 28 33 33 35 35
28,5 28,5 33,4 33,4 38 38
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
142
143
Standard high-precision angular contact ball bearings d 20 – 40 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD, CX and ACX
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
20
37 37 42 42 47 47
9 9 12 12 14 14
6 630 6 240 10 400 9 950 12 400 11 900
4 050 3 900 6 100 5 850 6 550 6 200
186 180 280 270 375 360
9,8 – 9,2 – 8,7 –
43 000 38 000 38 000 34 000 36 000 32 000
63 000 56 000 56 000 50 000 53 000 48 000
0,035 0,035 0,065 0,065 0,1 0,1
71904 CX 71904 ACX 7004 CX 7004 ACX 7204 CX 7204 ACX
20
25,4 25,4 26,9 26,9 29,1 29,1
31,6 31,6 35,1 35,1 38,7 38,7
0,3 0,3 0,6 0,6 1 1
0,15 0,15 0,3 0,3 0,3 0,3
8 11 10 13 12 15
22 22 25 25 26 26
35 35 37 37 41 41
35,5 35,5 39,1 39,1 44,1 44,1
0,3 0,3 0,6 0,6 1 1
0,1 0,1 0,3 0,3 0,3 0,3
25
42 42 47 47 52 52
9 9 12 12 15 15
7 020 6 630 11 400 10 800 14 000 13 500
4 800 4 550 7 350 7 100 8 150 7 800
220 212 340 325 475 450
10 – 9,6 – 9,1 –
36 000 32 000 34 000 28 000 30 000 26 000
53 000 48 000 50 000 43 000 45 000 40 000
0,042 0,042 0,075 0,075 0,14 0,14
71905 CX 71905 ACX 7005 CX 7005 ACX 7205 CX 7205 ACX
25
30,4 30,4 31,9 31,9 34,1 34,1
36,6 36,6 40,1 40,1 43,7 43,7
0,3 0,3 0,6 0,6 1 1
0,15 0,15 0,3 0,3 0,3 0,3
9 12 11 15 13 17
27 27 30 30 31 31
40 40 42 42 46 46
40,5 40,5 44,1 44,1 49,1 49,1
0,3 0,3 0,6 0,6 1 1
0,1 0,1 0,3 0,3 0,3 0,3
30
47 47 55 55 62 62
9 9 13 13 16 16
7 150 6 760 14 600 14 000 24 200 23 400
5 200 4 900 10 000 9 650 16 000 15 300
240 228 465 440 670 640
10 – 9,4 – 14 –
30 000 26 000 28 000 24 000 24 000 20 000
45 000 40 000 43 000 38 000 38 000 34 000
0,048 0,048 0,11 0,11 0,19 0,19
71906 CX 71906 ACX 7006 CX 7006 ACX 7206 CD 7206 ACD
30
35,4 35,4 38,1 38,1 40,3 40,3
41,6 41,6 46,9 46,9 51,7 51,7
0,3 0,3 1 1 1 1
0,15 0,15 0,3 0,3 0,3 0,3
10 14 12 17 14 19
32 32 36 36 36 36
45 45 49 49 56 56
45,5 45,5 52,1 52,1 60 60
0,3 0,3 1 1 1 1
0,1 0,1 0,3 0,3 0,3 0,3
35
55 55 62 62 72 72
10 10 14 14 17 17
9 750 9 230 15 600 14 800 31 900 30 700
6 550 6 200 9 500 9 000 21 600 20 800
275 260 400 380 915 880
10 – 9,7 – 14 –
26 000 22 000 22 000 19 000 20 000 18 000
40 000 36 000 36 000 32 000 34 000 30 000
0,074 0,074 0,15 0,15 0,28 0,28
71907 CD 71907 ACD 7007 CD 7007 ACD 7207 CD 7207 ACD
35
41,2 41,2 43,7 43,7 47 47
48,8 48,8 53,3 53,3 60 60
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,3 0,3
11 16 14 19 16 21
40 40 41 41 42 42
50 50 56 56 65 65
53,8 53,8 60 60 70 70
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,3 0,3
40
62 62 68 68 80 80
12 12 15 15 18 18
12 400 11 700 16 800 15 900 41 000 39 000
8 500 8 000 11 000 10 400 28 000 27 000
360 340 465 440 1 180 1 140
10 – 10 – 14 –
20 000 18 000 19 000 18 000 18 000 16 000
34 000 30 000 32 000 30 000 30 000 26 000
0,11 0,11 0,19 0,19 0,36 0,36
71908 CD 71908 ACD 7008 CD 7008 ACD 7208 CD 7208 ACD
40
46,7 46,7 49,2 49,2 53 53
55,3 55,3 58,8 58,8 67 67
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
13 18 15 20 17 23
45 45 46 46 47 47
57 57 62 62 73 73
60,8 60,8 66 66 75 75
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
144
145
Standard high-precision angular contact ball bearings d 45 – 65 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
45
68 68 75 75 85 85
12 12 16 16 19 19
13 000 12 400 28 600 27 600 42 300 41 000
9 500 9 000 22 400 21 600 31 000 30 000
400 380 950 900 1 320 1 250
11 – 15 – 14 –
19 000 17 000 18 000 16 000 17 000 15 000
32 000 28 000 30 000 26 000 28 000 24 000
0,13 0,13 0,23 0,23 0,41 0,41
71909 CD 71909 ACD 7009 CD 7009 ACD 7209 CD 7209 ACD
45
52,2 52,2 54,7 54,7 57,5 57,5
60,8 60,8 65,3 65,3 72,5 72,5
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
14 19 16 22 18 25
50 50 51 51 52 52
63 63 69 69 78 78
66,8 66,8 73 73 80 80
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
50
72 72 80 80 90 90
12 12 16 16 20 20
13 500 12 700 29 600 28 100 44 900 42 300
10 400 9 800 24 000 23 200 34 000 32 500
440 415 1 020 980 1 430 1 390
11 – 15 – 15 –
17 000 16 000 17 000 15 000 16 000 14 000
28 000 26 000 28 000 24 000 26 000 22 000
0,13 0,13 0,25 0,25 0,46 0,46
71910 CD 71910 ACD 7010 CD 7010 ACD 7210 CD 7210 ACD
50
56,7 56,7 59,7 59,7 62,5 62,5
65,3 65,3 70,3 70,3 77,5 77,5
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
14 20 17 17 20 27
55 55 56 56 57 57
67 67 74 74 83 83
70,8 70,8 78 78 85 85
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
55
80 80 90 90 100 100
13 13 18 18 21 21
19 500 18 200 39 700 37 100 55 300 52 700
14 600 13 700 32 500 31 000 43 000 40 500
620 585 1 370 1 320 1 800 1 730
10 – 15 – 14 –
16 000 15 000 15 000 14 000 14 000 13 000
26 000 24 000 24 000 22 000 22 000 20 000
0,18 0,18 0,37 0,37 0,61 0,61
71911 CD 71911 ACD 7011 CD 7011 ACD 7211 CD 7211 ACD
55
62,7 62,7 66,3 66,3 69 69
72,3 72,3 78,7 78,7 85,9 85,9
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
16 22 19 26 21 29
61 61 62 62 64 64
74 74 83 83 91 91
78 78 86 86 95 95
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
60
85 85 95 95 110 110
13 13 18 18 22 22
19 900 18 600 40 300 39 000 67 600 63 700
15 300 14 600 34 500 33 500 53 000 50 000
655 620 1 500 1 400 2 240 2 120
11 – 15 – 14 –
15 000 14 000 14 000 13 000 13 000 11 000
24 000 22 000 22 000 20 000 20 000 18 000
0,19 0,19 0,4 0,4 0,8 0,8
71912 CD 71912 ACD 7012 CD 7012 ACD 7212 CD 7212 ACD
60
67,7 67,7 71,3 71,3 75,6 75,6
77,3 77,3 83,7 83,7 94,4 94,4
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
16 23 20 27 23 31
66 66 67 67 69 69
79 79 88 88 101 101
83 83 91 91 105 105
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
65
90 90 100 100 120 120
13 13 18 18 23 23
20 800 19 500 41 600 39 000 76 100 72 800
17 000 16 000 37 500 35 500 60 000 57 000
710 680 1 600 1 500 2 500 2 400
11 – 16 – 14 –
14 000 13 000 14 000 12 000 12 000 10 000
22 000 20 000 22 000 19 000 19 000 17 000
0,21 0,21 0,42 0,42 1 1
71913 CD 71913 ACD 7013 CD 7013 ACD 7213 CD 7213 ACD
65
72,7 72,7 76,3 76,3 82,5 82,5
82,3 82,3 88,7 88,7 103 103
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
17 25 20 28 24 33
71 71 72 72 74 74
84 84 93 93 111 111
88 88 96 96 115 115
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
146
147
Standard high-precision angular contact ball bearings d 70 – 90 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
70
100 100 110 110 125 125
16 16 20 20 24 24
34 500 32 500 52 000 48 800 79 300 76 100
34 000 32 500 45 500 44 000 64 000 62 000
1 430 1 370 1 930 1 860 2 750 2 600
16 – 15 – 15 –
13 000 11 000 12 000 10 000 11 000 9 500
20 000 18 000 19 000 17 000 18 000 16 000
0,33 0,33 0,59 0,59 1,1 1,1
71914 CD 71914 ACD 7014 CD 7014 ACD 7214 CD 7214 ACD
70
79,3 79,3 82,9 82,9 87 87
90,7 90,7 97,1 97,1 108 108
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
19 28 22 31 25 35
76 76 77 77 79 79
94 94 103 103 116 116
98 98 106 106 120 120
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
75
105 105 115 115 130 130
16 16 20 20 25 25
35 800 33 800 52 700 49 400 83 200 79 300
37 500 35 500 49 000 46 500 69 500 67 000
1 560 1 500 2 080 1 960 2 900 2 800
16 – 16 – 15 –
12 000 10 000 11 000 9 500 10 000 9 000
19 000 17 000 18 000 16 000 17 000 15 000
0,35 0,35 0,62 0,62 1,2 1,2
71915 CD 71915 ACD 7015 CD 7015 ACD 7215 CD 7215 ACD
75
84,3 84,3 87,9 87,9 92 92
95,7 95,7 103 103 113 113
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
20 29 23 32 26 37
81 81 82 82 84 84
99 99 108 108 121 121
103 103 111 111 125 125
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
80
110 110 125 125 140 140
16 16 22 22 26 26
36 400 34 500 65 000 62 400 97 500 92 300
39 000 36 500 61 000 58 500 81 500 78 000
1 660 1 560 2 550 2 450 3 350 3 200
16 – 16 – 15 –
11 000 9 500 10 000 9 000 9 500 8 500
18 000 16 000 17 000 15 000 16 000 14 000
0,37 0,37 0,85 0,85 1,45 1,45
71916 CD 71916 ACD 7016 CD 7016 ACD 7216 CD 7216 ACD
80
89,3 89,3 94,4 94,4 98,6 98,6
101 101 111 111 122 122
1 1 1,1 1,1 2 2
0,3 0,3 0,6 0,6 1 1
21 30 25 35 28 39
86 86 87 87 90 90
104 104 118 118 130 130
108 108 121 121 134 134
1 1 1 1 2 2
0,3 0,3 0,6 0,6 1 1
85
120 120 130 130 150 150
18 18 22 22 28 28
46 200 43 600 67 600 63 700 99 500 95 600
48 000 45 500 65 500 62 000 88 000 85 000
2 040 1 930 2 650 2 500 3 450 3 350
16 – 16 – 15 –
10 000 9 000 9 500 8 500 9 000 8 000
17 000 15 000 16 000 14 000 15 000 13 000
0,53 0,53 0,89 0,89 1,8 1,8
71917 CD 71917 ACD 7017 CD 7017 ACD 7217 CD 7217 ACD
85
95,8 95,8 99,4 106 100 100
110 110 116 130 115 115
1,1 1,1 1,1 2 1,1 1,1
0,6 0,6 0,6 1 0,6 0,6
23 23 36 30 23 23
92 92 92 95 97 97
113 113 123 140 118 118
115 115 126 144 120 120
1 1 1 2 1 1
0,6 0,6 0,6 1 0,6 0,6
90
125 125 140 140 160 160
18 18 24 24 30 30
47 500 44 200 79 300 74 100 127 000 121 000
51 000 48 000 76 500 72 000 112 000 106 000
2 080 1 960 3 000 2 850 4 250 4 050
16 – 16 – 15 –
9 500 8 500 9 000 8 000 8 500 7 500
16 000 14 000 15 000 13 000 14 000 12 000
0,55 0,55 1,15 1,15 2,25 2,25
71918 CD 71918 ACD 7018 CD 7018 ACD 7218 CD 7218 ACD
90
100 100 106 106 111 111
115 115 124 124 139 139
1,1 1,1 1,5 2 2 2
0,6 0,6 0,6 1 1 1
23 34 39 32 32 44
97 97 99 100 100 100
118 118 131 150 150 150
120 120 135 135 154 154
1 1 1,5 1,5 2 2
0,6 0,6 0,6 0,6 1 1
148
149
Standard high-precision angular contact ball bearings d 95 – 120 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
95
130 130 145 145 170 170
18 18 24 24 32 32
49 400 46 200 81 900 76 100 138 000 133 000
55 000 52 000 80 000 76 500 120 000 114 000
2 200 2 080 3 100 2 900 4 400 4 250
16 – 16 – 15 –
9 000 8 500 8 500 8 000 8 000 7 500
15 000 14 000 14 000 13 000 13 000 12 000
0,58 0,58 1,2 1,2 2,7 2,7
71919 CD 71919 ACD 7019 CD 7019 ACD 7219 CD 7219 ACD
95
105 105 111 111 118 118
120 120 129 129 147 147
1,1 1,1 1,5 1,5 2,1 2,1
0,6 0,6 0,6 0,6 1,1 1,1
24 35 28 40 34 47
102 102 104 104 107 107
123 123 136 136 158 158
125 125 140 140 163 163
1 1 1,5 1,5 2 2
0,6 0,6 0,6 0,6 1 1
100
140 140 150 150 180 180
20 20 24 24 34 34
60 500 57 200 83 200 79 300 156 000 148 000
65 500 63 000 85 000 80 000 137 000 129 000
2 550 2 400 3 200 3 050 4 900 4 650
16 – 16 – 15 –
8 500 8 000 8 500 7 500 7 500 7 000
14 000 13 000 14 000 12 000 12 000 11 000
0,8 0,8 1,25 1,25 3,25 3,25
71920 CD 71920 ACD 7020 CD 7020 ACD 7220 CD 7220 ACD
100
112 112 116 116 124 124
128 128 134 134 155 155
1,1 1,1 1,5 1,5 2,1 2,1
0,6 0,6 0,6 0,6 1,1 1,1
26 38 29 41 36 50
107 107 109 109 112 112
133 133 141 141 168 168
135 135 145 145 173 173
1 1 1,5 1,5 2 2
0,6 0,6 0,6 0,6 1 1
105
145 145 160 160 190 190
20 20 26 26 36 36
61 800 57 200 95 600 90 400 172 000 163 000
69 500 65 500 96 500 93 000 153 000 146 000
2 600 2 500 3 600 3 400 5 300 5 100
16 – 16 – 15 –
8 500 7 500 8 000 7 500 7 500 6 700
14 000 12 000 13 000 12 000 12 000 10 000
0,82 0,82 1,6 1,6 3,85 3,85
71921 CD 71921 ACD 7021 CD 7021 ACD 7221 CD 7221 ACD
105
117 117 122 122 131 131
133 133 143 143 164 164
1,1 1,1 2 2 2,1 2,1
0,6 0,6 1 1 1,1 1,1
27 39 31 44 38 53
112 112 115 115 117 117
138 138 150 150 178 178
140 140 154 154 183 183
1 1 2 2 2 2
0,6 0,6 1 1 1 1
110
150 150 170 170 200 200
20 20 28 28 38 38
62 400 58 500 111 000 104 000 178 000 168 000
72 000 68 000 108 000 104 000 166 000 160 000
2 700 2 550 3 900 3 750 5 600 5 400
17 – 16 – 15 –
8 000 7 500 7 500 7 000 7 000 6 700
13 000 12 000 12 000 11 000 11 000 10 000
0,86 0,86 1,95 1,95 4,55 4,55
71922 CD 71922 ACD 7022 CD 7022 ACD 7222 CD 7222 ACD
110
122 122 129 129 138 138
138 138 151 151 172 172
1,1 1,1 2 2 2,1 2,1
0,6 0,6 1 1 1,1 1,1
27 40 33 47 40 55
117 117 120 120 122 122
143 143 160 160 188 188
145 145 164 164 193 193
1 1 2 2 2 2
0,6 0,6 1 1 1 1
120
165 165 180 180 215 215
22 22 28 28 40 40
78 000 72 800 114 000 111 000 199 000 190 000
91 500 86 500 122 000 116 000 193 000 183 000
3 250 3 050 4 250 4 000 6 300 6 000
16 – 16 – 15 –
7 500 7 000 7 000 6 700 6 700 6 000
12 000 11 000 11 000 10 000 10 000 9 000
1,15 1,15 2,1 2,1 5,4 5,4
71924 CD 71924 ACD 7024 CD 7024 ACD 7224 CD 7224 ACD
120
133 133 139 139 150 150
152 152 161 161 187 187
1,1 1,1 2 2 2,1 2,1
0,6 0,6 1 1 1,1 1,1
30 44 34 49 43 60
127 127 130 130 132 132
158 158 170 170 203 203
160 160 174 174 208 208
1 1 2 2 2 2
0,6 0,6 1 1 1 1
150
151
Standard high-precision angular contact ball bearings d 130 – 190 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
130
180 180 200 200
24 24 33 33
92 300 87 100 148 000 140 000
108 000 102 000 156 000 150 000
3 650 3 450 5 200 4 900
16 – 16 –
7 000 6 700 6 700 6 000
11 000 10 000 10 000 9 000
1,55 1,55 3,2 3,2
71926 CD 71926 ACD 7026 CD 7026 ACD
130
145 145 152 152
165 165 178 178
1,5 1,5 2 2
0,6 0,6 1 1
33 48 39 55
139 139 140 140
171 171 190 190
175 175 194 194
1,5 1,5 2 2
0,6 0,6 1 1
140
190 190 210 210
24 24 33 33
95 600 90 400 153 000 146 000
116 000 110 000 166 000 156 000
3 900 3 650 5 300 5 100
17 – 16 –
6 700 6 000 6 700 5 600
10 000 9 000 10 000 8 500
1,65 1,65 3,4 3,4
71928 CD 71928 ACD 7028 CD 7028 ACD
140
155 155 162 162
175 175 188 188
1,5 1,5 2 2
0,6 0,6 1 1
34 51 40 58
149 149 150 150
181 181 200 200
185 185 204 204
1,5 1,5 2 2
0,6 0,6 1 1
150
210 210 225 225
28 28 35 35
125 000 119 000 172 000 163 000
146 000 140 000 190 000 180 000
4 750 4 500 5 850 5 600
16 – 16 –
6 300 5 000 6 000 5 300
9 500 8 500 9 000 8 000
2,55 2,55 4,15 4,15
71930 CD 71930 ACD 7030 CD 7030 ACD
150
168 168 174 174
192 192 201 201
2 2 2,1 2,1
1 1 1 1
38 56 43 62
160 160 162 162
200 200 213 213
204 204 219 219
2 2 2 2
1 1 1 1
160
220 220 240 240
28 28 38 38
130 000 124 000 195 000 182 000
160 000 153 000 216 000 204 000
5 000 4 750 6 550 6 200
16 – 16 –
6 000 5 600 5 600 5 000
9 000 8 500 8 500 7 500
2,7 2,7 5,1 5,1
71932 CD 71932 ACD 7032 CD 7032 ACD
160
178 178 185 185
202 202 215 215
2 2 2,1 2,1
1 1 1 1
40 58 46 66
170 170 172 172
210 210 228 228
214 214 234 234
2 2 2 2
1 1 1 1
170
230 230 260 260
28 28 42 42
133 000 124 000 212 000 199 000
166 000 156 000 245 000 232 000
5 100 4 800 7 100 6 700
16 – 16 –
5 600 5 000 5 300 4 800
8 500 7 500 8 000 7 000
2,85 2,85 6,85 6,85
71934 CD 71934 ACD 7034 CD 7034 ACD
170
188 188 199 199
212 212 231 231
2 2 2,1 2,1
1 1 1,1 1,1
41 61 50 71
180 180 182 182
220 220 248 248
224 224 253 253
2 2 2 2
1 1 1 1
180
250 250 280 280
33 33 46 46
168 000 159 000 242 000 229 000
212 000 200 000 290 000 275 000
6 100 5 850 8 150 7 650
16 – 16 –
5 300 4 800 5 000 4 300
8 000 7 000 7 500 6 300
4,2 4,2 8,9 8,9
71936 CD 71936 ACD 7036 CD 7036 ACD
180
201 201 212 212
229 229 248 248
2 2 2,1 2,1
1 1 1,1 1,1
45 67 54 77
190 190 192 192
240 240 268 268
244 244 273 273
2 2 2 2
1 1 1 1
190
260 260 290 290
33 33 46 46
172 000 163 000 247 000 234 000
220 000 208 000 300 000 290 000
6 200 5 850 8 300 8 000
16 – 16 –
5 000 4 500 4 800 4 300
7 500 6 700 7 000 6 300
4,35 4,35 9,35 9,35
71938 CD 71938 ACD 7038 CD 7038 ACD
190
211 211 222 222
239 239 258 258
2 2 2,1 2,1
1 1 1,1 1,1
47 69 55 79
200 200 202 202
250 250 278 278
254 254 283 283
2 2 2 2
1 1 1 1
152
153
Standard high-precision angular contact ball bearings d 200 – 240 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3
da
Da
d d1
D D1
ra
ra
r1
2
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
200
280 280 310 310
38 38 51 51
208 000 199 000 296 000 281 000
265 000 250 000 390 000 365 000
7 200 6 800 10 200 9 800
16 – 16 –
4 800 4 300 4 500 4 000
7 000 6 300 6 700 6 000
6,1 6,1 12 12
71940 CD 71940 ACD 7040 CD 7040 ACD
200
224 224 234 234
256 256 276 276
2,1 2,1 2,1 2,1
1 1 1,1 1,1
51 75 60 85
212 212 212 212
268 268 298 298
274 274 303 303
2 2 2 2
1 1 1 1
220
300 300 340 340
38 38 56 56
221 000 208 000 338 000 319 000
300 000 285 000 455 000 440 000
7 800 7 500 11 600 11 000
16 – 16 –
4 300 3 800 4 000 3 600
6 300 5 600 6 000 5 300
6,6 6,6 16 16
71944 CD 71944 ACD 7044 CD 7044 ACD
220
244 244 258 258
276 276 302 302
2,1 2,1 3 3
1 1 1,1 1,1
54 80 66 94
232 232 234 234
288 288 326 326
294 294 333 333
2 2 2,5 2,5
1 1 1 1
240
360 360
56 56
345 000 490 000 325 000 465 000
12 000 11 400
16 –
3 800 3 200
5 600 4 800
17 17
7048 CD 7048 ACD
240
278 278
322 322
3 3
1,1 1,1
68 98
254 254
346 346
353 353
2,5 2,5
1 1
154
155
High speed high-precision angular contact ball bearings d 20 – 50 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
20
37 37 42 42
9 9 12 12
4 680 4 420 7 020 6 760
2 120 2 040 3 050 2 900
90 85 129 122
7 – 6,5 –
56 000 49 000 51 600 45 000
86 000 77 000 79 000 70 500
0,035 0,035 0,063 0,063
71904 CE 71904 ACE 7004 CE 7004 ACE
20
25,6 25,6 27,2 27,2
31,4 31,4 34,8 34,8
0,3 0,3 0,6 0,6
0,2 0,2 0,6 0,6
8,4 11,3 10,3 13,4
22 22 25 25
35 35 37 37
35,8 35,8 40,3 40,3
0,3 0,3 0,6 0,6
0,1 0,1 0,6 0,6
25
42 42 47 47
9 9 12 12
5 270 4 940 7 800 7 410
2 700 2 550 3 750 3 550
114 108 156 150
7,2 – 6,8 –
47 500 41 500 44 400 38 800
73 000 65 500 68 000 61 000
0,042 0,042 0,073 0,073
71905 CE 71905 ACE 7005 CE 7005 ACE
25
30,6 30,6 32,2 32,2
36,4 36,4 39,9 39,9
0,3 0,3 0,6 0,6
0,2 0,2 0,6 0,6
9,1 12,5 10,9 14,6
27 27 30 30
40 40 42 42
40,8 40,8 45,1 45,1
0,3 0,3 0,6 0,6
0,1 0,1 0,6 0,6
30
47 47 55 55
9 9 13 13
5 590 5 270 10 100 9 560
3 100 2 900 5 100 4 900
132 125 216 208
7,4 – 6,9 –
41 500 36 200 37 600 32 800
63 500 57 000 57 600 51 600
0,048 0,048 0,108 0,108
71906 CE 71906 ACE 7006 CE 7006 ACE
30
35,6 35,6 38,3 38,3
41,4 41,4 46,8 46,8
0,3 0,3 1 1
0,2 0,2 1 1
9,7 13,6 12,3 16,6
32 32 35 35
45 45 50 50
45,8 45,8 52,8 52,8
0,3 0,3 1 1
0,1 0,1 1 1
35
55 55 62 62
10 10 14 14
7 610 7 150 10 800 10 400
4 400 4 150 6 000 5 700
186 176 255 240
7,3 – 7,1 –
35 500 31 000 33 000 28 800
54 400 48 500 50 500 45 300
0,075 0,075 0,147 0,147
71907 CE 71907 ACE 7007 CE 7007 ACE
35
41,6 41,6 44,3 44,3
48,4 48,4 52,8 52,8
0,6 0,6 1 1
0,2 0,2 1 1
11,1 15,7 13,6 18,5
40 40 41 41
50 50 56 56
53,8 53,8 59,5 59,5
0,6 0,6 1 1
0,1 0,1 1 1
40
62 62 68 68
12 12 15 15
9 560 9 230 11 700 11 100
5 700 5 400 6 800 6 550
240 228 290 275
7,3 – 7,3 –
31 300 27 400 29 600 25 800
48 000 43 000 45 300 40 600
0,109 0,109 0,184 0,184
71908 CE 71908 ACE 7008 CE 7008 ACE
40
47,1 47,1 49,8 49,8
54,9 54,9 58,3 58,3
0,6 0,6 1 1
0,2 0,2 1 1
12,9 18,1 14,9 20,3
45 45 46 46
57 57 62 62
60,8 60,8 65,3 65,3
0,6 0,6 1 1
0,1 0,1 1 1
45
68 68 75 75
12 12 16 16
10 100 9 560 14 000 13 300
6 400 6 100 8 500 8 000
270 255 360 340
7,5 – 7,3 –
28 300 24 500 26 600 23 300
43 100 38 600 40 800 36 600
0,129 0,129 0,231 0,231
71909 CE 71909 ACE 7009 CE 7009 ACE
45
52,6 52,6 55,3 55,3
60,4 60,4 64,8 64,8
0,6 0,6 1 1
0,2 0,2 1 1
13,7 19,4 16,2 22,2
50 50 51 51
63 63 69 69
66,8 66,8 72 72
0,6 0,6 1 1
0,1 0,1 1 1
50
72 72 80 80
12 12 16 16
10 600 9 950 14 800 14 000
7 100 6 700 9 500 9 000
300 285 400 380
7,6 – 7,4 –
26 200 22 900 24 600 21 500
40 000 36 000 37 600 33 800
0,131 0,131 0,251 0,251
71910 CE 71910 ACE 7010 CE 7010 ACE
50
57,1 57,1 60,3 60,3
64,9 64,9 69,8 69,8
0,6 0,6 1 1
0,2 0,2 1 1
14,3 20,4 16,9 23,4
55 55 55 55
67 67 74 74
70,8 70,8 76,8 76,8
0,6 0,6 1 1
0,1 0,1 1 1
156
157
High speed high-precision angular contact ball bearings d 55 – 85 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
55
80 80 90 90
13 13 18 18
15 300 14 600 15 600 14 800
10 000 9 500 10 600 10 000
425 400 450 425
7,5 – 7,5 –
23 600 20 600 22 000 19 200
36 000 32 000 33 700 30 300
0,175 0,175 0,387 0,387
71911 CE 71911 ACE 7011 CE 7011 ACE
55
62,7 62,7 67,8 67,7
72,3 72,3 77,3 77,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
15,7 22,5 18,9 26,2
61 61 62 62
74 74 82 82
78 78 86,4 86,4
1 1 1 1
0,3 0,3 1 1
60
85 85 95 95
13 13 18 18
15 600 14 800 16 300 15 300
10 600 10 000 11 600 11 000
450 425 490 465
7,5 – 7,6 –
22 000 19 100 20 600 18 000
33 600 30 000 31 600 28 300
0,187 0,187 0,415 0,415
71912 CE 71912 ACE 7012 CE 7012 ACE
60
67,7 67,7 72,8 72,8
77,3 77,3 82,3 82,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
16,4 23,7 19,5 27,3
66 66 67 67
79 79 88 88
83 83 91 91
1 1 1 1
0,3 0,3 1 1
65
90 90 100 100
13 13 18 18
16 300 15 300 16 800 15 900
11 600 11 000 12 700 12 000
490 465 540 510
7,6 – 7,7 –
20 500 18 000 19 300 16 900
31 500 28 000 29 600 26 600
0,2 0,2 0,443 0,443
71913 CE 71913 ACE 7013 CE 7013 ACE
65
72,7 72,7 77,8 77,8
82,3 82,3 87,3 87,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
17,0 24,8 20,2 28,5
71 71 72 72
84 84 93 93
88 88 96 96
1 1 1 1
0,3 0,3 1 1
70
100 100 110 110
16 16 20 20
21 600 20 300 22 500 21 600
15 000 14 300 16 600 15 600
640 600 695 670
7,5 – 7,5 –
18 500 16 400 17 700 15 500
28 700 25 500 27 200 24 400
0,324 0,324 0,607 0,607
71914 CE 71914 ACE 7014 CE 7014 ACE
70
79,2 79,2 84,3 84,3
90,8 90,8 95,8 95,8
1 1 1,1 1,1
0,3 0,3 1,1 1,1
19,6 28,1 22,2 31,3
76 76 77 77
94 94 103 103
98 98 106 106
1 1 1 1
0,3 0,3 1 1
75
105 105 115 115
16 16 20 20
22 500 21 600 22 900 21 600
16 600 15 600 17 300 16 300
695 670 735 695
7,5 – 7,6 –
17 500 15 500 16 800 14 700
27 000 24 000 25 700 23 100
0,345 0,345 0,639 0,639
71915 CE 71915 ACE 7015 CE 7015 ACE
75
84,2 84,2 89,3 89,3
95,8 95,8 100,8 100,8
1 1 1,1 1,1
0,3 0,3 1,1 1,1
20,2 29,3 22,9 32,5
81 81 82 82
99 99 108 108
103 103 111 111
1 1 1 1
0,3 0,3 1 1
80
110 110 125 125
16 16 22 22
22 900 21 600 29 100 27 600
17 300 16 300 21 600 20 400
735 695 900 850
7,6 – 7,5 –
16 600 14 500 15 600 13 600
25 500 23 000 23 900 21 400
0,363 0,363 0,846 0,846
71916 CE 71916 ACE 7016 CE 7016 ACE
80
89,2 89,2 95,9 95,9
100,8 100,8 109,2 109,2
1 1 1,1 1,1
0,3 0,3 1,1 1,1
20,9 30,5 24,9 35,2
86 86 87 87
104 104 118 118
108 108 121 121
1 1 1 1
0,3 0,3 1 1
85
120 120 130 130
18 18 22 22
29 100 27 600 29 600 28 100
21 600 20 400 22 800 21 600
900 850 930 880
7,5 – 7,6 –
15 500 13 500 14 800 13 000
23 800 21 200 22 700 20 400
0,516 0,516 0,887 0,887
71917 CE 71917 ACE 7017 CE 7017 ACE
85
95,8 95,8 100,9 100,9
109,2 109,2 114,2 114,2
1,1 1,1 1,1 1,1
0,6 0,6 1,1 1,1
22,9 33,2 25,6 36,4
92 92 92 92
113 113 123 123
115 115 126 126
1 1 1 1
0,6 0,6 1 1
158
159
High speed high-precision angular contact ball bearings d 90 – 120 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
90
125 125 140 140
18 18 24 24
29 600 28 100 37 100 35 100
22 800 21 600 28 000 26 500
930 880 1 100 1 040
7,6 – 7,5 –
14 500 13 000 13 900 12 100
22 600 20 200 21 300 19 000
0,54 0,54 1,146 1,146
71918 CE 71918 ACE 7018 CE 7018 ACE
90
100,8 100,8 107,4 107,4
114,2 114,2 122,7 122,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
23,6 34,4 27,6 39,2
97 97 99 99
118 118 131 131
120 120 135 135
1 1 1,5 1,5
0,6 0,6 1,5 1,5
95
130 130 145 145
18 18 24 24
31 200 29 600 37 700 35 800
24 500 23 200 29 000 28 000
980 930 1 140 1 080
7,6 – 7,5 –
14 000 12 300 13 300 11 600
21 500 19 000 20 400 18 300
0,57 0,57 1,195 1,195
71919 CE 71919 ACE 7019 CE 7019 ACE
95
105,8 105,8 112,4 112,4
119,2 119,2 127,7 127,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
24,3 35,6 28,3 40,4
102 102 104 104
123 123 136 136
125 125 140 140
1 1 1,5 1,5
0,6 0,6 1,5 1,5
100
140 140 150 150
20 20 24 24
37 700 35 800 39 000 36 400
29 000 28 000 30 500 29 000
1 140 1 080 1 160 1 100
7,5 – 7,6 –
13 100 11 500 12 800 11 200
20 200 18 000 19 600 17 500
0,773 0,773 1,245 1,245
71920 CE 71920 ACE 7020 CE 7020 ACE
100
112,3 112,3 117,4 117,4
127,7 127,7 132,7 132,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
26,3 38,4 29,0 41,5
107 107 109 109
133 133 141 141
135 135 145 145
1 1 1,5 1,5
0,6 0,6 1,5 1,5
105
145 145
20 20
39 000 36 400
30 500 29 000
1 160 1 100
7,6 –
12 800 11 200
19 500 17 500
0,805 0,805
71921 CE 71921 ACE
105
117,3 117,3
132,7 132,7
1,1 1,1
0,6 0,6
27,0 39,5
112 112
138 138
140 140
1 1
0,6 0,6
110
150 150
20 20
39 700 37 100
32 000 30 500
1 200 1 120
7,6 –
12 100 10 500
18 500 16 600
0,837 0,837
71922 CE 71922 ACE
110
122,3 122,3
137,7 137,7
1,1 1,1
0,6 0,6
27,6 40,7
117 117
143 143
145 145
1 1
0,6 0,6
120
165 165
22 22
49 400 46 200
40 500 38 000
1 430 1 370
7,6 –
11 100 9 500
17 000 15 000
1,148 1,148
71924 CE 71924 ACE
120
133,9 133,9
151,1 151,1
1,1 1,1
0,6 0,6
30,3 44,7
127 127
158 158
160 160
1 1
0,6 0,6
160
161
Hybrid high-precision angular contact ball bearings d 8 – 17 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3 ra
ra
r1
2 da
Da
d d1
D D1
da Db
a CD, ACD, CX and ACX
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
8
22
7
3 450
1 460
68
8,4
80 000
120 000
0,01
708 CX/HC
8
11,8
17,6
0,3
0,1
6
10
20
20,1
0,3
0,1
9
24
7
3 710
1 730
80
8,8
80 000
120 000
0,01
709 CX/HC
9
13,5
19,9
0,3
0,1
6
11
22
22,1
0,3
0,1
10
22 22 26 26 30 30
6 6 8 8 9 9
2 600 2 510 5 070 4 940 5 920 5 720
1 250 1 200 2 400 2 280 2 700 2 600
57 55 110 106 156 150
9,5 – 8,3 – 8,2 –
80 000 75 000 75 000 70 000 70 000 67 000
120 000 110 000 110 000 100 000 100 000 95 000
0,008 0,008 0,016 0,016 0,025 0,025
71900 CX/HC 71900 ACX/HC 7000 CX/HC 7000 ACX/HC 7200 CX/HC 7200 ACX/HC
10
13,6 13,6 15,1 15,1 16,8 16,8
17,8 17,8 21,3 21 23,3 23,3
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
5 7 6 8 7 9
12 12 12 12 15 15
20 20 24 24 25 25
20,5 20,5 24,1 24,1 27,1 27,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
12
24 24 28 28 32 32
6 6 8 8 10 10
2 910 2 760 5 530 5 270 6 760 6 630
1 530 1 460 2 750 2 650 3 100 3 000
71 67 127 122 180 176
9,8 – 8,7 – 8,5 –
75 000 70 000 70 000 67 000 67 000 60 000
110 000 100 000 100 000 95 000 95 000 85 000
0,009 0,009 0,017 0,017 0,032 0,032
71901 CX/HC 71901 ACX/HC 7001 CX/HC 7001 ACX/HC 7201 CX/HC 7201 ACX/HC
12
15,9 15,9 17,1 17,1 18,2 18,2
20,1 20,1 23,3 23,3 25,8 25,8
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
5 7 7 9 8 10
14 14 14 14 17 17
22 22 26 26 27 27
22,5 22,5 26,1 26,1 29,1 29,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
15
28 28 32 32 35 35
7 7 9 9 11 11
4 360 4 160 6 240 5 920 7 410 7 150
2 400 2 280 3 450 3 250 3 650 3 550
110 104 160 153 212 204
9,6 – 9,3 – 8,5 –
67 000 63 000 63 000 56 000 60 000 53 000
95 000 90 000 90 000 80 000 85 000 75 000
0,013 0,013 0,025 0,025 0,037 0,037
71902 CX/HC 71902 ACX/HC 7002 CX/HC 7002 ACX/HC 7202 CX/HC 7202 ACX/HC
15
19,1 19,1 20,6 20,6 21,5 21,5
23,9 23,9 26,8 26,5 29,1 29,1
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
6 9 8 10 9 12
17 17 17 17 20 20
26 26 30 30 30 30
26,5 26,5 30,1 30,1 33 33
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
17
30 30 35 35 40 40
7 7 10 10 12 12
4 490 4 360 6 500 6 180 9 230 8 840
2 650 2 500 3 800 3 650 4 650 4 500
122 116 176 170 270 260
9,8 – 9,1 – 8,5 –
63 000 56 000 56 000 53 000 43 000 38 000
90 000 80 000 80 000 75 000 63 000 56 000
0,015 0,015 0,032 0,032 0,062 0,062
71903 CX/HC 71903 ACX/HC 7003 CX/HC 7003 ACX/HC 7203 CX/HC 7203 ACX/HC
17
21,1 21,1 22,9 22,9 24,2 24,2
25,9 25,9 29,6 29,2 32,8 32,8
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
7 9 9 11 10 13
19 19 19 19 22 22
28 28 33 33 35 35
28,5 28,5 33,4 33,4 38 38
0,3 0,3 0,3 0,3 0,6 0,6
0,1 0,1 0,1 0,1 0,3 0,3
162
163
Hybrid high-precision angular contact ball bearings d 20 – 40 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3 ra
ra
r1
2 da
Da
d d1
D D1
da Db
a CD, ACD, CX and ACX
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
20
37 37 42 42 47 47
9 9 12 12 14 14
6 630 6 240 10 400 9 950 12 400 11 900
4 050 3 900 6 100 5 850 6 550 6 200
186 180 280 270 375 360
9,8 – 9,2 – 8,7 –
53 000 48 000 48 000 43 000 43 000 40 000
75 000 67 000 67 000 60 000 60 000 56 000
0,031 0,031 0,058 0,058 0,089 0,089
71904 CX/HC 71904 ACX/HC 7004 CX/HC 7004 ACX/HC 7204 CX/HC 7204 ACX/HC
20
25,4 25,4 26,9 26,9 29,1 29,1
31,6 31,6 35,1 35,1 38,7 38,7
0,3 0,3 0,6 0,6 1 1
0,15 0,15 0,3 0,3 0,3 0,3
8 11 10 13 12 15
22 22 25 25 26 26
35 35 37 37 41 41
35,5 35,5 39,1 39,1 44,1 44,1
0,3 0,3 0,6 0,6 1 1
0,1 0,1 0,3 0,3 0,3 0,3
25
42 42 47 47 52 52
9 9 12 12 15 15
7 020 6 630 11 400 10 800 14 000 13 500
4 800 4 550 7 350 7 100 8 150 7 800
220 212 340 325 475 450
10 – 9,6 – 9,1 –
45 000 40 000 40 000 38 000 38 000 34 000
63 000 56 000 56 000 53 000 53 000 48 000
0,037 0,037 0,066 0,066 0,12 0,12
71905 CX/HC 71905 ACX/HC 7005 CX/HC 7005 ACX/HC 7205 CX/HC 7205 ACX/HC
25
30,4 30,4 31,9 31,9 34,1 34,1
36,6 36,6 40,1 40,1 43,7 43,7
0,3 0,3 0,6 0,6 1 1
0,15 0,15 0,3 0,3 0,3 0,3
9 12 11 15 13 17
27 27 30 30 31 31
40 40 42 42 46 46
40,5 40,5 44,1 44,1 49,1 49,1
0,3 0,3 0,6 0,6 1 1
0,1 0,1 0,3 0,3 0,3 0,3
30
47 47 55 55 62 62
9 9 13 13 16 16
7 150 6 760 14 600 14 000 24 200 23 400
5 200 4 900 10 000 9 650 16 000 15 300
240 228 465 440 670 640
10 – 9,4 – 14 –
38 000 34 000 34 000 32 000 32 000 28 000
53 000 48 000 48 000 45 000 45 000 40 000
0,043 0,043 0,094 0,094 0,17 0,17
71906 CX/HC 71906 ACX/HC 7006 CX/HC 7006 ACX/HC 7206 CD/HC 7206 ACD/HC
30
35,4 35,4 38,1 38,1 40,3 40,3
41,6 41,6 46,9 46,9 51,7 51,7
0,3 0,3 1 1 1 1
0,15 0,15 0,3 0,3 0,3 0,3
10 14 12 17 14 19
32 32 36 36 36 36
45 45 49 49 56 56
45,5 45,5 52,1 52,1 60 60
0,3 0,3 1 1 1 1
0,1 0,1 0,3 0,3 0,3 0,3
35
55 55 62 62 72 72
10 10 14 14 17 17
9 750 9 230 15 600 14 800 31 900 30 700
6 550 6 200 9 500 9 000 21 600 20 800
275 260 400 380 915 880
10 – 9,7 – 14 –
32 000 30 000 30 000 26 000 26 000 22 000
45 000 43 000 43 000 38 000 38 000 34 000
0,065 0,065 0,13 0,13 0,24 0,24
71907 CD/HC 71907 ACD/HC 7007 CD/HC 7007 ACD/HC 7207 CD/HC 7207 ACD/HC
35
41,2 41,2 43,7 43,7 47 47
48,8 48,8 53,3 53,3 60 60
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,3 0,3
11 16 14 19 16 21
40 40 41 41 42 42
50 50 56 56 65 65
53,8 53,8 60 60 70 70
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,3 0,3
40
62 62 68 68 80 80
12 12 15 15 18 18
12 400 11 700 16 800 15 900 41 000 39 000
8 500 8 000 11 000 10 400 28 000 27 000
360 340 465 440 1 180 1 140
10 – 10 – 14 –
28 000 24 000 26 000 22 000 22 000 20 000
40 000 36 000 38 000 34 000 34 000 32 000
0,096 0,096 0,16 0,16 0,3 0,3
71908 CD/HC 71908 ACD/HC 7008 CD/HC 7008 ACD/HC 7208 CD/HC 7208 ACD/HC
40
46,7 46,7 49,2 49,2 53 53
55,3 55,3 58,8 58,8 67 67
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
13 18 15 20 17 23
45 45 46 46 47 47
57 57 62 62 73 73
60,8 60,8 66 66 75 75
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
164
165
Hybrid high-precision angular contact ball bearings d 45 – 65 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3 ra
ra
r1
2 da
Da
d d1
D D1
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
45
68 68 75 75 85 85
12 12 16 16 19 19
13 000 12 400 28 600 27 600 42 300 41 000
9 500 9 000 22 400 21 600 31 000 30 000
400 380 950 900 1 320 1 250
11 – 15 – 14 –
24 000 22 000 22 000 20 000 20 000 18 000
36 000 34 000 34 000 32 000 32 000 28 000
0,11 0,11 0,2 0,2 0,34 0,34
71909 CD/HC 71909 ACD/HC 7009 CD/HC 7009 ACD/HC 7209 CD/HC 7209 ACD/HC
45
52,2 52,2 54,7 54,7 57,5 57,5
60,8 60,8 65,3 65,3 72,5 72,5
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
14 19 16 22 18 25
50 50 51 51 52 52
63 63 69 69 78 78
66,8 66,8 73 73 80 80
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
50
72 72 80 80 90 90
12 12 16 16 20 20
13 500 12 700 29 600 28 100 44 900 42 300
10 400 9 800 24 000 23 200 34 000 32 500
440 415 1020 980 1 430 1 390
11 – 15 – 15 –
22 000 19 000 20 000 18 000 19 000 17 000
34 000 30 000 32 000 28 000 30 000 26 000
0,11 0,11 0,21 0,21 0,38 0,38
71910 CD/HC 71910 ACD/HC 7010 CD/HC 7010 ACD/HC 7210 CD/HC 7210 ACD/HC
50
56,7 56,7 59,7 59,7 62,5 62,5
65,3 65,3 70,3 70,3 77,5 77,5
0,6 0,6 1 1 1,1 1,1
0,15 0,15 0,3 0,3 0,6 0,6
14 20 17 17 20 27
55 55 56 56 57 57
67 67 74 74 83 83
70,8 70,8 78 78 85 85
0,6 0,6 1 1 1 1
0,1 0,1 0,3 0,3 0,6 0,6
55
80 80 90 90 100 100
13 13 18 18 21 21
19 500 18 200 39 700 37 100 55 300 52 700
14 600 13 700 32 500 31 000 43 000 40 500
620 585 1 370 1 320 1 800 1 730
10 – 15 – 14 –
19 000 18 000 18 000 17 000 17 000 16 000
30 000 28 000 28 000 26 000 26 000 24 000
0,15 0,15 0,31 0,31 0,51 0,51
71911 CD/HC 71911 ACD/HC 7011 CD/HC 7011 ACD/HC 7211 CD/HC 7211 ACD/HC
55
62,7 62,7 66,3 66,3 69 69
72,3 72,3 78,7 78,7 85,9 85,9
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
16 22 19 26 21 29
61 61 62 62 64 64
74 74 83 83 91 91
78 78 86 86 95 95
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
60
85 85 95 95 110 110
13 13 18 18 22 22
19 900 18 600 40 300 39 000 67 600 63 700
15 300 14 600 34 500 33 500 53 000 50 000
655 620 1 500 1 400 2 240 2 120
11 – 15 – 14 –
18 000 17 000 17 000 16 000 16 000 15 000
28 000 26 000 26 000 24 000 24 000 22 000
0,16 0,16 0,34 0,34 0,65 0,65
71912 CD/HC 71912 ACD/HC 7012 CD/HC 7012 ACD/HC 7212 CD/HC 7212 ACD/HC
60
67,7 67,7 71,3 71,3 75,6 75,6
77,3 77,3 83,7 83,7 94,4 94,4
1 1 1,1 1,1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
16 23 20 27 23 31
66 66 67 67 69 69
79 79 88 88 101 101
83 83 91 91 105 105
1 1 1 1 1,5 1,5
0,3 0,3 0,6 0,6 0,6 0,6
65
90 90 100 100
13 13 18 18
20 800 19 500 41 600 39 000
17 000 16 000 37 500 35 500
710 680 1 600 1 500
11 – 16 –
17 000 16 000 16 000 15 000
26 000 24 000 24 000 22 000
0,17 0,17 0,36 0,36
71913 CD/HC 71913 ACD/HC 7013 CD/HC 7013 ACD/HC
65
72,7 72,7 76,3 76,3
82,3 82,3 88,7 88,7
1 1 1,1 1,1
0,3 0,3 0,6 0,6
17 25 20 28
71 71 72 72
84 84 93 93
88 88 96 96
1 1 1 1
0,3 0,3 0,6 0,6
166
167
Hybrid high-precision angular contact ball bearings d 70 – 100 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3 ra
ra
r1
2 da
Da
d d1
D D1
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
70
100 100 110 110
16 16 20 20
34 500 32 500 52 000 48 800
34 000 32 500 45 500 44 000
1 430 1 370 1 930 1 860
16 – 15 –
16 000 15 000 15 000 14 000
24 000 22 000 22 000 20 000
0,28 0,28 0,49 0,49
71914 CD/HC 71914 ACD/HC 7014 CD/HC 7014 ACD/HC
70
79,3 79,3 82,9 82,9
90,7 90,7 97,1 97,1
1 1 1,1 1,1
0,3 0,3 0,6 0,6
19 28 22 31
76 76 77 77
94 94 103 103
98 98 106 106
1 1 1 1
0,3 0,3 0,6 0,6
75
105 105 115 115
16 16 20 20
35 800 33 800 52 700 49 400
37 500 35 500 49 000 46 500
1 560 1 500 2 080 1 960
16 – 16 –
15 000 14 000 15 000 13 000
22 000 20 000 22 000 19 000
0,3 0,3 0,52 0,52
71915 CD/HC 71915 ACD/HC 7015 CD/HC 7015 ACD/HC
75
84,3 84,3 87,9 87,9
95,7 95,7 103 103
1 1 1,1 1,1
0,3 0,3 0,6 0,6
20 29 23 32
81 81 82 82
99 99 108 108
103 103 111 111
1 1 1 1
0,3 0,3 0,6 0,6
80
110 110 125 125
16 16 22 22
36 400 34 500 65 000 62 400
39 000 36 500 61 000 58 500
1 660 1 560 2 550 2 450
16 – 16 –
15 000 13 000 14 000 12 000
22 000 19 000 20 000 18 000
0,31 0,31 0,71 0,71
71916 CD/HC 71916 ACD/HC 7016 CD/HC 7016 ACD/HC
80
89,3 89,3 94,4 94,4
101 101 111 111
1 1 1,1 1,1
0,3 0,3 0,6 0,6
21 30 25 35
86 86 87 87
104 104 118 118
108 108 121 121
1 1 1 1
0,3 0,3 0,6 0,6
85
120 120 130 130
18 18 22 22
46 200 43 600 67 600 63 700
48 000 45 500 65 500 62 000
2 040 1 930 2 650 2 500
16 – 16 –
14 000 12 000 13 000 11 000
20 000 18 000 19 000 17 000
0,44 0,44 0,74 0,74
71917 CD/HC 71917 ACD/HC 7017 CD/HC 7017 ACD/HC
85
95,8 95,8 99,4 106
110 110 116 130
1,1 1,1 1,1 2
0,6 0,6 0,6 1
23 23 36 30
92 92 92 95
113 113 123 140
115 115 126 144
1 1 1 2
0,6 0,6 0,6 1
90
125 125 140 140
18 18 24 24
47 500 44 200 79 300 74 100
51 000 48 000 76 500 72 000
2 080 1 960 3 000 2 850
16 – 16 –
13 000 11 000 12 000 10 000
19 000 17 000 18 000 16 000
0,47 0,47 0,95 0,95
71918 CD/HC 71918 ACD/HC 7018 CD/HC 7018 ACD/HC
90
100 100 106 106
115 115 124 124
1,1 1,1 1,5 2
0,6 0,6 0,6 1
23 34 39 32
97 97 99 100
118 118 131 150
120 120 135 135
1 1 1,5 1,5
0,6 0,6 0,6 0,6
95
130 130 145 145
18 18 24 24
49 400 46 200 81 900 76 100
55 000 52 000 80 000 76 500
2 200 2 080 3 100 2 900
16 – 16 –
12 000 10 000 11 000 9 500
18 000 16 000 17 000 15 000
0,49 0,49 1 1
71919 CD/HC 71919 ACD/HC 7019 CD/HC 7019 ACD/HC
95
105 105 111 111
120 120 129 129
1,1 1,1 1,5 1,5
0,6 0,6 0,6 0,6
24 35 28 40
102 102 104 104
123 123 136 136
125 125 140 140
1 1 1,5 1,5
0,6 0,6 0,6 0,6
100
140 140 150 150
20 20 24 24
60 500 57 200 83 200 79 300
65 500 63 000 85 000 80 000
2 550 2 400 3 200 3 050
16 – 16 –
11 000 9 500 10 000 9 500
17 000 15 000 16 000 15 000
0,66 0,66 1,05 1,05
71920 CD/HC 71920 ACD/HC 7020 CD/HC 7020 ACD/HC
100
112 112 116 116
128 128 134 134
1,1 1,1 1,5 1,5
0,6 0,6 0,6 0,6
26 38 29 41
107 107 109 109
133 133 141 141
135 135 145 145
1 1 1,5 1,5
0,6 0,6 0,6 0,6
168
169
Hybrid high-precision angular contact ball bearings d 105 – 140 mm B r1 r1
r2
r4
r2
r2
ra
rb
r3 ra
ra
r1
2 da
Da
d d1
D D1
da Db
a CD, ACD
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
105
145 145
20 20
61 800 57 200
69 500 65 500
2 600 2 500
16 –
10 000 9 500
16 000 50 000
0,69 0,69
71921 CD/HC 71921 ACD/HC
105
117 117
133 133
1,1 1,1
0,6 0,6
27 39
112 112
138 138
140 140
1 1
0,6 0,6
110
150 150
20 20
62 400 58 500
72 000 68 000
2 700 2 550
17 –
10 000 9 000
16 000 14 000
0,72 0,72
71922 CD/HC 71922 ACD/HC
110
122 122
138 138
1,1 1,1
0,6 0,6
27 40
117 117
143 143
145 145
1 1
0,6 0,6
120
165 165
22 22
78 000 72 800
91 500 86 500
3 250 3 050
16 –
9 000 8 500
14 000 17 000
0,97 0,97
71924 CD/HC 71924 ACD/HC
120
133 133
152 152
1,1 1,1
0,6 0,6
30 44
127 127
158 158
160 160
1 1
0,6 0,6
130
180 180
24 24
92 300 87 100
108 000 102 000
3 650 3 450
16 –
8 500 8 000
13 000 12 000
1,3 1,3
71926 CD/HC 71926 ACD/HC
130
145 145
165 165
1,5 1,5
0,6 0,6
33 48
139 139
171 171
175 175
1,5 1,5
0,6 0,6
140
190 190
24 24
95 600 90 400
116 000 110 000
3 900 3 650
17 –
8 000 7 500
12 000 11 000
1,35 1,35
71928 CD/HC 71928 ACD/HC
140
155 155
175 175
1,5 1,5
0,6 0,6
34 51
149 149
181 181
185 185
1,5 1,5
0,6 0,6
170
171
Hybrid high speed high-precision angular contact ball bearings d 20 – 50 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
20
37 37 42 42
9 9 12 12
4 680 4 420 7 020 6 760
2 120 2 040 3 050 2 900
90 85 129 122
7 – 6,5 –
63 000 56 000 58 000 51 200
98 000 87 000 90 000 80 000
0,032 0,032 0,056 0,056
71904 CE/HC 71904 ACE/HC 7004 CE/HC 7004 ACE/HC
20
25,6 25,6 27,2 27,2
31,4 31,4 34,8 34,8
0,3 0,3 0,6 0,6
0,2 0,2 0,6 0,6
8,4 11,3 10,3 13,4
22 22 25 25
35 35 37 37
35,8 35,8 40,3 40,3
0,3 0,3 0,6 0,6
0,1 0,1 0,6 0,6
25
42 42 47 47
9 9 12 12
5 270 4 940 7 800 7 410
2 700 2 550 3 750 3 550
114 108 156 150
7,2 – 6,8 –
53 500 47 500 50 000 44 100
83 000 74 000 77 000 69 000
0,038 0,038 0,064 0,064
71905 CE/HC 71905 ACE/HC 7005 CE/HC 7005 ACE/HC
25
30,6 30,6 32,2 32,2
36,4 36,4 39,9 39,9
0,3 0,3 0,6 0,6
0,2 0,2 0,6 0,6
9,07 12,5 10,9 14,6
27 27 30 30
40 40 42 42
40,8 40,8 45,1 45,1
0,3 0,3 0,6 0,6
0,1 0,1 0,6 0,6
30
47 47 55 55
9 9 13 13
5 590 5 270 10 100 9 560
3 100 2 900 5 100 4 900
132 125 216 208
7,4 – 6,9 –
46 500 41 500 42 300 37 500
72 700 64 900 65 800 58 700
0,043 0,043 0,095 0,095
71906 CE/HC 71906 ACE/HC 7006 CE/HC 7006 ACE/HC
30
35,6 35,6 38,3 38,3
41,4 41,4 46,8 46,8
0,3 0,3 1 1
0,2 0,2 1 1
9,74 13,6 12,3 16,6
32 32 35 35
45 45 50 50
45,8 45,8 52,8 52,8
0,3 0,3 1 1
0,1 0,1 1 1
35
55 55 62 62
10 10 14 14
7 610 7 150 10 800 10 400
4 400 4 150 6 000 5 700
186 176 255 240
7,3 – 7,1 –
40 000 35 500 37 000 32 700
62 200 55 500 57 700 51 400
0,066 0,066 0,132 0,132
71907 CE/HC 71907 ACE/HC 7007 CE/HC 7007 ACE/HC
35
41,6 41,6 44,3 44,3
48,4 48,4 52,8 52,8
0,6 0,6 1 1
0,2 0,2 1 1
11,1 15,7 13,6 18,5
40 40 41 41
50 50 56 56
53,8 53,8 59,5 59,5
0,6 0,6 1 1
0,1 0,1 1 1
40
62 62 68 68
12 12 15 15
9 560 9 230 11 700 11 100
5 700 5 400 6 800 6 550
240 228 290 275
7,3 – 7,3 –
35 100 31 200 33 100 29 500
54 900 49 000 51 800 46 200
0,097 0,097 0,167 0,167
71908 CE/HC 71908 ACE/HC 7008 CE/HC 7008 ACE/HC
40
47,1 47,1 49,8 49,8
54,9 54,9 58,3 58,3
0,6 0,6 1 1
0,2 0,2 1 1
12,9 18,1 14,9 20,3
45 45 46 46
57 57 62 62
60,8 60,8 65,3 65,3
0,6 0,6 1 1
0,1 0,1 1 1
45
68 68 75 75
12 12 16 16
10 100 9 560 14 000 13 300
6 400 6 100 8 500 8 000
270 255 360 340
7,5 – 7,3 –
31 500 28 200 30 000 26 500
49 500 44 200 46 600 41 600
0,116 0,116 0,208 0,208
71909 CE/HC 71909 ACE/HC 7009 CE/HC 7009 ACE/HC
45
52,6 52,6 55,3 55,3
60,4 60,4 64,8 64,8
0,6 0,6 1 1
0,2 0,2 1 1
13,7 19,4 16,2 22,2
50 50 51 51
63 63 69 69
66,8 66,8 72 72
0,6 0,6 1 1
0,1 0,1 1 1
50
72 72 80 80
12 12 16 16
10 600 9 950 14 800 14 000
7 100 6 700 9 500 9 000
300 285 400 380
7,6 – 7,4 –
29 500 26 200 27 500 24 500
45 900 40 000 43 000 38 000
0,116 0,116 0,226 0,226
71910 CE/HC 71910 ACE/HC 7010 CE/HC 7010 ACE/HC
50
57,1 57,1 60,3 60,3
64,9 64,9 69,8 69,8
0,6 0,6 1 1
0,2 0,2 1 1
14,3 20,4 16,9 23,4
55 55 55 55
67 67 74 74
70,8 70,8 76,8 76,8
0,6 0,6 1 1
0,1 0,1 1 1
172
173
Hybrid high speed high-precision angular contact ball bearings d 55 – 85 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
55
80 80 90 90
13 13 18 18
15 300 14 600 15 600 14 800
10 000 9 500 10 600 10 000
425 400 450 425
7,5 – 7,5 –
26 500 23 500 24 700 22 000
41 000 37 000 38 000 34 000
0,149 0,149 0,36 0,36
71911 CE/HC 71911 ACE/HC 7011 CE/HC 7011 ACE/HC
55
62,7 62,7 67,8 67,7
72,3 72,3 77,3 77,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
15,7 22,5 18,9 26,2
61 61 62 62
74 74 82 82
78 78 86,4 86,4
1 1 1 1
0,3 0,3 1 1
60
85 85 95 95
13 13 18 18
15 600 14 800 16 300 15 300
10 600 10 000 11 600 11 000
450 425 490 465
7,5 – 7,6 –
24 600 22 000 23 000 20 500
38 000 34 000 36 000 32 000
0,159 0,159 0,385 0,385
71912 CE/HC 71912 ACE/HC 7012 CE/HC 7012 ACE/HC
60
67,7 67,7 72,8 72,8
77,3 77,3 82,3 82,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
16,4 23,7 19,5 27,3
66 66 67 67
79 79 88 88
83 83 91 91
1 1 1 1
0,3 0,3 1 1
65
90 90 100 100
13 13 18 18
16 300 15 300 16 800 15 900
11 600 11 000 12 700 12 000
490 465 540 510
7,6 – 7,7 –
23 100 20 500 21 700 19 100
36 000 32 000 33 000 30 000
0,17 0,17 0,411 0,411
71913 CE/HC 71913 ACE/HC 7013 CE/HC 7013 ACE/HC
65
72,7 72,7 77,8 77,8
82,3 82,3 87,3 87,3
1 1 1,1 1,1
0,3 0,3 1,1 1,1
17 24,8 20,2 28,5
71 71 72 72
84 84 93 93
88 88 96 96
1 1 1 1
0,3 0,3 1 1
70
100 100 110 110
16 16 20 20
21 600 20 300 22 500 21 600
15 000 14 300 16 600 15 600
640 600 695 670
7,5 – 7,5 –
21 100 18 600 20 000 17 500
32 000 29 000 31 000 27 000
0,276 0,276 0,555 0,555
71914 CE/HC 71914 ACE/HC 7014 CE/HC 7014 ACE/HC
70
79,2 79,2 84,3 84,3
90,8 90,8 95,8 95,8
1 1 1,1 1,1
0,3 0,3 1,1 1,1
19,6 28,1 22,2 31,3
76 76 77 77
94 94 103 103
98 98 106 106
1 1 1 1
0,3 0,3 1 1
75
105 105 115 115
16 16 20 20
22 500 21 600 22 900 21 600
16 600 15 600 17 300 16 300
695 670 735 695
7,5 – 7,6 –
20 000 17 500 18 600 16 600
31 000 27 000 29 000 26 000
0,294 0,294 0,586 0,586
71915 CE/HC 71915 ACE/HC 7015 CE/HC 7015 ACE/HC
75
84,2 84,2 89,3 89,3
95,8 95,8 100,8 100,8
1 1 1,1 1,1
0,3 0,3 1,1 1,1
20,2 29,3 22,9 32,5
81 81 82 82
99 99 108 108
103 103 111 111
1 1 1 1
0,3 0,3 1 1
80
110 110 125 125
16 16 22 22
22 900 21 600 29 100 27 600
17 300 16 300 21 600 20 400
735 695 900 850
7,6 – 7,5 –
18 800 16 600 17 500 15 500
29 000 26 000 27 000 24 000
0,309 0,309 0,768 0,768
71916 CE/HC 71916 ACE/HC 7016 CE/HC 7016 ACE/HC
80
89,2 89,2 95,9 95,9
100,8 100,8 109,2 109,2
1 1 1,1 1,1
0,3 0,3 1,1 1,1
20,9 30,5 24,9 35,2
86 86 87 87
104 104 118 118
108 108 121 121
1 1 1 1
0,3 0,3 1 1
85
120 120 130 130
18 18 22 22
29 100 27 600 29 600 28 100
21 600 20 400 22 800 21 600
900 850 930 880
7,5 – 7,6 –
17 500 15 500 16 500 14 600
27 000 24 000 26 000 23 000
0,438 0,438 0,805 0,805
71917 CE/HC 71917 ACE/HC 7017 CE/HC 7017 ACE/HC
85
95,8 95,8 100,9 100,9
109,2 109,2 114,2 114,2
1,1 1,1 1,1 1,1
0,6 0,6 1,1 1,1
22,9 33,2 25,6 36,4
92 92 92 92
113 113 123 123
115 115 126 126
1 1 1 1
0,6 0,6 1 1
174
175
Hybrid high speed high-precision angular contact ball bearings d 90 – 120 mm B r1 r3
r2
r4
r4
r2
rb
ra r3
Da d b
d d1
D D1
ra
ra
r1
da
da Db
2
Db
a CE, ACE
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Calculation factor
Speed ratings Lubrication grease oil spot
N
–
r/min
Mass
Designation
f0
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
D1 ≈
r1, 2 min
r3, 4 min
a
da min
Da max
Db max
ra max
rb max
mm
90
125 125 140 140
18 18 24 24
29 600 28 100 37 100 35 100
22 800 21 600 28 000 26 500
930 880 1 100 1 040
7,6 – 7,5 –
16 500 15 600 15 500 13 800
26 000 23 000 24 000 21 000
0,459 0,459 1,028 1,028
71918 CE/HC 71918 ACE/HC 7018 CE/HC 7018 ACE/HC
90
100,8 100,8 107,4 107,4
114,2 114,2 122,7 122,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
23,6 34,4 27,6 39,2
97 97 99 99
118 118 131 131
120 120 135 135
1 1 1,5 1,5
0,6 0,6 1,5 1,5
95
130 130 145 145
18 18 24 24
31 200 29 600 37 700 35 800
24 500 23 200 29 000 28 000
980 930 1 140 1 080
7,6 – 7,5 –
16 000 14 200 15 000 13 100
24 000 22 000 23 000 20 000
0,482 0,482 1,074 1,074
71919 CE/HC 71919 ACE/HC 7019 CE/HC 7019 ACE/HC
95
105,8 105,8 112,4 112,4
119,2 119,2 127,7 127,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
24,3 35,6 28,3 40,4
102 102 104 104
123 123 136 136
125 125 140 140
1 1 1,5 1,5
0,6 0,6 1,5 1,5
100
140 140 150 150
20 20 24 24
37 700 35 800 39 000 36 400
29 000 28 000 30 500 29 000
1 140 1 080 1 160 1 100
7,5 – 7,6 –
15 000 13 300 14 400 12 600
23 000 20 000 22 000 19 000
0,651 0,651 1,119 1,119
71920 CE/HC 71920 ACE/HC 7020 CE/HC 7020 ACE/HC
100
112,3 112,3 117,4 117,4
127,7 127,7 132,7 132,7
1,1 1,1 1,5 1,5
0,6 0,6 1,5 1,5
26,3 38,4 29 41,5
107 107 109 109
133 133 141 141
135 135 145 145
1 1 1,5 1,5
0,6 0,6 1,5 1,5
105
145 145
20 20
39 000 36 400
30 500 29 000
1 160 1 100
7,6 –
14 400 12 800
22 000 20 000
0,678 0,678
71921 CE/HC 71921 ACE/HC
105
117,3 117,3
132,7 132,7
1,1 1,1
0,6 0,6
27 39,5
112 112
138 138
140 140
1 1
0,6 0,6
110
150 150
20 20
39 700 37 100
32 000 30 500
1 200 1 120
7,6 –
13 700 12 100
21 000 19 000
0,705 0,705
71922 CE/HC 71922 ACE/HC
110
122,3 122,3
137,7 137,7
1,1 1,1
0,6 0,6
27,6 40,7
117 117
143 143
145 145
1 1
0,6 0,6
120
165 165
22 22
49 400 46 200
40 500 38 000
1 430 1 370
7,6 –
12 500 11 200
19 000 17 000
0,96 0,96
71924 CE/HC 71924 ACE/HC
120
133,9 133,9
151,1 151,1
1,1 1,1
0,6 0,6
30,3 44,7
127 127
158 158
160 160
1 1
0,6 0,6
176
177
Cylindrical roller bearings Contents
Cylindrical roller bearings Three different designs Double row cylindrical roller bearings Single row cylindrical roller bearings Hybrid cylindrical roller bearings General bearing data Radial internal clearance Preload Equivalent dynamic bearing load Equivalent static bearing load Designation of high-precision cylindrical roller bearings Supplementary designations – specific suffixes Product tables High-precision double row cylindrical roller bearings High-precision single row cylindrical roller bearings Hybrid high-precision single row cylindrical roller bearings
180 180 181 182 183 184 188 189 192 192 193 193 195 196 204 208
179
3
3 Cylindrical roller bearings
Cylindrical roller bearings Three different designs SKF high-precision cylindrical roller bearings are available in three different designs: two double row series NN 30 and NNU 49 and a high-speed design, single row cylindrical roller bearing series N 10. NNU 49 series offer especially compact dimensions and may be preferred when
limited room is available. The NN 30 series offers an optimum compromise between achievable speed and high rigidity and represents one of the more popular choices, particularly for the spindles rearside support. Whenever demand for rotational speed exceeds the standard series capability, then the single row series N 10 may be the solution.
Double row cylindrical roller bearings SKF high-precision double row cylindrical roller bearings are available in two different designs: NN (➔ fig 1 ) and NNU (➔ fig 2 ) designs, and two series: Dimension Series 30 and 49 (➔ fig 3 ). The rollers of NN design bearings are guided between integral flanges on the inner ring, while rollers of NNU design bearings are guided between integral flanges on the outer ring. The other ring has no flanges. This means that a certain amount of axial displacement of the shaft with respect to the housing in both directions can be accommodated within the bearing (see dimension ‘s’ in the product tables). These bearings are also separable, and the bearing ring with integral flanges, together with the roller and cage assembly, can be withdrawn from the flangeless ring. This facilitates mounting and dismounting.
Double row highprecision cylindrical roller bearing, NNU design
Double row highprecision cylindrical roller bearing, NN design Fig
1
Fig
The NN design bearings listed in this catalogue follow ISO Dimension Series 30, whereas the NNU design bearings follow ISO Dimension Series 49. Bearings of series NNU 49 with their very low crosssection, permit stiffer bearing arrangements than those of series NN 30, but are not able to carry such heavy loads as the NN 30 series bearings. SKF double row cylindrical roller bearings are available with either cylindrical bore or tapered bore (with a taper 1:12). In the machine tool industry, cylindrical roller bearings are generally supplied with a tapered bore, as this design allows a certain radial internal clearance or preload to be achieved by adjustment, when mounting bearings on a tapered shaft. In order to facilitate efficient lubrication, bearings of series NNU 49, that have very low cross section, have an annular groove and three lubrication holes in the outer ring as standard (W33 designation). Oil spot pipes can be either inserted in the holes in
A cross section of the two dimension series 2
Fig
NNU 49
180
NN 30
3
N 10
181
3
3 Cylindrical roller bearings the annular groove, or positioned at the side of the bearings at a height specified in the table shown in the lubrication section of this publication. Bearings of series NN 30, that are mostly used in the machine tool spindles, are manufactured without this feature as the oil is commonly injected through pipes positioned at the side of the bearing. For special applications where bearings of the NN 30 series with the annular groove and the three lubrication holes in the outer ring are necessary, please contact the SKF applications engineering service. In cases where demand for running accuracy is exceptionally high, it is possible to mount the flangeless ring of bearings of series NNU 49, on to the shaft and to finish-grind the raceway and other seating surfaces of the shaft. For such applications, SKF can supply bearings of series NNU 49 having a tapered bore fitted with inner rings with pre-ground raceways. Such bearings are identified by the designation suffix VU001 (➔ Table 1 ).
Table Bearing bore diameter over incl.
Grinding allowance
mm
mm
– 110 360
182
110 360 –
1
Single row cylindrical roller bearings
Hybrid cylindrical roller bearings
The single row bearings series N 10 (➔ fig 4 ) have the same section height as the double row bearings of series NN 30 and follow ISO Dimension Series 10. The rollers of series N 10 bearings are guided between two integral flanges on the inner ring; the outer ring is without flanges. It is therefore possible for a certain amount of axial displacement of the shaft with respect to the housing to be accommodated within the bearing (see bearing tables).They are available with a tapered bore only (taper 1:12) and as with double row bearings, single row bearings are separable, i.e. the inner ring with roller and cage assembly can be withdrawn from the flangeless outer ring. High-precision single row cylindrical roller bearings are designed for bearing arrangements with different requirements from those for double row cylindrical roller bearings. Instead of very high load carrying capacity, single row cylindrical roller bearings are used where increased speed capability and more compact spindle design are needed.
SKF high-precision cylindrical roller bearings series NN 30 and N 10 can be delivered with ceramic rollers when the performances required cannot be met by all-steel bearings. As mentioned for hybrid high-precision angular contact ball bearings, hybrid cylindrical roller bearings can run faster, with lower temperature rise and enhance the system rigidity, without mentioning that they minimise lubrication and vibrations, and are less sensible to accelerations and decelerations. In order to exploit the best possibilities in terms
Fig
4
of speed, the use of ceramic rollers is normally matched with that of a one-piece outer ring land riding PEEK cage. High-precision single row cylindrical roller bearings with a PEEK cage and ceramic rollers can reach a reference speed of 2 million n × dm when lightly loaded and oil-air lubricated, and of 1,4 million n × dm when grease lubricated. As an option to further improve lubricant flow, bearings of series N 10 with special holes in the outer ring may be ordered. Hybrid cylindrical roller bearings are identified by the suffix HC5 in the bearing designation.
Single row high-precision cylindrical roller bearing
0,2 0,3 0,4
183
3
3 Cylindrical roller bearings
General bearing data
needed for machine tool applications. Tolerance class SP specifies dimensional accuracy which corresponds approximately to tolerance class P5 and running accuracy to P4. For special applications where extreme precision is required, tolerance class UP (ultra precision) can be supplied to order. Tolerance class UP specifies dimensional accuracy which corresponds approximately to tolerance class P4 and running accuracy better than P4. The values for class SP and UP tolerances are given in Tables 3 , 4 page 186 and 5 page 187.
Dimensions The boundary dimensions of the double row bearings shown in the tables conform to ISO 15:1998, Dimension Series 49 and 30. Single row bearings conform to ISO Dimension Series 10. Tolerances SKF high-precision cylindrical roller bearings are produced as standard to the tolerance class SP (special precision) specifications
Table Chamfer dimension, r2 min
Bearing bore diameter d over
(1)
mm
mm
0,6 1 1,1
– – – 120 – 120 – 80 220 – 280 – 280 – –
1,5 2
2,1 2,5 3 4
1)
2
Measuring distance a incl. mm – – 120 – 120 – 80 220 – 280 – 280 – – –
2,5 3,5 4 5 5 6 5,5 6 7 7,5 8,5 7,5 8,5 9,5 11
3
r2 min values are given in the product tables (➔ pages 195 – 211)
Angle deviation – measuring distance a
Measuring of angle deviation Tapered bore Half angle of taper α = 2° 23′ 9,4″
1 Largest theoretical taper d1 = d + 12 B
Tolerances for tapered bore, taper 1:12 Fig
Table
5 Tolerance class SP
B d over
B
incl.
mm
a
m
d1 d3
a d2
d2+∆a2mp d+amp
d d3+c3mp
α
α
18 30 50 80 120 180 250
∆ d2mp high
low
µm
30 50 80 120 180 250 315
+10 +12 +15 +20 +25 +30 +35
0 0 0 0 0 0 0
3
Tolerance class UP
Vdp max
∆d3mp-∆ d2mp high low
∆ d2mp high
µm
µm
µm
3 4 5 5 7 8 9
+4 +4 +4 +7 +7 +8 +10
1)
+1 +1 +1 +2 +2 +2 +2
+6 +8 +9 +10 +13 +15 +18
low
0 0 0 0 0 0 0
Vdp max
∆ d3mp-∆ d2mp1) high low
µm
µm
2 3 3 4 5 7 9
+3 +3 +3 +4 +4 +5 +5
+1 +1 +1 +1 +1 +1 +1
a2mp–a2mp 2
184
m
1)
Angular deviation over measuring length m (➔ fig 5 and Table 2 )
185
3 Cylindrical roller bearings Table Inner ring d over
incl.
∆ds high
low
µm
18 30 50 80 120 180 250 315
0 0 0 0 0 0 0 0
–5 –6 –8 –9 –10 –13 –15 –18
Vdp max
∆Bs high
µm
µm
3 3 4 5 5 7 8 9
0 0 0 0 0 0 0 0
low
–100 –100 –120 –150 –200 –250 –300 –350
VBs max
Kia max
Sd max
d over
µm
µm
µm
mm
5 5 5 6 7 8 10 13
3 3 4 4 5 6 8 8
8 8 8 8 9 10 11 13
– 18 30 50 80 120 180 250
Outer ring D over
incl.
∆Ds high
low
µm
50 80 120 150 180 250 315 400 500
0 0 0 0 0 0 0 0 0
–7 –9 –10 –11 –13 –15 –18 –20 –23
Class SP tolerances for radial bearings
186
5
incl.
∆ds high
low
µm
Vdp max
∆Bs high
µm
µm
low
VBs max
Kia max
Sd max
µm
µm
µm
18 30 50 80 120 180 250 315
0 0 0 0 0 0 0 0
–4 –5 –6 –7 –8 –10 –12 –18
2 3 3 4 4 5 6 9
0 0 0 0 0 0 0 0
–25 –25 –30 –40 –50 –60 –75 –90
1,5 1,5 2 3 3 4 5 6
1,5 1,5 2 2 3 3 4 5
2 3 3 4 4 5 6 6
incl.
∆Ds high
low
VDp max
∆Cs high
low
VCs max
Kea max
SD max
µm
µm
µm
µm
µm
3 3 4 4 5 5 6 7 12
Values are identical to those for inner ring of same bearing
2 3 3 4 4 5 6 8 10
3 3 3 4 4 5 6 7 8
2 2 3 3 3 4 4 5 –
3
Outer ring
mm
30 50 80 120 150 180 250 315 400
Table Inner ring
mm
– 18 30 50 80 120 180 250
4
VDp max
∆Cs high
µm
4 5 5 6 7 8 9 10 12
VCs max
Kea max
SD max
D over
µm
µm
µm
µm
mm
Values are identical to those for inner ring of same bearing
5 6 7 7 8 10 13 15 25
5 5 6 7 8 10 11 13 15
8 8 9 10 10 11 13 13 15
30 50 80 120 150 180 250 315 400
low
µm
50 80 120 150 180 250 315 400 500
0 0 0 0 0 0 0 0 0
–5 –6 –7 –8 –9 –10 –12 –14 –23
Class UP tolerances for radial bearings
187
3 Cylindrical roller bearings
Radial internal clearance
request, with reduced radial clearance (smaller than C1) for enhanced precision after mounting. Please consult the SKF application engineering service for more details. Both series NNU 49 and NN 30 bearings may be supplied with larger radial internal clearance for certain applications, as required. When ordering, the desired clearance should be indicated in the designation using the suffixes SP or UP, followed by the suffix for the requested clearance, C2, CN (for Normal radial clearance) or C3, for example NN 3026 K/SPC2. Cylindrical roller bearing clearance values are given in Table 6 . They are valid for unmounted bearings under zero measuring load.
High-precision cylindrical roller bearings actual clearance limits are in accordance with ISO 5753:1991. Cylindrical roller bearings for precision applications are supplied with C1 radial internal clearance class as standard, although this is not apparent from the bearing designation. The bearing rings of individual bearings must be kept together as supplied, otherwise the bearing clearance may become too great or too small, thus influencing the assembly procedures. The bearings are usually supplied packed in a single box, however, if the rings are packed separately, the rings of each bearing are identified by the same serial number. Bearings of the N 10 and NN 30 series can also be supplied on
Preload To ensure maximum running accuracy and rigidity, high-precision cylindrical roller bearings should have, after mounting, a minimum radial internal clearance or a preload. Generally, cylindrical roller bearings with tapered bore are mounted with preload. The magnitude of the operational clearance or preload depends on the speed, load, lubrication and required stiffness. It is also dependent on the accuracy of form of the bearing seating. Temperature conditions in the bearing should also be taken into consideration, since a reduction in clearance or an increase in preload may result. The following table gives guidelines on preloading cylindrical roller bearings series NN 30 K and N 10 K for machine tool applications. For special cases, please consult SKF. Speed − n dm value
Table Bore diameter
Radial internal clearance Bearings with cylindrical bore
d over
C1 min
incl.
mm
max
µm
SPC2 min
max
µm
Bearings with tapered bore Normal min max
C3 min
µm
µm
max
C1 min
max
µm
SPC2 min
max
µm
24 30 40 50 65 80 100
30 40 50 65 80 100 120
5 5 5 5 10 10 10
15 15 18 20 25 30 30
10 12 15 15 20 25 25
25 25 30 35 40 45 50
20 25 30 40 40 50 50
45 50 60 70 75 85 90
35 45 50 60 65 75 85
60 70 80 90 100 110 125
15 15 17 20 25 35 40
25 25 30 35 40 55 60
25 25 30 35 40 45 50
35 40 45 50 60 70 80
120 140 160 180 200 225 250
140 160 180 200 225 250 280
10 10 10 15 15 15 20
35 35 40 45 50 50 55
30 35 35 40 45 50 55
60 65 75 80 90 100 110
60 70 75 90 105 110 125
105 120 125 145 165 175 195
100 115 120 140 160 170 190
145 165 170 195 220 235 260
45 50 55 60 60 65 75
70 75 85 90 95 100 110
60 65 75 80 90 100 110
90 100 110 120 135 150 165
188
6
500 000 > 500 000 < 1 000 000 > 1 000 000
Preload/clearance (microns) 2 – 5, preload 1 – 2, preload 0 – 4, clearance
Preloading bearings The adjustment of clearance, or preload for double and single row cylindrical roller bearings with tapered bore, is achieved by driving up the bearing on its tapered seating. The SKF gauges shown on pages 286 – 295 enable the internal clearance, or preload to be set very accurately, quickly and reliably. The use of a gauge is particularly advantageous where series mounting is concerned, as it is then not possible to determine and measure the axial displacement of the inner ring.
If SKF gauges are not available, the axial displacement of the inner ring on its tapered seating must be determined, in accordance with the required clearance or preload. In order to do this the outer ring should be mounted in the housing, the inner ring then pushed on the seating and the residual clearance measured. Knowing the residual radial clearance, the axial displacement i.e. the additional distance through which the bearing must be pushed up on its tapered seating can be obtained from: B = L − ec/1 000 where B = width of spacer, mm L = measured distance between inner ring side face and abutment, mm c = measured clearance plus required preload (or minus required clearance), µm e = factor depending on the ratio of the internal diameter (di) and the outside diameter (d) of the hollow spindle fig 6 page 190, see table below. Diameter Ratio di/d
Factor e Bearing series NN 30 K & N10 K
0,2 0,3 0,4 0,5 0,6 0,7
12,5 14,5 15 16 17 18
NNU 49 BK 12 13 14 15 16 17
189
3
3 Cylindrical roller bearings If a threaded nut is used for driving up the inner ring assembly on the tapered seating, the angle through which the nut should be turned for a given clearance reduction of the bearing can be calculated from the equation: γ = 360 e ∆/(1 000 s) where γ = angle of turn of the nut, degrees e = factor depending on shaft diameters ∆ = clearance reduction in bearing, µm s = thread lead, mm A detailed description of the mounting procedure for high-precision cylindrical roller bearings is given in the Mounting Chapter (➔ pages 79 – 109). Cages SKF double row cylindrical roller bearings are fitted as standard with a single piece machined brass cage, or with two separate pronged cages with cover, made of polyamide. Single row bearings of the series
N 10 K incorporate the same pronged polyamide cages as the corresponding NN 30 K series bearings. Bearings with polyamide cages, NN 3008 to NN 3026 and N 1008 K to N 1024 K (identified by designation suffix TN or TN9), may be used without restriction at the temperatures normally encountered in machine tool operation, up to a maximum of 120°C. For high-speed applications a ‘one piece’ design outer ring land-riding cage made of light weight glass fibre reinforced polyether-ether-ketone (PEEK) is available. This cage is identified by the suffix TNHA in the designation. The lubricants generally used for rolling bearings have no detrimental effect on cage properties, with the exception of some synthetic oils and greases based on synthetic oils. If lubricants containing a high proportion of EP additives are used, especially at elevated temperatures, this may affect cage performance. For more details, please consult the SKF application engineering service.
Speed ratings The speed ratings quoted in the product tables are guideline values that are valid provided the bearings have a maximum preload in operation of 2 µm, and that adjacent components are made with the accuracy prescribed on pages 48 – 50. Where heavier preloads occur, or where the adjacent components are less accurate, the speed ratings must be reduced. Design of associated components If bearings of series NN 30 (K) and series N 10 K fitted with a polyamide cage (sizes 08 to 26 inclusive; designation suffix TN or TN9) are to permit axial displacement of the shaft with respect to the housing, to be taken up in the bearing, space must be provided at the sides of the bearing as shown in fig 7 . This prevents damage, such as the cage fouling the face of an adjacent component. The minimum width of this free space should be Ca = 1,3 s
where Ca = minimum width of free space, mm; s = permissible axial displacement from the normal position of one bearing ring in relation to the other, mm (see product tables). To facilitate mounting and dismounting of bearings with tapered bore of larger sizes (from bore diameters of approximately 80 mm), it is advisable to use the SKF oil injection method, where oil under high pressure is injected between the bearing bore and its seating. This considerably reduces the force needed to mount or dismount the bearing and practically eliminates the risk of damaging the bearing or the spindle. Where bearings with cylindrical bore are concerned, the oil injection method is used only for dismounting. In order to use the oil injection method it is necessary to provide shafts and/or housings with ducts and distribution grooves. Details of the recommended dimensions and thread for the oil supply connection are provided on request.
Permissible axial displacement from the normal position of one bearing ring in relation to the other
Spindle wall thickness Fig
6
Fig
Ca
Shaft tapered seating
7
Ca S
di
d
Shaft axis
190
191
3
3 Cylindrical roller bearings
Equivalent dynamic bearing load
Equivalent static bearing load
For cylindrical roller bearings which can only accommodate radial load
For the same reason mentioned before:
P = Fr
192
P 0 = Fr
Designation of high-precision Supplementary designations – specific suffixes cylindrical roller bearings The complete designation of a high-precision cylindrical roller bearing identifies the series, bore diameter, bore shape, cage type and design, as well as the suffix indicating the tolerance class e.g. NN 3014 KTN/SP. Additional digits may be added to identify bearings incorporating special features, such as: special clearance, special tolerances, etc. Please consult SKF for precise information. The designation scheme of SKF highprecision cylindrical roller bearings is shown in Table 7 page 194.
Cylindrical roller bearings are available with information about the exact outside diameter. This information is marked on the box as well as on an inspection sheet inside the box. Bearings supplied with this information and also with the actual clearance specified have the additional suffix VR521, VR522 or VQ496 (also including smaller clearance than standard).
193
3
3 Cylindrical roller bearings Table
NN 30 20
K TN9 / HC5 SP W33 VR521
7
Product tables
Bearing series NNU 49 Double row cylindrical roller bearing, ISO dimension series 49, flanges of the outer ring NN 30 Double row cylindrical roller bearing, ISO dimension series 30, flanges of the inner ring N 10 Single row cylindrical roller bearing, ISO dimension series 10, flanges of the inner ring
3
Bore diameter 05 (×5) 25 mm bore diameter I 48 (×5) 240 mm bore diameter Internal design B Internal design code (NNU 49 series only) Bore shape – Cylindrical bore (NNU 49 and NN 30 series only) K Tapered bore 1:12 Cage design and material – Rolling elements riding, brass TNHA Outer ring land-riding, glass fibre reinforced PEEK TN Rolling elements riding, Polyamide 6,6 TN9 Rolling elements riding, grass fibre reinforces Polyamide 6,6 Rolling element material – Chromium steel HC5 Silicon nitride Precision class SP Special precision (P4 running accuracy) UP Ultra precision (running accuracy better than P4) Lubrication W33 Groove and lubrication holes in the outer ring (on request for NN 30 series) Other V numbers Further specific information about the bearing
Designations of high-precision cylindrical roller bearings
194
195
High-precision double row cylindrical roller bearings d 25 – 80 mm s
s
b K
B r1
D1
d
F
r2
ra
Da
da
d
d d1
ra
ra
ra
r2
D E
ra
ra
r1
Da
da
Da da
db
db
Da da
3 NNU 49 B/W33
Principal dimensions d
D
NNU 49 BK/W33
Basic load ratings dynamic static B
mm
C
C0
N
NN 30
NN 30 KTN
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1, D1 ≈
Abutment and fillet dimensions
E, F
b
K
r1, 2 min
s
da min
da max
db min
Da max
Da min
ra max
mm
25
47
16
26 000
30 000
3 100
19 000
22 000
0,12
NN 3005 K
25
33,3
41,3
–
–
0,6
1,4
29
–
–
43
42
0,6
30
55 55
19 19
30 800 30 800
37 500 37 500
3 900 3 900
16 000 16 000
18 000 18 000
0,19 0,19
NN 3006 TN NN 3006 KTN
30
39,7 39,7
48,5 48,5
– –
– –
1 1
1,8 1,8
35 35
– –
– –
50 50
49 49
1 1
35
62 62
20 20
39 100 39 100
50 000 50 000
5 400 5 400
14 000 14 000
16 000 16 000
0,25 0,25
NN 3007 NN 3007 K
35
45,4 45,4
55 55
– –
– –
1 1
1,8 1,8
40 40
– –
– –
57 57
56 56
1 1
40
68 68
21 21
42 900 42 900
56 000 56 000
6 480 6 480
12 000 12 000
14 000 14 000
0,3 0,3
NN 3008 TN NN 3008 KTN
40
50,6 50,6
61 61
– –
– –
1 1
1,3 1,3
45 45
– –
– –
63 63
62 62
1 1
45
75 75
23 23
50 100 50 100
65 500 65 500
7 650 7 650
11 000 11 000
13 000 13 000
0,38 0,38
NN 3009 TN NN 3009 KTN
45
56,3 56,3
67,5 67,5
– –
– –
1 1
2 2
50 50
– –
– –
70 70
69 69
1 1
50
80 80
23 23
52 800 52 800
73 500 73 500
8 500 8 500
10 000 10 000
12 000 12 000
0,42 0,42
NN 3010 TN NN 3010 KTN
50
61,3 61,3
72,5 72,5
– –
– –
1 1
2 2
55 55
– –
– –
75 75
74 74
1 1
55
90 90
26 26
69 300 69 300
96 500 96 500
11 600 11 600
9 500 9 500
11 000 11 000
0,62 0,62
NN 3011 TN NN 3011 KTN
55
68,2 68,2
81 81
– –
– –
1,1 1,1
2 2
61,5 61,5
– –
– –
83,5 83,5
82 82
1 1
60
95 95
26 26
73 700 73 700
106 000 106 000
12 700 12 700
9 000 9 000
10 000 10 000
0,66 0,66
NN 3012 TN NN 3012 KTN
60
73,3 73,3
86,1 86,1
– –
– –
1,1 1,1
2 2
66,5 66,5
– –
– –
88,5 88,5
87 87
1 1
65
100 100
26 26
76 500 76 500
116 000 116 000
13 700 13 700
8 500 8 500
9 500 9 500
0,71 0,71
NN 3013 TN NN 3013 KTN
65
78,2 78,2
91 91
– –
– –
1,1 1,1
2 2
71,5 71,5
– –
– –
93,5 93,5
92 92
1 1
70
110 110
30 30
96 800 96 800
150 000 150 000
17 300 17 300
7 500 7 500
8 500 8 500
1 1
NN 3014 TN NN 3014 KTN
70
85,6 85,6
100 100
– –
– –
1,1 1,1
2,5 2,5
76,5 76,5
– –
– –
103,5 103,5
101 101
1 1
75
115 115
30 30
96 800 96 800
150 000 150 000
17 600 17 600
7 000 7 000
8 000 8 000
1,1 1,1
NN 3015 TN NN 3015 KTN
75
90,6 90,6
105 105
– –
– –
1,1 1,1
2,5 2,5
81,5 81,5
– –
– –
108,5 108,5
106 106
1 1
80
125 125
34 34
119 000 119 000
186 000 186 000
22 000 22 000
6 700 6 700
7 500 7 500
1,5 1,5
NN 3016 TN NN 3016 KTN
80
97 97
113 113
– –
– –
1,1 1,1
3 3
86,5 86,5
– –
– –
118,5 118,5
114 114
1 1
196
197
High-precision double row cylindrical roller bearings d 85 – 130 mm s
s
b K
B r1
D1
d
F
r2
ra
Da
da
d
d d1
ra
ra
ra
r2
D E
ra
ra
r1
Da
da
Da da
db
db
Da da
3 NNU 49 B/W33
Principal dimensions d
D
NNU 49 BK/W33
Basic load ratings dynamic static B
mm
C
C0
N
NN 30
NN 30 KTN
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1, D1 ≈
Abutment and fillet dimensions
E, F
b
K
r1, 2 min
s
da min
da max
db min
Da max
Da min
ra max
mm
85
130 130
34 34
125 000 125 000
204 000 204 000
23 200 23 200
6 300 6 300
7 000 7 000
1,55 1,55
NN 3017 TN9 NN 3017 KTN9
85
102 102
118 118
– –
– –
1,1 1,1
2,5 2,5
91,5 91,5
– –
– –
123,5 123,5
119 119
1 1
90
140 140
37 37
138 000 138 000
216 000 216 000
26 000 26 000
6 000 6 000
6 700 6 700
1,95 1,95
NN 3018 TN9 NN 3018 KTN9
90
109 109
127 127
– –
– –
1,5 1,5
2,8 2,8
98 98
– –
– –
132 132
129 129
1,5 1,5
95
145 145
37 37
142 000 142 000
232 000 232 000
27 500 27 500
5 600 5 600
6 300 6 300
2,05 2,05
NN 3019 TN9 NN 3019 KTN9
95
114 114
132 132
– –
– –
1,5 1,5
2,8 2,8
103 103
– –
– –
137 137
134 134
1,5 1,5
100
140 140 150 150
40 40 37 37
128 000 128 000 151 000 151 000
255 000 255 000 250 000 250 000
29 000 29 000 29 000 29 000
5 600 5 600 5 300 5 300
6 300 6 300 6 000 6 000
1,9 1,8 2,1 2,1
NNU 4920 B/W33 NNU 4920 BK/W33 NN 3020 TN9 NN 3020 KTN9
100
126 126 119 119
113 113 137 137
5,5 5,5 – –
3 3 – –
1,1 1,1 1,5 1,5
1,1 1,1 2,8 2,8
1,7 1,7 108 108
106,5 106,5 – –
111 111 – –
116 116 142 142
– – 139 139
1 1 1,5 1,5
105
145 145 160 160
40 40 41 41
130 000 130 000 190 000 190 000
260 000 260 000 305 000 305 000
29 000 29 000 36 000 36 000
5 300 5 300 5 000 5 000
6 000 6 000 5 600 5 600
2 1,9 2,7 2,7
NNU 4921 B/W33 NNU 4921 BK/W33 NN 3021 TN9 NN 3021 KTN9
105
131 131 125 125
118 118 146 146
5,5 5,5 – –
3 3 – –
1,1 1,1 2 2
1,1 1,1 1,8 1,8
1,7 1,7 115 115
111,5 111,5 – –
116 116 – –
121 121 150 150
– – 148 148
1 1 2 2
110
150 150 170 170
40 40 45 45
132 000 132 000 220 000 220 000
270 000 270 000 360 000 360 000
30 000 30 000 41 500 41 500
5 300 5 300 4 800 4 800
6 000 6 000 5 300 5 300
2,05 1,95 3,4 3,4
NNU 4922 B/W33 NNU 4922 BK/W33 NN 3022 TN9 NN 3022 KTN9
110
136 136 132 132
123 123 155 155
5,5 5,5 – –
3 3 – –
1,1 1,1 2 2
1,1 1,1 3,8 3,8
1,7 1,7 120 120
116,5 116,5 – –
121 121 – –
126 126 160 160
– – 157 157
1 1 2 2
120
165 165 180 180
45 45 46 46
176 000 176 000 229 000 229 000
340 000 340 000 390 000 390 000
37 500 37 500 44 000 44 000
4 800 4 800 4 500 4 500
5 300 5 300 5 000 5 000
2,8 2,65 3,7 3,7
NNU 4924 B/W33 NNU 4924 BK/W33 NN 3024 TN9 NN 3024 KTN9
120
151 151 142 142
134,5 134,5 165 165
5,5 5,5 – –
3 3 – –
1,1 1,1 2 2
1,1 1,1 3,8 3,8
1,7 1,7 130 130
126,5 126,5 – –
133 133 – –
137 137 170 170
– – 167 167
1 1 2 2
130
180 180 200 200
50 50 52 52
187 000 187 000 286 000 286 000
390 000 390 000 475 000 475 000
41 500 41 500 53 000 53 000
4 300 4 300 4 000 4 000
4 800 4 800 4 500 4 500
3,85 3,65 5,55 5,55
NNU 4926 B/W33 NNU 4926 BK/W33 NN 3026 TN9 NN 3026 KTN9
130
162 162 156 156
146 146 182 182
5,5 5,5 – –
3 3 – –
1,5 1,5 1,1 1,1
1,5 1,5 3,8 3,8
2,2 2,2 140 140
138 138 – –
144 144 – –
149 149 190 190
– – 183 183
1,5 1,5 2 2
198
199
High-precision double row cylindrical roller bearings d 140 – 240 mm s
s
b K
B r1
D1
d
F
r2
ra
Da
da
d
d d1
ra
ra
ra
r2
D E
ra
ra
r1
Da
da
Da da
db
db
Da da
3 NNU 49 B/W33
Principal dimensions d
D
NNU 49 BK/W33
Basic load ratings dynamic static B
mm
C
C0
N
NN 30
NN 30 KTN
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1, D1 ≈
Abutment and fillet dimensions
E, F
b
K
r1, 2 min
s
da min
da max
db min
Da max
Da min
ra max
mm
140
190 190 210
50 50 53
190 000 190 000 297 000
400 000 400 000 520 000
41 500 41 500 56 000
4 000 4 000 3 800
4 500 4 500 4 300
4,1 3,9 6
NNU 4928 B/W33 NNU 4928 BK/W33 NN 3028 K
140
172 172 166
156 156 192
5,5 5,5 –
3 3 –
1,5 1,5 2
1,5 1,5 3,8
2,2 2,2 150
148 148 –
154 154 –
159 159 200
– – 194
1,5 1,5 2
150
210 210 225
60 60 56
330 000 330 000 330 000
655 000 655 000 570 000
71 000 71 000 62 000
3 800 3 800 3 600
4 300 4 300 4 000
6,25 6,15 7,3
NNU 4930 B/W33 NNU 4930 BK/W33 NN 3030 K
150
191 191 178
168,5 168,5 206
5,5 5,5 –
3 3 –
2 2 2,1
2 2 4
2 2 161
160 160 –
166 166 –
172 172 214
– – 208
2 2 2
160
220 220 240
60 60 60
330 000 330 000 369 000
680 000 680 000 655 000
72 000 72 000 69 500
3 600 3 600 3 400
4 000 4 000 3 800
6,6 6,3 8,8
NNU 4932 B/W33 NNU 4932 BK/W33 NN 3032 K
160
201 201 190
178,5 178,5 219
5,5 5,5 –
3 3 –
2 2 2,1
2 2 5
2 2 171
170 170 –
176 176 –
182 182 229
– – 221
2 2 2
170
230 230 260
60 60 67
336 000 336 000 457 000
695 000 695 000 815 000
73 500 73 500 85 000
3 400 3 400 3 000
3 800 3 800 3 400
6,95 6,65 12
NNU 4934 B/W33 NNU 4934 BK/W33 NN 3034 K
170
211 211 204
188,5 188,5 236
5,5 5,5 –
3 3 –
2 2 2,1
2 2 5
2 2 181
180 180 –
186 186 –
192 192 249
– – 238
2 2 2
180
250 250 280
69 69 74
402 000 402 000 561 000
850 000 850 000 1 000 000
88 000 88 000 102 000
3 000 3 000 2 800
3 400 3 400 3 200
10,5 10 16
NNU 4936 B/W33 NNU 4936 BK/W33 NN 3036 K
180
226 226 218
202 202 255
8,3 8,3 –
4,5 4,5 –
2 2 2,1
2 2 5
2,3 2,3 191
190 190 –
199 199 –
205 205 269
– – 257
2 2 2
190
260 260 290
69 69 75
402 000 402 000 594 000
880 000 880 000 1 080 000
90 000 90 000 108 000
2 800 2 800 2 600
3 200 3 200 3 000
11 10,5 17
NNU 4938 B/W33 NNU 4938 BK/W33 NN 3038 K
190
236 236 228
212 212 265
8,3 8,3 –
4,5 4,5 –
2 2 2,1
2 2 5
1,1 1,1 201
200 200 –
209 209 –
215 215 279
– – 267
2 2 2
200
280 280 310
80 80 82
484 000 484 000 644 000
1 040 000 1 040 000 1 140 000
106 000 106 000 118 000
2 600 2 600 2 400
3 000 3 000 2 800
15 14,5 21
NNU 4940 B/W33 NNU 4940 BK/W33 NN 3040 K
200
253 253 242
225 225 282
11,1 11,1 –
6 6 –
2,1 2,1 2,1
2,1 2,1 6,5
3,7 3,7 211
211 211 –
222 222 –
228 228 299
– – 285
2 2 2
220
300 300 340
80 80 90
512 000 512 000 809 000
1 140 000 1 140 000 1 460 000
114 000 114 000 143 000
2 400 2 400 2 200
2 800 2 800 2 600
16,5 16 27,5
NNU 4944 B/W33 NNU 4944 BK/W33 NN 3044 K
220
273 273 265
245 245 310
11,1 11,1 –
6 6 –
2,1 2,1 3
2,1 2,1 7,4
3,7 3,7 233
231 231 –
242 242 –
249 249 327
– – 313
2 2 2,5
240
320 320 360
80 80 92
528 000 528 000 842 000
1 220 000 1 220 000 1 560 000
118 000 118 000 153 000
2 200 2 200 2 000
2 600 2 600 2 400
17,5 16,5 30,5
NNU 4948 B/W33 NNU 4948 BK/W33 NN 3048 K
240
293 293 285
265 265 330
11,1 1,1 –
6 6 –
2,1 2,1 3
2,1 2,1 7,4
3,7 3,7 253
251 251 –
262 262 –
269 269 347
– – 333
2 2 2,5
200
201
High-precision double row cylindrical roller bearings d 260 – 280 mm s
s
b K
B r1
D1
d
F
r2
ra
Da
da
d
d d1
ra
ra
ra
r2
D E
ra
ra
r1
Da
da
Da da
db
db
Da da
3 NNU 49 B/W33
Principal dimensions d
D
NNU 49 BK/W33
Basic load ratings dynamic static B
mm
C
C0
N
NN 30
NN 30 KTN
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1, D1 ≈
Abutment and fillet dimensions
E, F
b
K
r1, 2 min
s
da min
da max
db min
Da max
Da min
ra max
mm
260
360 360 400
100 100 104
748 000 748 000 1 020 000
1 700 000 1 700 000 1 930 000
163 000 163 000 183 000
2 000 2 000 1 900
2 400 2 400 2 200
30,5 28,5 44
NNU 4952 B/W33 NNU 4952 BK/W33 NN 3052 K
260
326 326 312
292 292 364
13,9 13,9 –
7,5 7,5 –
2,1 2,1 4
2,1 2,1 7,4
4,5 4,5 276
271 271 –
288 288 –
296 296 384
– – 367
2 2 3
280
380 380 420
100 100 106
765 000 765 000 1 080 000
1 800 000 1 800 000 2 080 000
170 000 170 000 196 000
1 900 1 900 1 800
2 200 2 200 2 000
32,5 30,5 47,5
NNU 4956 B/W33 NNU 4956 BK/W33 NN 3056 K
280
346 346 332
312 312 384
13,9 13,9 –
7,5 7,5 –
2,1 2,1 4
2,1 2,1 12,4
4,5 4,5 296
291 291 –
308 308 –
316 316 404
– – 387
2 2 3
202
203
High-precision single row cylindrical roller bearings d 40 – 95 mm B
s r2 r4
ra
r1 r3
D E
d
d1
da
Da
3
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
E
r1, 2 min
r3, 4 min
s
da min
da max
Da max
mm
Da min
ra max
–
40
68 68
15 15
25 100 24 200
28 000 26 500
3 200 3 050
15 000 23 700
17 000 32 800
0,19 0,19
N 1008 KTN N 1008 KTNHA
40
50,6 50,6
61 61
1 1
0,6 0,6
3 3
45 45
59 59
63 63
62 62
1 1
45
75 75
16 16
29 200 28 100
32 500 31 000
3 800 3 650
13 000 21 300
15 000 29 600
0,24 0,24
N 1009 KTN N 1009 KTNHA
45
56,3 56,3
67,5 67,5
1 1
0,6 0,6
3 3
50 50
65 65
70 70
69 69
1 1
50
80 80
16 16
30 800 29 700
36 500 34 500
4 250 4 050
12 000 19 600
14 000 27 300
0,26 0,26
N 1010 KTN N 1010 KTNHA
50
61,3 61,3
72,5 72,5
1 1
0,6 0,6
3 3
55 55
70 70
75 75
74 74
1 1
55
90 90
18 18
40 200 39 100
48 000 46 500
5 700 5 500
11 000 17 600
13 000 24 500
0,39 0,39
N 1011 KTN N 1011 KTNHA
55
68,2 68,2
81 81
1,1 1,1
0,6 0,6
3 3
61,5 61,5
79 79
83,5 83,5
82 82
1 1
60
95 95
18 18
42 900 41 300
53 000 51 000
6 300 6 100
10 000 16 400
12 000 22 800
0,41 0,41
N 1012 KTN N 1012 KTNHA
60
73,3 73,3
86,1 86,1
1,1 1,1
0,6 0,6
3 3
66,5 66,5
84 84
88,5 88,5
87 87
1 1
65
100 100
18 18
44 600 44 000
58 500 56 000
6 800 6 550
9 500 15 500
11 000 21 500
0,44 0,44
N 1013 KTN N 1013 KTNHA
65
78,2 78,2
91 91
1,1 1,1
0,6 0,6
3 3
71,5 71,5
89 89
93,5 93,5
92 92
1 1
70
110 110
20 20
57 200 55 000
75 000 72 000
8 650 8 300
9 000 14 100
10 000 19 600
0,62 0,62
N 1014 KTN N 1014 KTNHA
70
85,6 85,6
100 100
1,1 1,1
0,6 0,6
3,5 3,5
76,5 76,5
98 98
103,5 103,5
101 101
1 1
75
115 115
20 20
56 100 55 000
75 000 72 000
8 800 8 500
8 500 13 300
9 500 18 600
0,65 0,65
N 1015 KTN N 1015 KTNHA
75
90,6 90,6
105 105
1,1 1,1
0,6 0,6
3,5 3,5
81,5 81,5
102 102
108,5 108,5
106 106
1 1
80
125 125
22 22
69 300 67 100
93 000 90 000
11 000 10 600
8 000 12 400
9 000 17 300
0,89 0,88
N 1016 KTN N 1016 KTNHA
80
97 97
113 113
1,1 1,1
0,6 0,6
3,5 3,5
86,5 86,5
110 110
118,5 118,5
114 114
1 1
85
130 130
22 22
73 700 70 400
102 000 98 000
11 600 11 200
7 500 11 800
8 500 16 500
0,9 0,89
N 1017 KTN9 N 1017 KTNHA
85
102 102
118 118
1,1 1,1
0,6 0,6
3,5 3,5
91,5 91,5
115 115
123,5 123,5
119 119
1 1
90
140 140
24 24
79 200 76 500
108 000 104 000
12 900 12 500
7 000 11 000
8 000 15 300
1,2 1,19
N 1018 KTN9 N 1018 KTNHA
90
109 109
127 127
1,5 1,5
1 1
4 4
98 98
124 124
132 132
129 129
1,5 1,5
95
145 145
24 24
84 200 80 900
116 000 112 000
14 000 13 400
6 700 10 500
7 500 14 700
1,25 1,25
N 1019 KTN9 N 1019 KTNHA
95
114 114
132 132
1,5 1,5
1 1
4 4
103 103
129 129
137 137
134 134
1,5 1,5
204
205
High-precision single row cylindrical roller bearings d 100 – 120 mm B
s r2 r4
ra
r1 r3
D E
d
d1
da
Da
3
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
E
r1, 2 min
r3, 4 min
s
da min
da max
Da max
mm
Da min
ra max
–
100
150 150
24 24
88 000 85 800
125 000 120 000
14 600 14 300
6 700 10 600
7 500 14 700
1,31 1,31
N 1020 KTN9 N 1020 KTNHA
100
119 119
137 137
1,5 1,5
1 1
4 4
108 108
134 134
142 142
139 139
1,5 1,5
105
160 160
26 26
110 000 153 000 108 000 146 000
18 000 17 300
6 300 9 600
7 000 13 300
1,65 1,64
N 1021 KTN9 N 1021 KTNHA
105
125 125
146 146
2 2
1,1 1,1
4 4
114 114
143 143
151 151
148 148
2 2
110
170 170
28 28
128 000 180 000 125 000 173 000
20 800 20 000
5 600 9 000
6 300 12 600
2,04 2,03
N 1022 KTN9 N 1022 KTNHA
110
132 132
155 155
2 2
1,1 1,1
4 4
119 119
152 152
161 161
157 157
2 2
120
180 180
28 28
134 000 196 000 130 000 186 000
22 000 21 200
5 300 8 400
6 000 11 700
2,2 2,18
N 1024 KTN9 N 1024 KTNHA
120
142 142
165 165
2 2
1,1 1,1
4 4
129 129
162 162
171 171
167 167
2 2
206
207
Hybrid high-precision single row cylindrical roller bearings d 40 – 95 mm B
s r2 r4
ra
r1 r3
D E
d
d1
da
Da
3
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
d1 ≈
Abutment and fillet dimensions
E
r1, 2 min
r3, 4 min
s
mm
da min
da max
Da max
mm
Da min
ra max
–
40
68 68
15 15
25 100 24 200
28 000 26 500
3 200 3 050
18 100 26 400
20 900 36 500
0,17 0,17
N 1008 KTN/HC5 N 1008 KTNHA/HC5
40
50,6 50,6
61 61
1 1
0,6 0,6
3 3
45 45
59 59
63 63
62 62
1 1
45
75 75
16 16
29 200 28 100
32 500 31 000
3 800 3 650
16 300 23 800
18 800 32 900
0,22 0,21
N 1009 KTN/HC5 N 1009 KTNHA/HC5
45
56,3 56,3
67,5 67,5
1 1
0,6 0,6
3 3
50 50
65 65
70 70
69 69
1 1
50
80 80
16 16
30 800 29 700
36 500 34 500
4 250 4 050
15 100 21 900
17 400 30 300
0,23 0,23
N 1010 KTN/HC5 N 1010 KTNHA/HC5
50
61,3 61,3
72,5 72,5
1 1
0,6 0,6
3 3
55 55
70 70
75 75
74 74
1 1
55
90 90
18 18
40 200 39 100
48 000 46 500
5 700 5 500
13 500 19 700
15 600 27 200
0,35 0,35
N 1011 KTN/HC5 N 1011 KTNHA/HC5
55
68,2 68,2
81 81
1,1 1,1
0,6 0,6
3 3
61,5 61,5
79 79
83,5 83,5
82 82
1 1
60
95 95
18 18
42 900 41 300
53 000 51 000
6 300 6 100
12 600 18 400
14 500 25 400
0,37 0,37
N 1012 KTN/HC5 N 1012 KTNHA/HC5
60
73,3 73,3
86,1 86,1
1,1 1,1
0,6 0,6
3 3
66,5 66,5
84 84
88,5 88,5
87 87
1 1
65
100 100
18 18
44 600 44 000
58 500 56 000
6 800 6 550
11 800 17 300
13 700 23 900
0,39 0,39
N 1013 KTN/HC5 N 1013 KTNHA/HC5
65
78,2 78,2
91 91
1,1 1,1
0,6 0,6
3 3
71,5 71,5
89 89
93,5 93,5
92 92
1 1
70
110 110
20 20
57 200 55 000
75 000 72 000
8 650 8 300
10 800 15 700
12 400 21 800
0,55 0,55
N 1014 KTN/HC5 N 1014 KTNHA/HC5
70
85,6 85,6
100 100
1,1 1,1
0,6 0,6
3,5 3,5
76,5 76,5
98 98
103,5 103,5
101 101
1 1
75
115 115
20 20
56 100 55 000
75 000 72 000
8 800 8 500
10 200 14 900
11 800 20 600
0,57 0,57
N 1015 KTN/HC5 N 1015 KTNHA/HC5
75
90,6 90,6
105 105
1,1 1,1
0,6 0,6
3,5 3,5
81,5 81,5
102 102
108,5 108,5
106 106
1 1
80
125 125
22 22
69 300 67 100
93 000 90 000
11 000 10 600
9 500 13 900
11 000 19 200
0,79 0,79
N 1016 KTN/HC5 N 1016 KTNHA/HC5
80
97 97
113 113
1,1 1,1
0,6 0,6
3,5 3,5
86,5 86,5
110 110
118,5 118,5
114 114
1 1
85
130 130
22 22
73 700 70 400
10 2000 98 000
11 600 11 200
9 100 13 200
10 400 18 300
0,80 0,79
N 1017 KTN9/HC5 N 1017 KTNHA/HC5
85
102 102
118 118
1,1 1,1
0,6 0,6
3,5 3,5
91,5 91,5
115 115
123,5 123,5
119 119
1 1
90
140 140
24 24
79 200 76 500
108 000 104 000
12 900 12 500
8 400 12 300
9 700 17 000
1,08 1,07
N 1018 KTN9/HC5 N 1018 KTNHA/HC5
90
109 109
127 127
1,5 1,5
1 1
4 4
98 98
124 124
132 132
129 129
1,5 1,5
95
145 145
24 24
84 200 80 900
116 000 112 000
14 000 13 400
8 100 11 800
9 300 16 300
1,12 1,12
N 1019 KTN9/HC5 N 1019 KTNHA/HC5
95
114 114
132 132
1,5 1,5
1 1
4 4
103 103
129 129
137 137
134 134
1,5 1,5
208
209
Hybrid high-precision single row cylindrical roller bearings d 100 – 120 mm B
s r2 r4
ra
r1 r3
D E
d
d1
da
Da
3
Principal dimensions d
D
Basic load ratings dynamic static B
mm
C
C0
N
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
d1 ≈
Abutment and fillet dimensions
E
r1, 2 min
r3, 4 min
s
mm
da min
da max
Da max
mm
Da min
ra max
–
100
150 150
24 24
88 000 85 800
125 000 120 000
14 600 14 300
8 100 11 800
9 300 16 400
1,17 1,17
N 1020 KTN9/HC5 N 1020 KTNHA/HC5
100
119 119
137 137
1,5 1,5
1 1
4 4
108 108
134 134
142 142
139 139
1,5 1,5
105
160 160
26 26
110 000 153 000 108 000 146 000
18 000 17 300
7 300 10 700
8 400 14 800
1,44 1,44
N 1021 KTN9/HC5 N 1021 KTNHA/HC5
105
125 125
146 146
2 2
1,1 1,1
4 4
114 114
143 143
151 151
148 148
2 2
110
170 170
28 28
128 000 180 000 125 000 173 000
20 800 20 000
6 900 10 100
8 000 14 000
1,79 1,78
N 1022 KTN9/HC5 N 1022 KTNHA/HC5
110
132 132
155 155
2 2
1,1 1,1
4 4
119 119
152 152
161 161
157 157
2 2
120
180 180
28 28
134 000 196 000 130 000 186 000
22 000 21 200
6 400 9 400
7 400 13 000
1,92 1,92
N 1024 KTN9/HC5 N 1024 KTNHA/HC5
120
142 142
165 165
2 2
1,1 1,1
4 4
129 129
162 162
171 171
167 167
2 2
210
211
Double direction angular contact thrust ball bearings Contents
Double direction angular contact thrust ball bearings Two different designs Bearings of series 2344(00) Bearings of series BTM Hybrid double direction angular contact thrust ball bearings Marking of double direction angular contact thrust ball bearings Bearing data general Effect of interference fit on preload Cages Speed ratings Equivalent dynamic bearing load Equivalent static bearing load Designation system Product tables Double direction angular contact thrust ball bearings Hybrid double direction angular contact ball bearings
214 214 215 216 217 217 218 221 221 222 223 223 224 225 226 230
213
4
4 Double direction angular contact thrust ball bearings
Double direction angular contact thrust ball bearings Two different designs SKF offers two main families of double direction angular contact thrust ball bearings: the series 2344(00) (➔ fig 1 ) and the series BTM (➔ fig 2 ). Two basic variants exist for series BTM: Series BTM – A with 30° contact angle and Series BTM – B with 40° contact angle. These bearings are able to locate a spindle axially in both directions, and are intended for mounting at the side of the
Double direction angular contact thrust ball bearings: series 2344(00)
double row, or single row cylindrical roller bearings of series NN 30 K and N 10 K, having the same bore size and outside diameters. The outside diameter of the housing washer, is however, made to tolerances such that sufficient radial clearance to the housing bore seating is obtained. This is to ensure that the thrust bearing is only subjected to axial loads. An additional benefit is the simplified machining of the housing bore.
1
The bearings belonging to series 2344(00) are of separable design: they have a one piece housing washer, two ball and cage assemblies with a large number of balls, and two shaft washers separated by a spacer sleeve (➔ fig 3 ). When mounted the bearings become preloaded. Bearings of series 2344(00)
have a contact angle of 60°. To facilitate efficient lubrication, the bearings have a groove and three lubrication holes in the housing washer. The preload, the 60° contact angle, together with the large number of balls, and cage assembly impart high axial stiffness to the bearings. A re-designed cage makes them suitable for relatively high speed operations.
4
Double direction angular contact thrust ball bearings: series BTM Fig
Bearings of series 2344(00)
Series 2344(00) cross section Fig
2
Fig
3
60° contact angle
214
215
4 Double direction angular contact thrust ball bearings
Bearings of series BTM Bearings of series BTM are non-separable and designed as single direction angular contact thrust ball bearings, although always supplied in back-to-back sets, and are able to carry thrust loads in both directions. When mounted the bearings become preloaded. The bearings have a contact angle of 30° (➔ fig 4 ) or 40° (➔ fig 5 ) and the same bore and outside diameter as series 2344(00), but a 25 % lower sectional height (width), which makes them particularly suitable for very compact arrangements. They do not have the same high load carrying capacity and axial stiffness as those of series 2344(00), but can operate at higher speeds. Since bearings of series BTM are only intended to accommodate axial loads, their axial load carrying capacity is quoted in the bearing tables, although by ISO definition they are radial bearings, by virtue of having a 30° or 40° contact angle.
Series BTM – A
Series BTM – B Fig
30° contact angle
216
4
Fig
5
Hybrid double direction angular contact thrust ball bearings
Marking of double direction angular contact thrust ball bearings
If the performance required is close to all-steel bearing limits, or if higher rigidity or longer life are needed, it is recommended to switch from an all-steel to a hybrid double direction angular contact thrust ball bearing. SKF is prepared to supply the bearings of series 2344(00) and BTM equipped with ceramic balls. The hybrid execution is identified by the suffix HC. More details concerning the advantages offered by ceramic material can be found in the chapter Principles of bearing selection and application, section material for high-precision bearings page 9.
The bearing rings carry several markings for identification purposes. Each bearing is marked with the complete designation. Bearings of the series 2344(00) are of separable design; therefore to avoid wrong positioning of the inner washers and spacers, each component – i.e. inner rings, outer rings and the spacer – is marked with a serial number. This also prevents the mixing of components from two bearings with different serial numbers. Bearings of series BTM are non separable and matched into back-to-back sets of two. In addition to the complete designation, the actual deviation of the inner bore diameter from nominal are marked on the inner ring; this is to facilitate the selection of the actual bore in order to obtain the desired fits after mounting. A ‘V’-shaped marking is made on the outside diameter of the bearings. The bearings should be mounted in the order shown by this marking to obtain correct preload. It also indicates how the set should be mounted compared with the axial load. The point of the ‘V’ gives the direction in which the axial load should act on the inner ring(s). Each bearing of a series BTM bearing set is marked with the complete designation of the bearing set. To prevent mixing of bearings belonging to different sets, a serial number is shown on the face of the inner ring of each bearing.
40° contact angle
217
4
4 Double direction angular contact thrust ball bearings
Bearing data general Dimensions The dimensions of SKF double direction angular contact thrust ball bearings are not standardised, but are generally accepted on the market. The bore and outside diameters of bearings of series 2344(00), BTM – A and BTM – B, do however, correspond to those of Diameter Series 0 according to ISO 15:1998. Tolerances SKF double direction angular contact thrust ball bearings of series 2340(00) are made to tolerance class SP (Special Precision) specifications as standard. Bearings made to tolerance class UP (Ultra Precision) can be supplied to order. SKF double direction angular contact thrust ball bearings of series BTM – A and BTM – B are made to tolerance class P4C for enhanced running accuracy and even more precise bore diameters.
The values for class SP, UP and P4C tolerances are given in the Tables 1 , 2 and 3 . Hybrid double direction angular contact thrust ball bearings are made to the same tolerances as the corresponding all-steel type.
Class SP tolerances for 2344(00) angular contact thrust ball bearing series Table
d over
incl.
mm
∆ds high
low
µm
max
∆Ts high
µm
µm
low
d over
incl.
mm
∆ds high
2
low
µm
Table
∆Ts high
µm
µm
low
d over
incl.
mm
∆ds high
low
µm
Si1) max
∆B1s high
µm
µm
low
18 30 50
30 50 80
+1 +1 +2
–9 –11 –14
3 3 4
+50 +60 +70
–80 –100 –120
18 30 50
30 50 80
0 0 0
–6 –8 –9
1,5 1,5 2
+50 +60 +70
– 80 – 100 – 120
50 80 120
80 120 180
0 0 0
–7 –8 –10
3 4 4
0 0 0
–100 –200 –250
80 120 180
120 180 250
+3 +3 +4
–18 –21 –26
4 5 5
+85 +95 +120
–140 –160 –200
80 120 180
120 180 250
0 0 0
– 10 – 13 – 15
2 3 3
+85 +95 +120
– 140 – 160 – 200
180
250
0
–14
5
0
–250
low
∆Cs high
low
∆Cs high
∆Ds high
low
∆C1s high
low
D over
incl.
mm
∆Ds high
Housing washer
µm
Se low
µm
incl.
mm
30 50 80
50 80 120
–20 –24 –28
–27 –33 –38
0 0 0
– 60 – 60 – 60
120 150 180
150 180 250
–33 –33 –37
–44 –46 –52
0 0 0
– 60 – 60 – 60
250
315
–41
–59
0
– 60
1)
D over
Values are identical to those of shaft washer of same bearing
The tolerance values quoted must be considered approximate, as the raceway runout is measured in the direction of the ball load. When the bearings have been mounted, the axial runout is generally smaller than quoted in the table
∆Ds high
Outer ring
µm
Se low
µm
D over
incl.
mm
30 50 80
50 80 120
– 20 – 24 – 28
– 27 – 33 – 38
0 0 0
– 60 – 60 – 60
120 150 180
150 180 250
– 33 – 33 – 37
– 44 – 46 – 52
0 0 0
– 60 – 60 – 60
250
315
– 41
– 59
0
– 60
1)
3
Inner ring
max
Si1)
4
Class P4C tolerances for series BTM – A and BTM – B angular contact thrust ball bearings
Shaft washer and bearing height
Housing washer
218
Table
1
Shaft washer and bearing height Si1)
Class UP tolerances for series 2344(00) angular contact thrust ball bearings
Values are identical to those of shaft washer of same bearing
The tolerance values quoted must be considered approximate, as the raceway runout is measured in the direction of the ball load. When the bearings have been mounted, the axial runout is generally smaller than quoted in the table
µm
Se
µm
80 120 150
120 150 180
–28 –33 –33
–38 –44 –46
0 0 0
–100 –200 –250
180 250
250 315
–37 –41
–52 –59
0 0
–250 –250
1)
Values are identical to those of shaft washer of same bearing
The tolerance values quoted must be considered approximate, as the raceway runout is measured in the direction of the ball load. When the bearings have been mounted, the axial runout is generally smaller than quoted in the table
219
4 Double direction angular contact thrust ball bearings Preload The preload of double direction angular contact thrust ball bearings series 2344(00), BTM – A and BTM – B is predetermined during manufacture. This is done by individually setting the distance sleeve length for bearings of series 2344(00) and by a precisely adjusted standout of inner versus outer ring for bearing pairs of series BTM – A and BTM – B. The bearings of series 2344(00) have one standard preload class while bearings of series BTM – A and BTM – B are available in two different preload classes, identified by suffixes A and B respectively.
For bearings of the series 2344(00) series, which are of separable design; rings, washers nor spacers shall be exchanged in position (i.e. the position of inner rings must not be reversed) neither mixed with rings belonging to other bearings; otherwise the predetermined preload will not be achieved. Similarly, a bearing in a set of series BTM shall not be mounted together with a bearing taken from another set. The axial preload values for SKF double direction angular contact thrust ball bearings are given in Tables 4 and 5 .
Table Bore diameter
Standard preload
Bore diameter
Standard preload
mm
N
mm
N
40 45 50 55 60 65
360 390 415 440 470 490
100 110 120 130 140 150
690 735 800 870 940 1 015
70 75 80 85 90 95
515 545 575 600 625 655
160 170 180 190 200
1 100 1 185 1 290 1 385 1 525
4
Axial preload values: 2344(00) series
Effect of interference fit on preload The preload values listed in the Tables 4 and 5 refer to unmounted bearings. Preload may increase due to interference fits where the inner rings are not free to decrease in diameter, as a consequence of the axial load. In unmounted condition, the effect of the axial measuring load due to ring wall thickness is negligible. When fitting bearings on a shaft, interference between shaft and bearing shaft washers (inner rings) can cause the raceways to expand, generating an increase in preload. Double direction angular thrust ball bearings are usually fitted to the shaft seating to tolerance h4. If interference occurs, the relation between axial preload and radial (diametrical) preload increase can be expressed as: δa = δr/tan α where: δa = axial preload increase δr = radial preload increase α = bearing contact angle It is not necessary to make corrections for the mounted preload as long as there is no interference fit.
Table Bore diameter
Series BTM – A Preload Preload Class A Class B
mm
N
60 65 70 80 85 90
200 200 250 300 300 400
450 450 600 750 750 1 000
250 250 350 400 400 550
720 720 950 1 200 1 200 1 450
100 110 120 130
400 600 600 800
1 000 1 400 1 500 1 900
550 750 850 1 050
1 650 2 250 2 450 3 000
220
Series BTM – B Preload Preload Class A Class B
5
Cages SKF double direction angular contact thrust ball bearings of series 2344(00) have two separated cages that are ball-centred. They can either be of machined brass – identified by the suffix M1– or of heat stabilised, glass fibre reinforced polyamide 6,6 – identified by the suffix TN9. Depending on the bearing size, the former or the latter design is considered standard (➔ Table 6 page 222). The same cage design and material (TN9) is used for bearings of series BTM – A and BTM – B. The cages are suited to withstand load cycles and rapid speed changes (in direction and value) and also to ensure good grease retention and stable conditions for preloaded bearings. Lubricants normally used for rolling bearings have no detrimental effect on the properties of the polyamide cage, with the exception of some synthetic oils and greases based on synthetic oils. Other exceptions are lubricants with a high content of EP additives when used at elevated temperatures. The bearings equipped with TN9 cages may be used without restriction at temperatures up to +120°C. Higher temperatures can be tolerated for short periods without any negative effect on the material, provided that long periods at much lower temperatures follow.
Axial preload values: BTM – A and BTM – B series
221
4
4 Double direction angular contact thrust ball bearings
Speed ratings The speed ratings quoted in the product tables are guideline values and are valid, provided that the bearings are lightly loaded, that they are light preloaded and that the transport of heat away from the bearing position is good. In the case of
bearings of series BTM – A and BTM – B all-steel or hybrid, a speed reduction factor of 0,55 has to be considered in case of preload of class B. There is no need to consider speed reduction factors due to preload for bearings of series 2344(00), BTM – A or BTM – B with preload class A.
Equivalent dynamic bearing load
Equivalent static bearing load
Double direction angular contact thrust ball bearings are subjected only to axial load. If this acts centrically, then
As per above – equivalent dynamic bearing load
P = Fa
Po = Fa
4 Table Bearing dimensions bore code
2344(00) series brass polyamide cage (M1) cage (TN9)
BTM – A, BTM – B polyamide cage
bore diameter
05 06 07 08 09 10
25 30 35 40 45 50
STD STD STD STD STD STD
– – – – – –
– – – – – –
11 12 13 14 15 16
55 60 65 70 75 80
STD – – – STD OPT
– STD STD STD STD
– STD STD STD – STD
17 18 19 20 22 24
85 90 95 100 110 120
OPT OPT STD OPT STD OPT
STD STD – STD – STD
STD STD – STD SD STD
26 28 30 32 34 36
130 140 150 160 170 180
OPT STD STD STD STD STD
STD – – – – –
STD – – – – –
38 40
190 200
STD STD
– –
– –
6
STD = standard cage; OPT = on request; SD = special design Note: the BTM bearings have no cage suffix as only one type is available
222
223
4 Double direction angular contact thrust ball bearings
Designation system
Product tables
Designation system of double direction angular contact thrust ball bearings Table
BTM 90
/ HC P4C DB A
B
2344 20
7
TN9 / HC SP
4
Bearing series BTM Double direction angular contact thrust ball bearing, High-speed series 2344 Double direction angular contact thrust ball bearing Bore diameter 05 (×5) 25 mm bore diameter (series 2344 only) I 40 (×5) 200 mm bore diameter (series 2344 only) 60 I 130
bore diameter, mm, uncoded (series BTM, only) bore diameter, mm, uncoded (series BTM, only)
Internal design B Internal design code (series 2344 and brass cage only), blank for series BTM Contact angle – 60° (blank for series 2344 only) A 30° (for series BTM – A only) B 40° (for series BTM – B only) Cage design and material – Rolling elements riding, polyamide 6,6 (series BTM only) M1 Rolling elements riding, machined brass (series 2344 only) TN9 Rolling elements riding, grass fibre reinforced polyamide 6,6 (series 2344 only) Rolling element material – Chromium steel HC Silicon nitride Precision class SP Special precision (P4 running accuracy, series 2344 only) UP Ultra precision (P2 running accuracy, series 2344 only) P4C Special precision – series BTM only Matching DB
Preload A B G..
224
Set of two bearing matched back-to-back as standard (series BTM only) Blank for series 2344
Light preload (series BTM – A only) Heavy (series BTM – B only) Special preload, daN (series BTM only)
225
Double direction angular contact thrust ball bearings d 35 – 90 mm b
K r4 r3 r2
r4 r1
d d1
D
D1
d1
H
2344(00)
BTM – B
D
Basic load ratings dynamic static H
mm
C
C0
N
rb ra
r2
C H
Principal dimensions d
r1
rb
r3
ra
da
Da
Da
da
4 BTM – A
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
d1 ≈
Abutment and fillet dimensions
C, D1
K
b
r1, 2 min
r3, 4 min
mm
da min
Da min
ra max
ra max
58
1
0,1
mm
35
62
34
18 600
49 000
1 830
10 000
13 000
0,38
234407 BM1
35
53
40
68
36
21 600
60 000
2 240
9 500
12 000
0,46
234408 BM1
40
58,5
18
3
5,5
1
0,15
50
64
1
0,1
45
75
38
24 700
71 000
2 600
9 000
11 000
0,58
234409 BM1
45
65
19
3
5,5
1
0,15
56
71
1
0,1
50
80
38
25 500
78 000
2 850
8 500
10 000
0,62
234410 BM1
50
70
19
3
5,5
1
0,15
61
76
1
0,1
55
90
44
33 800
104 000
3 800
7 000
8 500
0,94
234411 BM1
55
78
22
3
5,5
1,1
0,3
68
85
1
0,3
60
95 95 95
33 33 44
26 500 31 000 34 500
62 000 71 000 108 000
2 500 2 800 4 000
9 300 8 300 7 000
11 900 10 600 8 500
0,77 0,77 1
BTM 60 A/DB BTM 60 B/DB 234412 TN9
60
75,9 75,9 83
89 89 22
– – 3
– – 5,5
1,1 1,1 1,1
0,6 0,6 0,3
67 67 73
89 89 90
1 1 1
0,6 0,6 0,3
65
100 100 100
33 33 44
27 500 32 500 35 800
68 000 76 500 116 000
2 600 2 900 4 300
8 700 7 800 6 700
11 200 10 000 8 000
0,82 0,82 1,05
BTM 65 A/DB BTM 65 B/DB 234413 TN9
65
80,9 80,9 88
94,3 94,3 22
– – 3
– – 5,5
1,1 1,1 1,1
0,6 0,6 0,3
75 75 78
94 94 95
1 1 1
0,6 0,6 0,3
70
110 110 110 115
36 36 48 48
33 500 40 000 43 600 44 200
83 000 95 000 143 000 150 000
3 150 3 600 5 300 5 600
8 000 7 200 6 300 6 000
10 200 9 100 7 500 7 000
1,12 1,12 1,45 1,55
BTM 70 A/DB BTM 70 B/DB 234414 TN9 234415 BM1
70
88,6 88,6 97 102
103,6 103,6 24 24
– – 3 3
– – 5,5 5,5
1,1 1,1 1,1 1,1
0,6 0,6 0,3 0,3
82 82 85 90
104 104 105 110
1 1 1 1
0,6 0,6 0,3 0,3
80
125 125 125
40,5 40,5 54
41 500 49 000 54 000
104 000 120 000 180 000
3 900 4 400 6 550
7 000 6 300 5 300
9 000 8 000 6 300
1,59 1,59 2,1
BTM 80 A/DB BTM 80 B/DB 234416 TN9
80
100,8 100,8 110
118,2 118,2 27
– – 4,5
– – 8,3
1,1 1,1 1,1
0,6 0,6 0,3
93 93 97
118 118 119
1 1 1
0,6 0,6 0,3
85
130 130 130
40,5 40,5 54
41 500 50 000 54 000
110 000 125 000 190 000
3 900 4 500 6 700
6 700 6 000 5 300
8 600 7 500 6 300
1,69 1,69 2,2
BTM 85 A/DB BTM 85 B/DB 234417 TN9
85
105,8 105,8 115
123,2 123,2 27
– – 4,5
– – 8,3
1,1 1,1 1,1
0,6 0,6 0,3
98 98 102
124 124 124
1 1 1
0,6 0,6 0,3
90
140 140 140
45 45 60
49 000 57 000 62 400
125 000 143 000 220 000
4 470 5 100 7 650
6 300 5 600 4 800
8 000 7 000 5 600
2,22 2,22 3
BTM 90 A/DB BTM 90 B/DB 234418 TN9
90
113 113 123
132 132 30
– – 4,5
– – 8,3
1,5 1,5 1,5
0,6 0,6 0,3
104 104 109
132 132 132
1,5 1,5 1,5
0,6 0,6 0,3
226
17
3
5,5
1
0,15
45
227
Double direction angular contact thrust ball bearings d 95 – 200 mm b
K r4 r3 r2
r4 r1
d d1
D
D1
d1
H
2344(00)
BTM – B
D
Basic load ratings dynamic static H
mm
C
C0
N
rb ra
r2
C H
Principal dimensions d
r1
rb
r3
ra
da
Da
Da
da
4 BTM – A
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
d1 ≈
Abutment and fillet dimensions
C, D1
K
b
r1, 2 min
r3, 4 min
mm
da min
Da min
ra max
ra max
mm
95
145
60
63 700
232 000
7 800
4 800
5 600
3,05
234419 BM1
95
128
30
4,5
8,3
1,5
0,3
114
137
1,5
0,3
100
150 150 150
45 45 60
51 000 61 000 66 300
140 000 163 000 245 000
4 740 5 400 8 150
6 000 5 300 4 800
7 500 6 700 5 600
2,45 2,45 3,15
BTM 100 A/DB BTM 100 B/DB 234420 TN9
100
123 123 133
141,6 141,6 30
– – 4,5
– – 8,3
1,5 1,5 1,5
0,6 0,6 0,3
114 114 119
142 142 142
1,5 1,5 1,5
0,6 0,6 0,3
110
170 170 170
54 54 72
71 000 83 000 92 300
193 000 220 000 335 000
6 300 7 350 10 400
5 100 4 600 4 000
6 400 5 700 4 800
3,9 3,9 5,05
BTM 110 A/DB BTM 110 B/DB 234422 BM1
110
137,9 137,9 150
155,2 155,2 36
– – 4,5
– – 8,3
2 2 2
1 1 0,6
127 127 132
160 160 161
2 2 2
1 1 0,6
120
180 180 180
54 54 72
73 500 86 500 93 600
212 000 240 000 360 000
6 500 7 200 10 800
4 800 4 300 3 800
6 000 5 300 4 500
4,18 4,18 5,7
BTM 120 A/DB BTM 120 B/DB 234424 TN9
120
147,7 147,7 160
170,3 170,3 36
– – 4,5
– – 8,3
2 2 2
1 1 0,6
137 137 142
170 170 171
2 2 2
1 1 0,6
130
200 200 200
63 63 84
90 000 265 000 108 000 300 000 117 000 455 000
7 700 8 800 13 200
4 500 3 800 3 400
5 600 4 800 4 000
6,27 6,27 8,15
BTM 130 A/DB BTM 130 B/DB 234426 TN9
130
162,6 162,6 177
187,7 187,7 42
– – 6
– – 11,1
2 2 2
1 1 0,6
150 150 156
190 190 190
2 2 2
1 1 0,6
140
210
84
117 000 475 000
13 200
3 200
3 800
8,65
234428 BM1
140
187
42
6
11,1
2,1
0,6
166
200
2
0,6
150
225
90
140 000 570 000
15 300
3 000
3 600
10,5
234430 BM1
150
200
45
7,5
13,9
2,1
0,6
178
213
2
0,6
160
240
96
156 000 640 000
16 600
2 800
3 400
14
234432 BM1
160
212
48
7,5
13,9
2,1
0,6
190
227
2
0,6
170
260
108
195 000 780 000
19 600
2 400
3 000
17,5
234434 BM1
170
230
54
7,5
13,9
2,1
0,6
204
246
2
0,6
180
280
120
225 000 915 000
22 400
2 000
2 600
23
234436 BM1
180
248
60
9
16,7
2,1
0,6
214
264
2
0,6
190
290
120
225 000 950 000
22 800
2 000
2 600
24
234438 BM1
190
258
60
9
16,7
2,1
0,6
224
274
2
0,6
200
310
132
265 000 1 100 000
25 500
1 900
2 400
31
234440 BM1
200
274
66
9
16,7
2,1
0,6
236
292
2
0,6
228
229
Hybrid double direction angular contact ball bearings d 60 – 130 mm
r4 r1
rb
r3
ra
r2
D1
d1
Da
da
H BTM – B
Principal dimensions d
D
Basic load ratings dynamic static H
mm
C
C0
N
4
BTM – A
Fatigue load limit Pu
Speed ratings Lubrication grease oil spot
N
r/min
Mass
Designation
Dimensions
d
kg
–
d1 ≈
Abutment and fillet dimensions
C, D1
r1, 2 min
r3, 4 min
mm
da min
Da min
ra max
rb max
mm
60
95 95
33 33
26 500 31 000
62 000 71 000
2 500 2 800
11 100 10 000
14 300 12 700
0,72 0,72
BTM 60 A/HCDB BTM 60 B/HCDB
60
75,9 75,9
89 89
1,1 1,1
0,6 0,6
70 70
90 90
1 1
0,6 0,6
65
100 100
33 33
27 500 32 500
68 000 76 500
2 600 2 900
10 500 9 400
13 500 12 000
0,77 0,77
BTM 65 A/HCDB BTM 65 B/HCDB
65
80,9 80,9
94,3 94,3
1,1 1,1
0,6 0,6
75 75
95 95
1 1
0,6 0,6
70
110 110
36 36
33 500 40 000
83 000 95 000
3 150 3 600
9 500 8 600
12 300 10 900
1,04 1,04
BTM 70 A/HCDB BTM 70 B/HCDB
70
88,6 88,6
103,6 103,6
1,1 1,1
0,6 0,6
82 82
105 105
1 1
0,6 0,6
80
125 125
40,5 40,5
41 500 49 000
104 000 120 000
3 900 4 400
8 400 7 600
10 800 9 600
1,48 1,48
BTM 80 A/HCDB BTM 80 B/HCDB
80
100,8 100,8
118,2 118,2
1,1 1,1
0,6 0,6
93 93
117 117
1 1
0,6 0,6
85
130 130
40,5 40,5
41 500 50 000
110 000 125 000
3 900 4 500
7 200 7 200
10 300 9 000
1,58 1,58
BTM 85 A/HCDB BTM 85 B/HCDB
85
105,8 105,8
123,2 123,2
1,1 1,1
0,6 0,6
98 98
124 124
1 1
0,6 0,6
90
140 140
45 45
49 000 57 000
125 000 143 000
4 470 5 100
7 600 6 700
9 600 8 400
2,08 2,08
BTM 90 A/HCDB BTM 90 B/HCDB
90
113 113
132 132
1,5 1,5
0,6 0,6
104 104
131 131
1 1
0,6 0,6
100
150 150
45 45
51 000 61 000
140 000 163 000
4 740 5 400
7 200 6 400
9 000 8 000
2,29 2,29
BTM 100 A/HCDB BTM 100 B/HCDB
100
123 123
141,6 141,6
1,5 1,5
0,6 0,6
114 114
141 141
1 1
0,6 0,6
110
170 170
54 54
71 000 83 000
193 000 220 000
6 300 7 350
6 200 5 500
7 700 6 800
3,64 3,64
BTM 110 A/HCDB BTM 110 B/HCDB
110
137,9 137,9
155,2 155,2
2 2
1 1
127 127
160 160
1,5 1,5
1 1
120
180 180
54 54
73 500 86 500
212 000 240 000
6 500 7 200
5 800 5 200
7 200 6 400
3,90 3,90
BTM 120 A/HCDB BTM 120 B/HCDB
120
147,7 147,7
170,3 170,3
2 2
1 1
137 137
171 171
1,5 1,5
1 1
130
200 200
63 63
90 000 265 000 108 000 300 000
7 700 8 800
5 400 4 600
6 700 5 800
5,87 5,87
BTM 130 A/HCDB BTM 130 B/HCDB
130
162,6 162,6
187,7 187,7
2 2
1 1
150 150
190 190
1,5 1,5
1 1
230
231
Single direction angular contact thrust ball bearings (“ball screw support bearings”) Contents
Single direction angular contact thrust ball bearings (“ball screw support bearings”) Bearings for universal matching Matched bearing sets Cartridge units General bearing data Preload Axial stiffness Friction torque Cages Speed ratings Lubrication Design of associated components Load carrying capacity of bearing sets Equivalent dynamic bearing load Equivalent static bearing load Designation system
234 236 236 239 240 241 242 243 243 244 244 245 247 248 248 249
Product tables Single direction angular contact thrust ball bearings Cartridge units with flanged housing
251 252 254
233
5
5 Single direction angular contact thrust ball bearings
Single direction angular contact thrust ball bearings (“ball screw support bearings”) SKF single direction angular contact thrust ball bearings have been developed especially for the support of ball and roller screws in machine tools, but are also used successfully for other applications where high axial rigidity and running accuracy is needed. They are of non-separable design and incorporate a large number of balls, have a particularly close conformity between balls and raceways, and a contact angle of 60°.
For best performance under extreme (shock-) loads, speeds, accelerations, and/or temperatures the bearings have a special blending of the raceway-shoulder transition, a light and robust cage design, and a special heat treatment for dimensional stabilisation. The special stabilisation for bore diameters larger than 20 mm ensures constant preload/stiffness over the whole application lifetime, and also at high temperature. SKF single direction angular contact thrust ball bearings are available in three metric dimension series: the series BSA 2
and BSA 3 having boundary dimensions conform to ISO 15:1998 (although this standard applies to radial bearings) and the series BSD (➔ fig 1 ). When the load carrying capacity of a single bearing is inadequate and/or when the bearing arrangement is required to take up axial loads acting in both directions these bearings can be supplied as “bearings for universal matching” single, or in matched sets. To further simplify mounting, complete ready-to-mount pre-greased cartridge units incorporating matched bearing sets in a flanged housing are supplied on request.
These bearings are characterised by high axial load ratings, ● superior axial stiffness, ● excellent running accuracy, especially in axial direction, ● speed and acceleration capability, and ● low frictional torque.
5
●
Different designs of SKF high-precision single direction angular contact thrust ball bearings Fig
Series BSA 2
234
Series BSA 3
1
Series BSD
235
5 Single direction angular contact thrust ball bearings
Bearings for universal matching Universally matchable single direction angular contact thrust ball bearings are adjusted during manufacturing to be mounted immediately adjacent to each other in a back-to-back, face-to-face, or tandem arrangement as desired. When arranged back-to-back or face-to-face, the predetermined value of the preload will be attained, requiring no subsequent adjustment. Bearings for universal matching can be supplied in two basic executions: single universal bearings for mounting in any combination, or duplex sets. Single bearings of ‘universal’ design are identified by the designation suffix G, which is followed by the letter A or B indicating the preload level, e.g. BSD 2047 CGA. When ordering these bearings, the number of single bearings required must be stated, not the number of sets. Universally matchable bearings may be useful in reducing stock holding and improving availability. Alternatively, duplex sets of bearings for universal matching can be chosen. They are identified by the suffix DGA or DGB, where A stands for light and B for heavy preload. The term ‘matched’ refers to matching of the bore and outside diameter which, in a set, at most differ by half the permissible diameter tolerance.
Matched bearing sets SKF single direction angular contact thrust ball bearings can be supplied in matched sets of two, three or four bearings. The bearing sets are matched during production so that when mounted immediately adjacent to each other, the predetermined preload value and/or an even load distribution among the rows will be attained. Bore and outside diameters of the bearings in a set at most differ by half the permissible diameter tolerance. When bearings are arranged back-to-back, the load lines diverge towards the bearing axis. Axial loads acting in both directions can be accommodated, but supported by one bearing or bearing pair only. This arrangement has a relatively high tilting stiffness and tilting moments can be taken up. In face-to-face arrangements the load lines converge towards the bearing axis. Again axial loads acting in both directions can be supported but only by one bearing or bearing pair at a time. This arrangement is less rigid than a back-to-back one with respect to tilting, but allows accommodating higher misalignments. In tandem arrangements the load lines of the bearings are parallel to each other. The bearing set can accommodate thrust load in one direction only, and is generally adjusted against another bearing or bearing pair. Arrangements of three or four bearings, of which two or three are in tandem, are usually adopted when higher load capacity or higher stiffness are required in the application. The most common arrangements are shown in fig 2 page 237.
Fig
Tandem arrangement Designation suffix DT
Face-to-face arrangement Designation suffix DF
Combination of tandem and back-to-back arrangement Designation suffix TBT
2
Back-to-back arrangement Designation suffix DB
Combination of tandem and face-to-face arrangement Designation suffix TFT
Combination of tandem and back-to-back arrangement Designation suffix QBC
Combination of tandem and face-to-face arrangement Designation suffix QFC
Combination of tandem and face-to-face arrangement Designation suffix QFT
Combination of tandem and back-to-back arrangement Designation suffix QBT
Tandem arrangement Designation suffix TT
5
Tandem arrangement Designation suffix QT
236
237
5 Single direction angular contact thrust ball bearings Marking of single bearings The bearing rings carry several markings for identification purposes. Each bearing is marked with the complete bearing designation. An asterisk (*) on the side face of inner and outer rings marks the position of the greatest out-of-round, i.e. where the greatest wall thickness between the base of the raceway groove and the bore or the outside diameter surface has been found (➔ fig 3 ). To facilitate the selection of the actual bore and outside diameter in order to obtain the desired fits after mounting, the actual deviation of the inner bore diameter and outside diameter from nominal are marked on the inner ring/outer ring respectively (just beside the asterisk).
Marking of bearing sets In addition to the markings of single bearings, bearings sets carry a “V”-shaped marking on the outside diameter of the bearings in order to facilitate proper mounting (➔ fig 4 ). If the bearing set is to perform correctly, the bearings must be mounted in the order indicated by the V-marking. The V-marking is always applied in relation with the position of the greatest out-of-round of outer ring and it also gives the direction in which the axial load should act on the inner ring(s). For bearing sets that can accommodate axial loads in both directions, the ‘V’-point gives the direction of the greater axial load. For each bearing of a matched set the same serial number is shown on the face of the outer ring.
Cartridge units To simplify and speed-up mounting, complete cartridge units incorporating matched sets of four single direction angular contact thrust ball bearings in a flanged housing are supplied on request. These units are characterised by the following features: ● ready to mount ● with a flange so that the units can be simply bolted to the machine frame ● sealed ● pre-lubricated with a special grease for long grease life and good anti-brinelling properties ● extremely stiff design of carbon steel housing.
5
Cartridge units are marked on the side face with their complete designation and SKF trademark.
Bearings for universal matching: example of marking of a single bearing
Example of marking of a bearing set Fig
3
Fig
4
SKF
*
Y
08
B
62
*
Y
B S A 2 0 6 C/ Q B T
B SA 2 06 C G A
-2
-2
*
*
-3
-3
SKF
AUST
RI A
AUST
RI A
238
239
5 Single direction angular contact thrust ball bearings
General bearing data Dimensions The boundary dimensions of series BSA 2 and BSA 3 conform to ISO 15:1998, Dimension Series 02 and 03 respectively, although this standard only applies to radial ball bearings. The boundary dimensions of the metric series BSD, and the cartridge units do not conform to any national or international standard, but have been widely accepted on the market for many years.
Tolerances SKF single direction angular contact thrust ball bearings are manufactured as standard according the tolerances shown in Table 1 . These values correspond to the ISO 492:2002-tolerance class 2 specifications, although the standards only apply to radial bearings. The inner and outer ring axial runout conform to ISO 492:2002-tolerance class 2. The values quoted refer to single bearings. For matched sets that are correctly mounted on accurately machined seating, the axial runout generally does not exceed 2,5 microns.
Preload SKF single direction angular contact thrust ball bearings are produced with two preload classes as standard: light (class A) and heavy (class B). Preload values apply both to single bearings and cartridge units. Axial preload values for sets of two bearings paired either back-to-back or face-to-face (DB or DF) are shown in Table 2 .
Matched sets incorporating more than two bearings (i.e. sets of three and four bearings) have higher preloads. Preload values for such sets can be obtained by multiplying the values in the preload table (➔ Table 2 ) by the factors stated in Table 3 page 242.
Preload in unmounted condition, friction torque and axial stiffness for single direction angular contact thrust ball bearings, series BSA and BSD Table Bearing designation
Axial preload Class A
B
N
Class 4 tolerances for single direction angular contact thrust ball bearings Table Inner ring d over
incl.
∆ds high
low
∆Ts high
low
Sia max
mm
mm
µm
µm
µm
µm
µm
10 18 30 50
18 30 50 80
0 0 0 0
−4 −5 −6 −7
0 0 0 0
−80 −120 −120 −150
1,5 2,5 2,5 2,5
D over
incl.
∆Ds high
low
Sea max
mm
mm
µm
µm
µm
18 30 50 80
30 50 80 120
0 0 0 0
−5 −6 −7 −8
2,5 2,5 4 5
Outer ring
240
1
Axial stiffness Preload A
2
5
Friction torque B
N/µm
A
B
Nm
BSA 201 C BSA 202 C BSA 203 C BSA 204 C BSA 205 C BSA 206 C BSA 207 C
650 775 1 040 1 480 1 580 2 250 2 950
1 300 1 550 2 080 2 960 3 160 4 500 5 900
350 415 535 660 730 925 1 090
455 535 700 860 935 1 180 1 390
0,016 0,023 0,045 0,056 0,077 0,132 0,202
0,029 0,040 0,080 0,101 0,132 0,224 0,345
BSA 305 C BSA 306 C BSA 307 C BSA 308 C
2 400 3 300 4 500 5 000
4 800 6 600 9 000 10 000
905 1 025 1 200 1 350
1 155 1 310 1 530 1 720
0,120 0,194 0,289 0,387
0,214 0,346 0,523 0,679
BSD 2047 C BSD 2562 C BSD 3062 C BSD 3572 C BSD 4072 C BSD 4090 C BSD 4575 C BSD 45100 C BSD 50100 C BSD 55100 C BSD 55120 C BSD 60120 C
1 480 2 400 2 250 2 950 2 950 5 000 2 900 6 500 6 500 6 500 7 900 7 900
2 960 4 800 4 500 5 900 5 900 10 000 5 800 13 000 13 000 13 000 15 800 15 800
660 905 925 1 090 1 090 1 350 1 185 1 535 1 535 1 535 1 770 1 770
860 1 155 1 180 1 390 1 390 1 720 1 515 1 965 1 965 1 965 2 260 2 260
0,056 0,120 0,132 0,202 0,202 0,387 0,256 0,548 0,548 0,548 0,800 0,800
0,101 0,214 0,224 0,345 0,345 0,679 0,414 0,971 0,971 0,971 1,400 1,400
241
5 Single direction angular contact thrust ball bearings Preload values refer to unmounted bearings, i.e. when the bearing rings are free to expand. Actual preloads will be higher when bearings are mounted with tight shaft/housing fits. Bearings with a special preload can be supplied as well.
Preload factor for single direction angular contact thrust ball bearings Table Bearing arrangement in a set
Preload factor
TBT or TFT QBT or QFT QBC or QFC
1,36 1,57 2,00
Axial stiffness
Friction torque
Cages
Single direction angular contact thrust ball bearings have been designed for superior axial rigidity. Stiffness values are given in Table 2 page 241 and refer to sets of two bearings matched either DB or DF, before mounting. Stiffness values for other bearing arrangements can be obtained by multiplying the values quoted in Table 2 by the factors in Table 4 . Higher stiffness may be obtained by using sets with still higher preloads, although this is not advisable as too high a preload will generate a temperature rise. Please consult the SKF application engineering service for more details.
The bearings of series BSD and BSA have been designed for low friction torque. Friction torque is directly influenced by the amount of preload actually acting on the bearing sets, the higher the preload value, the higher the friction torque. Guideline values for friction torque are given in Table 2 page 241, based on operating conditions with light and heavy preload, and at low speed. The starting torque will be approximately twice as high as the operating running torque. The torque values in the table apply to sets of two bearings matched back-to-back or face-toface. Torque values for other bearing arrangements can be obtained by multiplying the values shown in Table 2 by the factors given in Table 4 .
SKF single direction angular contact thrust ball bearings are built to withstand rapid speed changes and high rotational accelerations. Under such conditions the cage has to withstand high inertia forces. Therefore, a special ball-centred cage of injection moulded, glass fibre reinforced polyamide 6,6 is applied. Generally these cages may be used at temperatures up to +120°C although short periods at higher temperature will not have a detrimental effect - provided they are followed by long periods at lower temperatures. The lubricants employed with rolling bearings generally do not have any detrimental effect on cage characteristics, with the exception of some synthetic oils, greases based on such oils and some lubricants containing large proportions of EP additives, especially at high temperatures.
3
Stiffness and friction factor for single direction angular contact thrust ball bearings Table Bearing arrangement in a set
Stiffness factor for low axial for high axial bearing load bearing load1)
Friction factor
TBT or TFT QBT or QFT QBC or QFC
1,45 1,79 2,00
1,35 1,55 2,00
1)
1,64 2,24 2,00
Speed reduction factor for sets of single direction angular contact thrust ball bearings 4
Table Bearing arrangement
Bearing design BSA 2, BSA 3 and BSD Preload A B
Set of 2 bearings paired in tandem
0,8
0,4
Set of 2 bearings paired back-to-back or face-to-face
0,8
0,4
Set of 3 bearings
0,65
0,3
Set of 4 bearings
0,5
0,25
5
Guideline values under the assumption of a high external axial load acting in the direction of the highest load capacity of the bearing set (in accordance with DIN 628-6).
242
243
5
5 Single direction angular contact thrust ball bearings
Lubrication
The speed rating values quoted in the product tables are guideline values for single bearings with light preloads under light loads. For bearing sets the values should be reduced according to the number of bearings in the set and their preload, see Table 5 page 243. For grease lubrication the speed rating values in the product tables can be used directly. For other lubrication methods certain factors have to be taken into account, see Table 6 . The speed ratings quoted for cartridge units already take into account the number of bearings with which the cartridge is filled.
Single direction angular contact thrust ball bearings can be lubricated with either grease or oil. Generally, grease lubrication is preferred as bearing design can be simple, sealing arrangements uncomplicated and maintenance requirements minimised. Good quality, high grade greases with EP-additives and good anti-brinelling properties with an operating temperature range of −30 to +120°C are recommended. As a rule, a normal filling grade (25 % to 35 % of the free space in the bearings) is recommended for a long-lasting lubrication. If the bearings are running at very high speeds, lower filling rates (e.g. 15 %) will give lower temperatures and better performance. The actual quantities are given in the Table 2 page 65 in the Chapter: Principles of bearing selection and application, section Lubrication and Maintenance.
Speed reduction factor for different lubrication methods
Reduction factor
Oil bath
these bearing arrangements can only be achieved, however, if the accuracy of the associated components corresponds to bearing accuracy. Deviations in dimensions and geometrical form must therefore be as small as possible. Recommended tolerances for the bearing seatings on the spindle, and in the housing bore for bearings and cartridges will be found in the Tables 7 and fig 5 , Tables 8 , 9 and fig 6 and 7 page 246.
The single direction angular contact thrust ball bearings are manufactured to a high degree of accuracy and are primarily intended for the support of precision ball screws in numerically controlled machine tools, and in robots. The high demands in respect of running accuracy placed on
5
Accuracy of form for shafts
Accuracy of shaft seatings Table
Lubrication method
Design of associated components
6
Table
7
Tolerance h4
Tolerance grades Cylindricity Runout
0,3 – 0,4
Nominal bore diameter d over incl.
high low
IT2 t11)
IT2 t21)
Oil mist
0,95
mm
µm
µm
µm
Oil jet
Generally > 1 but depends very much on oil type, oil supply rate, oil inlet temperature, oil drainage efficiency, etc. Please consult the SKF application engineering service for details.
10 18 30 50
2 2,5 2,5 3
2 2,5 2,5 3
18 30 50 80
0 0 0 0
–5 –6 –7 –8
Fig
t2
A
5
A
d
Speed ratings
t1 1)
244
See fig 5
245
5 Single direction angular contact thrust ball bearings Accuracy of form for housings
➤
Fig
t2
A
6
A
The values given in the bearing tables for the basic dynamic and static load ratings apply to single bearings. For sets of bearings it must be remembered that each bearing can only support axial load acting in one direction. It is therefore necessary to calculate bearing life etc. using only the number of bearings actually supporting the thrust load in a given direction, i.e. for a pair of bearings arranged back-to-back, only one bearing will carry the load in a given direction. Appropriate guidance for calculating the basic load ratings of bearings in matched sets is given in Table 10 .
Accuracy of housing bore seatings for bearings Table
8
Tolerance H5
Tolerance grades Cylindricity Runout
high low
IT3 t11)
IT3 t21)
mm
µm
µm
µm
2 3 4
4 5 6
– 50 80
50 80 120
0 0 0
+11 +13 +15
D
Nominal bore diameter d over incl.
Load carrying capacity of bearing sets
5 t1
1)
See fig 6
Dynamic and static load ratings for ball screw support bearing sets Accuracy of form for housings for cartridge units
➤
Fig
t2
A
Tolerance H6
Tolerance grades Runout
high low
IT3 t11)
mm
µm
µm
50 80 120
1)
80 120 150
0 0 0
+19 +22 +25
5 6 8
Set
Load direction
Arrangement
Dynamic
Static
X
Y
2
DB DF DT
⇐ ⇐ ⇒
〈〉 〉〈 〈〈
C C 1,63 C
C0 C0 2 C0
1,9 1,9 –
0,55 0,55 –
3
TBT TBT TFT TFT TT
⇐ ⇒ ⇒ ⇐ ⇒
〈 〉〉 〈 〉〉 〉 〈〈 〉 〈〈 〈〈〈
1,63 C C 1,63 C C 2,16 C
2 C0 C0 2 C0 C0 3 C0
2,32 1,43 2,32 1,43 –
0,35 0,76 0,35 0,76 –
4
QBT QBT QFT QFT QBC QFC QT
⇒ ⇐ ⇒ ⇐ ⇒ or ⇐ ⇒ or ⇐ ⇒
〈〈〈 〉 〈〈〈 〉 〉 〈〈〈 〉 〈〈〈 〈〈 〉〉 〉〉 〈〈 〈〈〈〈
2,16 C C 2,16 C C 1,63 C 1,63 C 2,64 C
3 C0 C0 3 C0 C0 2 C0 2 C0 4 C0
2,52 1,17 2,52 1,17 1,9 1,9 –
0,26 0,88 0,26 0,88 0,55 0,55 –
9
C
Nominal bore diameter d over incl.
Bearings in a set
A
Accuracy of housing bore seatings for cartridge units Table
Table 10
7
See fig 7
246
247
5 Single direction angular contact thrust ball bearings
Equivalent dynamic bearing load The equivalent dynamic bearing load for single bearings and any configuration of bearings in a set can be calculated – separately for the two directions of axial load – from P = XFr + YFa for Fa/Fr 2,17 P = 0,92 Fr + Fa for Fa/Fr > 2,17 where P = equivalent dynamic load acting on bearing or bearing set, N Fr = radial component of actual load acting on bearing or bearing set, N Fa = axial component of actual load acting on bearing or bearing set, N X = radial load factor, see Table 10 page 247 Y = axial load factor, see Table 10 Note that when calculating the axial load component Fa the (non-linear) influence of internal bearing preload acting within the bearing set must be taken into account.
248
Equivalent static bearing load
Designation system
For bearing sets with bearings arranged back-to-back or face-to-face, the equivalent static load can be determined – separately for each direction of axial load – from
For series BSA 2 and BSA 3 conform to ISO 15:1998 and metric series BSD the complete designation of a single bearing identifies the series itself and the bore diameter. The designation of the series BSD bearings includes both bore and outside diameter. For bearing sets, additional suffixes specify the number of bearings in a set, their arrangement in the set and preload class. Details of the designation system are given in Table 11 page 250.
P0 = 4Fr + Fa where P0 = equivalent static load acting on bearing or bearing set, N Fr = radial component of maximum static load acting on bearing or bearing set, N Fa = axial component of maximum static load acting on bearing or bearing set, N
The designation of cartridge units identifies bore diameter, number of bearings and their arrangement in a set, as well as the preload class. In cases where the application requires special preload, SKF supplies single bearings, bearing sets or cartridge units with appropriate preload values. An additional suffix G followed by the actual preload value expressed in daN is then shown in the designation (e.g. BSA 206 C/DBG360, matched set of two bearings arranged back-to-back with an 3600 N special preload).
5
The equation for the equivalent static load is also valid for single bearings and bearings arranged in tandem, provided the ratio Fa /Fr does not exceed 0,25. Satisfactory but less accurate values are obtained when Fa /Fr is between 0,25 and 0,4.
249
5 Single direction angular contact thrust ball bearings
Product tables Designations of single direction angular contact thrust ball bearings for precision ball screws Table 11 Basic designation BS
A
Ball Screw support bearings
ISO 15 series
Metric series
Dimension series 2 ISO 15 Diameter Series 2 3 ISO 15 Diameter Series 3 Bore diameter 01 02 03 04 (×5) | 15 (×5)
12 mm bore diameter 15 mm bore diameter 17 mm bore diameter 20 mm bore diameter
Bore diameter, mm Outside diameter, mm
60 degrees Special internal design
Number of bearings in set D T Q
Two bearings Three bearings Four bearings
Bearing arrangement in matched set B F T BT FT BC FC G
Back-to-back Face-to-face Tandem Back-to-back/tandem Face-to-face/tandem Back-to-back of pairs in tandem Face-to-face of pairs in tandem For universal matching
Preload A B G..
Light preload Heavy preload Special preload (value in daN e.g. G240)
250
5
Bore diameter 20 47
75 mm bore diameter
Contact angle – Internal design C
EXAMPLES
D
Dimension series Not standardised –
BSA 204 C/DBA BSD 2047 C/QBCA
251
Single direction angular contact thrust ball bearings d 12 – 75 mm H r1 r1
r2
r2
r2
r2
ra
ra
r1 r1
D D2 d1
d
Da da
Da da
d 2 D1
a
Principal dimensions d
D
Basic load ratings dynamic static H
mm
C
C0
N
Fatigue load limit Pu
Maximum axial load
Speed ratings Lubrication grease oil spot
N
N
r/min
Mass
Designation
Dimensions
d
kg
–
mm
d1 ≈
Abutment and fillet dimensions
d2 ≈
D1 ≈
D2 ≈
r1, 2 min
a
da min
Da max
ra max
mm
12
32
10
11 400
18 000
670
7 250
12 000
16 000
0,024
BSA 201 C
12
18,0
22,3
21,7
27,0
0,6
24
18
29
0,6
15
35
11
12 200
20 400
765
8 500
11 000
15 000
0,054
BSA 202 C
15
21,0
25,3
24,8
30,0
0,6
27
21
31,9
0,6
17
40
12
18 300
37 500
1 370
13 000
9 700
13 000
0,078
BSA 203 C
17
24,4
29,3
28,6
34,8
0,6
31
21,7
36,5
0,6
20
47 47
14 15
24 000 24 000
52 000 52 000
1 930 1 930
19 500 19 500
8 200 8 200
11 000 11 000
0,13 0,13
BSA 204 C BSD 2047 C
20
29,2 29,2
34,8 34,8
34,2 34,2
41,1 41,1
1 1
36 37
26,4 26,4
42,1 42,1
1 1
25
52 62 62
15 17 15
24 500 36 500 36 500
56 000 86 500 86 500
2 080 3 200 3 200
20 800 36 000 36 000
7 500 6 700 7 200
10 000 9 000 9 600
0,15 0,27 0,25
BSA 205 C BSA 305 C BSD 2562 C
25
33,2 39,4 39,4
38,8 46,3 46,3
38,2 45,6 45,6
45,1 54,2 54,2
1 1,1 1,1
40 48 47
31 33,9 33,9
47,2 55,3 55,3
1 1 1
30
62 62 72
16 15 19
32 000 32 000 49 000
80 000 80 000 114 000
3 000 3 000 4 250
31 500 31 500 52 800
6 900 7 200 5 900
9 300 9 600 7 900
0,24 0,22 0,41
BSA 206 C BSD 3062 C BSA 306 C
30
41,0 41,0 43,3
47,3 47,3 51,8
46,6 46,6 51,1
54,4 54,4 61,2
1 1 1,1
48 48 54
36,8 36,8 40,1
56,7 56,7 64,6
1 1 1
35
72 72
15 17
39 000 39 000
104 000 104 000
3 900 3 900
42 750 42 750
6 600 6 300
8 900 8 400
0,3 0,34
BSD 3572 C BSA 207 C
35
48,4 48,4
55,3 55,3
54,6 54,6
63,1 63,1
1,1 1,1
55 56
43,4 43,4
65,3 65,3
1 1
40
72 90 90
15 23 20
39 000 69 500 69 500
104 000 183 000 183 000
3 900 6 800 6 800
42 750 78 200 78 200
6 600 4 800 5 100
8 900 6 400 6 900
0,27 0,77 0,68
BSD 4072 C BSA 308 C BSD 4090 C
40
48,4 56,9 56,9
55,3 66,8 66,8
54,6 66,1 66,1
63,1 77,8 77,8
1,1 1,5 1,5
55 69 69
47,4 51,5 51,5
65,3 81,4 81,4
1 1,5 1,5
45
75 100
15 20
35 500 88 000
104 000 240 000
3 900 8 800
40 200 107 400
6 500 4 800
8 700 6 500
0,27 0,83
BSD 4575 C BSD 45100 C
45
67,3 65,5
59,6 76,8
60,4 76,1
54,0 89,4
1,1 1,5
59 76
52,4 58,1
68,6 90,5
1 1,5
50
100
20
88 000
240 000
8 800
107 400
4 800
6 500
0,77
BSD 50100 C
50
65,5
76,8
76,1
89,4
1,5
76
62,4
90,5
1,5
55
100 120
20 20
88 000 240 000 112 000 320 000
8 800 11 800
107 400 130 000
4 800 4 300
6 500 5 800
0,74 1,15
BSD 55100 C BSD 55120 C
55
65,5 78,7
76,8 91,4
76,1 90,6
89,4 105,6
1,5 1
76 89
65,5 86,5
90,5 111,5
1,5 1
60
120 110
20 22
112 000 320 000 78 000 245 000
11 800 9 000
130 000 90 000
4 300 4 200
5 800 5 600
1,09 0,95
BSD 60120 C BSA 212 C
60
78,7 77,4
91,4 87,4
90,6 86,6
105,6 98,3
1 1,5
89 86
72,5 70,9
111,5 101,8
1 1,5
75
130
25
81 500
10 400
100 000
3 600
4 700
1,6
BSA 215 C
75
89,4
99,4
98,6
110,3
1,5
98
85,3
122,3
1,5
252
280 000
5
253
Cartridge units with flanged housing d 20 – 55 mm A
30°
A1 A3
A2
N
J2
D1
Da
N1
J1
da D3 D2 J H
45°
Dimensions
da
A
A1
Mass
A2
A3
D1
D2
D3
Da
H
J
J1
J2
N
Designation
Basic load ratings dynamic static C
N1
mm
kg
–
Maximum axial load
Axial rigidity Preload class A B
Friction torque Preload class A B
Speed rating Preload class A B
N
N/µm
Nm
r/min
C0
N
32 32
6,6 6,6
2,7 2,7
1,75 1,75
FBSA 204/QBCA FBSA 204/QFCA
FBSA 204/QBCA
39 000 39 000
104 000 104 000
39 000 39 000
1 320 1 320
1 720 1 720
0,112 0,112
0,202 0,202
4 100 4 100
1 800 1 800
120 102 60 120 102 60
44 44
9,2 9,2
4,3 4,3
3,5 3,5
FBSD 25/QBCA FBSD 25/QFCA
FBSD 25/QBCA
60 000 60 000
173 000 173 000
72 000 72 000
1 810 1 810
2 310 2 310
0,24 0,24
0,428 0,428
3 600 3 600
1 600 1 600
52 52
120 102 60 120 102 60
44 44
9,2 9,2
4,3 4,3
3,4 3,4
FBSD 30/QBCA FBSD 30/QFCA
FBSD 30/QBCA
52 000 52 000
160 000 160 000
63 000 63 000
1 850 1 850
2 360 2 360
0,26 0,26
0,448 0,448
3 600 3 600
1 600 1 600
45 45
59 59
130 113 65 130 113 65
49 49
9,2 9,2
4,3 4,3
4,25 4,25
FBSD 35/QBCA FBSD 35/QFCA
FBSD 35/QBCA
64 000 64 000
208 000 208 000
85 500 85 500
2 180 2 180
2 780 2 780
0,404 0,404
0,69 0,69
3 300 3 300
1 400 1 400
17 17
128 124 55 128 124 55
75 75
165 146 88 165 146 88
64 64
11,4 11,4
5,2 5,2
9,6 9,6
FBSD 40/QBCA FBSD 40/QFCA
FBSD 40/QBCA
114 000 114 000
366 000 366 000
156 400 156 400
2 700 2 700
3 440 3 440
0,774 0,774
1,358 1,358
2 600 2 600
1 100 1 100
43,5 43,5
17 17
128 124 70 128 124 70
82 82
165 146 97 165 146 97
64 64
11,4 11,4
6,2 6,2
9,35 9,35
FBSD 45/QBCA FBSD 45/QFCA
FBSD 45/QBCA
143 000 143 000
480 000 480 000
214 800 214 800
3 070 3 070
3 930 3 930
1,096 1,096
1,942 1,942
2 400 2 400
1 000 1 000
43,5 43,5
17 17
128 124 70 128 124 70
82 82
165 146 97 165 146 97
64 64
11,4 11,4
6,2 6,2
9,05 9,05
FBSD 50/QBCA FBSD 50/QFCA
FBSD 50/QBCA
143 000 143 000
480 000 480 000
214 800 214 800
3 070 3 070
3 930 3 930
1,096 1,096
1,942 1,942
2 400 2 400
1 000 1 000
20
77 77
74,26 72,74
32 32
13 13
64 64
60 60
26 26
37 37
90 90
25
82 82
80,26 78,74
32 32
15 15
88 88
80 80
38 38
52 52
30
82 82
80,26 78,74
32 32
15 15
88 88
80 80
38 38
35
82 82
80,26 78,74
32 32
15 15
98 98
90 90
40
106 104,26 106 102,74
43,5 43,5
45
106 104,26 106 102,74
50
106 104,26 106 102,74
254
Designation1)
5
76 76
43,8 43,8
255
Cartridge units with flanged housing d 55 – 60 mm A
30°
A1 A3
A2
N
J2
D1
Da
N1
J1
da D3 D2 J H
45°
Dimensions
da
A
A1
Mass
A2
A3
D1
D2
D3
Da
H
J
J1
J2
N
Designation1)
Designation
C
N1
mm
Basic load ratings dynamic static
kg
–
5
Maximum axial load
Axial rigidity Preload class A B
Friction torque Preload class A B
Speed rating Preload class A B
N
N/µm
Nm
r/min
C0
N
55
106 104,26 106 104,26
43,5 43,5
17 17
148 144 86 148 144 86
103 185 166 112,5 74 103 185 166 112,5 74
11,4 11,4
6,2 6,2
11,7 11,7
FBSD 55/QBCA FBSD 55/QFCA
FBSD 55/QBCA
183 000 183 000
640 000 640 000
260 000 260 000
3 540 3 540
4 520 4 520
1,6 1,6
2,8 2,8
2 150 2 150
900 900
60
106 104,26 106 104,26
43,5 43,5
17 17
148 144 86 148 144 86
103 185 166 112,5 74 103 185 166 112,5 74
11,4 11,4
6,2 6,2
11,4 11,4
FBSD 60/QBCA FBSD 60/QFCA
FBSD 60/QBCA
183 000 183 000
640 000 640 000
260 000 260 000
3 540 3 540
4 520 4 520
1,6 1,6
2,8 2,8
2 150 2 150
900 900
1)
The designations are given for units with lightly preloaded bearing sets (suffix A). To specificy a heavy preload the suffix should be changed to B. e.g. FBSD 204/QBCB
Please contact SKF as to availability.
256
257
Locking devices Contents
Locking devices
260
Lock nuts Two different designs General data
261 261 263
Product tables KMT precision lock nuts KMTA precision lock nuts
265 266 270
Stepped sleeves Two different designs General data
274 274 275
Dimension tables Stepped sleeves
279 279
259
6
6 Locking devices
Locking devices Locking devices for the axial location of high-precision bearings on the shaft must be made very accurately. Normal design lock nuts with locking washers are not entirely suitable for high-precision bearings because of the relatively large manufacturing tolerance for the thread and the abutment surfaces, which may lead to shaft deformation and alterations in the axis of rotation. They should provide even support for the inner ring around its whole circumference, preventing shaft deformation, particularly under conditions of heavy preload. They should also be simple to mount and dismount. To meet the high demands of machine tool applications, both technically and economically, SKF produces precision lock nuts, and also developed the stepped sleeve.
SKF lock nuts of the KMT and KMTA designs were developed for use with highprecision bearings and their dimensions were chosen to match. KMT and KMTA nuts have both locking pins and differ principally in their external form and also, in part, in the pitch of the thread. Stepped sleeves are pressure joints with two fitting surfaces, of slightly different diameters, arranged adjacent to each other. They enable bearing arrangements having high running accuracy to be produced. The sleeves are not supplied by SKF but recommendations regarding design and suitable dimensions are given in the relevant section (page 276).
Lock nuts Two different designs SKF manufactures two different types of precision lock nuts with locking pins: the KMT and the KMTA. Both enable bearings and other components to be simply and reliably located in the axial direction on shafts, with high accuracy. Their special design feature consists of three sintered steel locking-pins, which are equally spaced around the circumference. These pins are pressed against the shaft thread by grub screws with an internal hexagon and prevent the nut from turning. Mounting is easy and the design simple. Additional locking washers or slots in the shaft are not required. The locking pins and grub screws
The locking pins and grub screws are arranged at the same angle to the shaft as that of the thread flanks Fig
260
are arranged at the same angle to the shaft axis as that of the thread flanks. The ends of the pins are machined in a single operation with the nut thread and consequently also have a threaded profile. The nut is locked in position purely as a result of the friction between the locking pins and the shaft thread, and the adhesive friction between the flanks of the thread. Therefore, the locking pins are not subjected to the axial loads that act on the nut. When the nut is locked, the thread flanks are not relieved of loads axially and the nut is not deformed (➔ fig 1 ). Another advantage of the KMT and KMTA nuts is that they are adjustable. The three equally spaced locking pins enable the nut to be accurately positioned at right angles to the shaft, or they can be used to adjust for inaccuracies or deviations of other components that are to be located on the shaft. As the locking pins are not deformed, KMT and KMTA nuts retain their high precision irrespective of the number of times they are mounted and dismounted. An example of application of KMT lock nuts is shown in fig 4 page 262.
1
261
6
6 Locking devices KMT lock nuts
KMTA lock nuts
KMT lock nuts (➔ fig 2 ) are designed as slotted nuts. Up to and including size 15 they are also provided with two diametrically opposed flats to accept a spanner. They are particularly suitable for applications where simple assembly and reliable locking with high precision are required.
KMTA lock nuts (➔ fig 3 ) differ from the KMT nuts in their external form and in some cases in the thread that has a different pitch, but offer the same benefits. They have a smooth cylindrical outside surface and are intended for positions where space is limited. As the outside surface is cylindrical, the nut can also be used to form part of a gap-type seal. Holes around the circumference and in one side face facilitate mounting.
KMT design
KMTA design Fig
2
Fig
General data Tolerances The threads of KMT and KMTA nuts are made to tolerance 5H and conform to ISO 965-3:1998. The recommended tolerance for the mating thread on the shaft is 6g and conforms also to ISO 965-3:1998. Materials KMT and KMTA lock nuts are made of high-strength steel; their surfaces are phosphated and oiled. Sintered material is used for the locking pins. The grub screws conform to DIN 915:1980, strength class 45 H.
Mounting KMT lock nuts are very simple to mount. Slots are provided around the circumference and there are two diametrically opposed flats on all nuts up to and including size 15. Various types of spanners can be used depending on the application and nut size, including hook and impact spanners (➔ fig 5 ). Appropriate sizes of spanner and key (for the grub screws) are given in the product table. The KMTA lock nuts can be tightened using hook spanners with studs to engage the holes in the circumference. Alternatively a pin-type face spanner, or a tommy bar can be used. Appropriate hook spanners are given in the product table.
3
6
Mounting KMT and KMTA lock nuts using spanners or keys Fig
Fig
262
4
5
Application example
263
6 Locking devices To lock the KMT and KMTA nuts, the grub screws should first be gently tightened until the thread of the locking pin engages the shaft thread. The grub screws should then be firmly tightened alternately and evenly, until the recommended tightening torque quoted in the product tables is obtained. If it is necessary to correct for any misalignment between the abutment surfaces of the nut and adjacent component, the grub screw at the position of greatest deviation should first be loosened and the other two screws should be tightened to an equal degree. The loosened screw should then be retightened. If this correction for the misalignment is found to be inadequate, the procedure should be repeated until the desired accuracy has been achieved (➔ fig 6 ). This can be checked using a dial gauge, for example.
Dismounting It should be remembered when dismounting KMT and KMTA lock nuts that the locking pins will still firmly engage the shaft thread, even after the grub screws have been loosened. Light blows with a rubber hammer to the nut, in the vicinity of the grub screws will serve to loosen the pins. The nuts can then easily be unscrewed from the shaft thread.
Product tables
6
Correction of misalignment between the abutment of the nut and adjacent component Fig
264
6
265
KMT precision lock nuts
M
B 60°
d1
h
b
d4 d3 d2
Dimensions
G
d1
d2
d3
d4
B
b
h
M
mm
Axial load carrying capacity static
Grub screws Size Tightening torque max
Mass
Designation
Appropriate hook/impact spanner to DIN 1810
kN
–
Nm
kg
–
–
×0,75 M 10× ×1 M 12×
21 23
28 30
23 25
11 13
14 14
4 4
2 2
24 27
35 40
M5 M5
4,5 4,5
45 50
KMT 0 KMT 1
HN 2/3 HN 3
×1 M 15× ×1 M 17×
26 29
33 37
28 33
16 18
16 18
4 5
2 2
30 34
60 80
M5 M6
4,5 8
75 0,10
KMT 2 KMT 3
HN 4 HN 4
×1 M 20× ×1,5 M 25×
32 36
40 44
35 39
21 26
18 20
5 5
2 2
36 41
90 130
M6 M6
8 8
0,11 0,13
KMT 4 KMT 5
HN 5 HN 5
×1,5 M 30× ×1,5 M 35×
41 46
49 54
44 49
32 38
20 22
5 5
2 2
46 50
160 190
M6 M6
8 8
0,16 0,19
KMT 6 KMT 7
HN 6 HN 7
×1,5 M 40× ×1,5 M 45×
56 61
65 70
59 64
42 48
22 22
6 6
2,5 2,5
60 65
210 240
M6 M6
8 8
0,30 0,33
KMT 8 KMT 9
HN 8/9 HN 9/10
×1,5 M 50× ×2 M 55×
65 74
75 85
68 78
52 58
25 25
7 7
3 3
70 80
300 340
M6 M8
8 18
0,40 0,54
KMT 10 KMT 11
HN 10/11 HN 12/13
×2 M 60× ×2 M 65×
78 83
90 95
82 87
62 68
26 28
8 8
3,5 3,5
85 90
380 460
M8 M8
18 18
0,61 0,71
KMT 12 KMT 13
HN 13 HN 14
×2 M 70× ×2 M 75×
88 93
100 105
92 97
72 77
28 28
8 8
3,5 3,5
95 100
490 520
M8 M8
18 18
0,75 0,80
KMT 14 KMT 15
HN 15 HN 15/16
×2 M 80× ×2 M 85×
98 107
110 120
100 110
83 88
32 32
8 10
3,5 4
– –
620 650
M8 M 10
18 35
0,90 1,15
KMT 16 KMT 17
HN 16/17 HN 17/18
×2 M 90× ×2 M 95×
112 117
125 130
115 120
93 98
32 32
10 10
4 4
– –
680 710
M 10 M 10
35 35
1,20 1,25
KMT 18 KMT 19
HN 18/19 HN 19/20
×2 M 100× ×2 M 110×
122 132
135 145
125 134
103 112
32 32
10 10
4 4
– –
740 800
M 10 M 10
35 35
1,30 1,45
KMT 20 KMT 22
HN 20 HN 22
×2 M 120× ×2 M 130×
142 152
155 165
144 154
122 132
32 32
10 12
4 5
– –
860 920
M 10 M 10
35 35
1,60 1,70
KMT 24 KMT 26
TMFN 23-30 TMFN 23-30
266
6
267
KMT precision lock nuts
M
B 60°
d1
h
b
d4 d3 d2
Dimensions
G
d1
d2
d3
d4
B
b
h
M
mm
Axial load carrying capacity static
Grub screws Size Tightening torque max
Mass
Designation
Appropriate hook/impact spanner to DIN 1810
kN
–
Nm
kg
–
–
×2 M 140× ×2 M 150×
162 172
175 185
164 174
142 152
32 32
14 14
6 6
– –
980 1 040
M 10 M 10
35 35
1,80 1,95
KMT 28 KMT 30
TMFN 23-30 TMFN 23-30
×3 M 160× ×3 M 170×
182 192
195 205
184 194
162 172
32 32
14 14
6 6
– –
1 100 1 160
M 10 M 10
35 35
2,10 2,20
KMT 32 KMT 34
TMFN 30-40 TMFN 30-40
×3 M 180× ×3 M 190×
202 212
215 225
204 214
182 192
32 32
16 16
7 7
– –
1 220 1 280
M 10 M 10
35 35
2,30 2,40
KMT 36 KMT 38
TMFN 30-40 TMFN 30-40
×3 M 200×
222
235
224
202
32
18
8
–
1 340
M 10
35
2,50
KMT 40
TMFN 30-40
268
6
269
KMTA precision lock nuts
30° B
d4 d3 d2
J1 G
N1 N2 J2
Dimensions
G
d2 h11
d3
d4
B
J1
J2
N1
N2
mm
Axial load carrying capacity static
Grub screws Size Tightening torque
Mass
Designation
Appropriate hook spanner to DIN 1810 Form B
kN
–
Nm
kg
–
–
max
M 25×1,5 M 30×1,5
42 48
35 40
26 32
20 20
32,5 40,5
11 11
4,3 4,3
4 5
130 160
M6 M6
8 8
0,13 0,16
KMTA 5 KMTA 6
HN 5B HN 6B
M 35×1,5 M 40×1,5
53 58
47 52
38 42
20 22
45,5 50,5
11 12
4,3 4,3
5 5
190 210
M6 M6
8 8
0,19 0,23
KMTA 7 KMTA 8
HN 7B HN 8B
M 45×1,5 M 50×1,5
68 70
58 63
48 52
22 24
58 61,5
12 13
4,3 4,3
6 6
240 300
M6 M6
8 8
0,33 0,34
KMTA 9 KMTA 10
HN 9B HN 10B
M 55×1,5 M 60×1,5
75 84
70 75
58 62
24 24
66,5 74,5
13 13
4,3 5,3
6 6
340 380
M6 M8
8 18
0,37 0,49
KMTA 11 KMTA 12
HN 11B HN 12B
M 65×1,5 M 70×1,5
88 95
80 86
68 72
25 26
78,5 85
13 14
5,3 5,3
6 8
460 490
M8 M8
18 18
0,52 0,62
KMTA 13 KMTA 14
HN 13B HN 14B
M 75×1,5 M 80×2
100 110
91 97
77 83
26 30
88 95
13 16
6,4 6,4
8 8
520 620
M8 M8
18 18
0,66 1,00
KMTA 15 KMTA 16
HN 15B HN 16B
M 85×2 M 90×2
115 120
102 110
88 93
32 32
100 108
17 17
6,4 6,4
8 8
650 680
M 10 M 10
35 35
1,15 1,20
KMTA 17 KMTA 18
HN 17B HN 18B
M 95×2 M 100×2
125 130
114 120
98 103
32 32
113 118
17 17
6,4 6,4
8 8
710 740
M 10 M 10
35 35
1,25 1,30
KMTA 19 KMTA 20
HN 19B HN 20B
M 110×2 M 120×2
140 155
132 142
112 122
32 32
128 140
17 17
6,4 6,4
8 8
800 860
M 10 M 10
35 35
1,45 1,85
KMTA 22 KMTA 24
HN 22B HN 22B
M 130×3 M 140×3
165 180
156 166
132 142
32 32
153 165
17 17
6,4 6,4
8 10
920 980
M 10 M 10
35 35
2,00 2,45
KMTA 26 KMTA 28
B 155-165 B 180-195
M 150×3 M 160×3
190 205
180 190
152 162
32 32
175 185
17 17
6,4 8,4
10 10
1 040 1 100
M 10 M 10
35 35
2,60 3,15
KMTA 30 KMTA 32
B 180-195 B 205-220
270
6
271
KMTA precision lock nuts
30° B
d4 d3 d2
J1 G
N1 N2 J2
Dimensions
G
d2 h11
d3
d4
B
J1
J2
N1
N2
mm
Axial load carrying capacity static
Grub screws Size Tightening torque
Mass
Designation
Appropriate hook spanner to DIN 1810 Form B
kN
–
Nm
kg
–
–
max
M 170×3 M 180×3
215 230
205 215
172 182
32 32
195 210
17 17
8,4 8,4
10 10
1 160 1 220
M 10 M 10
35 35
3,30 3,90
KMTA 34 KMTA 36
B 205-220 B 230-245
M 190×3 M 200×3
240 245
225 237
192 202
32 32
224 229
17 17
8,4 8,4
10 10
1 280 1 340
M 10 M 10
35 35
4,10 3,85
KMTA 38 KMTA 40
B 230-245 B 230-245
272
6
273
6 Locking devices
Stepped sleeves Two different designs Stepped sleeves can either have a conventional sleeve form, or it may be ringshaped. Ring-shaped stepped sleeves are used, for example, where the sleeve is not only intended for the axial location of a bearing, it is also required to form part of a
labyrinth seal (➔ fig 1 ). The stepped design of the fitting surface was chosen principally to facilitate removal of the sleeve, but also to simplify alignment after mounting. If pressurised oil is injected through the sleeve to its seating, a directed axial force will be produced which causes the sleeve to slide from its seating as soon
as a sufficient thickness of oil film has been built up to separate the mating surface. For manufacturing reasons, or where relatively small axial forces are needed, the side of the sleeve having the smaller diameter surface can be given a loose fit on the shaft. In order to be able to use the oil injection method to dismount the sleeve, its bore at this side should be sealed by means of an O-ring. Stepped sleeves of this design exert only half of the axial retaining force of normal stepped sleeves. Compared to threaded locking nuts, stepped sleeves ensure a superior accuracy, provided they are manufactured to a high degree of accuracy. Conversely, stepped sleeves are expensive to manufacture, have to be designed properly, and require a proper mounting procedure. Stepped sleeves are generally used in very high-speed spindles, where the accuracy granted by conventional locking devices may not be sufficient.
General data Dimensions Stepped sleeves are not supplied by SKF and must be produced by the user. Recommended dimensions for stepped sleeves with and without an O-ring, and their seating are given in the product tables (pages 280 – 283). When dimensioning and manufacturing stepped sleeves, and the corresponding shaft seating, it is necessary to keep the difference in the degree of interference, between the two seats of fitting surfaces as small as possible. Experience has shown that dismounting is difficult if the difference is too large. The best approach is to start with the difference between diameters – the so-called step – as it is easier to keep within narrow tolerances for this diameter difference than for the diameter itself.
6 Stepped sleeves: design examples Fig
274
1
275
6 Locking devices Material
Axial load carrying capability
It is recommended that a steel, which can be heat-treated, with a yield point of at least 550 MPa should be used for the sleeve. Both sleeve and shaft should be hardened. The fitting surfaces in the sleeve and on the shaft should be ground.
The axial load carrying capacity of the joint can be calculated with the following formula:
where (➔ fig 2 ):
F = µπdLp F = axial load carrying capacity of the joint, N µ = friction coefficient L = length of the joint, mm The friction coefficient, µ, can be assumed to be 0,14. Assuming that both components are made of steel, the surface pressure between sleeve and shaft can be determined by the following equation: p=
(
206 000 ∆ 1 + c2i 1−c
2 i
+
1 + c 2e 1 − c 2e
)
p = surface pressure, MPa ∆ = interference fit, mm ci = d i /d ce = de /d d i = bore diameter of shaft, mm d = outside diameter of shaft, mm de = outside diameter of sleeve, mm For stepped sleeves on solid shafts or thickwalled hollow shafts, the following surface pressures are obtained in the sleeve/shaft contacts, if recommendations regarding dimensions and tolerances have been followed: ● approximately 40 MPa for diameters of approximately 30 mm ● approximately 35 MPa for diameters of approximately 100 mm ● approximately 22 MPa for diameters of approximately 200 mm
d
These produce retaining forces of approximately 300, 550 and 1 000 N per mm hub width respectively. Based on these values, it is possible to make a rough estimate of the retaining force that can be exerted by a mounted stepped sleeve. When designing the stepped sleeve, shock forces acting in an axial direction on the sleeve must also be taken into consideration. If necessary, a threaded nut which is lightly tightened, and which can also serve as a mounting aid, can be used to secure the sleeve. Thin-walled shafts may be subject to a relatively large diametrical deformation as the contact pressure must be high. Therefore, the sleeve for shafts of this kind should be made with a relief closest to the bearing, to avoid deformation of the bearing seating. The length of the relief should be 15 – 20 % of the shaft diameter.
6
Dimensions for the calculation of the axial load carrying capability Fig
2
L
de
276
d
di
277
6 Locking devices Mounting and dismounting To mount the stepped sleeve on the shaft, it should first be heated to a temperature higher than that of the shaft, by the number of degrees given in the dimension tables. It should then be pushed on its shaft seating. After it has cooled, oil should be injected between the mating surfaces and a suitable tool used to bring the sleeve into its correct position. In order to avoid localised stress peaks from occurring, the oil should be injected slowly and the oil pressure regulated. As the sleeve ‘swims’ on an oil film, any stresses produced during the shrinking on the sleeve will be relieved, and the components can be correctly positioned with respect to each other. After mounting has been completed the oil between the mating surfaces must be allowed to drain and the mounting tool must remain in position whilst this happens. Normally it takes some 24 hours before the sleeve can
support its full load. If stepped sleeves are to be mounted against bearings that are already greased, care should be taken to see that the injected oil does not mix with the grease and impair its lubricating properties. To dismount the sleeve it is only necessary to inject oil between the sleeve and shaft. When an oil film has been built up and separates the mating surfaces, an axial force will result from the stepped diameters, and the sleeve will slide from its seating without any external force being required. As the sleeve may be ejected from its seating quite suddenly, it is recommended that a stop be provided on the shaft. Further information on stepped sleeves dismounting and mounting are shown in the Chapter Principles of bearing selection and application, section dismounting, mounting and inspection page 84.
Dimension tables
6
278
279
Recommended dimensions for stepped sleeve and their seatings
Recommended dimensions for stepped sleeve with O-ring and their seating B2
B2 B1
3)
L4 L2
B3
B1
M4x0,5 4 0,5
0,5
2
2)
L3
4
4
L1
2
5
2 d5 d4
4
M4x0,5
0,5 d1 d2
M4x0,5
8
d3
D d4
d1
d3
d2
d4 d3
Shaft
Stepped sleeve
Dimensions Shaft
Stepped sleeve or ring
d1 h4
d3 H4
d4 H4
Stepped ring
Temperature differential1) d5 +0,5
D
d5
L2
L1 L1
d2 h4
D
4
B1
B2
B3
L1 j13
L2 j13
mm
L3 Stepped sleeve
Shaft
Dimensions Shaft
Stepped sleeve
d1 h4
L1 j13
degrees
mm
d2 f7
L4
L2
d3 H4
d4 +0,5
d5 H9
D
B1
B2
L2 j13
L3
Appropriate O-ring
Temperature differential1)
–
degrees
L4 +0,2
17 20
16,968 19,964
16,95 19,94
16,977 19,971
19 22
27 30
26 28
31 33
13 14
15 16
8,5 9
120 120
17 20
16,95 19,95
17 19
16,977 19,971
19 22
20,6 23,6
27 30
26 28
31 33
16 18
6,5 6,5
3,1 3,1
16,3×2,4 19,3×2,4
120 120
25 30
24,956 29,946
24,92 29,91
24,954 29,954
27 32
35 40
30 32
35 38
15 16
17 18
9,5 10
120 120
25 30
24,9 29,9
21 24
24,954 29,954
27 32
29,5 34,5
35 40
30 32
35 38
20 22
7 7
3,9 3,9
24,2×3,0 29,2×3,0
120 120
35 40
34,937 39,937
34,9 39,9
34,943 39,943
37 42
47 52
34 36
40 42
17 18
19 20
10,5 11
110 110
35 40
34,9 39,9
26 28
34,943 39,943
37 42
39,5 44,5
47 52
34 36
40 42
24 26
7 7
3,9 3,9
34,2×3,0 39,2×3,0
110 110
45 50
44,927 49,917
44,88 49,86
44,933 49,923
47 52
58 63
38 40
46 48
19 20
21 22
11,5 12
110 110
45 50
44,9 49,9
32 34
44,933 49,923
47 52
49,5 54,5
58 63
38 40
46 48
28 30
7 7
3,9 3,9
44,2×3,0 49,2×3,0
110 110
55 60
54,908 59,908
54,85 59,85
54,922 59,922
57 62
70 75
42 44
50 54
21 22
23 24
12,5 13
110 110
55 60
54,9 59,9
36 40
54,922 59,922
57 62
59,5 64,5
70 75
42 44
50 54
32 34
7 7
3,9 3,9
54,2×3,0 60,0×3,0
110 110
65 70
64,898 69,898
64,83 69,83
64,912 69,912
67 72
80 86
46 48
56 58
23 24
25 26
13,5 14
90 90
65 70
64,85 69,85
42 42
64,912 69,912
67 72
69,5 74,5
80 86
46 48
56 58
36 36
7 8
3,9 3,9
65,0×3,0 69,5×3,0
90 90
75 80
74,898 79,888
74,83 79,82
74,912 79,912
77 82
91 97
50 52
60 62
25 26
27 28
14,5 15
90 90
75 80
74,85 79,85
44 46
74,912 79,912
77 82
79,5 84,5
91 97
50 52
60 62
38 40
8 8
3,9 3,9
74,5×3,0 79,5×3,0
90 90
85 90
84,88 89,88
84,81 89,8
84,9 89,9
87 92
102 110
54 56
64 68
27 28
29 30
15,5 16
90 90
85 90
84,85 89,85
48 52
84,9 89,9
87 92
89,5 94,5
102 110
54 56
64 68
42 44
8 8
3,9 3,9
85,0×3,0 90,0×3,0
90 90
95 100
94,87 99,87
94,79 99,79
94,9 99,9
97 102
114 120
58 60
70 72
29 30
31 32
16,5 17
70 70
95 100
94,85 99,85
54 54
94,9 99,9
97 102
99,5 114 104,5 120
58 60
70 72
46 46
8 9
3,9 3,9
94,5×3,0 100,0×3,0
70 70
105 110
104,87 109,86
104,78 109,77
104,89 109,89
107 112
125 132
62 64
74 76
31 32
33 34
17,5 18
70 70
105 110
104,85 56 109,85 58
104,89 109,89
107 112
109,5 125 114,5 132
62 64
74 76
48 50
9 9
3,9 3,9
105,0×3,0 110,0×3,0
70 70
120 130
119,86 129,852
119,77 129,75
119,89 129,868
122 132
142 156
68 72
80 84
34 36
36 38
19 20
70 70
120 130
119,85 62 129,8 66
119,89 129,868
122 132
124,5 142 134,4 156
68 72
80 84
54 58
9 9
3,9 3,9
120,0×3,0 130,0×3,0
70 70
140 150
139,852 149,842
139,74 149,73
139,858 149,858
142 152
166 180
76 80
88 95
38 40
40 42
21 22
70 70
140 150
139,8 149,8
139,858 149,858
142 152
144,4 166 159 180
76 80
88 95
62 62
9 13
3,9 7,4
140,0×3,0 149,2×5,7
70 70
280
70 73
6
281
Recommended dimensions for stepped sleeve and their seatings
Recommended dimensions for stepped sleeve with O-ring and their seating B2
B2 B1
3)
L4 L2
B3
B1
M4x0,5 4 0,5
0,5
2
2)
L3
4
4
L1
2
5
2 d5 d4
4
M4x0,5
0,5 d1 d2
M4x0,5
8
d3
D d4
d1
d3
d2
d4 d3
Shaft
Stepped sleeve
Dimensions Shaft
Stepped sleeve or ring
d1 h4
d3 H4
d4 H4
Stepped ring
Temperature differential1) d5 +0,5
D
d5
L2
L1 L1
d2 h4
D
4
B1
B2
B3
L1 j13
L2 j13
mm
L3 Stepped sleeve
Shaft
Dimensions Shaft
Stepped sleeve
d1 h4
L1 j13
degrees
mm
d2 f7
L4
L2
d3 H4
d4 +0,5
d5 H9
D
B1
B2
L2 j13
L3
Appropriate O-ring
Temperature differential1)
–
degrees
L4 +0,2
160 170
159,842 169,842
159,73 169,72
159,858 169,848
162 172
190 205
84 88
99 103
42 44
44 46
23 24
70 70
160 170
159,8 169,8
77 81
159,858 169,848
162 172
169 179
190 205
84 88
99 103
66 70
13 13
7,4 7,4
159,2×5,7 169,2×5,7
70 70
180 190
179,832 189,834
179,71 189,7
179,848 189,836
182 192
220 230
92 96
110 114
46 48
48 50
25 26
70 70
180 190
179,8 189,8
88 92
179,848 189,836
182 192
189 199
220 230
92 96
110 114
74 78
13 13
7,4 7,4
179,2×5,7 189,2×5,7
70 70
200
199,834
199,7
199,836
202
245
100
118
50
52
27
60
200
199,8
96
199,836
202
209
245
100
118
82
13
7,4
199,2×5,7
60
1)
The difference in temperature between shaft and sleeve (ring) when mounting L3 = length of stepped sleeve over diameter d1 = L1 + B2 − B1 − 4 (mm) 3) L = length of stepped ring over diameter d = L − 4 + recessed d section (mm) 4 1 2 4 2)
282
1)
6
The difference in temperature between shaft and sleeve (ring) when mounting
283
Gauges Contents
Gauges Ring gauges, series GRA 30 Internal clearance gauges, series GB 30 Internal clearance gauges, series GB 49
286 286 290 293
7
285
7 Gauges
Gauges Conventional measuring methods and instruments are not always suitable for checking the seatings for rolling bearings, or measuring clearance or preload. SKF has therefore developed a range of gauges specially designed to meet the needs of rolling bearing applications. Ring gauges of series GRA 30 and taper gauges of series DMB can be used to check the most commonly occurring tapered seatings. Measurements can be made quickly and accurately. Whilst a ring gauge can only be used to check tapered seatings for one particular bearing size, the taper gauges of series DMB can be used for a given range of diameters, as well as for tapers other than 1:12. In order to be able to adjust the radial internal clearance or preload of cylindrical roller bearings with tapered bore when mounting, it is necessary to be able to accurately measure the circumscribed, or inscribed circle diameter of the rollers (diameter over or under the rollers). SKF gauges of series GB 30 and GB 49 enable these measurements to be made. They are simple to use and have high measuring accuracy. Detailed information on taper gauges of series DMB and other SKF measuring equipment will be supplied on request.
Ring gauges, series GRA 30 SKF ring gauges of series GRA 30 are practical aids for checking the tapered shaft seatings for bearings of series NN 30 K that are commonly used in machine tool applications. The gauges can also be used to check the shaft seatings for bearings of series N 10 K, but more particularly those of series NNU 49 BK; the width of the latter series differs only slightly from that of series NN 30 K. The ring gauges are available for tapered seatings up to 200 mm diameter, see product table, pages 288 – 289. For seatings with diameters larger than 200 mm, the requisite rings would be difficult to handle because of their weight, and the use of a taper gauge is recommended.
the seating, when the bearing is being mounted. The final value of the dimension Bb is determined during mounting, taking into account the desired bearing internal clearance. Ring gauges can also be used to check whether the reference surface of the shaft shoulder is at right angles to the centreline of the tapered seating, as well as to check the position and diameter of the seating. This is achieved by measuring the distance between the gauging surface of the ring gauge and the reference surface of the shaft using end measures. Errors of form, of the taper are checked using marking blue (➔ fig 1 ).
Measuring The gauging or reference face of ring gauges series GRA 30 is at the large end of the bore and is used to determine the position of the tapered seating relative to a reference surface on the shaft. This reference surface may be either in front of, or behind the gauging face of the ring gauge. Suitable dimensions for the tapered seating can be obtained from the product table. Where there is a free choice of dimensions it should be remembered that the reference length Bc should always be longer than the dimension Bb, the width of the intermediate ring, by an amount corresponding to the difference Bc – Bb, as the bearing will be driven up further than the ring gauge, on to
Measuring tapered seats with a GRA 30 series gauge Fig
1
7 Bc
db
da d
d1
Bb Bd
286
B
287
Ring gauges, GRA 30 series
Bc
da
db d
d1
B
Bb Bd
Bearing Designation
Bearing seating Dimensions da db Bb
Bc Nominal
Bd
Ring gauge Dimensions d d1
Mass
Designation
Bearing Designation
B
Bearing seating Dimensions da db Bb
Tolerance
–
mm
NN 3005 K
25,1
27
4
4,2
±0,1
19
25
46
NN 3006 K
30,1
32
6
6,2
±0,1
24
30
NN 3007 K
35,1
37
6
6,2
±0,1
25
NN 3008 K
40,1
42
8
8,2
±0,1
28
NN 3009 K
45,1
47
8
8,2
±0,1
NN 3010 K
50,1
52
8
8,2
NN 3011 K
55,15
57
8
8,3
NN 3012 K
60,15
62
10
NN 3013 K
65,15
67
NN 3014 K
70,15
NN 3015 K
75,15
NN 3016 K
Bd
Mass
Designation
kg
–
B
Tolerance
kg
–
–
mm
16
0,13
GRA 3005
NN 3024 K
120,25 124
15
15,5
±0,15
58,5
120
162
46
3,05
GRA 3024
52
19
0,18
GRA 3006
NN 3026 K
130,25 135
15
15,5
±0,15
64,5
130
175
52
3,95
GRA 3026
35
57
20
0,21
GRA 3007
NN 3028 K
140,3
145
15
15,6
±0,15
65
140
188
53
4,75
GRA 3028
40
62
21
0,26
GRA 3008
NN 3030 K
150,3
155
15
15,6
±0,15
68
150
200
56
5,6
GRA 3030
30
45
67
23
0,31
GRA 3009
NN 3032 K
160,3
165
15
15,6
±0,15
72
160
215
60
6,8
GRA 3032
±0,1
30
50
72
23
0,34
GRA 3010
NN 3034 K
170,3
176
15
15,6
±0,15
79
170
230
67
8,8
GRA 3034
±0,12
32,5
55
77
26
0,42
GRA 3011
NN 3036 K
180,35 187
20
20,7
±0,15
90,5
180
245
74
11,5
GRA 3036
10,3
±0,12
34,5
60
82
26
0,45
GRA 3012
NN 3038 K
190,35 197
20
20,7
±0,18
91,5
190
260
75
13
GRA 3038
10
10,3
±0,12
34,5
65
88
26
0,51
GRA 3013
NN 3040 K
200,35 207
20
20,7
±0,18
98,5
200
270
82
15
GRA 3040
73
10
10,3
±0,12
38,5
70
95
30
0,69
GRA 3014
78
10
10,3
±0,12
38,5
75
100
30
0,73
GRA 3015
80,15
83
12
12,3
±0,12
44,5
80
105
34
0,88
GRA 3016
NN 3017 K
85,2
88
12
12,4
±0,15
44
85
112
34
1
GRA 3017
NN 3018 K
90,2
93
12
12,4
±0,15
47
90
120
37
1,3
GRA 3018
NN 3019 K
95,2
98
12
12,4
±0,15
47
95
128
37
1,55
GRA 3019
NN 3020 K
100,2
103
12
12,4
±0,15
47
100
135
37
1,7
GRA 3020
NN 3021 K
105,2
109
12
12,4
±0,15
51
105
142
41
2,1
GRA 3021
NN 3022 K
110,25 114
12
12,5
±0,15
54,5
110
150
45
2,6
GRA 3022
288
mm
Bc Nominal
Ring gauge Dimensions d d1 mm
289
7
7 Gauges
Internal clearance gauges, series GB 30 SKF gauges of series GB 30 are available for use with double row cylindrical roller bearings NN 3006 K to NN 3040 K inclusive, and may also be used for the single row bearings of series N10 K. SKF gauges of series GB 30 are made in two different designs, depending on size. The illustration above the table on page 291 shows the design of gauges GB 3006 to GB 3020 inclusive. These can be used to measure the envelope diameter of the roller set (i.e. the diameter over the rollers when in contact with the inner ring raceway) to an accuracy of 1 µm. The larger gauges, sizes GB 3021 to GB 3040 inclusive, have the design that is shown in the right-hand illustration above the table on page 292, and a measuring accuracy of 2 µm. The body of gauges up to, and including size GB 3020 is in two parts; that of the larger sizes is slotted. The gauge body has two diametrically opposed gauging zones that are ground on its bore diameter. The body can be expanded by means of an adjustment screw. This enables the gauge to be pushed over the inner ring with roller and cage assembly without damaging the rollers and gauging surfaces. The measuring ring that is screwed to one half of the gauging ring, transmits the diameter measured by both halves of the gauging ring to the indicator dial.
290
Gauges, GB 30 series GB 3006 – GB 3020 Measuring Using a bore gauge, the raceway diameter of the mounted outer ring is measured, and the recorded dimension transferred to the centres of the gauging zones, taking into account the desired radial internal clearance or preload. The indicator of the GB 30 gauge is then set to zero. The inner ring with roller and cage assembly is pushed on to its tapered journal, and driven up until the indicator on the pre-set gauge again shows zero, when the gauge is placed in position around the roller set. Mounting instructions Detailed instruction for mounting cylindrical roller bearings with a separable outer ring, and the adjustment of clearance or preload using a gauge of series GB 30 will be found in the Chapter Principles of bearing selection and application, section mounting and dismounting, pages 93 – 96.
H
L
Bearing Designation
A
Gauge Dimensions L
H
Mass
Designation
kg
–
A
–
mm
NN 3006 K
107
175
36
2
GB 3006
NN 3007 K
112
180
37
2
GB 3007
NN 3008 K
117
185
39
2
GB 3008
NN 3009 K
129
197
40
2,5
GB 3009
NN 3010 K
134
202
40
2,5
GB 3010
NN 3011 K
144
212
43
3,5
GB 3011
NN 3012 K
152
222
44
4
GB 3012
NN 3013 K
157
225
44
4
GB 3013
NN 3014 K
164
232
48
5
GB 3014
NN 3015 K
168
236
48
5
GB 3015
NN 3016 K
176
244
52
6
GB 3016
NN 3017 K
185
253
53
6,5
GB 3017
NN 3018 K
198
266
56
8
GB 3018
NN 3019 K
203
271
56
9
GB 3019
NN 3020 K
212
280
56
9
GB 3020
7
291
Gauges, GB 30 series GB 3021 – GB 3040
Internal clearance gauges, series GB 49 SKF gauges of series GB 49 are available for use with double row cylindrical roller bearings NNU 4920 BK to NNU 4960 BK inclusive. There are two different designs of the gauge, depending on size. The illustration on the left-hand above the product table page 295 shows the design of gauges GB 4920 to GB 4938 inclusive, and are used to measure the internal diameter of the roller set, when the rollers are in contact with the outer ring raceway, to an accuracy of 1 µm. The illustration on the right-hand above the
H
L
Bearing Designation
A
Gauge Dimensions L
H
Mass
Designation
kg
–
A
–
mm
NN 3021 K
322
350
46
10,5
GB 3021
NN 3022 K
332
362
46
11
GB 3022
NN 3024 K
342
376
48
12
GB 3024
NN 3026 K
364
396
54
13
GB 3026
NN 3028 K
378
410
54
14,5
GB 3028
NN 3030 K
391
426
58
15
GB 3030
NN 3032 K
414
446
60
16
GB 3032
NN 3034 K
430
464
62
17
GB 3034
NN 3036 K
454
490
70
17,5
GB 3036
NN 3038 K
468
504
70
18
GB 3038
NN 3040 K
488
520
74
19
GB 3040
7
Internal clearance gauges GB 49 Fig
GB 4920 to GB 4938
292
product table page 295 shows the design of larger gauges, GB 4940 to GB 4960, and have a measuring accuracy of 2 µm. The body of gauges of series GB 49 is slotted, so that both gauging ring halves can be brought to bear on the roller set with the appropriate pressure, as a result of the inherent resilience of the material. The outside cylindrical surface of the gauging ring has two ground gauging zones at diametrically opposed positions. An adjustment screw permits the body of the gauge to be compressed, so that the gauge can be positioned inside the roller set without damaging the rollers or the gauging surfaces (➔ fig 2 ).
2
GB 4940 to GB 4960
293
7 Gauges Measuring After the gauge has been inserted in the roller and cage assembly, the adjustment screw is loosened until the two gauging surfaces are in contact with the roller set. The indicator of the gauge is then set to zero. The measured diameter inside the roller set is then taken by using a stirrup gauge and the indicator of the stirrup gauge set to zero. The inner ring is then driven up on its seating, on the spindle, until the indicator of the stirrup gauge, with which, the inner ring raceway is measured, shows the deviation from zero corresponding to the desired radial internal clearance or preload.
Gauges, GB 49 series
H H
GB 4920 to GB 4938
Bearing Designation
GB 4940 to GB 4960
Gauge Dimensions A
294
A
A
Mass
Designation
kg
–
H
–
mm
NNU 4920 BK
128
138
2,5
GB 4920
NNU 4921 BK
128
143
3
GB 4921
NNU 4922 BK
128
148
3
GB 4922
NNU 4924 BK
133
162
3,5
GB 4924
NNU 4926 BK
138
176
4
GB 4926
NNU 4928 BK
138
186
4,5
GB 4928
NNU 4930 BK
148
204
6
GB 4930
NNU 4932 BK
148
212
6,5
GB 4932
NNU 4934 BK
148
224
8
GB 4934
NNU 4936 BK
157
237
9,5
GB 4936
NNU 4938 BK
157
248
10,5
GB 4938
NNU 4940 BK
105
263
12
GB 4940
NNU 4944 BK
105
283
13
GB 4944
NNU 4948 BK
105
303
14
GB 4948
NNU 4952 BK
120
340
15
GB 4952
NNU 4956 BK
120
360
17
GB 4956
7
295
Other products and services Contents
Other products and services Machine tool precision bearing service centres Precision spindles Spindle service SKF Bearings for general engineering applications Linear motion products Bearing greases, Mounting Tools and condition monitoring equipment
298 298 298 299 299 300 300
8
297
8 Other products and services
Other products and services Machine tool precision bearing service centres SKF can help you in reducing downtime with three service centres located at Villar Perosa, Italy; Bethlehem, Pennsylvania (USA); Chino, Japan, to meet your precision machine tool bearings needs. These service centres provide custom preloaded and matched sets of high precision bearings, with very short turn-around. This translates into quicker deliveries, shorter lead times and reduced inventories. Publication 4808 “SKF precision bearing service centres”.
Precision spindles With design and production in Italy, Gamfior; Germany, SKF Spindles; USA, Russel T. Gilman; and Japan, PSC Chino, SKF is a worldwide supplier of a complete range of spindles from externally driven to high speed motorised units. SKF spindles are mainly used in the metal cutting machine tool and woodworking industries, but applications are also found in printing, medical and factory automation.
Spindle service SKF is operating a worldwide network of Spindle Service Centres, where professional reconditioning of almost any machine tools spindle are handled. Service centres are presently located in Austria, France, Germany, India, Italy, Japan, Sweden, UK and the US. Services offered include from complete reconditioning, bearing replacement, shaft and nose restoration to performance upgrade and root cause analysis.
SKF Bearings for general engineering applications Deep groove ball bearings, angular contact ball bearings, cylindrical roller bearings, taper roller bearings, etc. SKF General Catalogue; also SKF Interactive Engineering Catalogue available on CD-ROM or on-line under www.skf.com
Publication 5352 “SKF spindle service”.
Publications 4990 “Grinding solutions”; 5346 “Compact spindle for milling”; 5348 “Woodworking spindle”
8
298
299
8 Other products and services
Linear motion products SKF offers a wide range of rolled and ground ball screws for precision linear positioning systems and linear guides. Publication 4664/4 “Product range”, or on-line under www.linearmotion.skf.com
Bearing greases, mounting tools and condition monitoring equipment Rolling bearings are precision products, with dimensions in the order of microns (1/1 000 of a millimetre) are of importance. Furthermore, they are reliable machine parts having a long service life, provided that mounting and maintenance are carried out properly. In order to ensure expert mounting and maintenance, SKF has developed a wide range of mounting and dismounting tools, measuring instruments, lubricating greases and auxiliary products. In special seminars, the users are made familiar with the necessary expert knowledge and receive training. The range includes: mechanical tools, heaters, hydraulic equipment, instruments, bearing lubricants and lubricators. Condition monitoring solutions for measuring: temperature, speed and noise, oil cleanliness, vibration and bearing condition are also available. Publication MP3000 “SKF maintenance and lubrication products”.
300
Product index The product range shown in this catalogue comprises of more than 900 bearings, lock nuts and gauges. In order to enable the user to quickly find the technical data for a product known only by its designation, the products are listed by designation in alphanumerical order in this index. The page on which the product will be found is provided, as well as a code to identify the product type. The codes are explained as follows: AT1 AT2
Single direction angular contact thrust ball bearing Double direction angular contact thrust ball bearing
FBS GBA HAC HC1
Flanged cartridge unit Gauges Hybrid angular contact ball bearing Hybrid single row cylindrical roller bearings HT2 Hybrid double direction angular contact thrust ball bearing KMT Lock nut SAC All-steel angular contact ball bearing SC1 All-steel single row cylindrical roller bearings SC2 Full all-steel double row cylindrical roller bearings
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301
9 Products index
Designation
Code
Page
Designation
Code
Page
234407 B. . . . . . . . . . . . . . . . . . . . . . . 234408 B. . . . . . . . . . . . . . . . . . . . . . . 234409 B. . . . . . . . . . . . . . . . . . . . . . . 234410 B. . . . . . . . . . . . . . . . . . . . . . . 234411 B. . . . . . . . . . . . . . . . . . . . . . . 234412 . . . . . . . . . . . . . . . . . . . . . . . . 234413 . . . . . . . . . . . . . . . . . . . . . . . . 234414 . . . . . . . . . . . . . . . . . . . . . . . . 234415 B. . . . . . . . . . . . . . . . . . . . . . . 234416 . . . . . . . . . . . . . . . . . . . . . . . . 234417 . . . . . . . . . . . . . . . . . . . . . . . . 234418 . . . . . . . . . . . . . . . . . . . . . . . . 234419 B. . . . . . . . . . . . . . . . . . . . . . . 234420 . . . . . . . . . . . . . . . . . . . . . . . . 234422 B. . . . . . . . . . . . . . . . . . . . . . . 234424 . . . . . . . . . . . . . . . . . . . . . . . . 234426 . . . . . . . . . . . . . . . . . . . . . . . . 234428 B. . . . . . . . . . . . . . . . . . . . . . . 234430 B. . . . . . . . . . . . . . . . . . . . . . . 234432 B. . . . . . . . . . . . . . . . . . . . . . . 234434 B. . . . . . . . . . . . . . . . . . . . . . . 234436 B. . . . . . . . . . . . . . . . . . . . . . . 234438 B. . . . . . . . . . . . . . . . . . . . . . . 234440 B. . . . . . . . . . . . . . . . . . . . . . . 7000 ACX . . . . . . . . . . . . . . . . . . . . . . 7000 ACX/HC . . . . . . . . . . . . . . . . . . . 7000 CX . . . . . . . . . . . . . . . . . . . . . . . 7000 CX/HC . . . . . . . . . . . . . . . . . . . . 7001 ACX . . . . . . . . . . . . . . . . . . . . . . 7001 ACX/HC . . . . . . . . . . . . . . . . . . . 7001 CX . . . . . . . . . . . . . . . . . . . . . . . 7001 CX/HC . . . . . . . . . . . . . . . . . . . . 7002 ACX . . . . . . . . . . . . . . . . . . . . . . 7002 ACX/HC . . . . . . . . . . . . . . . . . . . 7002 CX . . . . . . . . . . . . . . . . . . . . . . . 7002 CX/HC . . . . . . . . . . . . . . . . . . . . 7003 ACX . . . . . . . . . . . . . . . . . . . . . . 7003 ACX/HC . . . . . . . . . . . . . . . . . . . 7003 CX . . . . . . . . . . . . . . . . . . . . . . . 7003 CX/HC . . . . . . . . . . . . . . . . . . . . 7004 ACE . . . . . . . . . . . . . . . . . . . . . . 7004 ACE/HC . . . . . . . . . . . . . . . . . . . 7004 ACX . . . . . . . . . . . . . . . . . . . . . . 7004 ACX/HC . . . . . . . . . . . . . . . . . . . 7004 CE . . . . . . . . . . . . . . . . . . . . . . . 7004 CE/HC . . . . . . . . . . . . . . . . . . . . 7004 CX . . . . . . . . . . . . . . . . . . . . . . . 7004 CX/HC . . . . . . . . . . . . . . . . . . . . 7005 ACE . . . . . . . . . . . . . . . . . . . . . .
AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
226 226 226 226 226 226 226 226 226 226 226 226 228 228 228 228 228 228 228 228 228 228 228 228 142 162 142 162 142 162 142 162 142 162 142 162 142 162 142 162 156 172 144 164 156 172 144 164 156
7005 ACE/HC . . . . . . . . . . . . . . . . . . . 7005 ACX . . . . . . . . . . . . . . . . . . . . . . 7005 ACX/HC . . . . . . . . . . . . . . . . . . . 7005 CE . . . . . . . . . . . . . . . . . . . . . . . 7005 CE/HC . . . . . . . . . . . . . . . . . . . . 7005 CX . . . . . . . . . . . . . . . . . . . . . . . 7005 CX/HC . . . . . . . . . . . . . . . . . . . . 7006 ACE . . . . . . . . . . . . . . . . . . . . . . 7006 ACE/HC . . . . . . . . . . . . . . . . . . . 7006 ACX . . . . . . . . . . . . . . . . . . . . . . 7006 ACX/HC . . . . . . . . . . . . . . . . . . . 7006 CE . . . . . . . . . . . . . . . . . . . . . . . 7006 CE/HC . . . . . . . . . . . . . . . . . . . . 7006 CX . . . . . . . . . . . . . . . . . . . . . . . 7006 CX/HC . . . . . . . . . . . . . . . . . . . . 7007 ACD . . . . . . . . . . . . . . . . . . . . . . 7007 ACD/HC . . . . . . . . . . . . . . . . . . . 7007 ACE . . . . . . . . . . . . . . . . . . . . . . 7007 ACE/HC . . . . . . . . . . . . . . . . . . . 7007 CD . . . . . . . . . . . . . . . . . . . . . . . 7007 CD/HC . . . . . . . . . . . . . . . . . . . . 7007 CE . . . . . . . . . . . . . . . . . . . . . . . 7007 CE/HC . . . . . . . . . . . . . . . . . . . . 7008 ACD . . . . . . . . . . . . . . . . . . . . . . 7008 ACD/HC . . . . . . . . . . . . . . . . . . . 7008 ACE . . . . . . . . . . . . . . . . . . . . . . 7008 ACE/HC . . . . . . . . . . . . . . . . . . . 7008 CD . . . . . . . . . . . . . . . . . . . . . . . 7008 CD/HC . . . . . . . . . . . . . . . . . . . . 7008 CE . . . . . . . . . . . . . . . . . . . . . . . 7008 CE/HC . . . . . . . . . . . . . . . . . . . . 7009 ACD . . . . . . . . . . . . . . . . . . . . . . 7009 ACD/HC . . . . . . . . . . . . . . . . . . . 7009 ACE . . . . . . . . . . . . . . . . . . . . . . 7009 ACE/HC . . . . . . . . . . . . . . . . . . . 7009 CD . . . . . . . . . . . . . . . . . . . . . . . 7009 CD/HC . . . . . . . . . . . . . . . . . . . . 7009 CE . . . . . . . . . . . . . . . . . . . . . . . 7009 CE/HC . . . . . . . . . . . . . . . . . . . . 7010 ACD . . . . . . . . . . . . . . . . . . . . . . 7010 ACD/HC . . . . . . . . . . . . . . . . . . . 7010 ACE . . . . . . . . . . . . . . . . . . . . . . 7010 ACE/HC . . . . . . . . . . . . . . . . . . . 7010 CD . . . . . . . . . . . . . . . . . . . . . . . 7010 CD/HC . . . . . . . . . . . . . . . . . . . . 7010 CE . . . . . . . . . . . . . . . . . . . . . . . 7010 CE/HC . . . . . . . . . . . . . . . . . . . . 7011 ACD . . . . . . . . . . . . . . . . . . . . . . 7011 ACD/HC . . . . . . . . . . . . . . . . . . .
HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC
172 144 164 156 172 144 164 156 172 144 164 156 172 144 164 144 164 156 172 144 164 156 172 144 164 156 172 144 164 156 172 146 166 156 172 146 166 156 172 146 166 156 172 146 166 156 172 146 166
302
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
303
9
9
Products index
Designation
Code
Page
Designation
Code
Page
7011 ACE . . . . . . . . . . . . . . . . . . . . . . 7011 ACE/HC . . . . . . . . . . . . . . . . . . . 7011 CD . . . . . . . . . . . . . . . . . . . . . . . 7011 CD/HC . . . . . . . . . . . . . . . . . . . . 7011 CE . . . . . . . . . . . . . . . . . . . . . . . 7011 CE/HC . . . . . . . . . . . . . . . . . . . . 7012 ACD . . . . . . . . . . . . . . . . . . . . . . 7012 ACD/HC . . . . . . . . . . . . . . . . . . . 7012 ACE . . . . . . . . . . . . . . . . . . . . . . 7012 ACE/HC . . . . . . . . . . . . . . . . . . . 7012 CD . . . . . . . . . . . . . . . . . . . . . . . 7012 CD/HC . . . . . . . . . . . . . . . . . . . . 7012 CE . . . . . . . . . . . . . . . . . . . . . . . 7012 CE/HC . . . . . . . . . . . . . . . . . . . . 7013 ACD . . . . . . . . . . . . . . . . . . . . . . 7013 ACD/HC . . . . . . . . . . . . . . . . . . . 7013 ACE . . . . . . . . . . . . . . . . . . . . . . 7013 ACE/HC . . . . . . . . . . . . . . . . . . . 7013 CD . . . . . . . . . . . . . . . . . . . . . . . 7013 CD/HC . . . . . . . . . . . . . . . . . . . . 7013 CE . . . . . . . . . . . . . . . . . . . . . . . 7013 CE/HC . . . . . . . . . . . . . . . . . . . . 7014 ACD . . . . . . . . . . . . . . . . . . . . . . 7014 ACD/HC . . . . . . . . . . . . . . . . . . . 7014 ACE . . . . . . . . . . . . . . . . . . . . . . 7014 ACE/HC . . . . . . . . . . . . . . . . . . . 7014 CD . . . . . . . . . . . . . . . . . . . . . . . 7014 CD/HC . . . . . . . . . . . . . . . . . . . . 7014 CE . . . . . . . . . . . . . . . . . . . . . . . 7014 CE/HC . . . . . . . . . . . . . . . . . . . . 7015 ACD . . . . . . . . . . . . . . . . . . . . . . 7015 ACD/HC . . . . . . . . . . . . . . . . . . . 7015 ACE . . . . . . . . . . . . . . . . . . . . . . 7015 ACE/HC . . . . . . . . . . . . . . . . . . . 7015 CD . . . . . . . . . . . . . . . . . . . . . . . 7015 CD/HC . . . . . . . . . . . . . . . . . . . . 7015 CE . . . . . . . . . . . . . . . . . . . . . . . 7015 CE/HC . . . . . . . . . . . . . . . . . . . . 7016 ACD . . . . . . . . . . . . . . . . . . . . . . 7016 ACD/HC . . . . . . . . . . . . . . . . . . . 7016 ACE . . . . . . . . . . . . . . . . . . . . . . 7016 ACE/HC . . . . . . . . . . . . . . . . . . . 7016 CD . . . . . . . . . . . . . . . . . . . . . . . 7016 CD/HC . . . . . . . . . . . . . . . . . . . . 7016 CE . . . . . . . . . . . . . . . . . . . . . . . 7016 CE/HC . . . . . . . . . . . . . . . . . . . . 7017 ACD . . . . . . . . . . . . . . . . . . . . . . 7017 ACD/HC . . . . . . . . . . . . . . . . . . . 7017 ACE . . . . . . . . . . . . . . . . . . . . . .
SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC
158 174 146 166 158 174 146 166 158 174 146 166 158 174 146 166 158 174 146 166 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158
7017 ACE/HC . . . . . . . . . . . . . . . . . . . 7017 CD . . . . . . . . . . . . . . . . . . . . . . . 7017 CD/HC . . . . . . . . . . . . . . . . . . . . 7017 CE . . . . . . . . . . . . . . . . . . . . . . . 7017 CE/HC . . . . . . . . . . . . . . . . . . . . 7018 ACD . . . . . . . . . . . . . . . . . . . . . . 7018 ACD/HC . . . . . . . . . . . . . . . . . . . 7018 ACE . . . . . . . . . . . . . . . . . . . . . . 7018 ACE/HC . . . . . . . . . . . . . . . . . . . 7018 CD . . . . . . . . . . . . . . . . . . . . . . . 7018 CD/HC . . . . . . . . . . . . . . . . . . . . 7018 CE . . . . . . . . . . . . . . . . . . . . . . . 7018 CE/HC . . . . . . . . . . . . . . . . . . . . 7019 ACD . . . . . . . . . . . . . . . . . . . . . . 7019 ACD/HC . . . . . . . . . . . . . . . . . . . 7019 ACE . . . . . . . . . . . . . . . . . . . . . . 7019 ACE/HC . . . . . . . . . . . . . . . . . . . 7019 CD . . . . . . . . . . . . . . . . . . . . . . . 7019 CD/HC . . . . . . . . . . . . . . . . . . . . 7019 CE . . . . . . . . . . . . . . . . . . . . . . . 7019 CE/HC . . . . . . . . . . . . . . . . . . . . 7020 ACD . . . . . . . . . . . . . . . . . . . . . . 7020 ACD/HC . . . . . . . . . . . . . . . . . . . 7020 ACE . . . . . . . . . . . . . . . . . . . . . . 7020 ACE/HC . . . . . . . . . . . . . . . . . . . 7020 CD . . . . . . . . . . . . . . . . . . . . . . . 7020 CD/HC . . . . . . . . . . . . . . . . . . . . 7020 CE . . . . . . . . . . . . . . . . . . . . . . . 7020 CE/HC . . . . . . . . . . . . . . . . . . . . 7021 ACD . . . . . . . . . . . . . . . . . . . . . . 7021 CD . . . . . . . . . . . . . . . . . . . . . . . 7022 ACD . . . . . . . . . . . . . . . . . . . . . . 7022 CD . . . . . . . . . . . . . . . . . . . . . . . 7024 ACD . . . . . . . . . . . . . . . . . . . . . . 7024 CD . . . . . . . . . . . . . . . . . . . . . . . 7026 ACD . . . . . . . . . . . . . . . . . . . . . . 7026 CD . . . . . . . . . . . . . . . . . . . . . . . 7028 ACD . . . . . . . . . . . . . . . . . . . . . . 7028 CD . . . . . . . . . . . . . . . . . . . . . . . 7030 ACD . . . . . . . . . . . . . . . . . . . . . . 7030 CD . . . . . . . . . . . . . . . . . . . . . . . 7032 ACD . . . . . . . . . . . . . . . . . . . . . . 7032 CD . . . . . . . . . . . . . . . . . . . . . . . 7034 ACD . . . . . . . . . . . . . . . . . . . . . . 7034 CD . . . . . . . . . . . . . . . . . . . . . . . 7036 ACD . . . . . . . . . . . . . . . . . . . . . . 7036 CD . . . . . . . . . . . . . . . . . . . . . . . 7038 ACD . . . . . . . . . . . . . . . . . . . . . . 7038 CD . . . . . . . . . . . . . . . . . . . . . . .
HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC
174 148 168 158 174 148 168 160 176 148 168 160 176 150 168 160 176 150 168 160 176 150 168 160 176 150 168 160 176 150 150 150 150 150 150 152 152 152 152 152 152 152 152 152 152 152 152 152 152
304
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
305
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Products index
Designation
Code
Page
Designation
Code
Page
7040 ACD . . . . . . . . . . . . . . . . . . . . . . 7040 CD . . . . . . . . . . . . . . . . . . . . . . . 7044 ACD . . . . . . . . . . . . . . . . . . . . . . 7044 CD . . . . . . . . . . . . . . . . . . . . . . . 7048 ACD . . . . . . . . . . . . . . . . . . . . . . 7048 CD . . . . . . . . . . . . . . . . . . . . . . . 708 CX . . . . . . . . . . . . . . . . . . . . . . . . 708 CX/HC . . . . . . . . . . . . . . . . . . . . . 709 CX . . . . . . . . . . . . . . . . . . . . . . . . 709 CX/HC . . . . . . . . . . . . . . . . . . . . . 71900 ACX . . . . . . . . . . . . . . . . . . . . . 71900 ACX/HC . . . . . . . . . . . . . . . . . . 71900 CX . . . . . . . . . . . . . . . . . . . . . . 71900 CX/HC . . . . . . . . . . . . . . . . . . . 71901 ACX . . . . . . . . . . . . . . . . . . . . . 71901 ACX/HC . . . . . . . . . . . . . . . . . . 71901 CX . . . . . . . . . . . . . . . . . . . . . . 71901 CX/HC . . . . . . . . . . . . . . . . . . . 71902 ACX . . . . . . . . . . . . . . . . . . . . . 71902 ACX/HC . . . . . . . . . . . . . . . . . . 71902 CX . . . . . . . . . . . . . . . . . . . . . . 71902 CX/HC . . . . . . . . . . . . . . . . . . . 71903 ACX . . . . . . . . . . . . . . . . . . . . . 71903 ACX/HC . . . . . . . . . . . . . . . . . . 71903 CX . . . . . . . . . . . . . . . . . . . . . . 71903 CX/HC . . . . . . . . . . . . . . . . . . . 71904 ACE . . . . . . . . . . . . . . . . . . . . . 71904 ACE/HC . . . . . . . . . . . . . . . . . . 71904 ACX . . . . . . . . . . . . . . . . . . . . . 71904 ACX/HC . . . . . . . . . . . . . . . . . . 71904 CE . . . . . . . . . . . . . . . . . . . . . . 71904 CE/HC . . . . . . . . . . . . . . . . . . . 71904 CX . . . . . . . . . . . . . . . . . . . . . . 71904 CX/HC . . . . . . . . . . . . . . . . . . . 71905 ACE . . . . . . . . . . . . . . . . . . . . . 71905 ACE/HC . . . . . . . . . . . . . . . . . . 71905 ACX . . . . . . . . . . . . . . . . . . . . . 71905 ACX/HC . . . . . . . . . . . . . . . . . . 71905 CE . . . . . . . . . . . . . . . . . . . . . . 71905 CE/HC . . . . . . . . . . . . . . . . . . . 71905 CX . . . . . . . . . . . . . . . . . . . . . . 71905 CX/HC . . . . . . . . . . . . . . . . . . . 71906 ACE . . . . . . . . . . . . . . . . . . . . . 71906 ACE/HC . . . . . . . . . . . . . . . . . . 71906 ACX . . . . . . . . . . . . . . . . . . . . . 71906 ACX/HC . . . . . . . . . . . . . . . . . . 71906 CE . . . . . . . . . . . . . . . . . . . . . . 71906 CE/HC . . . . . . . . . . . . . . . . . . . 71906 CX . . . . . . . . . . . . . . . . . . . . . .
SAC SAC SAC SAC SAC SAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC
154 154 154 154 154 154 142 162 142 162 142 162 142 162 142 162 142 162 142 162 142 162 142 162 142 162 156 172 144 164 156 172 144 164 156 172 144 164 156 172 144 164 156 172 144 164 156 172 144
71906 CX/HC . . . . . . . . . . . . . . . . . . . 71907 ACD . . . . . . . . . . . . . . . . . . . . . 71907 ACD/HC . . . . . . . . . . . . . . . . . . 71907 ACE . . . . . . . . . . . . . . . . . . . . . 71907 ACE/HC . . . . . . . . . . . . . . . . . . 71907 CD . . . . . . . . . . . . . . . . . . . . . . 71907 CD/HC . . . . . . . . . . . . . . . . . . . 71907 CE . . . . . . . . . . . . . . . . . . . . . . 71907 CE/HC . . . . . . . . . . . . . . . . . . . 71908 ACD . . . . . . . . . . . . . . . . . . . . . 71908 ACD/HC . . . . . . . . . . . . . . . . . . 71908 ACE . . . . . . . . . . . . . . . . . . . . . 71908 ACE/HC . . . . . . . . . . . . . . . . . . 71908 CD . . . . . . . . . . . . . . . . . . . . . . 71908 CD/HC . . . . . . . . . . . . . . . . . . . 71908 CE . . . . . . . . . . . . . . . . . . . . . . 71908 CE/HC . . . . . . . . . . . . . . . . . . . 71909 ACD . . . . . . . . . . . . . . . . . . . . . 71909 ACD/HC . . . . . . . . . . . . . . . . . . 71909 ACE . . . . . . . . . . . . . . . . . . . . . 71909 ACE/HC . . . . . . . . . . . . . . . . . . 71909 CD . . . . . . . . . . . . . . . . . . . . . . 71909 CD/HC . . . . . . . . . . . . . . . . . . . 71909 CE . . . . . . . . . . . . . . . . . . . . . . 71909 CE/HC . . . . . . . . . . . . . . . . . . . 71910 ACD . . . . . . . . . . . . . . . . . . . . . 71910 ACD/HC . . . . . . . . . . . . . . . . . . 71910 ACE . . . . . . . . . . . . . . . . . . . . . 71910 ACE/HC . . . . . . . . . . . . . . . . . . 71910 CD . . . . . . . . . . . . . . . . . . . . . . 71910 CD/HC . . . . . . . . . . . . . . . . . . . 71910 CE . . . . . . . . . . . . . . . . . . . . . . 71910 CE/HC . . . . . . . . . . . . . . . . . . . 71911 ACD . . . . . . . . . . . . . . . . . . . . . 71911 ACD/HC . . . . . . . . . . . . . . . . . . 71911 ACE . . . . . . . . . . . . . . . . . . . . . 71911 ACE/HC . . . . . . . . . . . . . . . . . . 71911 CD . . . . . . . . . . . . . . . . . . . . . . 71911 CD/HC . . . . . . . . . . . . . . . . . . . 71911 CE . . . . . . . . . . . . . . . . . . . . . . 71911 CE/HC . . . . . . . . . . . . . . . . . . . 71912 ACD . . . . . . . . . . . . . . . . . . . . . 71912 ACD/HC . . . . . . . . . . . . . . . . . . 71912 ACE . . . . . . . . . . . . . . . . . . . . . 71912 ACE/HC . . . . . . . . . . . . . . . . . . 71912 CD . . . . . . . . . . . . . . . . . . . . . . 71912 CD/HC . . . . . . . . . . . . . . . . . . . 71912 CE . . . . . . . . . . . . . . . . . . . . . . 71912 CE/HC . . . . . . . . . . . . . . . . . . .
HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC
164 144 164 156 172 144 164 156 172 144 164 156 172 144 164 156 172 146 166 156 172 146 166 156 172 146 166 156 172 146 166 156 172 146 166 158 174 146 166 158 174 146 166 158 174 146 166 158 174
306
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307
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Products index
Designation
Code
Page
Designation
Code
Page
71913 ACD . . . . . . . . . . . . . . . . . . . . . 71913 ACD/HC . . . . . . . . . . . . . . . . . . 71913 ACE . . . . . . . . . . . . . . . . . . . . . 71913 ACE/HC . . . . . . . . . . . . . . . . . . 71913 CD . . . . . . . . . . . . . . . . . . . . . . 71913 CD/HC . . . . . . . . . . . . . . . . . . . 71913 CE . . . . . . . . . . . . . . . . . . . . . . 71913 CE/HC . . . . . . . . . . . . . . . . . . . 71914 ACD . . . . . . . . . . . . . . . . . . . . . 71914 ACD/HC . . . . . . . . . . . . . . . . . . 71914 ACE . . . . . . . . . . . . . . . . . . . . . 71914 ACE/HC . . . . . . . . . . . . . . . . . . 71914 CD . . . . . . . . . . . . . . . . . . . . . . 71914 CD/HC . . . . . . . . . . . . . . . . . . . 71914 CE . . . . . . . . . . . . . . . . . . . . . . 71914 CE/HC . . . . . . . . . . . . . . . . . . . 71915 ACD . . . . . . . . . . . . . . . . . . . . . 71915 ACD/HC . . . . . . . . . . . . . . . . . . 71915 ACE . . . . . . . . . . . . . . . . . . . . . 71915 ACE/HC . . . . . . . . . . . . . . . . . . 71915 CD . . . . . . . . . . . . . . . . . . . . . . 71915 CD/HC . . . . . . . . . . . . . . . . . . . 71915 CE . . . . . . . . . . . . . . . . . . . . . . 71915 CE/HC . . . . . . . . . . . . . . . . . . . 71916 ACD . . . . . . . . . . . . . . . . . . . . . 71916 ACD/HC . . . . . . . . . . . . . . . . . . 71916 ACE . . . . . . . . . . . . . . . . . . . . . 71916 ACE/HC . . . . . . . . . . . . . . . . . . 71916 CD . . . . . . . . . . . . . . . . . . . . . . 71916 CD/HC . . . . . . . . . . . . . . . . . . . 71916 CE . . . . . . . . . . . . . . . . . . . . . . 71916 CE/HC . . . . . . . . . . . . . . . . . . . 71917 ACD . . . . . . . . . . . . . . . . . . . . . 71917 ACD/HC . . . . . . . . . . . . . . . . . . 71917 ACE . . . . . . . . . . . . . . . . . . . . . 71917 ACE/HC . . . . . . . . . . . . . . . . . . 71917 CD . . . . . . . . . . . . . . . . . . . . . . 71917 CD/HC . . . . . . . . . . . . . . . . . . . 71917 CE . . . . . . . . . . . . . . . . . . . . . . 71917 CE/HC . . . . . . . . . . . . . . . . . . . 71918 ACD . . . . . . . . . . . . . . . . . . . . . 71918 ACD/HC . . . . . . . . . . . . . . . . . . 71918 ACE . . . . . . . . . . . . . . . . . . . . . 71918 ACE/HC . . . . . . . . . . . . . . . . . . 71918 CD . . . . . . . . . . . . . . . . . . . . . . 71918 CD/HC . . . . . . . . . . . . . . . . . . . 71918 CE . . . . . . . . . . . . . . . . . . . . . . 71918 CE/HC . . . . . . . . . . . . . . . . . . . 71919 ACD . . . . . . . . . . . . . . . . . . . . .
SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC
146 166 158 174 146 166 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 158 174 148 168 160 176 148 168 160 176 150
71919 ACD/HC . . . . . . . . . . . . . . . . . . 71919 ACE . . . . . . . . . . . . . . . . . . . . . 71919 ACE/HC . . . . . . . . . . . . . . . . . . 71919 CD . . . . . . . . . . . . . . . . . . . . . . 71919 CD/HC . . . . . . . . . . . . . . . . . . . 71919 CE . . . . . . . . . . . . . . . . . . . . . . 71919 CE/HC . . . . . . . . . . . . . . . . . . . 71920 ACD . . . . . . . . . . . . . . . . . . . . . 71920 ACD/HC . . . . . . . . . . . . . . . . . . 71920 ACE . . . . . . . . . . . . . . . . . . . . . 71920 ACE/HC . . . . . . . . . . . . . . . . . . 71920 CD . . . . . . . . . . . . . . . . . . . . . . 71920 CD/HC . . . . . . . . . . . . . . . . . . . 71920 CE . . . . . . . . . . . . . . . . . . . . . . 71920 CE/HC . . . . . . . . . . . . . . . . . . . 71921 ACD . . . . . . . . . . . . . . . . . . . . . 71921 ACD/HC . . . . . . . . . . . . . . . . . . 71921 ACE . . . . . . . . . . . . . . . . . . . . . 71921 ACE/HC . . . . . . . . . . . . . . . . . . 71921 CD . . . . . . . . . . . . . . . . . . . . . . 71921 CD/HC . . . . . . . . . . . . . . . . . . . 71921 CE . . . . . . . . . . . . . . . . . . . . . . 71921 CE/HC . . . . . . . . . . . . . . . . . . . 71922 ACD . . . . . . . . . . . . . . . . . . . . . 71922 ACD/HC . . . . . . . . . . . . . . . . . . 71922 ACE . . . . . . . . . . . . . . . . . . . . . 71922 ACE/HC . . . . . . . . . . . . . . . . . . 71922 CD . . . . . . . . . . . . . . . . . . . . . . 71922 CD/HC . . . . . . . . . . . . . . . . . . . 71922 CE . . . . . . . . . . . . . . . . . . . . . . 71922 CE/HC . . . . . . . . . . . . . . . . . . . 71924 ACD . . . . . . . . . . . . . . . . . . . . . 71924 ACD/HC . . . . . . . . . . . . . . . . . . 71924 ACE . . . . . . . . . . . . . . . . . . . . . 71924 ACE/HC . . . . . . . . . . . . . . . . . . 71924 CD . . . . . . . . . . . . . . . . . . . . . . 71924 CD/HC . . . . . . . . . . . . . . . . . . . 71924 CE . . . . . . . . . . . . . . . . . . . . . . 71924 CE/HC . . . . . . . . . . . . . . . . . . . 71926 ACD . . . . . . . . . . . . . . . . . . . . . 71926 ACD/HC . . . . . . . . . . . . . . . . . . 71926 CD . . . . . . . . . . . . . . . . . . . . . . 71926 CD/HC . . . . . . . . . . . . . . . . . . . 71928 ACD . . . . . . . . . . . . . . . . . . . . . 71928 ACD/HC . . . . . . . . . . . . . . . . . . 71928 CD . . . . . . . . . . . . . . . . . . . . . . 71928 CD/HC . . . . . . . . . . . . . . . . . . . 71930 ACD . . . . . . . . . . . . . . . . . . . . . 71930 CD . . . . . . . . . . . . . . . . . . . . . .
HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC SAC
168 160 176 150 168 160 176 150 168 160 176 150 168 160 176 150 170 160 176 150 170 160 176 150 170 160 176 150 170 160 176 150 170 160 176 150 170 160 176 152 170 152 170 152 170 152 170 152 152
308
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
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71932 ACD . . . . . . . . . . . . . . . . . . . . . 71932 CD . . . . . . . . . . . . . . . . . . . . . . 71934 ACD . . . . . . . . . . . . . . . . . . . . . 71934 CD . . . . . . . . . . . . . . . . . . . . . . 71936 ACD . . . . . . . . . . . . . . . . . . . . . 71936 CD . . . . . . . . . . . . . . . . . . . . . . 71938 ACD . . . . . . . . . . . . . . . . . . . . . 71938 CD . . . . . . . . . . . . . . . . . . . . . . 71940 ACD . . . . . . . . . . . . . . . . . . . . . 71940 CD . . . . . . . . . . . . . . . . . . . . . . 71944 ACD . . . . . . . . . . . . . . . . . . . . . 71944 CD . . . . . . . . . . . . . . . . . . . . . . 7200 ACX . . . . . . . . . . . . . . . . . . . . . . 7200 ACX/HC . . . . . . . . . . . . . . . . . . . 7200 CX . . . . . . . . . . . . . . . . . . . . . . . 7200 CX/HC . . . . . . . . . . . . . . . . . . . . 7201 ACX . . . . . . . . . . . . . . . . . . . . . . 7201 ACX/HC . . . . . . . . . . . . . . . . . . . 7201 CX . . . . . . . . . . . . . . . . . . . . . . . 7201 CX/HC . . . . . . . . . . . . . . . . . . . . 7202 ACX . . . . . . . . . . . . . . . . . . . . . . 7202 ACX/HC . . . . . . . . . . . . . . . . . . . 7202 CX . . . . . . . . . . . . . . . . . . . . . . . 7202 CX/HC . . . . . . . . . . . . . . . . . . . . 7203 ACX . . . . . . . . . . . . . . . . . . . . . . 7203 ACX/HC . . . . . . . . . . . . . . . . . . . 7203 CX . . . . . . . . . . . . . . . . . . . . . . . 7203 CX/HC . . . . . . . . . . . . . . . . . . . . 7204 ACX . . . . . . . . . . . . . . . . . . . . . . 7204 ACX/HC . . . . . . . . . . . . . . . . . . . 7204 CX . . . . . . . . . . . . . . . . . . . . . . . 7204 CX/HC . . . . . . . . . . . . . . . . . . . . 7205 ACX . . . . . . . . . . . . . . . . . . . . . . 7205 ACX/HC . . . . . . . . . . . . . . . . . . . 7205 CX . . . . . . . . . . . . . . . . . . . . . . . 7205 CX/HC . . . . . . . . . . . . . . . . . . . . 7206 ACD . . . . . . . . . . . . . . . . . . . . . . 7206 ACD/HC . . . . . . . . . . . . . . . . . . . 7206 CD . . . . . . . . . . . . . . . . . . . . . . . 7206 CD/HC . . . . . . . . . . . . . . . . . . . . 7207 ACD . . . . . . . . . . . . . . . . . . . . . . 7207 ACD/HC . . . . . . . . . . . . . . . . . . . 7207 CD . . . . . . . . . . . . . . . . . . . . . . . 7207 CD/HC . . . . . . . . . . . . . . . . . . . . 7208 ACD . . . . . . . . . . . . . . . . . . . . . . 7208 ACD/HC . . . . . . . . . . . . . . . . . . . 7208 CD . . . . . . . . . . . . . . . . . . . . . . . 7208 CD/HC . . . . . . . . . . . . . . . . . . . . 7209 ACD . . . . . . . . . . . . . . . . . . . . . .
SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC HAC SAC
152 152 152 152 152 152 152 152 154 154 154 154 142 162 142 162 142 162 142 162 142 162 142 162 142 162 142 162 144 164 144 164 144 164 144 164 144 164 144 164 144 164 144 164 144 164 144 164 146
7209 ACD/HC . . . . . . . . . . . . . . . . . . . 7209 CD . . . . . . . . . . . . . . . . . . . . . . . 7209 CD/HC . . . . . . . . . . . . . . . . . . . . 7210 ACD . . . . . . . . . . . . . . . . . . . . . . 7210 ACD/HC . . . . . . . . . . . . . . . . . . . 7210 CD . . . . . . . . . . . . . . . . . . . . . . . 7210 CD/HC . . . . . . . . . . . . . . . . . . . . 7211 ACD . . . . . . . . . . . . . . . . . . . . . . 7211 ACD/HC . . . . . . . . . . . . . . . . . . . 7211 CD . . . . . . . . . . . . . . . . . . . . . . . 7211 CD/HC . . . . . . . . . . . . . . . . . . . . 7212 ACD . . . . . . . . . . . . . . . . . . . . . . 7212 ACD/HC . . . . . . . . . . . . . . . . . . . 7212 CD . . . . . . . . . . . . . . . . . . . . . . . 7212 CD/HC . . . . . . . . . . . . . . . . . . . . 7213 ACD . . . . . . . . . . . . . . . . . . . . . . 7213 CD . . . . . . . . . . . . . . . . . . . . . . . 7214 ACD . . . . . . . . . . . . . . . . . . . . . . 7214 CD . . . . . . . . . . . . . . . . . . . . . . . 7215 ACD . . . . . . . . . . . . . . . . . . . . . . 7215 CD . . . . . . . . . . . . . . . . . . . . . . . 7216 ACD . . . . . . . . . . . . . . . . . . . . . . 7216 CD . . . . . . . . . . . . . . . . . . . . . . . 7217 ACD . . . . . . . . . . . . . . . . . . . . . . 7217 CD . . . . . . . . . . . . . . . . . . . . . . . 7218 ACD . . . . . . . . . . . . . . . . . . . . . . 7218 CD . . . . . . . . . . . . . . . . . . . . . . . 7219 ACD . . . . . . . . . . . . . . . . . . . . . . 7219 CD . . . . . . . . . . . . . . . . . . . . . . . 7220 ACD . . . . . . . . . . . . . . . . . . . . . . 7220 CD . . . . . . . . . . . . . . . . . . . . . . . 7221 ACD . . . . . . . . . . . . . . . . . . . . . . 7221 CD . . . . . . . . . . . . . . . . . . . . . . . 7222 ACD . . . . . . . . . . . . . . . . . . . . . . 7222 CD . . . . . . . . . . . . . . . . . . . . . . . 7224 ACD . . . . . . . . . . . . . . . . . . . . . . 7224 CD . . . . . . . . . . . . . . . . . . . . . . . BSA 201 C . . . . . . . . . . . . . . . . . . . . . BSA 202 C . . . . . . . . . . . . . . . . . . . . . BSA 203 C . . . . . . . . . . . . . . . . . . . . . BSA 204 C . . . . . . . . . . . . . . . . . . . . . BSA 205 C . . . . . . . . . . . . . . . . . . . . . BSA 206 C . . . . . . . . . . . . . . . . . . . . . BSA 207 C . . . . . . . . . . . . . . . . . . . . . BSA 212 C . . . . . . . . . . . . . . . . . . . . . BSA 215 C . . . . . . . . . . . . . . . . . . . . . BSA 305 C . . . . . . . . . . . . . . . . . . . . . BSA 306 C . . . . . . . . . . . . . . . . . . . . . BSA 308 C . . . . . . . . . . . . . . . . . . . . .
HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
166 146 166 146 166 146 166 146 166 146 166 146 166 146 166 146 146 148 148 148 148 148 148 148 148 148 148 150 150 150 150 150 150 150 150 150 150 252 252 252 252 252 252 252 252 252 252 252 252
310
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311
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BSD 2047 C . . . . . . . . . . . . . . . . . . . . BSD 2562 C . . . . . . . . . . . . . . . . . . . . BSD 3062 C . . . . . . . . . . . . . . . . . . . . BSD 3572 C . . . . . . . . . . . . . . . . . . . . BSD 4072 C . . . . . . . . . . . . . . . . . . . . BSD 4090 C . . . . . . . . . . . . . . . . . . . . BSD 45100 C . . . . . . . . . . . . . . . . . . . BSD 4575 C . . . . . . . . . . . . . . . . . . . . BSD 50100 C . . . . . . . . . . . . . . . . . . . BSD 55100 C . . . . . . . . . . . . . . . . . . . BSD 55120 C . . . . . . . . . . . . . . . . . . . BSD 60120 C . . . . . . . . . . . . . . . . . . . BTM 100 A . . . . . . . . . . . . . . . . . . . . . BTM 100 A/HC . . . . . . . . . . . . . . . . . . BTM 100 B . . . . . . . . . . . . . . . . . . . . . BTM 100 B/HC . . . . . . . . . . . . . . . . . . BTM 110 A . . . . . . . . . . . . . . . . . . . . . BTM 110 A/HC . . . . . . . . . . . . . . . . . . BTM 110 B . . . . . . . . . . . . . . . . . . . . . BTM 110 B/HC . . . . . . . . . . . . . . . . . . BTM 120 A . . . . . . . . . . . . . . . . . . . . . BTM 120 A/HC . . . . . . . . . . . . . . . . . . BTM 120 B . . . . . . . . . . . . . . . . . . . . . BTM 120 B/HC . . . . . . . . . . . . . . . . . . BTM 130 A . . . . . . . . . . . . . . . . . . . . . BTM 130 A/HC . . . . . . . . . . . . . . . . . . BTM 130 B . . . . . . . . . . . . . . . . . . . . . BTM 130 B/HC . . . . . . . . . . . . . . . . . . BTM 60 A . . . . . . . . . . . . . . . . . . . . . . BTM 60 A/HC . . . . . . . . . . . . . . . . . . . BTM 60 B . . . . . . . . . . . . . . . . . . . . . . BTM 60 B/HC . . . . . . . . . . . . . . . . . . . BTM 65 A . . . . . . . . . . . . . . . . . . . . . . BTM 65 A/HC . . . . . . . . . . . . . . . . . . . BTM 65 B . . . . . . . . . . . . . . . . . . . . . . BTM 65 B/HC . . . . . . . . . . . . . . . . . . . BTM 70 A . . . . . . . . . . . . . . . . . . . . . . BTM 70 A/HC . . . . . . . . . . . . . . . . . . . BTM 70 B . . . . . . . . . . . . . . . . . . . . . . BTM 70 B/HC . . . . . . . . . . . . . . . . . . . BTM 80 A . . . . . . . . . . . . . . . . . . . . . . BTM 80 A/HC . . . . . . . . . . . . . . . . . . . BTM 80 B . . . . . . . . . . . . . . . . . . . . . . BTM 80 B/HC . . . . . . . . . . . . . . . . . . . BTM 85 A . . . . . . . . . . . . . . . . . . . . . . BTM 85 A/HC . . . . . . . . . . . . . . . . . . . BTM 85 B . . . . . . . . . . . . . . . . . . . . . . BTM 85 B/HC . . . . . . . . . . . . . . . . . . . BTM 90 A . . . . . . . . . . . . . . . . . . . . . .
AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
252 252 252 252 252 252 252 252 252 252 252 252 228 230 228 230 228 230 228 230 228 230 228 230 228 230 228 230 226 230 226 230 226 230 226 230 226 230 226 230 226 230 226 230 226 230 226 230 226
BTM 90 A/HC . . . . . . . . . . . . . . . . . . . BTM 90 B . . . . . . . . . . . . . . . . . . . . . . BTM 90 B/HC . . . . . . . . . . . . . . . . . . . FBSA 204/QBCA. . . . . . . . . . . . . . . . . FBSA 204/QFCA. . . . . . . . . . . . . . . . . FBSD 25/QBCA . . . . . . . . . . . . . . . . . FBSD 25/QFCA. . . . . . . . . . . . . . . . . . FBSD 30/QBCA . . . . . . . . . . . . . . . . . FBSD 30/QFCA. . . . . . . . . . . . . . . . . . FBSD 35/QBCA . . . . . . . . . . . . . . . . . FBSD 35/QFCA. . . . . . . . . . . . . . . . . . FBSD 40/QBCA . . . . . . . . . . . . . . . . . FBSD 40/QFCA. . . . . . . . . . . . . . . . . . FBSD 45/QBCA . . . . . . . . . . . . . . . . . FBSD 45/QFCA. . . . . . . . . . . . . . . . . . FBSD 50/QBCA . . . . . . . . . . . . . . . . . FBSD 50/QFCA. . . . . . . . . . . . . . . . . . FBSD 55/QBCA . . . . . . . . . . . . . . . . . FBSD 55/QFCA. . . . . . . . . . . . . . . . . . FBSD 60/QBCA . . . . . . . . . . . . . . . . . FBSD 60/QFCA. . . . . . . . . . . . . . . . . . GB 3006 . . . . . . . . . . . . . . . . . . . . . . . GB 3007 . . . . . . . . . . . . . . . . . . . . . . . GB 3008 . . . . . . . . . . . . . . . . . . . . . . . GB 3009 . . . . . . . . . . . . . . . . . . . . . . . GB 3010 . . . . . . . . . . . . . . . . . . . . . . . GB 3011 . . . . . . . . . . . . . . . . . . . . . . . GB 3012 . . . . . . . . . . . . . . . . . . . . . . . GB 3013 . . . . . . . . . . . . . . . . . . . . . . . GB 3014 . . . . . . . . . . . . . . . . . . . . . . . GB 3015 . . . . . . . . . . . . . . . . . . . . . . . GB 3016 . . . . . . . . . . . . . . . . . . . . . . . GB 3017 . . . . . . . . . . . . . . . . . . . . . . . GB 3018 . . . . . . . . . . . . . . . . . . . . . . . GB 3019 . . . . . . . . . . . . . . . . . . . . . . . GB 3020 . . . . . . . . . . . . . . . . . . . . . . . GB 3021 . . . . . . . . . . . . . . . . . . . . . . . GB 3022 . . . . . . . . . . . . . . . . . . . . . . . GB 3024 . . . . . . . . . . . . . . . . . . . . . . . GB 3026 . . . . . . . . . . . . . . . . . . . . . . . GB 3028 . . . . . . . . . . . . . . . . . . . . . . . GB 3030 . . . . . . . . . . . . . . . . . . . . . . . GB 3032 . . . . . . . . . . . . . . . . . . . . . . . GB 3034 . . . . . . . . . . . . . . . . . . . . . . . GB 3036 . . . . . . . . . . . . . . . . . . . . . . . GB 3038 . . . . . . . . . . . . . . . . . . . . . . . GB 3040 . . . . . . . . . . . . . . . . . . . . . . . GB 4920 . . . . . . . . . . . . . . . . . . . . . . . GB 4921 . . . . . . . . . . . . . . . . . . . . . . .
HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . AT2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HT2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GBA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
230 226 230 254 254 254 254 254 254 254 254 254 254 254 254 254 254 256 256 256 256 291 291 291 291 291 291 291 291 291 291 291 291 291 291 291 292 292 292 292 292 292 292 292 292 292 292 295 295
312
313
9
9
Products index
Designation
Code
Page
Designation . . . . . . . . . . . . . . . . . . . . Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page
GB 4922 . . . . . . . . . . . . . . . . . . . . . . . GB 4924 . . . . . . . . . . . . . . . . . . . . . . . GB 4926 . . . . . . . . . . . . . . . . . . . . . . . GB 4928 . . . . . . . . . . . . . . . . . . . . . . . GB 4930 . . . . . . . . . . . . . . . . . . . . . . . GB 4932 . . . . . . . . . . . . . . . . . . . . . . . GB 4934 . . . . . . . . . . . . . . . . . . . . . . . GB 4936 . . . . . . . . . . . . . . . . . . . . . . . GB 4938 . . . . . . . . . . . . . . . . . . . . . . . GB 4940 . . . . . . . . . . . . . . . . . . . . . . . GB 4944 . . . . . . . . . . . . . . . . . . . . . . . GB 4948 . . . . . . . . . . . . . . . . . . . . . . . GB 4952 . . . . . . . . . . . . . . . . . . . . . . . GB 4956 . . . . . . . . . . . . . . . . . . . . . . . GRA 3005 . . . . . . . . . . . . . . . . . . . . . . GRA 3006 . . . . . . . . . . . . . . . . . . . . . . GRA 3007 . . . . . . . . . . . . . . . . . . . . . . GRA 3008 . . . . . . . . . . . . . . . . . . . . . . GRA 3009 . . . . . . . . . . . . . . . . . . . . . . GRA 3010 . . . . . . . . . . . . . . . . . . . . . . GRA 3011 . . . . . . . . . . . . . . . . . . . . . . GRA 3012 . . . . . . . . . . . . . . . . . . . . . . GRA 3013 . . . . . . . . . . . . . . . . . . . . . . GRA 3014 . . . . . . . . . . . . . . . . . . . . . . GRA 3015 . . . . . . . . . . . . . . . . . . . . . . GRA 3016 . . . . . . . . . . . . . . . . . . . . . . GRA 3017 . . . . . . . . . . . . . . . . . . . . . . GRA 3018 . . . . . . . . . . . . . . . . . . . . . . GRA 3019 . . . . . . . . . . . . . . . . . . . . . . GRA 3020 . . . . . . . . . . . . . . . . . . . . . . GRA 3021 . . . . . . . . . . . . . . . . . . . . . . GRA 3022 . . . . . . . . . . . . . . . . . . . . . . GRA 3024 . . . . . . . . . . . . . . . . . . . . . . GRA 3026 . . . . . . . . . . . . . . . . . . . . . . GRA 3028 . . . . . . . . . . . . . . . . . . . . . . GRA 3030 . . . . . . . . . . . . . . . . . . . . . . GRA 3032 . . . . . . . . . . . . . . . . . . . . . . GRA 3034 . . . . . . . . . . . . . . . . . . . . . . GRA 3036 . . . . . . . . . . . . . . . . . . . . . . GRA 3038 . . . . . . . . . . . . . . . . . . . . . . GRA 3040 . . . . . . . . . . . . . . . . . . . . . . KMT 0 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 1 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 10 . . . . . . . . . . . . . . . . . . . . . . . . KMT 11 . . . . . . . . . . . . . . . . . . . . . . . . KMT 12 . . . . . . . . . . . . . . . . . . . . . . . . KMT 13 . . . . . . . . . . . . . . . . . . . . . . . . KMT 14 . . . . . . . . . . . . . . . . . . . . . . . .
GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA GBA KMT KMT KMT KMT KMT KMT KMT
295 295 295 295 295 295 295 295 295 295 295 295 295 295 288 288 288 288 288 288 288 288 288 288 288 288 288 288 288 288 288 288 289 289 289 289 289 289 289 289 289 266 266 266 266 266 266 266
KMT 15 . . . . . . . . . . . . . . . . . . . . . . . . KMT 16 . . . . . . . . . . . . . . . . . . . . . . . . KMT 17 . . . . . . . . . . . . . . . . . . . . . . . . KMT 18 . . . . . . . . . . . . . . . . . . . . . . . . KMT 19 . . . . . . . . . . . . . . . . . . . . . . . . KMT 2 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 20 . . . . . . . . . . . . . . . . . . . . . . . . KMT 21 . . . . . . . . . . . . . . . . . . . . . . . . KMT 22 . . . . . . . . . . . . . . . . . . . . . . . . KMT 24 . . . . . . . . . . . . . . . . . . . . . . . . KMT 26 . . . . . . . . . . . . . . . . . . . . . . . . KMT 28 . . . . . . . . . . . . . . . . . . . . . . . . KMT 3 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 30 . . . . . . . . . . . . . . . . . . . . . . . . KMT 32 . . . . . . . . . . . . . . . . . . . . . . . . KMT 34 . . . . . . . . . . . . . . . . . . . . . . . . KMT 36 . . . . . . . . . . . . . . . . . . . . . . . . KMT 38 . . . . . . . . . . . . . . . . . . . . . . . . KMT 4 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 40 . . . . . . . . . . . . . . . . . . . . . . . . KMT 5 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 6 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 7 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 8 . . . . . . . . . . . . . . . . . . . . . . . . . KMT 9 . . . . . . . . . . . . . . . . . . . . . . . . . KMTA 10 . . . . . . . . . . . . . . . . . . . . . . . KMTA 11 . . . . . . . . . . . . . . . . . . . . . . . KMTA 12 . . . . . . . . . . . . . . . . . . . . . . . KMTA 13 . . . . . . . . . . . . . . . . . . . . . . . KMTA 14 . . . . . . . . . . . . . . . . . . . . . . . KMTA 15 . . . . . . . . . . . . . . . . . . . . . . . KMTA 16 . . . . . . . . . . . . . . . . . . . . . . . KMTA 17 . . . . . . . . . . . . . . . . . . . . . . . KMTA 18 . . . . . . . . . . . . . . . . . . . . . . . KMTA 19 . . . . . . . . . . . . . . . . . . . . . . . KMTA 20 . . . . . . . . . . . . . . . . . . . . . . . KMTA 21 . . . . . . . . . . . . . . . . . . . . . . . KMTA 22 . . . . . . . . . . . . . . . . . . . . . . . KMTA 24 . . . . . . . . . . . . . . . . . . . . . . . KMTA 26 . . . . . . . . . . . . . . . . . . . . . . . KMTA 28 . . . . . . . . . . . . . . . . . . . . . . . KMTA 30 . . . . . . . . . . . . . . . . . . . . . . . KMTA 32 . . . . . . . . . . . . . . . . . . . . . . . KMTA 34 . . . . . . . . . . . . . . . . . . . . . . . KMTA 36 . . . . . . . . . . . . . . . . . . . . . . . KMTA 38 . . . . . . . . . . . . . . . . . . . . . . . KMTA 40 . . . . . . . . . . . . . . . . . . . . . . . KMTA 5 . . . . . . . . . . . . . . . . . . . . . . . . KMTA 6 . . . . . . . . . . . . . . . . . . . . . . . .
314
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT KMT
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
266 266 266 266 266 266 266 266 266 266 266 268 266 268 268 268 268 268 266 268 266 266 266 266 266 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 270 272 272 272 272 270 270 315
9
9
Products index
Designation . . . . . . . . . . . . . . . . . . . . Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page
Designation . . . . . . . . . . . . . . . . . . . . Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page
KMTA 7 . . . . . . . . . . . . . . . . . . . . . . . . KMTA 8 . . . . . . . . . . . . . . . . . . . . . . . . KMTA 9 . . . . . . . . . . . . . . . . . . . . . . . . N 1008 K . . . . . . . . . . . . . . . . . . . . . . . N 1008 K/HC5 . . . . . . . . . . . . . . . . . . . N 1009 K . . . . . . . . . . . . . . . . . . . . . . . N 1009 K/HC5 . . . . . . . . . . . . . . . . . . . N 1010 K . . . . . . . . . . . . . . . . . . . . . . . N 1010 K/HC5 . . . . . . . . . . . . . . . . . . . N 1011 K . . . . . . . . . . . . . . . . . . . . . . . N 1011 K/HC5 . . . . . . . . . . . . . . . . . . . N 1012 K . . . . . . . . . . . . . . . . . . . . . . . N 1012 K/HC5 . . . . . . . . . . . . . . . . . . . N 1013 K . . . . . . . . . . . . . . . . . . . . . . . N 1013 K/HC5 . . . . . . . . . . . . . . . . . . . N 1014 K . . . . . . . . . . . . . . . . . . . . . . . N 1014 K/HC5 . . . . . . . . . . . . . . . . . . . N 1015 K . . . . . . . . . . . . . . . . . . . . . . . N 1015 K/HC5 . . . . . . . . . . . . . . . . . . . N 1016 K . . . . . . . . . . . . . . . . . . . . . . . N 1016 K/HC5 . . . . . . . . . . . . . . . . . . . N 1017 K . . . . . . . . . . . . . . . . . . . . . . . N 1017 K/HC5 . . . . . . . . . . . . . . . . . . . N 1018 K . . . . . . . . . . . . . . . . . . . . . . . N 1018 K/HC5 . . . . . . . . . . . . . . . . . . . N 1019 K . . . . . . . . . . . . . . . . . . . . . . . N 1019 K/HC5 . . . . . . . . . . . . . . . . . . . N 1020 K . . . . . . . . . . . . . . . . . . . . . . . N 1020 K/HC5 . . . . . . . . . . . . . . . . . . . N 1021 K . . . . . . . . . . . . . . . . . . . . . . . N 1021 K/HC5 . . . . . . . . . . . . . . . . . . . N 1022 K . . . . . . . . . . . . . . . . . . . . . . . N 1022 K/HC5 . . . . . . . . . . . . . . . . . . . N 1024 K . . . . . . . . . . . . . . . . . . . . . . . N 1024 K/HC5 . . . . . . . . . . . . . . . . . . . NN 3005 . . . . . . . . . . . . . . . . . . . . . . . NN 3005 K. . . . . . . . . . . . . . . . . . . . . . NN 3006 . . . . . . . . . . . . . . . . . . . . . . . NN 3006 K. . . . . . . . . . . . . . . . . . . . . . NN 3007 . . . . . . . . . . . . . . . . . . . . . . . NN 3007 K. . . . . . . . . . . . . . . . . . . . . . NN 3008 . . . . . . . . . . . . . . . . . . . . . . . NN 3008 K. . . . . . . . . . . . . . . . . . . . . . NN 3009 . . . . . . . . . . . . . . . . . . . . . . . NN 3009 K. . . . . . . . . . . . . . . . . . . . . . NN 3010 . . . . . . . . . . . . . . . . . . . . . . . NN 3010 K. . . . . . . . . . . . . . . . . . . . . . NN 3011 . . . . . . . . . . . . . . . . . . . . . . . NN 3011 K. . . . . . . . . . . . . . . . . . . . . .
NN 3012 . . . . . . . . . . . . . . . . . . . . . . . NN 3012 K. . . . . . . . . . . . . . . . . . . . . . NN 3013 . . . . . . . . . . . . . . . . . . . . . . . NN 3013 K. . . . . . . . . . . . . . . . . . . . . . NN 3014 . . . . . . . . . . . . . . . . . . . . . . . NN 3014 K. . . . . . . . . . . . . . . . . . . . . . NN 3015 . . . . . . . . . . . . . . . . . . . . . . . NN 3015 K. . . . . . . . . . . . . . . . . . . . . . NN 3016 . . . . . . . . . . . . . . . . . . . . . . . NN 3016 K. . . . . . . . . . . . . . . . . . . . . . NN 3017 . . . . . . . . . . . . . . . . . . . . . . . NN 3017 K. . . . . . . . . . . . . . . . . . . . . . NN 3018 . . . . . . . . . . . . . . . . . . . . . . . NN 3018 K. . . . . . . . . . . . . . . . . . . . . . NN 3019 . . . . . . . . . . . . . . . . . . . . . . . NN 3019 K. . . . . . . . . . . . . . . . . . . . . . NN 3020 . . . . . . . . . . . . . . . . . . . . . . . NN 3020 K. . . . . . . . . . . . . . . . . . . . . . NN 3021 . . . . . . . . . . . . . . . . . . . . . . . NN 3021 K. . . . . . . . . . . . . . . . . . . . . . NN 3022 . . . . . . . . . . . . . . . . . . . . . . . NN 3022 K. . . . . . . . . . . . . . . . . . . . . . NN 3024 . . . . . . . . . . . . . . . . . . . . . . . NN 3024 K. . . . . . . . . . . . . . . . . . . . . . NN 3026 . . . . . . . . . . . . . . . . . . . . . . . NN 3026 K. . . . . . . . . . . . . . . . . . . . . . NN 3028 K. . . . . . . . . . . . . . . . . . . . . . NN 3030 K. . . . . . . . . . . . . . . . . . . . . . NN 3032 K. . . . . . . . . . . . . . . . . . . . . . NN 3034 K. . . . . . . . . . . . . . . . . . . . . . NN 3036 K. . . . . . . . . . . . . . . . . . . . . . NN 3038 K. . . . . . . . . . . . . . . . . . . . . . NN 3040 K. . . . . . . . . . . . . . . . . . . . . . NN 3044 K. . . . . . . . . . . . . . . . . . . . . . NN 3048 K. . . . . . . . . . . . . . . . . . . . . . NN 3052 K. . . . . . . . . . . . . . . . . . . . . . NN 3056 K. . . . . . . . . . . . . . . . . . . . . . NNU 4920 BK/W33 . . . . . . . . . . . . . . . NNU 4920 B/W33 . . . . . . . . . . . . . . . . NNU 4921 BK/W33 . . . . . . . . . . . . . . . NNU 4921 B/W33 . . . . . . . . . . . . . . . . NNU 4922 BK/W33 . . . . . . . . . . . . . . . NNU 4922 B/W33 . . . . . . . . . . . . . . . . NNU 4924 BK/W33 . . . . . . . . . . . . . . . NNU 4924 B/W33 . . . . . . . . . . . . . . . . NNU 4926 BK/W33 . . . . . . . . . . . . . . . NNU 4926 B/W33 . . . . . . . . . . . . . . . . NNU 4928 BK/W33 . . . . . . . . . . . . . . . NNU 4928 B/W33 . . . . . . . . . . . . . . . .
316
KMT KMT KMT SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC1 HC1 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
270 270 270 204 208 204 208 204 208 204 208 204 208 204 208 204 208 204 208 204 208 204 208 204 208 204 208 206 210 206 210 206 210 206 210 196 196 196 196 196 196 196 196 196 196 196 196 196 196
SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
196 196 196 196 196 196 196 196 196 196 198 198 198 198 198 198 198 198 198 198 198 198 198 198 198 198 200 200 200 200 200 200 200 200 200 202 202 198 198 198 198 198 198 198 198 198 198 200 200 317
9
9 Products index
Designation . . . . . . . . . . . . . . . . . . . . Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page NNU 4930 BK/W33 . . . . . . . . . . . . . . . NNU 4930 B/W33 . . . . . . . . . . . . . . . . NNU 4932 BK/W33 . . . . . . . . . . . . . . . NNU 4932 B/W33 . . . . . . . . . . . . . . . . NNU 4934 BK/W33 . . . . . . . . . . . . . . . NNU 4934 B/W33 . . . . . . . . . . . . . . . . NNU 4936 BK/W33 . . . . . . . . . . . . . . . NNU 4936 B/W33 . . . . . . . . . . . . . . . . NNU 4938 BK/W33 . . . . . . . . . . . . . . . NNU 4938 B/W33 . . . . . . . . . . . . . . . . NNU 4940 BK/W33 . . . . . . . . . . . . . . . NNU 4940 B/W33 . . . . . . . . . . . . . . . . NNU 4944 BK/W33 . . . . . . . . . . . . . . . NNU 4944 B/W33 . . . . . . . . . . . . . . . . NNU 4948 BK/W33 . . . . . . . . . . . . . . . NNU 4948 B/W33 . . . . . . . . . . . . . . . . NNU 4952 BK/W33 . . . . . . . . . . . . . . . NNU 4952 B/W33 . . . . . . . . . . . . . . . . NNU 4956 BK/W33 . . . . . . . . . . . . . . . NNU 4956 B/W33 . . . . . . . . . . . . . . . .
318
SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2 SC2
.............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. .............................. ..............................
200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 202 202 202 202
