Accessories B-3-1.6 Accessories Accessories to use with NSK ball screws are available. Table 1 Support unit categories Application
Shape
Support side
Bearing in use
Bearing bore, Bearing
Page
Application
Shape
Support side
Bearing in use
seat diameter
WBK**R-11 (Support kit) j6 – j25
WBK**S-01* Deep groove ball bearing
j6 – j25
Deep groove ball bearing (arranged to have angular contact)
B381 –
Small equipment, Round light load
Small equipment, Square light load
Page
seat diameter
WBK**-01* Fixed support Angular contact side ball bearing
Bearing bore, Bearing
Fixed support side
B387
j4, j6 (exclusive for RMA and RMS types)
WBK**-11*
B385 –
Angular contact ball bearing
j6 – j25
B383 –
Thrust angular contact ball bearing
j17 – j40
B391 –
Simple support side WBK**DF*-31 Deep groove ball bearing
j12, j15
B388
Machine Round tools, heavy load
Fixed support side
Support unit
WBK**SF-01
(exclusive for VFA type)
1. Classification Ball screw support units are classified into categories by their shape (Table 1). Select the type that best suits your particular needs.
B375
B375-386.indd 375-376
2. Features ABearings and seals On the fixed support side, the angular contact ball bearing is used. It has great rigidity and low friction torque, which match the rigidity of the ball screw. The thrust angular contact ball bearing with high precision and great rigidity is another choice for the fixed support side. An oil seal is installed to the fixed support side used with an angular contact ball bearing. Fine clearance may occur with this seal. A deep-groove ball bearing with a shield on both sides is used on the simple support side.
ALock nut is provided. A lock nut with fine grade finish is provided to fix the bearing with high precision.
B376
9/19/12 3:31:11 PM
Accessories
3. Reference number coding
(1) Support Units for Light Load and Small Equipment
(For light load) Example:
WBK 08 S - 01 A
Product code for support unit
No code or A: For general use B: Low-profile type (only for square type) C: For clean environment use
Nominal size code* Mounting code No code: Fixed support unit S: Simple support unit SF: Simple support unit (for FSS and VFA) R: Fixed support unit (support kit for miniature ball screws)
01: Square type 11: Round type
*) In case of simple support unit, please note that the nominal size code of 12 or less does not strictly represent internal bore of bearing in millimeters. Please refer to the dimensional table for internal bore of bearing.
Support units for light load and small equipment provide both fixed and support side bearing assemblies to support screw shafts. They provide all required parts such as bearing locknuts so that you can mount them directly to NSK standard ball screws, of which shaft ends are machined. Please refer to the dimensions listed on the dimension table for the configuration of standard screw shaft ends for NSK standard ball screws with blank shaft ends. For ball screws for transfer equipment, you require optional spacers when mounting fixed support side support units.
(a) Features APrompt delivery All support units are standard products. ABest selection of bearings for your application General use support units for fixed support side are equipped with highly rigid angular contact ball bearings that have been assembled with proper preload, and packed with the appropriate volume of grease. On the other hand, clean support units for fixed support side uses low dust emission grease, and low torque special bearings. Sealed deep groove ball bearings are used for simple support side units for both general and clean environment use.
Support unit
(For heavy load) Example:
WBK 25 DF - 31
Product code for support unit Nominal size code (internal bore of bearing)
Bearing combination code DF: Face to face duplex combination DFD: Face to face triplex combination DFF: Face to face quadruplex combination
B377
B375-386.indd 377-378
B378
9/19/12 3:31:13 PM
Accessories
4, 3
2
5
1
6
7
WBK10-01A
1 000
ALow torque It features low torque characteristics because of special bearings. (50% lower than general support unit.) AHigh antirust specification Low temperature chrome plating is applied to bearing housings, retaining plates, locknuts and spacers to improve antirust properties. Moreover, bolts and snap rings are made of stainless steel. The table below shows the surface treatment of the bearing housing and material of small parts.
Particle size: 0.1 μm or over, rotational speed: 1 000 min-1
10 000
Particle count no./cf
(b) Features of Clean Support Unit AOutstanding low dust emission Clean support unit uses "NSK clean grease LG2" which has a proven feature of low dust emission. It reduces dust emission to 1/10 of general support units.
WBK10-01C
100
10
1
0
50
100
150
200
250
Time, hr
Rotational speed: 10 min-1
3 Dynamic torque, Ns cm
* Do not disassemble fixed support side units as they are equipped with bearings and oil seals.
AAccessories Support units provide everything necessary for mounting ball screws to machines. (Please refer to the table below.)
WBK10-01A
WBK10-01C
2 1 0 —1 —2 —3
0
5
10
15
30
35
40
45
Support unit
20 25 Time, sec
Clean support unit Bearing • grease Surface treatment Set screw and snap ring material
AAntirust treatment The table on the right shows the surface treatment for the bearing housing, and material of small parts.
Fixed support side Part No.
Name of parts
Stainless steel
Name of parts
Bearing housing
5
Bearing housing
2
Spacer
6
Bearing
Locknut
7
Snap ring
4
Low temperature chrome plating
Simple support side Part No.
1 3
Special bearings, LG2
Set screw with brass pad
General support unit Bearings and grease Surface treatment Screws and snap rings
B379
B375-386.indd 379-380
Angular contact ball bearings, PS2 Black oxide Standard material
B380
9/19/12 3:31:13 PM
Accessories
Support Unit (Support Units for Light Load and Small Equipment)
Support Units for Light Load and Small Equipment
T
U
S
d1
Set screw Brass pad
Reference No.
M 2-jX drill thru
N K
E cF
H
J
S
Retaining cover Set screw
D
Locknut
Set screw
WBK04-**
100
69 (M3)
WBK06-**
190
69 (M3)
WBK08-**
230
69 (M3)
WBK10-**
280
147 (M4)
WBK12-**
630
147 (M4)
WBK15-**
790
147 (M4)
WBK17-**
910
147 (M4)
WBK20-**
1670
147 (M4)
WBK25-**
2060
490 (M6)
0
C - 0.05
B
jd1
Brass pad
Tightening torque (reference) [N·cm]
M 2-jX drill thru jY c’bore, Z deep
N
W A
A
L K
J
View S (WBK06 – 15)
Fixed support side support unit (square type)
Use
d1
A
B
Q
P
Q
View S (WBK17 – 25) Units: mm
C
D
E
F
L
J
K
R
T
U
Mass
Counterbore dimensions
N
(kg)
Locknut screw M
Attached bearing for support side
H
P
Q
W
X
Y
Z
WBK04-01M
General
4
27
17
10
6
14
10
—
14
5.5
7
9
1.5
2
7
—
—
21
3.5
—
—
0.03
M4×0.5
—
WBK06-01M
General
6
35
22.5
13
8
19
12
—
17
7.5
9.5
12
2.5
2.5
8.5
—
—
26
5.5
—
—
0.05
M6×0.75
—
*1
General
6
12
20
20
5.5
—
—
—
3.5
10
—
—
30
5.5
9.5
11
0.15
M6×0.75
WBK08-01A*1
General
23
23
7
4
11.5
38
6.6
11
12
0.25
21.5
25.5
4.5
23
23
7
24
30
5.5
WBK06-01A WBK08-01B
WBK08-01C*1
Low type
8
Clean environment
WBK10-01A
General
WBK10-01B
Low type
WBK10-01C
Clean environment
WBK12-01A
General
WBK12-01B
Low type
WBK12-01C
Clean environment
10
12
42
25
13
20
18
52
32
17
26
25
62
31
15.5
31
—
52
32
17
26
25
43
25
35
36
38
20
38
—
43
25
35
36
43
25
35
36
38
20
38
—
43
25
35
36
50
30
40
41
42
22
42
—
50
30
40
41
70
70
14
17
19
24
30
5.5
—
—
—
—
—
—
—
—
—
3.5
11
4
11.5
6
12
6
12
—
—
—
—
—
—
46
9
14
18
0.3
38
6.6
11
12
0.25
52
9
14
52
9
14
11
0.5
19
0.45
11
0.5
11
0.5
19
0.4
11
0.5
15
0.7
23
0.6
15
0.7
— 606ZZ
M8×1
606ZZ 606VV 608ZZ
M10×1
608ZZ 608VV 6000ZZ
M12×1
6000ZZ 6000VV 6002ZZ
WBK15-01A
General
WBK15-01B
Low type
WBK15-01C
Clean environment
WBK17-01A
General
17
86
64
39
55
50
24
35
44
7
—
—
—
7
—
19
8
68
9
14
11
1.3
M17×1
6203ZZ
WBK20-01
General
20
95
58
30
45
56
30
42
52
10
—
—
—
10
—
22
10
75
11
17
15
1.4
M20×1
6204ZZ
General
25
105
68
35
25
66
36
48
61
13
—
—
—
14
—
30
9
85
11
—
—
1.9
M25×1.5
6205ZZ
WBK25-01*2 WBK25-01W*2
15
80
22
25
31
12
—
Notes: 1. Use datum surface A for mounting to machine base. 2. Tighten set screw after locknut has been adjusted and tightened. 3. Insert brass pad provided with unit into locknut set screw hole, then insert and tighten the set screw. 4. Deep groove ball bearing and snap ring are also provided for simple support side. (except WBK04-01M and WBK06-01M) B381
B375-386.indd 381-382
—
—
5
12.5
—
—
60
11
17
Support unit
Reference No.
4-jX drill thru jY c’bore, Z deep
H
M15×1
6002ZZ 6002VV
5. Bearings for WBK04-01M and WBK06-01M are equipped with non-contact metal seal. *1) For retaining cover side of WBK06-01A, WBK08-01A, and WBK08-01C, there are no seals. *2) WBK25-01W is standard.
B382
9/19/12 3:31:14 PM
Accessories
Support Unit (Support Units for Light Load and Small Equipment) 4-jX drill thru.
X
L
Set screw
QP
K
Set screw
Brass pad
Set piece
DW d1
jD1 g6
d1
jD2
PC
Tightening torque (reference) [N·cm]
j
C
Reference No. X J
cU
H
F
A
K
J
Q P
Set screw
Retaining cover
Locknut
Set screw
WBK04-**
100
69 (M3)
WBK06-**
190
69 (M3)
WBK08-**
230
69 (M3)
WBK10-**
280
147 (M4)
630
147 (M4)
WBK15-**
790
147 (M4)
Brass pad
WBK17-**
910
147 (M4)
WBK20-**
1670
147 (M4)
WBK25-**
2060
490 (M6)
X
WBK12-**
Set screw
Retaining cover
jd1
jd1
jD1g 6
Set piece
cU
4-jX drill thru. jY c’bore, Z deep PCD W
H
E
L
45°
N
M
jC
X
A/2
A/2
H
J F
cA
N
J
H
E
View X-X (example 1)
View X-X (example 2)
Reference No.
Use
d1
A
Units: mm
C
D1
D2
E
H
L
K
F
N
U
P
Mass
Counterbore dimensions
Q
Locknut screw M
Attached bearing for support side
J
W
X
Y
Z
(kg)
WBK04-11M
General
4
14
26
14
14
13.5
8.5
7
1.5
5.5
6.6
10
2.6
2.4
3
20
3.5
—
—
0.02
M4×0.5
—
WBK06-11M
General
6
19
34
19
18.5
17
12
9.5
2.5
7.5
8
12
3
2
4
26
4.5
—
—
0.04
M6×0.75
—
WBK06-11*
General
6
28
35
22
—
12
4.5
2.5
3.5
0.1
M6×0.75
WBK08-11B
High-load type
42
52
34
35
43
28
10
42
52
34
12
44
54
15
52
WBK08-11* WBK08-11C* WBK10-11 WBK10-11C WBK12-11 WBK12-11C WBK15-11 WBK15-11C
General
8
Clean environment General Clean environment General Clean environment General Clean environment
7
28
2.9
5.5
10
42
4.5
8
9
35
3.4
6.5
4
10
42
4.5
8
4
0.2
M10×1
6
4
10
44
4.5
8
4
0.25
M12×1
8
7
15
50
5.5
9.5
6
0.4
M15×1
20
13
9.5
3.5
5.5
6.5
25.5
15.5
12
3.5
4.5
7
23
14
10
4
7
8
—
27
17
12
5
7.5
8.5
17
6
36
—
27
17
12
5
7.5
8.5
19
63
40
—
32
17
11
6
12
14
22
—
6 14
5
4
0.2 4
0.15
— 606ZZ
M8×1
606ZZ 606VV 608ZZ 608VV 6000ZZ 6000VV 6002ZZ 6002VV
WBK20-11
General
20
68
85
57
—
52
30
20
10
10
14
30
14
8
22
70
6.6
11
10
1.1
M20×1
6204ZZ
WBK25-11
General
25
79
98
63
—
57
30
20
10
13
20
36
17
10
27
80
9
15
13
1.5
M25×1.5
6205ZZ
Notes: 1. Tighten set screw after locknut has been adjusted and tightened. 2. Insert brass pad provided with unit into locknut set screw hole, then insert and tighten the set screw. 3. Deep groove ball bearing and snap ring are also provided for simple support side. (except WBK04-01M and WBK06-01M)
B383
B375-386.indd 383-384
Support unit
Fixed support side support unit (round type)
4. Bearings for WBK04-01M and WBK06-01M are equipped with non-contact metal seal. *For retaining cover side of WBK06-01A, WBK08-01A, and WBK08-01C, there are no seals.
B384
9/19/12 3:31:15 PM
Accessories
Support Unit (Support Units for Light Load and Small Equipment) Specifications of support unit Fixed support side support unit
Simple support side support unit Maximum Radial direction Bearing Basic dynamic load starting Reference No. Basic dynamic load Load limit Rigidity reference No. rating torque [N] rating Ca [N] [N/μm] [N·cm] C [N] Axial direction
E
jd 1
0 C –0.05
D
B
jd 2
2-jX drill thru. jY c’bore, Z deep
R/2 R/2 R
W A
B
Reference No.
Use
WBK04-01M
General
1 470
464
39
0.2
—
—
WBK04-11M
General
1 470
464
39
0.2
—
—
—
WBK06-01A
General
2 670
1 040
28
0.49
—
—
—
WBK06-01M
General
2 760
854
60
0.35
—
—
—
WBK06-11
General
2 670
1 040
28
0.49
—
—
—
WBK06-11M
General
2 760
854
60
0.35
WBK08-01A
General
4 400
1 450
49
0.88
WBK08S-01
WBK08-01B
Low type
6 600
2 730
94
1.9
WBK08S-01B
—
WBK12SF-01B
Simple support side support unit (square type)
Reference No.
General
WBK08S-01B
Low type
WBK08S-01C
Clean environment
WBK10S-01
General
WBK10S-01C
Clean environment
WBK12S-01
A 52
6
8
Low type
WBK12S-01C
Clean environment
WBK12SF-01B WBK15S-01
Low type
10 12
Low type
WBK15S-01C
Clean environment
WBK15SF-01B WBK17S-01
Low type General
WBK20S-01
General
WBK20SF-01B
15
Low type
17 20
C
D
25
R 15
Counterbore dimensions
Mass
W
X
Y
Z
(kg)
38
6.6
11
12
0.15
*
WBK25SF-01
General
25
B375-386.indd 385-386
3 100
1 100
36
0.52
WBK08S-01C
606VV
2 260
WBK08-11
General
4 400
1 450
49
0.88
WBK08S-01
606ZZ
2 260
Low type
6 600
2 730
94
1.9
—
606ZZ
2 260
WBK08-11C Clean environment
3 100
1 100
36
0.52
WBK08S-01C
606VV
2 260
WBK10-01A
6 600
2 730
94
1.9
WBK10S-01
608ZZ
3 300
WBK12SF-01*2
6001ZZ
5 100
WBK08-11B
WBK10-01B
General Low type
6 600
2 730
94
1.9
—
608ZZ
3 300
WBK10-01C Clean environment
4 250
1 364
50
1.1
WBK10S-01C
608VV
3 300
31
15.5
31
—
16
46
9
14
18
0.2
WBK10-11
6 600
2 730
94
1.9
WBK10S-01
608ZZ
3 300
32
17
26
25
15
38
6.6
11
12
0.15
WBK10-11C Clean environment
4 250
1 364
50
1.1
WBK10S-01C
608VV
3 300
WBK12-01A
7 100
3 040
104
2.1
WBK12S-01
6000ZZ
4 550
*2
6902ZZ
4 350
WBK12S-01B
6000ZZ
4 550
43
25
35
36
43
25
35
36
38
20
38
—
43
25
35
36
31
15.5
31
—
50
30
40
41
42
22
42
—
50
30
40
41
70
38
20
38
—
18
52
86
64
39
55
50
23
68
95
58
30
45
56
26
75
80
42
22
42
—
22
60
70 62 80
20
20 18 20
52
52
9
9
14
14
46 60
9
14
9
14
11
17
General General
11
0.4
11
0.35
19
0.4
11
0.35
WBK12-01C Clean environment
4 700
WBK15SF-01 WBK12-01B
Low type
7 100
3 040
104
2.1
WBK15SF-01B 57
1.2
WBK12S-01C
6902ZZ
4 350
6000VV
4 550
18
0.2
WBK12-11
7 100
3 040
104
2.1
WBK12S-01
6000ZZ
4 550
0.45
WBK12-11C Clean environment
4 700
2 443
57
1.2
WBK12S-01C
6000VV
4 550
23
0.4
WBK15-01A
General
7 600
3 380
113
2.4
WBK15S-01
6002ZZ
5 600
11
0.45
WBK15-01B
Low type
7 600
3 380
113
2.4
WBK15S-01B
6002ZZ
5 600
19
0.3
11
0.8
WBK15-01C Clean environment
5 100
15
0.8
WBK15-11
23
0.4
WBK15-11C Clean environment WBK17-01A
68
35
25
66
30
85
11
—
—
0.9
95
58
30
45
56
22
75
11
17
15
0.55
General
2 443
*1
11
105
Notes: 1. Use datum surface B for mounting to machine base. *) WBK25-01W is standard.
B385
1 920
WBK08-01C Clean environment
62
*
WBK25S-01W
2 260
52 70
26
E
606ZZ 6801ZZ
17
General
WBK15S-01B
B
— 2 260
32
General
WBK12S-01B
WBK25S-01
d2
*1
— 606ZZ
WBK20SF-01B*1 6804ZZ
4 000
1.3
WBK15S-01C
6002VV
5 600
2 757
63
7 600
3 380
113
2.4
WBK15S-01
6002ZZ
5 600
5 100
2 757
63
1.3
WBK15S-01C
6002VV
5 600
General
13 400
5 800
120
3.5
WBK17S-01
6203ZZ
9 550
WBK20-01
General
17 900
8 240
155
6.2
WBK20S-01
6204ZZ
12 800
6005ZZ
10 100
WBK20-11
General
17 900
8 240
155
6.2
WBK20S-01
6204ZZ
12 800
WBK25-01
General
20 200
10 000
192
7.2
WBK25S-01
6205ZZ
14 000
WBK25-11
General
20 200
10 000
192
7.2
WBK25S-01
6205ZZ
14 000
WBK04R-11
General
615
490
6.5
0.59
—
—
—
WBK06R-11
General
1 280
930
9
0.59
—
—
—
General
WBK25SF-01
*1: Exclusive for FSS type. *2: Exclusive for VFA type.
*1
Support unit
WBK08S-01
Use
Units: mm
—
B386
9/19/12 3:31:15 PM
Accessories
Support Unit (Support Units for Light Load and Small Equipment)
Support kits for ball screws for transfer equipment
Simple support side support units for VFA type ball screws
Support kits are for RMA type ball screw. In case of RMA1002 or larger rolled ball screws, please use support units for general use.
H 36
PC D
2-j9 drill thru j14 c’bore, 11 deep
0 –0.05
35
43
jd
jC
jD 1
0 –0.05
Brass pad
jd
jD 2
Set screw
25
G
2-j3.4
W M 10
cU
F
E
10
52
20
A
70
A
Reference No.
A
C
d
D1
D2
E
F
G
H
W
U
M
Mass (kg)
WBK04R-11
14
25
4
13
12.5
9
5
5
2.5
19
10
M4×0.5
WBK06R-11
19
30
6
18
17
11
5
6.8
2.5
24
12
M6×0.75 0.23
Reference no. WBK12SF-01*
d 12
WBK15SF-01*
15
Mass (kg)
0.3 0.3
Applicable ball screw VFA1210 VFA1510 VFA1520
0.13
Notes: 1. Use datum surface A for mounting to machine base. 2. This type of simple side support unit is made exclusively for NSK VFA ball screws. This unit simply supports outer diameter of screw shaft. 3. See page B386 for the reference numbers of bearings and radial direction basic dynamic load ratings.
Support unit
Units: mm
Units: mm
Spacer
WBK06R-11
RMA0601 RMA0801 RMA0801.5 RMA0802
Locknut tightening torque (reference) [N·cm] 100 190
Set screw tightening torque (reference) [N·cm] 38 (M2.5) 69 (M3)
Notes: 1. Oscillate bearings slowly so that they fall into place in which run-out of mounting surface is minimal, and then tighten locknut. 2. Support kit is on provisional shaft (bolt) during shipping. 3. When securing support unit on shaft, insert brass pad that is provided with support unit into lock nut hole, and then tighten set screw.
B387
B387-398.indd 387-388
Units: mm
Reference No.
jd
WBK04R-11
Applicable ball screw
jD h9
Reference No.
When using a fixed support unit, it may require an optional spacer to have an effective shoulder surface at where the ball thread is threaded to the end of the shoulder. This is common for the R series for transporting ball screws.
WBK06K WBK08K WBK10K WBK12K WBK15K WBK17K WBK20K WBK25K
Internal Outside Width diameter, d diameter, D B 6 9.5 5.0 8 11.5 5.5 10 14.5 5.5 12 15.0 5.6 15 19.5 10.0 17 24.4 7.0 20 25.5 11.0 25 32.0 14.0
Mass (g) 2 2 4 3 10 13 17 34
Applicable support unit WBK06- * * WBK08- * * WBK10- * * WBK12- * * WBK15- * * WBK17- * * WBK20- * * WBK25- * *
B
B388
9/19/12 3:32:03 PM
Accessories
Support Unit (Support Units for Light Load and Small Equipment)
Screw shaft end configuration
C2
R0.2 or less *, or provide recess
Fixed support side
nL+0.1 0
h9 applicable zone L1
R0.2 or less, or provide recess
n +0.14 0
C1 mL 1
jd 3h7
m1
0 jdn –0.21
jd 2h9
with a ball screw for transporting equipment, add the width of the spacer (B from the table of spacer dimensions on page B388) to L1 dimension below.
jd 1g6
Dimensions of the shaft end configurations for light load and small equipment support units are shown in the table below. When using a spacer
L2
N
Simple support side Support unit
Radius marked with * above is 0.15 or less for WBK04R-11 and WBK06R-11.
Units: mm
Reference No. WBK06- * * WBK08- * * WBK10- * * WBK12- * * WBK15- * * WBK17- * * WBK20- * * WBK25- * * WBK04R-11 WBK06R-11
B389
B387-398.indd 389-390
Bearing journal L1 d1 6 22.5 8 27 10 30 12 30 15 40 17 46 20 53 25 62 4 15 6 17
Fixed support side Locknut thread m1 mL1 M6×0.75 7 M8×1 9 M10×1 10 M12×1 10 M15×1 15 M17×1 17 M20×1 16 M25×1.5 20 M4×0.5 7.5 M6×0.75 7.5
Sealing part d2 N 9.5 3.5 11.5 4 14 6 15 6 19.5 5 24 7 25 10 32 14 — — — —
Chamfer C1 0.2 0.2 0.2 0.2 0.3 0.3 0.3 0.5 0.3 0.3
Units: mm
Reference No. —————— WBK08S- * * WBK10S- * * WBK12S- * * WBK15S- * * WBK17S- * * WBK20S- * * WBK25S- * *
Bearing journal L2 d3 — — 6 9 8 10 10 22 15 25 17 16 20 19 25 20
Simple support side Snap n — 0.8 0.9 1.15 1.15 1.15 1.35 1.35
ring groove dn — 5.7 7.6 9.6 14.3 16.2 19 23.9
nL — 6.8 7.9 9.15 10.15 13.15 15.35 16.35
Chamfer C2 — 0.2 0.2 0.5 0.5 0.5 0.5 0.5
B390
9/19/12 3:32:04 PM
Accessories
Support Unit (For heavy load/machine tools)
(2) Dimensions of support unit for ball screws for heavy-load/machine tools Support units for heavy-load/machine tools use a thrust angular contact ball bearing (TAC Series) with high rigidity and accuracy. The thrust angular contact ball bearing has very
suitable functions and structure as a ball screw support bearing. There are three bearing combinations as shown below.
1
3
7
2
6
4
5
8
Support unit
DFD combination
DF combination
B
A
Parts list Part name
Part No.
1
DFF combination
B391
B387-398.indd 391-392
Housing
Quantity 1
2
Retaining cover
3
High accuracy thrust angular contact ball bearing
1
4
Dust seal
2
5
Collar
2
6
Preload bolt
7
Shim
8
Lock nut
One set
6 or 8 One set 1
Notes: 1. Surface A and B are the datum surfaces to mount a support unit to machine housing. 2. NSK support units are precisely preloaded and adjusted. Do not disassemble the components 1, 2, 3, 4, 5, 6 and 7. 3. Grease is packed into the bearings. 4. Lock nut 8 is exclusively prepared for ball screws. End surface of nut is in strict control being precisely perpendicular to the V thread. Secure lock nut using set screw. Lock nut is also available as accessory. (See page B395.) See page B399 as well for high-precision thrust angular contact ball bearings (TAC Series).
B392
9/19/12 3:32:05 PM
Accessories
Support Unit (For heavy load / machine tools)
L
L3
45°
45°
30
°
15° 15°
30
° DW
4-P * tap, Q * deep (both sides) PCD W
PC
4-P * tap, Q * deep (both sides)
M
jd
M
jD 3
jD 1
jD 2
jd 1*H8
jd
jD g6
jd 1*H8
4-P * tap, Q (both sid P
PC
DV
PC D
L5 L3 O*
V*
L4
O* L1
6-jX dri c'bore j
L2 L
Lock nut
6-jX drill thru c'bore jY × Z
8-jX drill thru c'bore jY × Z
A
Bearing bore d ≤ 30
Dimensions of bearing seat
A
Bearing bore d ≥ 35
Support unit
Support unit
No. WBK 17DF-31 WBK 20DF-31 WBK 25DF-31 WBK 25DFD-31 WBK 30DF-31 WBK 30DFD-31 WBK 35DF-31 WBK 35DFD-31 WBK 35DFF-31 WBK 40DF-31 WBK 40DFD-31 WBK 40DFF-31
d 17 20
D 70 70
D1 106 106
D2 72 72
25
85
130
90
30
85
130
90
35
95
142
102
40
95
142
102
L 60 60 66 81 66 81 66 81 96 66 81 96
L1 32 32 33 48 33 48 33 48 48 33 48 48
L2 15 15
A 80 80
W 88 88
X 9 9
Y 14 14
Z 8.5 8.5
d 1* 45 45
l* 3 3
V* 58 58
P* M5 M5
Q* 10 10
18
100
110
11
17.5
11
57
4
70
M6
12
18
100
110
11
17.5
11
57
4
70
M6
12
18
106
121
11
17.5
11
69
4
80
M6
12
18
106
121
11
17.5
11
69
4
80
M6
12
Notes: 1. Rigidity Values in the table are theoretical values obtained from the elastic deformation between ball groove and balls. 2. Starting torque Starting torque indicates torque due to the preload of the bearing. It does not include seal torque. 3. The tolerance of the shaft bearing seat We recommend h5 class of the fits tolerance.
B393
B387-398.indd 393-394
load rating Ca (N) 21 900 21 900 28 500 46 500 29 200 47 500 31 000 50 500 50 500 31 500 51 500 51 500
axial load (N) 26 600 26 600 40 500 81 500 43 000 86 000 50 000 100 000 100 000 52 000 104 000 104 000
Preload
Axial rigidity
(N) 2 150 2 150 3 150 4 300 3 350 4 500 3 800 5 200 7 650 3 900 5 300 7 850
(N/μm) 750 750 1 000 1 470 1 030 1 520 1 180 1 710 2 350 1 230 1 810 2 400
Maximum Starting torque (N · cm) 19 19 29 39 30 40 34 45 59 36 47 61
Lock nut M M17×1 M20×1 M25×1.5 M30×1.5 M35×1.5
M40×1.5
Mass
D3 L3 (kg) 37 18 1.9 40 18 1.9 3.1 45 20 3.4 3.0 50 20 3.3 3.4 55 22 4.3 5.0 3.6 60 22 4.2 4.7
Bearing seat for unit d 17 20 25 30 35
40
L4 81 81 89 104 89 104 92 107 122 92 107 122
Support unit
Unit: mm Basic dynamic Permissible
L5 23 23 26 26 30
30
4. Dimensions with * (asterisk) mark *Pilot diameter and tapped screws marked with asterisk are used for seal unit installation for NSK standard hollow shaft ball screws. They also can be used for dust cover and damper installation. 5. Grease is packed into bearing. It is not necessary to apply grease before use. 6. Allowable axial load is 0.7 times of load limit.
B394
9/19/12 3:32:05 PM
Accessories
Lock nut, grease unit, and travel stopper
In addition to the support units, NSK has other components for ball screws as shown below.
(3) Lock nuts
with minimum inclination against ball screw center. NSK lock nuts exclusive for ball screw support bearings help to reduce this inclination.
Ball screw support bearings must be installed
B1
1-S Set screw
B1
2-S Set screw
X
jd 1
0 jD –0.1
jd 2
G
jd 3
jD
F
G
jd
X
X
X F
B
4-jd 4
Brass pad
B1
4-jd 5
Section X-X
Brass pad
B
Section X-X
A Type Shapes and dimensions
S Type Shapes and dimensions
A Type lock nuts
S Type lock nuts
A Type lock nuts
Unit: mm Tightening torque (N · cm) (for reference)
S
Set screw tightening torque (reference) [N · cm]
Mass (g)
G
D
F
B
d
B1
WBK06L-01
M6×0.75
14.5
12
5
10
2.75
M3, with a brass pad
190
69 (M3)
3.8
WBK08L-01
M8×1
17
14
6.5
13
4
M3, with a brass pad
230
69 (M3)
6.4
WBK10L-01
M10×1
20
17
8
16
5
M4, with a brass pad
280
147 (M4)
11.2
WBK12L-01
M12×1
22
19
8
17
5
M4, with a brass pad
630
147 (M4)
12.8
WBK15L-01
M15×1
25
22
10
21
6
M4, with a brass pad
790
147 (M4)
20.0
WBK17L-01
M17×1
29
24
13
24
8
M4, with a brass pad
910
147 (M4)
33.1
WBK20L-01
M20×1
35
30
13
26
8
M4, with a brass pad
1670
147 (M4)
50.0
WBK25L-01
M25×1.5
42
36
16
34
10
M6, with a brass pad
2060
490 (M6)
87.0
Accessories
Lock nut reference No.
Note: Insert brass pad and then tighten securing set screw.
S Type lock nuts
Unit: mm
Lock nut reference No.
G
0 D -0.1
B
d1
d2
d3
d4
d5
B1
S
Tightening torque (N · cm) (for reference)
Set screw tightening torque (reference) [N · cm]
Mass (g)
WBK17L-31
M17×1
37
18
30
18
27
4.3
4
10
M6
4 100
490 (M6)
108.4 119.0
WBK20L-31
M20×1
40
18
30
21
30
4.3
4
10
M6
4 500
490 (M6)
WBK25L-31
M25×1.5
45
20
40
26
35
4.3
4
11
M6
8 500
490 (M6)
125.2
WBK30L-31
M30×1.5
50
20
40
31
40
4.3
5
11
M6
10 100
490 (M6)
182.0
WBK35L-31
M35×1.5
55
22
50
36
45
4.3
5
12
M6
13 800
490 (M6)
235.0
WBK40L-31
M40×1.5
60
22
50
41
50
4.3
5
12
M6
15 500
490 (M6)
255.6
B395
B387-398.indd 395-396
B396
9/19/12 3:32:06 PM
Accessories
Lock nut, grease unit, and travel stopper (5) Travel stopper (made-to-order) to a hand grease pump quickly. For details of grease types, see page D13 and for a hand grease pump and nozzles, see page D19.
A travel stopper is installed in some cases to prevent the ball nut from overrunning to the end of ball thread due to a malfunction of the safety system of the equipment or by a human error. NSK has several series of shock-absorbing travel stoppers. The travel stopper is not sold as a single item since it is not for general use.
jD
NSK has numerous grease types that are exclusive for ball screw lubrication. They come in bellows-shaped tubes, which can be attached
Also, a travel stopper cannot be used for ball screw with the end cap type ball recirculation system, because the stopper would come directly into contact with the component for ball recirculation. Please request NSK for the installation of the travel stoppers when ordering a ball screw.
jd
(4) Grease unit
Accessories
NSK greases
O
L Lubricant greases Name
Use
Base oil viscosity 2 mm /s (40°C)
NSK Grease AS2
For heavy load
130
Unit: mm
Applicable Stopper No. Outer dia. Length shaft dia. d D L
Shaft end width (Min.) l
NSK Grease PS2
High-speed, light load
15
NSK Grease LR3
High-speed, medium load
30
NSK Grease LG2
Clean environment
30
BSR 20
20
32
16
5
NSK Grease LGU
Clean environment
100
BSR 25
25
38
16
5
BSR 32
32
46
20
6
BSR 40
40
60
22
6
BSR 50
50
72
24
7
BSR 63
63
85
25
7
Note: This stopper is patented by NSK Ltd.
Shock-absorbing travel stopper B397
B387-398.indd 397-398
B398
9/19/12 3:32:07 PM
Accessories
Thrust angular contact ball bearings for ball screw
Thrust Angular Contact Ball Bearings for Ball Screw
Table 2 Comparison with other types of bearings
B399
B399-406.indd 399-400
Axial deformation (μm)
20
15
Bearing type
)
le ing
) (s 72 ing r ) ea 72 ex) 40 rt b pl ( po 0 (du p B 4 72 su ( ring C ew A 10 ea T scr C rt b 0 l F l 4 a o B BD pp 72 w su C e TA scr 0 l 4 al B 78) earing 0 oller b 4 3 ( al r P9 lindric M y T 40 rust c Th
10
5
0 0
5 000 10 000 Axial load (N)
15 000
Fig. 1 Axial rigidity of various bearings
Bearing rigidity Starting torque (See Fig. 1)
Preload adjustment
Installation structure
Thrust angular contact ball bearing for NSK precision ball screw support unit
High
Low
Not required
Simple
Combined angular contact ball bearing
Low
Low
Not required
Simple
Combination of tapered roller bearings
Low
High
Complicated
Simple
Thrust ball bearing and radial bearing
High
Low
Complicated
Complicated
Thrust cylindrical roller bearing and radial bearing
Extremely high
Extremely high
Complicated
Complicated
Note: Consult NSK when you use these bearings other than the purpose of ball screw support.
(2) Composition of reference number
3 0 TA C 6 2 B D F C 1 0 P N 7 A Bearing bore (mm)
Accuracy code
Bearing model code
Axial play code
Bearing outside diameter (mm)
Accessories
This is highly rigid and accurate ball screw support bearing often used for the machine tools driving mechanism. (a) High axial rigidity High-rigidity achieved by higher contact angle at 60 degrees and an increased number of smaller-diameter balls. (b) Small friction torque Friction torque is far less than that of tapered or cylindrical roller bearing. This contributes to accurate rotation by a smaller driving power. (c) Pre-adjusted axial play Combination bearings are already adjusted to a suitable preload. Universal combination bearing (SU) furnishes certain preload for all combinations (DB, DF, and other). (d) Simple mounting structure A duplex combination of bearings can receive axial and radial loads. Therefore, the installation structure is simpler than when both a thrust bearing and a radial bearing are used. (e) Easy handling Inner and outer rings are inseparable, and are easy to handle. (f) Superb polyamide resin retainer Uses polyamide resin retainer which is superb to friction and furnishes high precision rotations.
720 Angu8B ( 4 lar c 0 onta ct ba80) HR3 ll bea Tap 2208J ring ered ( rolle 40 r be arin80) g 51 Th 10 ru 8 st ( ba 40 ll b ea 6 rin 0) g
(1) Features
Combination code
Internal design code
Note: As "30 TAC 62 B," any part of the first half of the reference number is referred to as "nominal size" in this catalog.
B400
9/19/12 3:33:02 PM
Accessories
Thrust angular contact ball bearings for ball screw
(3) Combinations of bearings Generally, a set uses more than two pieces (referred to as 'two rows') of bearings and, thus the preload is applied. There are two types of combination: A Combined bearings Bearings are adjusted as a single combined set. Since the bearing alignment is pre-set, there is no interchangeability between the bearing set. A Universal combination bearing (SU) Single bearings are manufactured under strict control of component accuracy so that they can be universally assembled as a combination of ball screw support bearing set.
(a) Combined bearings • Fig. 2 shows examples of combinations. There is "V" mark on the outside surface of the bearing to avoid misarrangement. A complete letter "V" should be formed when all bearings align correctly to form a set. • DF combination which easily absorbs misalignment with the ball screw nut is used in general.
(b) Universal combination bearing (SU) • Unlike the above case, the marks on the outside surface of bearings do not form a letter "V." The tip of the "V" on each bearing simply indicates the direction to which axial load can be applied.
DB
DFD Accessories
DF
DF
DFD
Fig. 3 Example of universal combination (SU) and "V" mark
Fig. 2 Examples of combination and "V" mark
B401
B399-406.indd 401-402
B402
9/19/12 3:33:03 PM
Accessories
Thrust angular contact ball bearings for ball screw
(4) Preload, rigidity, and starting torque
(5) Accuracy
The Table 3 shows preload, rigidity (spring modulus), and starting torque with grease lubrication. (The starting torque should be 1.4 times higher when oil is used as a lubricant.) Consult NSK for the bearing combinations not included in the table below.
(a) Accuracy grades Uses NSK standard PN7A and PN7B which are equivalent to JIS4 grade of the radial ball bearing. Combined bearing ––––––––––––––– PN7A Universal combination bearing ––– PN7B However, PN7A is stricter than JIS4 grade regarding axial run out of inner and outer rings. PN7B is stricter regarding the tolerance of the bore and outside diameter (Table 4).
(b) Fits Table 5 shows recommended values of the tolerance of shaft and housing bore.
Table 3 Preload, rigidity, and starting torque Reference No. 15TAC 47B
Quadruplet combination DFF
Triplex combination DFD
Duplex combination DF Axial play code
Preload (N)
Rigidity (N/µm)
Starting torque (N · m)
C10
2 150
750
17TAC 47B
C10
2 150
20TAC 47B
C10
2 150
25TAC 62B
C10
30TAC 62B
C10
35TAC 72B 40TAC 72B
Rigidity (N/µm)
Starting torque (N · m)
0.20
C10
4 300
1 470
0.29
1 080
0.20
C10
4 300
1 470
0.29
1 080
0.20
C10
4 300
1 470
0.29
4 300
1 470
0.31
C10
6 250
1 960
0.46
4 500
1 520
0.33
C10
6 650
2 010
0.49
C10
5 200
1 710
0.37
C10
7 650
2 350
0.55
C10
5 300
1 810
0.38
C10
7 850
2 400
0.57
0.48
C10
6 750
1 960
0.65
C10
10 300
2 650
0.96
0.29
C10
5 600
1 910
0.40
C10
8 250
2 550
0.59
Axial play code
Rigidity (N/µm)
Starting torque (N · m)
0.14
C10
2 950
1 080
750
0.14
C10
2 950
750
0.14
C10
2 950
3 150
1 000
0.23
C10
3 350
1 030
0.24
C10
C10
3 800
1 180
0.28
C10
3 900
1 230
0.28
40TAC 90B
C10
5 000
1 320
45TAC 75B
C10
4 100
1 270
45TAC 100B
C10
5 900
1 520
0.58
C10
8 050
2 210
0.78
C10
11 800
3 000
1.16
50TAC 100B
C10
6 100
1 570
0.60
C10
8 250
2 300
0.80
C10
12 300
3 100
1.18
55TAC 100B
C10
6 100
1 570
0.60
C10
8 250
2 300
0.80
C10
12 300
3 100
1.18
55TAC 120B
C10
6 650
1 810
0.64
C10
9 100
2 650
0.86
C10
13 200
3 550
1.27
60TAC 120B
C10
6 650
1 810
0.64
C10
9 100
2 650
0.86
C10
13 200
3 550
1.27
Table 4 Tolerance: thrust angular contact ball bearing for ball screw support Unit: µ m Tolerance of bore
Nominal size of bearing bore or outside diameter (mm)
Tolerance of outside diameter
Accuracy grade PN7A
Accuracy grade
PN7B
PN7A
PN7B
over
or less
upper
lower
upper
lower
upper
lower
upper
lower
10 18 30 50 80
18 30 50 80 120
0 0 0 0 0
–4 –5 –6 –7 –8
0 0 0 0 0
–4 –4 –4 –5 –6
– – 0 0 0
– – –6 –7 –8
– – 0 0 0
– – –4 –5 –6
Tolerance of inner ring width Accuracy grade PN7A PN7B upper lower 0 0 0 0 0
–80 –120 –120 –150 –200
Axial run out of inner or outer ring Accuracy grade PN7A PN7B Maximum 2.5 2.5 2.5 2.5 2.5
Accessories
Axial play code
Preload (N)
Preload (N)
Table 5 Tolerance of shaft bearing seat and housing bore Unit: µ m Size of shaft or housing bore (mm)
Tolerance of shaft bearing seat h5
Tolerance of housing hole H6
over
or less
upper
lower
upper
lower
10 18 30 50 80
18 30 50 80 120
0 0 0 0 0
–8 –9 –11 –13 –15
– – +16 +19 +22
– – 0 0 0
Note: The tolerance of the outer ring width is the same as that of the inner ring width of the same bearing.
B403
B399-406.indd 403-404
B404
9/19/12 3:33:03 PM
Accessories
Thrust angular contact ball bearings for ball screw
**TAC**B Nominal contact angle 60 degrees
B r
r1
Com
ber o
r
f the
bina
row
tion
that
jD 2
jd 2
receiv
Duplex
cod
DF
e
es ax
ial lo
ad
Dimensions (mm)
DFD
Quadruplet DTD
DFT DFF
DFT
1.9
–
1.43 2.33
–
1.17 2.33 2.53
Y 0.54
–
0.77 0.35
–
0.89 0.35 0.26
X 0.92 0.92 0.92 0.92 0.92 0.92 0.92 0.92 Fa /Fr > e Y
External dimensions (mm)
Triplex
DT
One row Two rows One row Two rows Three rows One row Two rows Three rows
X
Fa /Fr ≤ e
jd
jd 1
jD 1
Num
e = 2.17
r jD
Dynamic equivalent load Pa = XFr + Fa Bearing configuration
Permissible rotational speed (min-1)
1
1
1
1
1
1
1
One row sustains load DF (N)
Permissible axial load Two rows sustain load DT, DFD, DFF (N)
Three rows sustain load DTD, DFT (N)
Mass (kg)
(Reference)
d
D
B
r Min.
r1 Min.
d1
d2
15 17 20 25
47 47 47 62
15 15 15 15
1 1 1 1
0.6 0.6 0.6 0.6
27.2 27.2 27.2 37
34 34 34 45
34 34 34 45
39.6 39.6 39.6 50.7
6 000 6 000 6 000 4 500
8 000 8 000 8 000 6 000
15TAC 47B 17TAC 47B 20TAC 47B 25TAC 62B
21 900 21 900 21 900 28 500
35 500 35 500 35 500 46 500
47 500 47 500 47 500 61 500
26 600 26 600 26 600 40 500
53 000 53 000 53 000 81 500
79 500 79 500 79 500 122 000
0.144 0.144 0.135 0.252
30 35 40 40
62 72 72 90
15 15 15 20
1 1 1 1
0.6 0.6 0.6 0.6
39.5 47 49 57
47 55 57 68
47 55 57 68
53.2 60.7 62.7 77.2
4 300 3 600 3 600 3 000
5 600 5 000 4 800 4 000
30TAC 62B 35TAC 72B 40TAC 72B 40TAC 90B
29 200 31 000 31 500 59 000
47 500 50 500 51 500 95 500
63 000 67 000 68 500 127 000
43 000 50 000 52 000 89 500
86 000 100 000 104 000 179 000
129 000 150 000 157 000 269 000
0.224 0.310 0.275 0.674
45 45 50
75 100 100
15 20 20
1 1 1
0.6 0.6 0.6
54 64 67.5
62 75 79
62 75 79
67.7 84.2 87.7
3 200 2 600 2 600
4 300 3 600 3 400
45TAC 75B 45TAC 100B 50TAC 100B
33 000 61 500 63 000
53 500 100 000 102 000
71 000 133 000 136 000
57 000 99 000 104 000
114 000 198 000 208 000
170 000 298 000 310 000
0.270 0.842 0.778
55 55 60
100 120 120
20 20 20
1 1 1
0.6 0.6 0.6
67.5 82 82
79 93 93
79 93 93
87.7 102.2 102.2
2 600 2 200 2 200
3 400 3 000 3 000
55TAC 100B 55TAC 120B 60TAC 120B
63 000 67 500 67 500
102 000 109 000 109 000
136 000 145 000 145 000
104 000 123 000 123 000
208 000 246 000 246 000
310 000 370 000 370 000
0.714 1.23 1.16
D1
Notes: 1. Values are based on a standard preload (C10).
B405
B399-406.indd 405-406
D2
Grease lubrication Oil lubrication
Bearing No.
Accessories
Basic dynamic load rating Ca One row Two rows Three rows sustaining load sustaining load sustaining load DF DT, DFD, DFF DTD, DFT (N) (N) (N)
1
2. "Row" means the quantity of bearings that receive axial load. "Two rows" means two bearings are receiving axial load.
B406
9/19/12 3:33:04 PM
