Series 647 Hydraulic Wedge Grips Product Information Axial Grips Axial-Torsional Grips All Temperature Grips
100-027-131 E
Copyright information
© 2000-2003 MTS Systems Corporation. All rights reserved.
Trademark information
MTS is a registered trademark of MTS Systems Corporation. DTE and SHC are registered trademarks of Mobil Corporation. Molykote is a registered trademark of Dow Chemical Corporation. LPS is a registered trademark of LP Systems Corporation.
Contact information
Publication information
MTS Systems Corporation 14000 Technology Drive Eden Prairie, Minnesota 55344-2290 USA Toll Free Phone: 800-328-2255 (within the U.S. or Canada) Phone: 952-937-4000 (outside the U.S. or Canada) Fax: 952-937-4515 E-mail:
[email protected] http://www.mts.com ISO 9001 Certified 0 $ 18$ / 3 $ 57 1 80%(5
3 8%/,&$ 7,21 ' $ 7(
100-027-131 A
February 2000
100-027-131 B
December 2000
100-027-131 C
June 2001
100-027-131 D
October 2001
100-027-131 E
February 2003
Contents Introduction 5 Component Identification Functional Description Specifications
7 10
13
Force and Torque Capacities Grip Dimensions
14
18
Model 647.02B Wedges
20
Model 647.10 Wedges
23
Model 647.25 Wedges
26
Model 647.50 Wedges
29
Model 647.100 Wedges
30
Installation 31 Installing Axial Grips
32
Installing Axial-Torsional Grips
36
Installing the Grips in an Environmental Chamber Environmental Chambers with U-Plugs
Environmental Chambers Without U-Plugs Installing Extension Rods
46
56
Aligning the Wedge Openings
62
Preloading the Spiral Washers
63
Series 647 Hydraulic Wedge Grips
41
42
Contents
3
Operation 65 Determining the Gripping Pressure Changing Wedges
66
70
Changing Standard Wedges Changing Wide Wedges Installing a Specimen Removing a Specimen
71
72
74 77
Maintenance 79 Service 81 Axial and Axial-Torsional Seal Replacement All Temperature Seal Replacement
4
Contents
83
86
Series 647 Hydraulic Wedge Grips
Introduction The Series 647 Hydraulic Wedge Grips grasp and hold a specimen in place during testing, and provide a constant, hydraulically actuated gripping force regardless of the applied test loads. The grips are specifically designed for static or fatigue testing applications in MTS testing systems. A variety of wedges allow the grips to be used to test a variety of materials. Optional equipment includes a cooling/warming kit and an external hydraulic grip supply.
Contents
Component Identification Functional Description Specifications
7
10
13
The size and shape of the Series 647 Hydraulic Wedge Grips vary among the models.
Series 647 Hydraulic Wedge Grips
Series 647 Hydraulic Wedge Grips
Introduction
5
What you need to know
Related products
MTS Systems Corporation assumes that you know how to use your controller. See the appropriate manual for information about performing any controller-related step in this manual’s procedures. You are expected to know how to perform the following procedures: •
Turning hydraulic pressure on and off
•
Selecting a control mode
•
Manually adjusting the actuator position
•
Monitoring a sensor signal
•
Zeroing a sensor output
See the following product information manuals for information about the related products. •
•
6
Introduction
The hydraulic controls for the Series 647 Hydraulic Grips can be located on the front panel of the load unit or on an external unit (controls and a hydraulic power unit for the grips). –
If hydraulic grip controls are located on the load unit, see your load unit product information manual.
–
If hydraulic grip controls are added to your load unit, see the 685.53 Hydraulic Grip Kit Product Information manual (part number 015-029-701).
–
If you have a dedicated hydraulic supply for the grips, see the Series 685 Hydraulic Grip Supply Product Information manual (part number 015-205-001).
If you are using an environmental chamber, see the Series 651 Environmental Chambers Product Information manual (part number 015-205-001).
Series 647 Hydraulic Wedge Grips
Component Identification Load Unit Crosshead Force Transducer
Shim Spiral Washer Set
Upper Grip
Connector Stud 647 Hydraulic Wedge Grip
Hydraulic Pressure and Return Lines
Wedges
Water Cooling Lines
Specimen Guide 647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
Wedges
Upper Grip Assembly
Lower Grip Actuator Rod Load Unit Base Plate
Axial Grips
Environmental Chamber
Adapter Plate Left Hand Thread
Upper Coupling
Lower Grip Assembly
Right Hand Thread 647 Hydraulic Wedge Grip 647 Hydraulic Wedge Grip
Water Cooling Lines
All Temperature Grips
647 Hydraulic Wedge Grip
Left Hand Thread
Lower Coupling
Right Hand Thread
Axial/Torsional Grips Series 647 Hydraulic Grip Components
Series 647 Hydraulic Wedge Grips
Introduction
7
Hydraulic Grip Components Item Load unit Crosshead and Base Plate
Description Provides the structure to mount the grips and other components in the force train. It is also the reaction mass for the force train. The grips are mounted to the force transducer and actuator rod in the load unit. • Some load units have the actuator mounted in the base plate and the force transducer mounted to the crosshead. • Some load units have the force transducer mounted in the base plate and the actuator mounted to the crosshead.
Force Transducer
Measures the axial forces applied to the specimen. An axial-torsional version also measures the rotational forces applied to the specimen.
Upper and lower grips
Clamps a specimen in place. The grips house the wedges and the hydraulic components that operate the grips. The grip assemblies of the all temperature grips have the components separated so those components most affected by extreme temperatures are located outside the extreme environment.
Hydraulic pressure and return lines
Ports the hydraulic fluid to and from the grips. The hydraulic fluid comes from a system hydraulic power unit (HPU) or a dedicated hydraulic grip supply. Each grip has two hydraulic lines connected to it; a hydraulic pressure port and a hydraulic return port.
Wedges
Contacts and holds the specimen in place. A variety of wedges are available, for flat specimens, round specimens, hard specimens, and soft specimens. Wedges are available as matched sets of four. Each model has wedges that are designed for its use. See “Specifications” on page 13 for a listing of the wedge part numbers for each grip model.
Specimen guide
Helps align the specimen when it is installed. The specimen guide can only be used with flat specimens.
Actuator rod
Applies axial or axial and torsional forces to specimens. The actuator is a hydraulically powered device that provides linear displacement of (or forces into) a specimen. For axial-torsional systems, the actuator applies both axial and torsional forces to the specimen The end of the actuator rod is threaded so a grip can be mounted to it. The actuator rod can be located in the base or the crosshead of the load unit.
Water cooling lines
Provides the source of water for heating or cooling. The water is circulated through the grips to keep them warm or cool when operating in a cold or hot environmental chamber.
Environmental chamber
Allows a specimen to be tested at different temperatures (hot or cold). Environmental chambers are insulated boxes that surround the specimen and grips.
8
Introduction
Series 647 Hydraulic Wedge Grips
Hydraulic Grip Components Item Axial attachment kit
Description Includes the required components to install the grips. The attachment kit contains shim washers, spiral washers, and connector studs. Each grip model/load unit model combination has a unique attachment kit.
Shims
Allows the upper and lower grips to be aligned. When the grips are installed, the upper and lower grips might not be aligned. Shims can be added so the grips are aligned when they are tightened on the connector stud. The shims are available in thicknesses that correspond with 1/8 to 1/2 turns.
Spiral washers
Ensures preloading without inducing offsets in the force train. They provide a backlash-free union of threaded components. They preload the connecting stud to a minimum axial load that is 110% of the test maximum. See “Spiral washers” on page 11 for more information.
Connector stud
Mounts the grips to the other components in the force train. Connector studs are threaded rods that connect the grips with an actuator rod or force transducer.
Axial-torsional attachment kit
Includes the required components to install the grips. The attachment kit contains an adapter plate, an upper coupling, and a lower coupling. Each grip model/load unit model combination has a unique attachment kit.
Adapter plate
Allows axial-torsional grips to be mounted to a force transducer. The adapter provides the thread needed to use the couplings.
Upper and lower couplings
Clamps the grips to the to the actuator and force transducer (via an adapter). The couplings have left and right handed threads that preloads the grip connection and prevents offsets in the force train. See “Couplings” on page 11 for more information.
Series 647 Hydraulic Wedge Grips
Introduction
9
Functional Description The Series 647 Hydraulic Wedge Grips are typically mounted in an MTS load unit to secure the specimen under test. Hydraulic pressure to the grips is supplied by and adjusted at an external hydraulic grip supply. The grips have a side-loading design for quick and easy specimen installation. Wedge Chamber
Specimen Guide (flat specimens only)
Specimen Guide (flat specimens only)
Wedges
Wedge Chamber
Hydraulic Release
Hydraulic Pressure Preload Chamber
Grip Piston Anti-Rotate Adapter (Axial-Torsional Only)
End Cap
Piston Extension Hydraulic Release
Cylinder
Grip Piston Preload Chamber Anti-Rotate Blocks (Axial-Torsional Only)
Gripping specimens
End Cap
Hydraulic Pressure
The grips provide a constant, hydraulically actuated gripping force regardless of the applied test loads. The specimen gripping force is adjustable to prevent specimen damage by the grips or specimen slippage during the test. Each grip (upper and lower) is independently actuated. When actuated, the preload chamber locks all moving grip parts in position, thus eliminating backlash when cycling between tension and compression, thus the specimen can be cycled from full tension through zero to full compression with no backlash. Once a specimen is positioned between the grip wedges, hydraulic pressure is applied to the preload chamber. This pressure pulls the wedge chamber toward the piston, forcing the wedges to clamp the specimen. The pressure applied to the preload chamber can be adjusted to a level which clamps the specimen securely but does not damage the specimen by applying excessive gripping force.
10
Introduction
Series 647 Hydraulic Wedge Grips
Wedges
Each grip model has its own selection of wedges. Not all wedge options are available for all grip models. Three types of wedges are available for use with the grips: flat wedges, round wedges, and vee-notched wedges. •
Flat wedges grip flat specimens. Both narrow and wide wedges are available.
•
Round wedges can only grip a round specimen of a specific diameter.
•
Vee-notched wedges can grip a range of round specimens.
Flat wedge surfaces can be finished with diamond serrations, with a Surfalloy® coating, or a smooth finish. •
Diamond serrated surfaces can grip materials such as soft steels and plastics.
•
Surfalloy surfaces can grip hard or brittle materials. Surfalloy incorporates a grit onto the wedge surface.
•
Smooth surfaces can grip specimens that cannot tolerate imperfections on the grip surface. This surface also has a lower force rating.
Water-cooled wedges are available for applications where the specimen is heated. A water cooling kit includes the parts to connect the wedges to a water source and regulate the water flow.
Spiral washers
The optional Model 601 Spiral Washers are commonly used when installing axial grips. They provide fatigue-resistant connections between elements of the force train and to minimize the effects of backlash. The spiral washers are placed over the connector studs at each connection and adjusted to place a constant preload on the stud. The spiral washers also minimize the possibility of backlash due to loose-fitting or worn stud threads. When cyclic loads below the tensile force level of the preload are applied to the connections, the load is distributed between the surfaces of the spiral washers and the stud in a ratio of the relative stiffness of the parts. The spiral washers have a large surface area and therefore greater stiffness. They react to most of the load and keep the stress in the stud below its fatigue runout level.
Couplings
Special upper and lower couplings clamp the grips to the actuator and force transducer for axial-torsional grips. Each coupling has two different thread patterns—a right-hand thread with a 3 mm pitch, and a left-hand thread with a 2 mm pitch. Half of the coupling matches the thread of the grip, and the other half matches the thread of the actuator or force transducer adapter. A label on each coupling indicates the direction to tighten, torque rotation, and torque requirements. Here is an example.
1
Lower Coupling Axial Rating Torsion Rating 1. Insert bolts, finger tight. 2. Turn coupling
3
to tighten joint 3. Torque bolts 11 ft-lbs / 14.9 N-m.
25 kN 220 N-m
4
Grip/Fixture Force Xdcr
2
MTS Systems Corporation Mpls., MN. Patent Pending PN 466350-01
Series 647 Hydraulic Wedge Grips
Introduction
11
All temperature
The grip mechanism (the wedge chamber and wedges) is fully enclosed in the environmental chamber to secure the specimen under test. The grip actuating mechanism (the end cap, preload chamber and piston) is outside the environmental chamber eliminating the need for high-temperature hydraulic fluid and allowing a broader temperature range for testing — from -129° to +315°C (-200° to +600°F) or -129° to +540°C (-200° to +1000°F) depending on the grip model. With the grip mechanism inside the environmental chamber, the thermal stresses caused by temperature gradients along the length of the specimen are minimized. The grip actuating mechanism is water cooled/warmed to further protect it from temperature extremes.
Environmental chambers
The grips can be mounted for room temperature testing or testing in an environmental chamber. The temperature range of the grips is determined by the type of seals used in the grips and the type of fluid used for the grips. There are two methods for using grips in an environmental chamber (as shown in the following figure).
Using Extension Rods with Axial Grips
Using All Temperature Grips
647 Hydraulic Wedge Grip
l
647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
12
Introduction
Series 647 Hydraulic Wedge Grips
Specifications Contents
Force and Torque Capacities Grip Dimensions
18
Model 647.02B Wedges
20
Model 647.10 Wedges
23
Model 647.25 Wedges
26
Model 647.50 Wedges
29
Model 647.100 Wedges
Temperature ranges
14
30
The temperature range of the grips is determined by the type of seals used in the grips and the type of hydraulic fluid used with the grips. The grips are available in the following temperature ranges: •
-40°C to 177°C (-40°F to 350°F)
•
-130°C/315°C (-200°F/600°F)
•
-130°C/540°C (-200°F/1000°F)
Not all grip models are available in all temperature ranges.
Grip weights
Weight Model
Axial*
Axial-Torsional*
All Temperature†
647.02B
5 kg (10 lb)
7 kg (15 lb)
15/17 kg (31/38 lbs)‡
647.10
30 kg (67 lb)
29 kg (65 lb)
57/65 kg (125/142 lbs)
647.25
77 kg (170 lb)
95 kg (210 lb)
131/141 kg (269/289 lbs)
647.50
148 kg (325 lb)
-
-
647.100
386 kg (850 lb)
-
-
* Per Grip † Upper/Lower Grip ‡ Model 647.02A
Series 647 Hydraulic Wedge Grips
Introduction
13
Force and Torque Capacities The amount of torque the grips can produce is reduced with biaxial operation. The amount of torque is affected by the amount of axial force and the diameter of the specimen. The graphs, which follow the table, illustrate the axial-torsional performance envelope of the Model 647.02B and Model 647.10 Hydraulic Wedge Grips and the Model 647.25 AxialTorsional Wedge Grips.1 Model
Static Force
Dynamic Force
Grip Pressure
647.02B*
31 kN (7 kip)
25 kN (5.5 kip)
21 MPa (3,000 psi)
647.10†
120 kN (27 kip)
100 kN (22 kip)
21 MPa (3,000 psi)
647.25‡
333 kN (75 kip)
250 kN (55 kip)
69 MPa (10,000 psi)
647.50
550 kN (120 kip)
500 kN (110 kip)
69 MPa (10,000 psi)
647.100
1200 kN (264 kip)
1000 kN (220 kip)
69 MPa (10,000 psi)
* Torsional force for the axial-torsional version is 220 N·m (2,000 in·lb). † Torsional force for the axial-torsional version can be 550 N·m (5,000 in·lb) or 1100 N·m (10,000 in·lb) ‡ Torsional force for the axial-torsional version is 2200 N·m (20,000 in·lb)
1 Charts assume that edges for RND specimens are diamond face vee or RND wedges.
14
Introduction
Series 647 Hydraulic Wedge Grips
Model 647.02B Maximum Torque vs. Axial Load
Series 647 Hydraulic Wedge Grips
Introduction
15
Model 647.10 Maximum Torque vs. Axial Load
16
Introduction
Series 647 Hydraulic Wedge Grips
Model 647.25 Maximum Torque vs. Axial Load
Series 647 Hydraulic Wedge Grips
Introduction
17
Grip Dimensions
C
A
E
D
l 647 Hydraulic Wedge Grip
Axial Grip Dimensions Model
Height
Diameter
Stud Size
647.02B
135 mm (5.30 in)
114 mm (4.5 in)
M12 x 1.25 (1/2 in - 20)
647.10A
178 mm (7.02 in)
203 mm (8.0 in)
M27 x 2 (1 in - 14)
647.25A
251 mm (9.89 in)
267 mm (10.5 in)
M36 x 2 (1 1/2 in - 12)
647.50A
292 mm (11.5 in)
330 mm (13.0 in)
M52 x 2 (2 in - 12)
647.100A
415 mm (16.32 in)
444.5 mm (17.5 in)
M76 x 2 (3 in - 12)
Axial-Torsional Grip Dimensions Model
Height
Diameter
Stud Size*
647.02A-22
171 mm (6.8 in)
114 mm (4.5 in)
(4) M8 x 1.25
647.10A-05
206 mm (8.1 in)
203 mm (8.0 in)
M68 x 2 (LH)
647.10A-11
235 mm (9.25 in)
203 mm (8.0 in)
M68 x 2 (LH)
647.25
336 mm (13.22 in)
267 mm (10.5 in)
M92 x 3 (LH)
* LH specifies a left handed thread.
18
Introduction
Series 647 Hydraulic Wedge Grips
All Temperature Grip Dimensions Model
A upper/lower
B
C
D upper/lower
E
Stud Size
647.02A
373/490 mm (14.7/19.3 in)
114 mm (4.5 in)
112 mm (4.4 in)
151/266 mm (5.9/10.5 in)
66 mm (2.6 in)
M12 x 1.25 (1/2 in - 20)
647.10A
447/589 mm (17.6/23.2 in)
203 mm (8.0 in)
159 mm (6.25 in)
155/298 mm (6.1/11.7 in)
98 mm (3.9 in)
M27 x 2 (1 in - 14)
647.25A
556/678 mm (21.9/26.7 in)
267 mm (10.5 in)
225 mm (8.9 in)
165/286 mm (6.5/11.3 in)
122 mm (4.8 in)
M36 x 2 (1 1/2 in - 12)
Series 647 Hydraulic Wedge Grips
Introduction
19
Model 647.02B Wedges These wedges fit the Model 647.02B Hydraulic Wedge Grip. The usable width of these wedges is 25 mm (1 in) or 50 mm (2 in) for those listed as “Wide,” the insertion depth is 38 mm (1.5 in). They are sold in matched sets of four. Flat Specimen Wedges (part 1 of 2) Surface
Specimen Thickness*
Part Number† (Wide)
-40°C to 177°C (-40°F to 350°F)
20
90° Diamond
0–7.1 mm (0–0.28 in)
050-507-906‡ (054-585-001)
90° Diamond
7.1–14.4 mm (0.28–0.57 in)
050-507-907 (054-585-002)
90° Diamond
13.4–20.5 mm (0.53–0.81in)
050-507-901
(054-585-003)
90° Diamond
16.9–24 mm (0.66–0.95 in)
050-507-902
(054-585-004)
90° Diamond
18.8–25.9 mm (0.74–1.02in)
050-507-905
Surfalloy
0–7.1 mm (0–0.28 in)
050-507-901§ (054-585-005)
Surfalloy
7.1–14.4 mm (0.28–0.57 in)
050-507-917
(054-585-006)
Surfalloy
13.4–20.5 mm (0.53–0.81in)
050-507-904
(054-585-007)
Surfalloy
16.9–24 mm (0.66–0.95 in)
050-507-903
(054-585-008)
Serrated
0–7.1 mm (0–0.28 in)
050-507-919
(054-585-009)
Serrated
7.1–14.4 mm (0.28–0.57 in)
050-507-920
(054-585-010)
Serrated
13.4–20.5 mm (0.53–0.81in)
050-507-921
(054-585-011)
Serrated
16.9–24 mm (0.66–0.95 in)
050-507-922
(054-585-012)
Serrated
18.8–25.9 mm (0.74–1.02in)
050-507-923
Smooth
0–7.1 mm (0–0.28 in)
050-507-924
(054-585-014)
Smooth
7.1–14.4 mm (0.28–0.57 in)
050-507-925
(054-585-015)
Smooth
13.4–20.5 mm (0.53–0.81in)
050-507-926
(054-585-016)
Smooth
16.9–24 mm (0.66–0.95 in)
050-507-927
(054-585-017)
Smooth
18.8–25.9 mm (0.74–1.02in)
050-507-928
Corrugated
0–7.1 mm (0–0.28 in)
050-507-929
(054-585-018)
Corrugated
7.1–14.4 mm (0.28–0.57 in)
050-507-930
(054-585-019)
Corrugated
13.4–20.5 mm (0.53–0.81in)
050-507-931
(054-585-020)
Corrugated
16.9–24 mm (0.66–0.95 in)
050-507-932
(054-585-021)
Corrugated
18.8–25.9 mm (0.74–1.02in)
050-507933
Introduction
Series 647 Hydraulic Wedge Grips
Flat Specimen Wedges (part 2 of 2) Surface
Specimen Thickness*
Part Number† (Wide)
–129°C to 315°C (-200°F to 600°F) 90° Diamond
0–7.1 mm (0–0.28 in)
041-842-010
90° Diamond
4.1–10.9 mm (0.16–0.43 in)
041-842-011
Surfalloy
0–7.1 mm (0–0.28 in)
041-842-018
Surfalloy
4.1–10.9 mm (0.16–0.43 in)
041-842-019
–129°C to 540°C (-200°F to 1000°F)
* † ‡ §
90° Diamond
0–7.1 mm (0–0.28 in)
041-842-016
90° Diamond
4.1–10.9 mm (0.16–0.43 in)
041-842-017
Surfalloy
0–7.1 mm (0–0.28 in)
041-842-023
Surfalloy
4.1–10.9 mm (0.16–0.43 in)
041-842-036
Tolerance for specimen shank flatness is ±.005 in (.127 mm). The water cooling kit is part number 048-974-801. Water cooled wedges part number 052-818-701. Water cooled wedges part number 052-818-702.
Round Specimen Wedges Surface
Diameter*†
Part Number (water cooled)‡
-40°C to 177°C (-40°F to 350°F) Surfalloy
10 mm
050-507-912
(052-818-703)
Surfalloy
12 mm
050-507-934
Surfalloy
15 mm
050-507-913
Surfalloy
25 mm
050-507-914
Surfalloy
0.5 in
050-507-915
Surfalloy
1 in
050-507-916
Smooth
10 mm
(052-818-706)
Smooth
15 mm
(052-818-707))
Smooth
20 mm
(052-818-709)
Smooth
0.5 in
(052-818-708)
(052-818-704)
(052-818-705)
* The SI units do not have US customary equivalents (and vice versa). † Allowable tolerance for the specimen shank diameter is ±.001 in (±.0254 mm) for metal specimens, ±.005 in (±.127mm) for plastic/low modulus composite specimens, and ±.0005 in (±.0127 mm) for ceramic specimens. ‡ The water cooling kit is part number 048-974-801.
Series 647 Hydraulic Wedge Grips
Introduction
21
The vee wedge specimen diameter specification represents the diameter range if the specimen is installed from the side of the grips (the widest opening). The specimen diameter also lists the maximum specimen diameter if the specimen is installed from the top of the grips. Vee Specimen Wedges Surface
When Side/Top Loading*
Part Number (water cooled)†
-40°C to 177°C (-40°F to 350°F) 90° Diamond
6.3–9.4/11.9 mm (0.25–0.37/0.47 in)
(052-818-710)
Serrated
3.0–8.1/9.4 mm (0.12–0.32/0.37 in)
050-507-908
Serrated
8.9–10.9/15.2 mm (0.35–0.43/0.60 in)
050-507-909
Surfalloy
14.0–18.0/20.8 mm (0.55–0.71/0.82 in)
050-507-910
Surfalloy
20.1–22.9/27.2 mm (0.79–0.90/1.07 in)
050-507-911
–129°C to 315°C (-200°F to 600°F) Serrated
6.3–9.4/11.9 mm (0.25–0.37/0.47 in)
041-842-013
Serrated
10.2–10.2/16.0 mm (0.40–0.40/0.63 in)
041-842-014
–129°C to 540°C (-200°F to 1000°F) Serrated
6.3–9.4/11.9 mm (0.25–0.37/0.47 in)
041-842-021
Serrated
10.2–10.2/16.0 mm (0.40–0.40/0.63 in)
041-842-022
* Side load diameter range/maximum top load diameter. † The water cooling kit is part number 048-974-801.
22
Introduction
Series 647 Hydraulic Wedge Grips
Model 647.10 Wedges These wedges fit the Model 647.10 Hydraulic Grip. The usable width of the standard wedges is 44 mm (1.75 in), or 76.2 mm (3 in) for the wedges listed as “Wide,” the insertion depth is 63.5 mm (2.5 in). They are sold in matched sets of four. Flat Specimen Wedges Surface*
Specimen Thickness†
Part Number (water cooled‡)
-40°C to 177°C (-40°F to 350°F) 90° Diamond
0–7.6 mm (0–0.30 in)
041-842-101
(046-838-702)
90° Diamond
7.1–14.2 mm (0.28–0.56 in)
041-842-102
(046-838-701)
90° Diamond
11.7–19.1 mm (0.46–0.75 in)
041-842-109
(046-838-713)
Wide 90° Diamond
7.1–14.2 mm (0.28–0.56 in)
046-198-603
Wide 90° Diamond
0–7.6 mm (0–0.30 in)
046-198-604
Wide 90 Diamond
11.4–19.1 mm (0.45–0.75 in)
046-1986-10
Wide 90 Diamond
17–25.4 mm (0.67–1.0 in)
046-198-606
Surfalloy
0–7.6 mm (0–0.30 in)
041-842-108
(046-838-705)
Surfalloy
7.1–14.2 mm (0.28–0.56 in)
041-8421-11
(046-838-706)
Surfalloy
11.7–19.1 mm (0.46–0.75 in)
041-842-121
Wide Surfalloy
7.1–14.2 mm (0.28–0.56 in)
046-198-601
Wide Surfalloy
0–7.6 mm (0–0.30 in)
046-198-602
Smooth
0–7.6 mm (0–0.30 in)
041-842-106
Smooth
7.1–14.2 mm (0.3–0.56 in)
041-842-105
90° Diamond
0–7.6 mm (0–0.30 in)
041-842-125
90° Diamond
7.1–14.2 mm (0.28–0.56 in
041-842-126
Surfalloy
0–7.6 mm (0–0.30 in)
041-842-116
Surfalloy
7.1–14.2 mm (0.28–0.56 in
041-842-117
Wide 90° Diamond
0–7.6 mm (0–0.30 in)
046-198-608
Wide 90° Diamond
7.1–14.2 mm (0.28–0.56 in)
046-198-609
90° Diamond
0–7.1 mm (0–0.28 in)
041-842-016
90° Diamond
4.1–10.9 mm (0.16–0.43 in)
041-842-017
–129°C to 315°C (-200°F to 600°F)
–129°C to 540°C (-200°F to 1000°F)
* The smooth surface wedges are only rated to 40 kN (9.2 kip). † Tolerance for specimen shank flatness is ±.005 in (±.127 mm).
Series 647 Hydraulic Wedge Grips
Introduction
23
‡ The water cooling kit is part number 048-974-801.
Round Specimen Wedges Surface*
Diameter†‡
Part Number (water cooled§)
-40°C to 177°C (-40°F to 350°F) Surfalloy
10.75 mm
(046-838-719)
Surfalloy
12 mm
041-842-134
(046-838-716)
Surfalloy
15 mm
041-842-135
(046-838-716)
Surfalloy
16 mm
Surfalloy
20 mm
041-842-136
Surfalloy
24 mm
041-842-145
Surfalloy
0.5 in
041-842-132
(046-838-714)
Surfalloy
0.75 in
041-842-133
(046-838-715)
Surfalloy
1 in
041-842-149
Smooth
12 mm
041-842-150
Smooth
15 mm
041-842-151
Smooth
20 mm
041-842-146
Smooth
0.5 in
041-842-147
Smooth
1 in
041-842-148
Smooth
11 mm
(046-838-708)
Smooth
15 mm
(046-8387-09)
(046-838-720) (046-838-716)
* The smooth surface wedges are only rated to 40 kN (9.2 kip). † The SI units do not have US customary equivalents (and vice versa). ‡ Allowable tolerance for the specimen shank diameter is ±.001 in (±.0254 mm) for metal specimens, ±.005 in (±.127mm) for plastic/low modulus composite specimens, and ±.0005 in (±.0127 mm) for ceramic specimens. § The water cooling kit is part number 048-974-801.
24
Introduction
Series 647 Hydraulic Wedge Grips
The vee wedge specimen diameter specification represents the diameter range if the specimen is installed from the side of the grips (the widest opening). The specimen diameter also lists the maximum specimen diameter if the specimen is installed from the top of the grips. Vee Specimen Wedges Surface*
When Side/Top Loading†
Part Number (water cooled‡)
-40°C to 177°C (-40°F to 350°F) 90° Diamond
5.8–10.2/11.9 mm (0.23–0.40/0.47 in)
041-842-103
90° Diamond
10.9–12.7/16.5 mm (0.43–0.50/0.65 in)
041-842-104
90° Diamond
17–17/22.9 mm (0.67–0.67/0.9 in)
041-842-110
Smooth
3.0–6.4 mm (0.12–0.12/0.25 in)
041-842-123
Smooth
6.4–11.7/13 mm (0.25–0.46/0.51 in)
041-842-130
Smooth
17–17/22.9 mm (0.67–0.67/0.9 in)
041-842-129
Serrated
5.8–10.2/11.9 mm (0.23–0.40/0.47 in)
(046-838-703)
Serrated
10.9–12.7/16.5 mm (0.43–0.50/0.65 in)
(046-838-704)
Smooth
2–9.4/9.4 mm (0.08–0.37/0.38 in)
(046-838-711)
Smooth
4.5–10.9/11.7 mm (0.18–0.43/0.46 in)
(046-838-710)
–129°C to 315°C (-200°F to 600°F) Serrated
10.9–12.7/16.5 mm (0.43–0.5/0.65 in)
041-842-118
–129°C to 540°C (-200°F to 1000°F) Serrated
5.8–10.2/11.9 mm (0.23–0.4/0.47 in)
041-842-021
Serrated
10.9–12.7/16.5 mm (0.43–0.5/0.65 in)
041-842-022
* The smooth surface wedges are only rated to 40 kN (9.2 kip). † Side load diameter range/maximum top load diameter. ‡ The water cooling kit is part number 048-974-801.
Series 647 Hydraulic Wedge Grips
Introduction
25
Model 647.25 Wedges These wedges fit the Model 647.25 Hydraulic Grip. The usable width of the standard wedges is 50 mm (2 in), or 100 mm (4 in) for the wedges listed as “Wide,” the insertion depth is 89 mm (3.5 in). They are sold in matched sets of four. Flat Specimen Wedges Surface
Specimen Thickness*
Part Number (water cooled†) {24 teeth per inch}
-40°C to 177°C (-40°F to 350°F) 90° Diamond
1.0–11.9mm (0.04–0.47 in)
041-842-201 (045-966-201) {045-966-208}
90° Diamond
6.1–17 mm (0.24–0.67 in)
041-842-202 (045-966-202) {045-966209}
90° Diamond
14.9–25.9 mm (0.59–1.02 in)
041-842-203 (045-966-204) {045-966210}
Wide 90° Diamond
1.0–11.9 mm (0.04–0.47 in)
046-198-804
Wide 90° Diamond
6.1–17 mm (0.24–0.67 in)
046-198-805
Wide 90 Diamond
14.9–25.9 mm (0.59–1.02 in)
046-198-806
Surfalloy
1.0–11.9 mm (0.04–0.47 in)
041-842-207 (045-966205)
Surfalloy
6.1–17 mm (0.24–0.67 in)
041-842-209
Surfalloy
14.9–25.9 mm (0.59–1.02 in)
041-842-207
Wide Surfalloy
1.0–11.9 mm (0.04–0.47 in)
046-198-801
Wide Surfalloy
6.1–17 mm (0.24–0.67 in)
046-198-802
Wide Surfalloy
14.9–25.9 mm (0.59–1.02 in)
046-198-803
Wide Surfalloy‡
1.0–11.9 mm (0.04–0.47 in)
046-198-814
Wide Surfalloy†
6.1–17 mm (0.24–0.67 in)
046-198-816
Wide Surfalloy†
14.9–25.9 mm (0.59–1.02 in)
046-198-815
Smooth
14.9–25.9 mm (0.59–1.02 in)
046-198-807
–129°C to 315°C (-200°F to 600°F)
26
90° Diamond
1–11.9 mm (0.04–0.47 in)
041842-210
90° Diamond
6.1–17 mm (0.24–0.67 in)
041842-211
90° Diamond
14.9–25.9 mm (0.59–1.02 in)
041842-212
Wide 90° Diamond
1–11.9 mm (0.04–0.47 in)
046198-809
Wide 90° Diamond
6.1–17 mm (0.24–0.67 in)
046198-813
Wide 90° Diamond
14.9–25.9 mm (0.59–1.02 in)
046198-810
Introduction
Series 647 Hydraulic Wedge Grips
Flat Specimen Wedges Specimen Thickness*
Part Number (water cooled†) {24 teeth per inch}
90° Diamond
1–11.9 mm (0.04–0.47 in)
041-842-218
90° Diamond
6.1–17 mm (0.24–0.67 in)
041-842-219
90° Diamond
14.9–25.9 mm (0.59–1.02 in)
041-842-220
Surfalloy
1–11.9 mm (0.04–0.47 in)
041-842-240
Surfalloy
6.1–17 mm (0.24–0.67 in)
041-842-241
Surfalloy
14.9–25.9 mm (0.59–1.02 in)
041-842-242
Surface –129°C to 540°C (-200°F to 1000°F)
* Tolerance for specimen shank flatness is ±.005 in (±.127 mm). † The water cooling kit is part number 048-974-801. ‡ These are made of Inconnel.
Round Specimen Wedges Surface
Diameter*†
Part Number
Surfalloy
15 mm
041-842-231
Surfalloy
20 mm
041-842-232
Surfalloy
30 mm
041-842-233
Surfalloy
0.5 in
041-842-234
Surfalloy
1 in
041-842-235
-40°C to 177°C (-40°F to 350°F)
* The SI units do not have US customary equivalents (and vice versa). † Allowable tolerance for the specimen shank diameter is ±.001 in (±.0254 mm) for metal specimens, ±.005 in (±.127mm) for plastic/low modulus composite specimens, and ±.0005 in (±.0127 mm) for ceramic specimens.
Series 647 Hydraulic Wedge Grips
Introduction
27
The vee wedge specimen diameter specification represents the diameter range if the specimen is installed from the side of the grips (the widest opening). The specimen diameter also lists the maximum specimen diameter if the specimen is installed from the top of the grips. Vee Specimen Wedges Surface
When Side/Top Loading*
Part Number (water cooled†)
-40°C to 177°C (-40°F to 350°F) 90° Diamond
6.4–10.2/13.5 mm (0.25–0.40/0.53 in)
041-842-103
(045-966-206)
90° Diamond
10.7–16.8/19.9 mm (0.42–0.66/0.78 in)
041-842-104
(046-838-711)
90° Diamond
16.8–20.0/26.2 mm (0.66–0.79/1.03 in)
045-966-207 (046-838-703)
–129°C to 315°C (-200°F to 600°F) 90° Diamond
6.4–10.2/13.5 mm (0.25–0.40/0.53 in)
041-842-015
90° Diamond
10.7–16.8/19.9 mm (0.42–0.66/0.78 in)
041-842-013
90° Diamond
16.8–20/26.2 mm (0.66–0.79/01.03 in)
041-842-014
–129°C to 540°C (-200°F to 1000°F) 90° Diamond
6.4–10.2/13.5 mm (0.25–0.40/0.53 in)
041-842-223
90° Diamond
10.7–16.8/19.9 mm (0.42–0.66/0.78 in)
041-842-221
90° Diamond
16.8–20/26.2 mm (0.66–0.79/01.03 in)
041-842-222
* Side load diameter range/maximum top load diameter. † The water cooling kit is part number 048-974-801.
28
Introduction
Series 647 Hydraulic Wedge Grips
Model 647.50 Wedges These wedges fit the Model 647.100 Hydraulic Grip. The usable width of the standard wedges is 100 mm (4 in), the insertion depth is 89 mm (3.5 in). They are sold in matched sets of four. Flat Specimen Wedges Specimen Thickness*
Part Number
90° Diamond
0–10.9 mm (0.00–0.43 in)
047-641-606
90° Diamond
10.1–21 mm (0.40–0.83 in)
047-641-607
90° Diamond
20.3–31.2 mm (0.80–1.23 in)
047-641-608
90° Diamond
30.4–41.4 mm (1.20–1.63 in)
047-641-609
90° Diamond
40.6–51.5 mm (1.60–2.03 in)
047-641-610
Surfalloy
0–10.9 mm (0.00–0.43 in)
047-641-611
Surfalloy
10.1–21 mm (0.40–0.83 in)
047-641-612
Surfalloy
20.3–31.2 mm (0.80–1.23 in)
047-641-613
Surfalloy
30.4–41.4 mm (1.20–1.63 in)
047-641-614
Surfalloy
40.6–51.5 mm (1.60–2.03 in)
047-641-615
Surface -40°C to 177°C (-40°F to 350°F)
* Tolerance for specimen shank flatness is ±.005 in (±.127 mm).
The vee wedge specimen diameter specification represents the diameter range if the specimen is installed from the side of the grips (the widest opening). The specimen diameter also lists the maximum specimen diameter if the specimen is installed from the top of the grips. Vee Specimen Wedges Surface
When Side/Top Loading*
Part Number
90° Diamond
6.4–12.7/15.5 mm (0.25–0.50/0.61 in)
047-641-601
90° Diamond
15.2–18.3/24.4 mm (0.60–0.72/0.96 in)
047-641-602
90° Diamond
24.1–25.1/33.5 mm (0.95–0.99/1.32 in)
047-641-603
90° Diamond
33.0–33.0/42.4 mm (1.30–1.30/1.67 in)
047-641-604
90° Diamond
41.9–41.9/51.3 mm (1.65–1.65/2.02 in)
047-641-605
-40°C to 177°C (-40°F to 350°F)
* Side load diameter range/maximum top load diameter.
Series 647 Hydraulic Wedge Grips
Introduction
29
Model 647.100 Wedges These wedges fit the Model 647.100 Hydraulic Grip. The usable width of the standard wedges is 100 mm (4 in), the insertion depth is 89 mm (3.5 in). They are sold in matched sets of four. Flat Specimen Wedges Specimen Thickness*
Part Number
90° Diamond
0–23 mm (0–0.89 in)
053-137-403
90° Diamond
23–45 mm (0.89–1.77 in)
053-137-402
90° Diamond
45–67 mm (1.77–2.64 in)
053-137-401
Surfalloy
0–23 mm (0–0.89 in)
053-137-403
Surfalloy
23–45 mm (0.89–1.77 in)
053-137-402
Surfalloy
45–67 mm (1.77–2.64 in)
053-137-401
Surface -40°C to 177°C (-40°F to 350°F)
* Tolerance for specimen shank flatness is ±.005 in (±.127 mm).
The vee wedge specimen diameter specification represents the diameter range if the specimen is installed from the side of the grips (the widest opening). The specimen diameter also lists the maximum specimen diameter if the specimen is installed from the top of the grips. Vee Specimen Wedges Surface
When Side/Top Loading*
Part Number
90° Diamond
6–10 mm (0.24–0.39 in)
053-137-407
90° Diamond
10–25 mm (0.39–0.99 in)
05-3137-406
90° Diamond
25–44 mm (0.99–1.75 in)
053-137-405
90° Diamond
44–63 mm (1.75–2.5 in)
053-137-404
-40°C to 177°C (-40°F to 350°F)
* Side load diameter range/maximum top load diameter.
30
Introduction
Series 647 Hydraulic Wedge Grips
Installation This section describes how to install and align the Series 647 Hydraulic Wedge Grips.
Contents
Installing Axial Grips
32
Installing Axial-Torsional Grips
36
Installing the Grips in an Environmental Chamber Environmental Chambers with U-Plugs
42
Environmental Chambers Without U-Plugs Installing Extension Rods
WARNING
41
46
56
Aligning the Wedge Openings
62
Preloading the Spiral Washers
63
Grip installation is dangerous because it occurs within the crush zone of the force train while full hydraulic pressure is applied and actuator movement is required during the installation. Unexpected actuator movement can cause personal injury and damage to the equipment. Take every precaution to avoid unexpected actuator movement while installing the grips.
Series 647 Hydraulic Wedge Grips
Installation
31
Installing Axial Grips Installing the grips in a load unit force train involves attaching one grip onto the end of the actuator rod and one grip to the force transducer. The grips are mounted to the load unit with conductor studs. The following figure shows the components used for most installations. Crosshead or Force Transducer
Shim Washer
Spiral Washer Set Stud 647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
Spiral Washer Set
Shim Washer Actuator Rod
Stud Load Unit Base Plate
Axial Grip Installation Components
Required equipment
32
Installation
The following materials and equipment are required for installation: •
The appropriate attachment kit
•
Two sets of spiral washers
•
Two connector studs
•
Shim washers
•
Lubricant; see the “Temperature ranges” on page 13 for the recommended lubricant
•
Appropriately sized eyebolts, adequately sized wood blocks and plywood sheet (or equivalent), and an appropriately sized lifting device, see “Grip Dimensions” on page 18.
Series 647 Hydraulic Wedge Grips
Installation procedure
The following procedure assumes the actuator is mounted in the base of the load unit and the force transducer is mounted to the crosshead. If you have a load unit with the actuator mounted to the crosshead, make the appropriate changes to the following procedure. See the figure “Axial Grip Installation Components” on page 32. 1. Set up the load unit. A.
Turn on the system hydraulic pressure.
B.
Adjust the actuator and crosshead position as necessary to allow adequate room to install the grips.
C.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
D. Lubricate all of the surfaces that will contact each other (screw threads, spacers, etc.). See “Temperature ranges” on page 13 for the recommended lubricant. 2. Mount the lower grip. Mount the lower grip to the actuator piston rod. Thread the stud into the lower grip. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding. A.
Add any required shims, spacer, or spiral washers to the stud.
B.
The attachment kit drawing shows what components (such as shims, spiral washers, etc.) should be installed.
C.
Position the lower grip to align it with the connecting stud and stabilize the grip. •
Place appropriately sized wood blocks across the load unit base plate, on opposite sides of the actuator piston rod.
•
For heavy grips, insert the eyebolts into the threaded holes provided on the grip chamber. Attach a lifting device to the eyebolts and carefully raise the grip.
D. Turn on hydraulic pressure and raise the actuator rod until it just makes contact with the connector stud. Reposition the grip, as necessary, to center the stud over the actuator rod. E.
Slowly screw the grip into the actuator rod, raising the actuator rod as you go, until it is snug. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
F.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
Series 647 Hydraulic Wedge Grips
Installation
33
3. Mount the upper grip. Mount the upper grip to the force transducer on the crosshead. See the figure “Axial Grip Installation Components” on page 32. Note
WARNING
Ensure that the force transducer is properly aligned (see your load unit manual).
A.
Thread a stud into the upper grip.
B.
Place a wooden spacer (a wood block or piece of plywood) on top of the lower grip. The wooden spacer should be large enough to cover the diameter of the grip.
The upper grips are very top heavy and will have a tendency to tip over when lifted by the eyebolts. Dropped grips can cause injury to personnel and damage to equipment. Never attempt to control the grip by holding onto the eyebolts. Use the connector stud to help control the grip balance.
Note
C.
The upper grip might need help to balance it on the wooden spacer on the lower grip.
Carefully position the grip on top of the wooden spacer on the lower grip. You might need to insert eyebolts into the threaded holes on the grip chamber. Attach a lifting device to the eyebolts and position the grip on top of the lower grip.
D. With the connector stud is facing up. Add any required shims, spacers, or spiral washers to the stud. E.
Turn on hydraulic pressure and slowly raise the lower grip until the stud on the upper grip just makes contact with the force transducer. Reposition the grip as necessary for proper thread alignment.
F.
Slowly screw the grip into the force transducer until it is snug.
4. Align the grip wedge openings. See “Aligning the Wedge Openings” on page 62 and check the alignment between the upper and lower grips. Align the lower grip as necessary for the desired hose connection and wedge opening orientation. If the actuator rod cannot be rotated, remove the lower grip and install one or more shim washers between the spiral washers and the lower element of the force train. Reinstall the grip (go to Step 2). Align the upper grip wedge opening with the lower grip wedge opening. If proper alignment is not possible, remove the upper grip and install one or more shim washers between the spiral washers and the upper element of the force train. Reinstall the grip (go to Step 3).
34
Installation
Series 647 Hydraulic Wedge Grips
5. Connect the hydraulics. Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving. Using the provided hydraulic hoses, make connections between the pressure and release ports on the grip and the pressure and release ports on the load unit or the external hydraulic grip supply. See your load unit product manual or hydraulic grip control manual for their port locations. 6. Tighten the grips. See “Preloading the Spiral Washers” on page 63 to preload the connector stud and return to this procedure when done. 7. Install the wedges. Go to “Changing Wedges” on page 70 for the procedure to install wedges into the grips. This completes the axial grips installation.
Series 647 Hydraulic Wedge Grips
Installation
35
Installing Axial-Torsional Grips Installing the grips in a load unit force train involves attaching one grip onto the end of the actuator rod and one grip to the force transducer or crosshead. The grips are mounted to the load unit with conductor studs. The following figure shows the components used for most installations. Crosshead
Force Transducer Adapter Socket Head Cap Screw
Left Hand Thread Upper Coupling
Upper Coupling
1.5 kN Axial Rating Torsional 220 N-m 1. Insert bolts, finger tight. 2. Turn coupling Actuator to tighten joint. 3. Torque bolts
Grip/Fixtur
Right Hand Thread Clamp Pressure Release Pressure
Release Pressure Clamp Pressure
647 Hydraulic Wedge Grip
Upper Grip
647 Hydraulic Wedge Grip
Lower Grip
Left Hand Thread Lower Coupling
Lower Coupling Actuator Rod
Axial Rating Torsional
1.5 kN 220 N-m
1. Insert bolts, finger tight. 2. Turn coupling Grip/Fixtur e to tighten joint. 3. Torque bolts
Right Hand Thread Load Unit Base Plate
Axial-Torsional Grip Installation Components
Required equipment
36
Installation
•
The appropriate attachment kit (includes a drawing showing what components should be installed).
•
Lubricant, (see “Temperature ranges” on page 13 for the recommended lubricant).
•
Appropriately sized eyebolts, adequately sized wood blocks and plywood sheet (or equivalent), and an appropriately sized lifting device, see “Grip Dimensions” on page 18.
Series 647 Hydraulic Wedge Grips
Prerequisites
If you are installing the grip on an axial-torsional force transducer, perform the force transducer alignment procedure before proceeding (see the appropriate load unit product manual).
Installation procedure
The following procedure assumes the actuator is mounted in the base of the load unit and the force transducer is mounted to the crosshead. If you have a load unit with the actuator mounted to the crosshead, make the appropriate changes to the following procedure. See the figure “Axial-Torsional Grip Installation Components” on page 36 during this procedure. Note
Although it is possible for the grips to be installed by one person we recommend using two people to lift, handle, and position the grips.
1. Set up the load unit. A.
Turn on the system hydraulic pressure.
B.
Adjust the actuator and crosshead position as necessary to allow adequate room to install the grips.
C.
Select rotation control and adjust the actuator to the mid-rotation position.
D. Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving. E.
Clean and lubricate all of the surfaces that will contact each other (screw threads, spacers, etc.). Clean the surfaces with alcohol or similar decreasing solvent. Lubricate the parts with Molykote G-n paste.
2. Mount the lower grip. Mount the lower grip to the actuator piston rod using the actuator-togrip coupling. A.
Note
B.
Series 647 Hydraulic Wedge Grips
Remove the socket head cap screws from the lower coupling and place the screws and coupling halves within easy reach and oriented properly for installation on the grips. The label on the coupling indentifies which component should be connected to each side of the coupling. Each end of the coupling has different threads.
Position the lower grip to align it with the connecting stud on the actuator and stabilize the grip. •
Place appropriately sized wood blocks across the load unit base plate, on opposite sides of the actuator piston rod.
•
For heavy grips, insert the eyebolts into the threaded holes provided on the grip chamber. Attach a lifting device to the eyebolts and carefully raise the grip.
Installation
37
C.
Select the lower grip coupling set. Place the lower grip coupling half with the threaded holes against the actuator and grip threads. Rotate it back and forth, as necessary, until the threads mesh with the actuator and grip threads.
D. Place the other coupling half against the actuator and grip threads. While holding the two halves together thread the socket head cap screws into the coupling until they are finger tight. E.
Check both ends of the coupling to ensure the gap between the two halves is approximately equal. If necessary, tighten and loosen the socket head cap screws to achieve this.
F.
Find the label on the coupling. This label indicates the direction to tighten, the rotation pattern for tightening the cap screws, and other important information. The illustration is an example only.
G. With all the socket head cap screws finger tight, rotate the coupling assembly in the direction shown on the coupling label until it is tight. This preloads the grip connection. H. Tighten the socket head cap screws in the order shown on the coupling label, first to 10%, then to 50% and finally to 100% of the specified torque.
1
Lower Coupling
1. Insert bolts, finger tight. 2. Turn coupling
3
4
25 kN 220 N-m
Axial Rating Torsion Rating
Grip/Fixture
to tighten joint 3. Torque bolts 11 ft-lbs / 14.9 N-m.
Actuator
2
MTS Systems Corporation Mpls., MN. Patent Pending PN 466350-01
Numbers show the rotation pattern.
Full (100%) torque listed here.
3. Mount the upper grip. Mount the upper grip to the force transducer on the crosshead using an adapter between the force transducer and the upper grip. A.
Place the load transducer mating adapter against the force transducer and thread the socket head cap screws into the force transducer until they are finger tight.
B.
Using the sequence shown in the figure to the right, torque the socket head screws first to 10%, then to 50%, and finally to 100% of the torque specified on the attachment kit drawing (MTS part number 469615-xx).
C.
8
1
5
4
3
6
2 Remove the socket head cap screws from the upper coupling and place the screws and coupling halves within easy reach and oriented properly for installation on the grips.
7
D. Place a wooden spacer (a wood block or piece of plywood) on top of the lower grip. The wooden spacer should be large enough to cover the diameter of the grip.
38
Installation
Series 647 Hydraulic Wedge Grips
WARNING
The upper grips are very top heavy and will have a tendency to tip over when lifted by the eyebolts. Dropped grips can cause injury to personnel and damage to equipment. Never attempt to control the grip by holding onto the eyebolts. Use the connector stud to help control the grip balance.
Note
You will need to construct a proper support or have someone available to help balance the upper grip on the lower grip. Load Unit Crosshead Force Transducer
Load Unit Columns
Adapter Plate
Upper Coupling Axial Rating 250 kN 2200 N-m Torsion 1. InsertRating bolts, finger tight. 2. Turn coupling Force Xdcr to tighten joint Grip/Fixture 3. Torque bolts 94 ft-lbs / 127 N-m.
MTS Systems Corporation Mpls., MN. Patent Pending PN 466350-02
Upper Coupling
l
646 Hydraulic Collet Grip
Upper Grip
Wood Block Lower Grip l
646 Hydraulic Collet Grip
Lower Coupling Axial Rating 250 kN 2200 N-m Torsion Rating 1. Insert bolts, finger tight. 2. Turn coupling Grip/Fixture to tighten joint 3. Torque bolts 94 ft-lbs / 127 N-m.
Lower Coupling
Actuator
MTS Systems Corporation Mpls., MN. Patent Pending PN 466350-01
Load Unit Base Plate
E.
Actuator Piston Rod
Carefully position the grip on top of the wooden spacer on the lower grip. You might need to insert eyebolts into the threaded holes on the grip chamber. Attach a lifting device to the eyebolts and position the grip on top of the lower grip.
F.
Select the upper coupling set. Place the coupling half with the threaded holes against the adapter and grip threads. Rotate it back and forth, as necessary, until the threads mesh with the actuator and grip threads.
G. Place the other coupling half against the actuator and grip threads. While holding the two halves together, thread the socket head cap screws into the coupling until they are finger tight. H. Check both ends of the coupling to ensure the gap between the two halves is approximately equal. If necessary, tighten and loosen the socket head cap screws to achieve this.
Series 647 Hydraulic Wedge Grips
Installation
39
4. Tighten the grips. A.
Find the label on the coupling. This label shows the direction to tighten, the rotation pattern for tightening the cap screws, and other important information. The illustration is an example only.
B.
With all of the socket head cap screws finger tight, rotate the coupling assembly in the direction shown on the label until it is tight. This is essential to ensure proper preloading of the coupling.
C.
Tighten the socket head cap screws in the rotation pattern shown on the label, first to 10%, then to 50%, and finally to 100% of the torque specified on the label.
5. Connect the hydraulics.
1
Upper Coupling Axial Rating Torsion Rating
25 kN 220 N-m
1. Insert bolts, finger tight. 2. Turn coupling
3
to tighten joint 3. Torque bolts 11 ft-lbs / 14.9 N-m.
4
Force Xdcr Grip/Fixture
2
MTS Systems Corporation Mpls., MN. Patent Pending PN 466350-02
Numbers show the rotation pattern.
Full (100%) torque listed here.
Using the provided hydraulic hoses, make connections between the pressure and release ports on the grip and the pressure and release ports on the load unit or the external hydraulic grip supply. See the your load unit product manual or hydraulic grip control manual for their port locations. 6. Install the wedges. See “Changing Wedges” on page 70 for the procedure to install wedges into the grips. This completes the axial-torsional grip installation.
40
Installation
Series 647 Hydraulic Wedge Grips
Installing the Grips in an Environmental Chamber The all-temperature grips are designed to be used over a wide range of temperatures. To achieve a given temperature, an environmental chamber is needed. Environmental chambers are available with or without U-plugs. A U-plug is a removable panel that allows the chamber to be installed after the grips are installed. •
If the environmental chamber has upper and lower U-plugs, install the grips first, then install the environmental chamber. Simply remove the U-plugs from the chamber, move the environmental chamber around the grips and reinstall the U-plugs.
Lower U-plug
Go to “Environmental Chambers with U-Plugs” on page 42. •
If the environmental chamber has no U-plugs, the environmental chamber must installed first. Then the grips must be partially disassembled and reassembled after the environmental chamber is installed. Go to “Environmental Chambers Without U-Plugs” on page 46.
Note
Required equipment
See the environmental chamber product manual for additional information.
Equipment and materials required to install the all temperature grips include: •
The appropriate attachment kit includes the components to install the grips
•
Appropriately sized device to lift the heavier grips
•
Appropriately sized eyebolts and wood blocks or plywood sheet for lifting the heavier grips
•
Lubricant; see “Temperature ranges” on page 13 for the recommended lubricant
•
Hydraulic plumbing capable of withstanding the temperature extremes
•
An environmental chamber
•
A heating/cooling kit
•
A tool kit is provided with each set of grips. It contains a set of spare extension springs for securing the wedges in the grip, a utility hook, the tools required to disassemble the grip, and eye bolts and a swivel eye for installing and removing the grips.
Series 647 Hydraulic Wedge Grips
Installation
41
Environmental Chambers with U-Plugs Environmental chambers that have U-plugs can be installed after the grips are installed. The following figure shows the components used for most installations.
Force Transducer Shim Washer
Spiral Washer Set
Connector Stud
Hydraulic Release 647 Hydraulic Wedge Grip
Hydraulic Pressure Upper Grip Assembly Environmental Chamber
Lower Grip Assembly Water Supply Hydraulic Release 647 Hydraulic Wedge Grip
Hydraulic Pressure
Shim Washer Actuator Rod Load Unit Base Plate
Connector Stud Spiral Washer Set
All-Temperature Grip Installation Components
42
Installation
Series 647 Hydraulic Wedge Grips
Installation procedure
The following procedure assumes the actuator is mounted in the base of the load unit and that the force transducer is mounted to the crosshead. If you have a load unit with the actuator mounted to the crosshead, make the appropriate changes to the following procedure. See the figure “Axial-Torsional Grip Installation Components” on page 36 during this procedure. 1. Set up the load unit. A.
Turn on the system hydraulic pressure.
B.
Adjust the actuator and crosshead positions as necessary to allow adequate room to install the grips.
C.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
D. Clean and lubricate all of the surfaces that will contact each other (screw threads, spacers, etc.). Clean the surfaces with alcohol or similar decreasing solvent. See “Temperature ranges” on page 13 for the recommended lubricant. 2. Mount the lower grip. Mount the lower grip to the actuator piston rod using the appropriate stud, shims, spacer, or spiral washers. A.
Place a small piece of compliant material in the threaded hole of the grip and thread the stud into the lower grip. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Add any required shims, spacer, or spiral washers to the stud. The attachment kit drawing shows what components (such as shims, spiral washers, etc.) should be installed.
C.
Position the lower grip to align it with the connecting stud and stabilize the grip. •
Place appropriately sized wood blocks across the load unit base plate, on opposite sides of the actuator piston rod.
•
For heavy grips, insert the eyebolts into the threaded holes provided on the grip chamber. Attach a lifting device to the eyebolts and carefully raise the grip.
D. Turn on hydraulic pressure and raise the actuator rod until it just makes contact with the connector stud. Reposition the grip, as necessary, to center the stud over the actuator rod.
Series 647 Hydraulic Wedge Grips
Installation
43
E.
Slowly screw the grip into the actuator rod, raising the actuator rod as you go, until it is snug. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
F.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
3. Mount the upper grip. Mount the upper grip to the force transducer on the crosshead using the appropriate stud, shims, spacer, or spiral washers. See the figure “Axial-Torsional Grip Installation Components” on page 36. Note
WARNING
Ensure the force transducer is properly aligned (see your load unit manual).
A.
Thread the stud into the upper grip.
B.
Place a wooden spacer (a wood block or piece of plywood) on top of the lower grip. The wooden spacer should be large enough to cover the diameter of the grip.
The upper grips are very top heavy and will have a tendency to tip over when lifted by the eyebolts. Dropped grips can cause injury to personnel and damage to equipment. Never attempt to control the grip by holding onto the eyebolts. Use the connector stud to help control the grip balance.
Note
C.
You will need to construct a proper support or have someone available to help balance the upper grip on the lower grip.
Carefully position the grip on top of the wooden spacer on the lower grip. You might need to insert eyebolts into the threaded holes on the grip chamber. Attach a lifting device to the eyebolts and position the grip on top of the lower grip.
D. With the connector stud is facing up. Add any required shims, spacers, or spiral washers to the stud.
44
Installation
E.
Turn on hydraulic pressure and slowly raise the lower grip until the stud on the upper grip just makes contact with the force transducer. Reposition the grip, as necessary, for proper thread alignment.
F.
Slowly screw the grip into the force transducer until it is snug.
Series 647 Hydraulic Wedge Grips
4. Align the grip wedge openings. See “Aligning the Wedge Openings” on page 62 for more information. Align the lower grip as necessary for the desired hose connection and wedge opening orientation. If the actuator rod cannot be rotated, remove the lower grip and install one or more shim washers between the spiral washers and the lower element of the force train. Reinstall the grip (go to Step 2). Align the upper grip wedge opening with the lower grip wedge opening. If proper alignment is not possible, remove the upper grip and install one or more shim washers between the spiral washers and the upper element of the force train. Reinstall the grip (go to Step 3). 5. Connect the hydraulics. Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving. Using the provided hydraulic hoses, make connections between the pressure and release ports on the grip and the pressure and release ports on the load unit or on the external hydraulic grip supply. See your load unit product manual or hydraulic grip control manual for their port locations. 6. If needed, connect the water supply. Water can heat or cool the grips. A.
Mount the water valve clamp to a load unit column.
B.
Connect water lines (supply and drain) between the water lines attached to the columns and the upper and lower grips.
C.
Connect the water supply (and drain) to the water valve/drain mounted to the load unit columns.
7. Tighten the grips. See “Preloading the Spiral Washers” on page 63 to preload the connector stud. Return to this procedure when done. 8. Install the environmental chamber. Position the environmental chamber (with its cart) in the load unit so the actuator extends through the chamber’s U-plugs. Secure the cart and install the U-plugs. Refer to the environmental chamber documentation for more information. 9. Install the wedges. Go to “Changing Wedges” on page 70 for the procedure to install wedges into the grips. This completes the grips installation.
Series 647 Hydraulic Wedge Grips
Installation
45
Environmental Chambers Without U-Plugs Environmental chambers that do not have U-plugs must be installed before the grips are installed. The grips must be partially disassembled to install them. The following figure shows the components of the grip assembly.
Hydraulic Chamber
Cylinder
Piston Extension
Eye Bolt Holes (4)
Eye Bolt Holes (2)
Wedge Chamber
Socket Head Bolt
All-Temperature Grip Component Assemblies
46
Installation
Series 647 Hydraulic Wedge Grips
WARNING
The grips and their components can be heavy, which can make handling them awkward. Dropping a grip or one of its components can cause injury to personnel and damage to equipment. Ensure that you take appropriate precautions while moving and positioning the grips and their components.
Grip component weights Model
The following table lists the approximate weights for the components of the all-temperature grips.
Wedge Chamber
Cylinder
Piston Extension
Hydraulic Chamber
Assembled Weight
647.02
top bottom
6 kg (13 lb) 6 kg (13 lb)
1.3 kg (3 lb) 2 kg (4.5 lb)
3 kg (6 lb) 4 kg (9 lb)
5.1 kg (11 lb) 5.1 kg (11 lb)
15 kg (33 lb) 17 kg (38 lb)
647.10
top bottom
24 kg (52 lb) 24 kg (52 lb)
3 kg (7 lb) 5 kg (11 lb)
7 kg (16 lb) 12 kg (26 lb)
16 kg (34 lb) 16 kg (34 lb)
57 kg (125 lb) 64 kg (142 lb)
647.25
top bottom
72 kg (158 lb) 72 kg (158 lb)
5 kg (11 lb) 7 kg (16 lb)
17 kg (37 lb) 24 kg (53 lb)
37 kg (82 lb) 37kg (82 lb)
131 kg (288 lb) 141 kg (310 lb)
Series 647 Hydraulic Wedge Grips
Installation
47
Installation procedure
The following procedure assumes the actuator is mounted in the base of the load unit and the force transducer is mounted to the crosshead. If you have a load unit with the actuator mounted to the crosshead, make the appropriate changes to the following procedure. Refer to the figures “Axial-Torsional Grip Installation Components” on page 36 and “All-Temperature Grip Component Assemblies” on page 46 during this procedure. 1. Set up the load unit. A.
Turn on the system hydraulic pressure.
B.
Position the actuator and crosshead as necessary to allow adequate room to install the grips.
C.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
2. Disassemble the grips. A.
Place both grips on a clean work surface near the load unit. Note the difference in length. The longer grip is the lower grip and the shorter grip is the upper grip. Lay both grips on their side and block, as necessary, to prevent them rolling while being worked on.
B.
If necessary, remove the wedges from each grip. Go to “Changing Wedges” on page 70 and return to this procedure when done.
C.
Separate the hydraulic chamber from the grip assembly. Remove the socket head bolt which secures the piston extension to the hydraulic chamber. Perform this step for both grips.
D. If necessary attach a strap wrench to the cylinder and the hydraulic chamber. Unscrew the hydraulic chamber from the cylinder. Perform this step for both grips. E.
Clean and lubricate all of the surfaces that will contact each other (screw threads, spacers, etc.). Clean the surfaces with alcohol or similar decreasing solvent. See “Temperature ranges” on page 13 for the recommended lubricant.
48
Installation
Series 647 Hydraulic Wedge Grips
3. Mount the hydraulic chamber of the lower grip. Mount the hydraulic chamber of the lower grip to the actuator piston rod using the appropriate stud, shims, and spiral washers. Hydraulic Chamber
Connector Stud
Load Unit Columns
647 Hydraulic Wedge Grip
Lifting Device Spiral Washers
Shim Washer Load Unit Base Plate
Actuator Rod
A.
Thread the connector stud into the hydraulic chamber of the lower grip. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Add any required shims, spacer, or spiral washers to the stud. The attachment kit drawing shows what components (such as shims, spiral washers, etc.) should be installed.
C.
Position the lower grip to align it with the connecting stud and stabilize the grip. •
Place appropriately sized wood blocks across the load unit base plate, on opposite sides of the actuator piston rod.
•
For heavy grips, insert the eyebolts into the threaded holes provided on the grip chamber. Attach a lifting device to the eyebolts and carefully raise the grip.
D. Turn on hydraulic pressure and raise the actuator rod until it just makes contact with the connector stud. Reposition the grip, as necessary, to center the stud over the actuator rod. E.
Slowly screw the grip into the actuator rod, raising the actuator rod as you go, until it is snug. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
F.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
Series 647 Hydraulic Wedge Grips
Installation
49
4. Mount the hydraulic chamber of the upper grip. Mount the upper grip to the force transducer on the crosshead using the appropriate stud, shims, spacer, or spiral washers. Note
Ensure the force transducer is aligned (see your load unit manual).
A.
Thread the stud into the upper grip. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Place a wooden spacer (a wood block or piece of plywood) on top of the lower grip. The wooden spacer should be large enough to cover the diameter of the grip.
Load Unit Crosshead Force Transducer Spiral Washers
Connector Stud 647 Hydraulic Wedge Grip
Hydraulic Chamber
Wood Block
Lifting Device Load Unit Columns
647 Hydraulic Wedge Grip
Actuator Rod Load Unit Base Plate
WARNING
The upper grips are very top heavy and will have a tendency to tip over when lifted by the eyebolts. Dropped grips can cause injury to personnel and damage to equipment. Never attempt to control the grip by holding onto the eyebolts. Use the connector stud to help control the grip balance.
Note
C.
You will need to construct a proper support or have someone available to help balance the upper grip on the lower grip.
Carefully position the grip on top of the wooden spacer on the lower grip. You might need to insert eyebolts into the threaded holes on the grip chamber. Attach a lifting device to the eyebolts and position the grip on top of the lower grip.
50
Installation
Series 647 Hydraulic Wedge Grips
D. With the connector stud is facing up. Add any required shims, spacers, or spiral washers to the stud. E.
Turn on hydraulic pressure and slowly raise the lower grip until the stud on the upper grip just makes contact with the force transducer. Reposition the grip, as necessary, for proper thread alignment.
F.
Slowly screw the grip into the force transducer until it is snug.
G. Raise the crosshead to accommodate the environmental chamber. 5. Install the environmental chamber. Position the environmental chamber (with its cart) in the load unit so the holes in the chamber are aligned with the force train. Secure the cart. Note
The environmental chamber might need to be repositioned to achieve proper alignment with the grip components.
See the environmental chamber documentation for more information.
Eurotherm
Series 647 Hydraulic Wedge Grips
Installation
2404
51
6. Install the cylinder assemblies and piston extensions. Once the hydraulic chambers of the grips and the environmental chamber are installed, the cylinder and piston extensions can be installed. A.
Lubricate the threads of the lower hydraulic chamber.
B.
Lubricate the threads and the interior wall of the cylinder.
C.
Position the cylinder assembly of the lower grip into the environmental chamber. Move the cylinder assembly through the hole in the environmental chamber. Align it with the threads of the hydraulic chamber.
Upper Hydraulic Chamber 647 Hydraulic Wedge Grip
Environmental Chamber Piston Extension Socket Head Bolt Cylinder Assembly
647 Hydraulic Wedge Grip
Lower Hydraulic Chamber
D. Rotate the cylinder until you feel the thread ends engage. Hand tighten the cylinder to the hydraulic chamber until it is snug. E.
Lubricate the entire lower and bottom end of the piston extension. Also lubricate the threads of the socket head bolt. Insert the socket head bolt into the piston extension.
F.
Slide the piston extension into the cylinder (narrow end first).
G. Thread the socket head bolt into the hydraulic chamber. Do not tighten it at this time. H. Repeat this Step A through Step G for the upper cylinder assembly and piston extension. Note
52
Installation
The piston might slide out of the cylinder when the cylinder end is pointed down.
Series 647 Hydraulic Wedge Grips
7. Install the lower wedge chamber. Installing the lower wedge chamber completes the reassembly of the lower grip. A.
B. Note
C.
Install the eye bolts on the side of the wedge chamber.
647 Hydraulic Wedge Grip
Attach a lifting strap to the eye bolts.
Upper Hydraulic Chamber Cylinder Assembly
Ensure that you stabilize the wedge assembly while you install it.
Lower Wedge Chamber
Position the lower wedge assembly in the environmental chamber using a lifting device if needed.
Cylinder Assembly
647 Hydraulic Wedge Grip
D. Lower the wedge chamber until it contacts the cylinder assembly.
Lower Hydraulic Chamber
E.
Remove the lifting strap and eye bolts.
F.
Rotate the wedge chamber until you feel the threads engage. Slowly screw the cylinder into the piston extension.
8. Install the upper wedge chamber. Installing the upper wedge chamber completes the reassembly of the upper grip. A.
Install the eye bolts on the top of the wedge chamber.
B.
Attach a lifting strap to the eye bolts.
C.
Place a wood block on top of the lower wedge chamber.
Note
647 Hydraulic Wedge Grip
Cylinder Assembly Upper Wedge Chamber
Ensure that you stabilize the wedge assembly while you install it.
D. Position the upper wedge assembly in the environmental chamber using a lifting device if needed.
Series 647 Hydraulic Wedge Grips
Upper Hydraulic Chamber
Wood Block 647 Hydraulic Wedge Grip
Lower Grip Assembly
Installation
53
E.
Place the upper wedge chamber on the wood block.
F.
Remove the lifting strap and eye bolts.
G. Turn on hydraulic pressure. H. Adjust the actuator to raise the upper wedge chamber until it contacts the upper cylinder. I.
Rotate the wedge chamber until you feel the threads engage. Slowly screw the cylinder into the piston extension.
9. Align the grip wedge openings Go to “Aligning the Wedge Openings” on page 62 to align and tighten the grips then return to this procedure. The upper and lower grips must be aligned so the wedge openings are parallel (within ±1°). Align the lower grip as necessary for the desired hose connection and wedge opening orientation. If the actuator rod cannot be rotated, remove the lower grip and install one or more shim washers between the spiral washers and the lower element of the force train. Reinstall the grip. Align the upper grip wedge opening with the lower grip wedge opening. If proper alignment is not possible, remove the upper grip and install one or more shim washers between the spiral washers and the upper element of the force train. Reinstall the grip. 10. Connect the hydraulics. Typically, the shorter set of hard-line tubing is attached to the extension rod connected to the fixed end of the force train (the crosshead); the longer set is attached to the extension rod connected to the moving end (the actuator rod).
54
Installation
•
The Model 647.02 and 647.10 Hydraulic Wedge Grips require hydraulic pressure of 21 MPa (3000 psi). These grips can use the hydraulic power from the load unit or from a Model 685.22 Hydraulic Grip Supply.
•
The Model 647.25/.50/.100 Hydraulic Wedge Grip requires hydraulic pressure of 69 MPa (10000 psi). This grip must be connected to a Model 685.10 or 685.60 Hydraulic Grip Supply.
A.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
B.
Using the provided hydraulic hose, make connections between the pressure (labeled “P”) and release (labeled “R”) fittings on the upper hydraulic chamber and the pressure and release outlets for the upper grip on the hydraulic grip supply.
Series 647 Hydraulic Wedge Grips
C.
Using the provided hydraulic hose, make connections between the pressure (labeled “P”) and release (labeled “R”) fittings on the lower hydraulic chamber and the pressure and release outlets for the lower grip on the hydraulic grip supply.
11. If necessary, connect the water supply. Water is used to heat or cool the grips. Note
Two water manifolds are supplied, one for each grip. Mount a water manifold on each column to keep the temperature of each column balanced.
A.
Mount one water valve clamp to a load unit column. Mount the other water valve clamp to the other load unit column.
B.
Connect water lines (supply and drain) between the water lines attached to the columns and the upper and lower grips.
C.
Connect the water supply (and drain) to the water valve/drain mounted to the load unit columns.
Warming/Cooling Water Return Loop Hydraulic Chamber of Grip Shutoff Valve Water Manifold Warming/Cooling Water Kit Mounting Bracket
From Warming/Cooling Water Supply
Load Unit Column
To Warming/Cooling Water Drain
12. Install the wedges. Go to “Changing Wedges” on page 70 for the procedure to install wedges into the grips. This completes the grips installation.
Series 647 Hydraulic Wedge Grips
Installation
55
Installing Extension Rods The Model 647 Hydraulic Wedge Grips can have extension rods mounted so the grips can be inside an environmental chamber for testing at extreme temperatures. Installing the grips in a load unit with an environmental chamber involves attaching the grips to the end of the actuator rod and the force transducer or crosshead using extension rods. The grips are mounted to the extension rods which are mounted to the load unit with conductor studs or socket head screws. The following figure shows the components used for most installations. Force Transducer or Load Unit Crosshead Shim Washer
Connector Stud
Spiral Washer Set
Upper Extension Rod To Water Valve
Environmental Chamber Top
Water to Lower Extension Rod Hydraulic Pressure and Return Lines
l
647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
Hydraulic Pressure and Return Lines
Environmental Chamber Bottom Hydraulic Pressure and Return Lines Load Unit Base Plate
To Upper Extension Rod To Water Drain Connection Lower Extension Rod Actuator Rod
Extension Rod Installation Components
56
Installation
Series 647 Hydraulic Wedge Grips
The following procedure provides general guidelines for installing the Model 647 Grips in an environmental chamber. See your load unit product manual for the required clearances between moving parts of the force train.
High temperature equipment
Installation procedure
Using an environmental chamber requires: •
Hydraulic plumbing capable of withstanding the temperature extremes
•
Extension rods which are connected to the grip and extend through the environmental chamber for connection to the rest of the force train
•
A heating/cooling kit
•
A self contained hydraulic grip supply with high-temperature hydraulic fluid
The following procedure assumes that the actuator is mounted in the base of the load unit and the force transducer is mounted to the crosshead. If you have a load unit with the actuator mounted to the crosshead, make the appropriate changes to the following procedure. Refer to the figure “Extension Rod Installation Components” on page 56. 1. Set up the load unit. A.
Turn on the system hydraulic pressure.
B.
Adjust the actuator and crosshead position as necessary to allow adequate room to install the environmental chamber and grips.
C.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
D. Lubricate all of the surfaces that will contact each other (screw threads, spacers, etc.). See “Temperature ranges” on page 13 for the recommended lubricant. E.
Install the environmental chamber. See the environmental chamber product manual for installation instructions.
Series 647 Hydraulic Wedge Grips
•
If the environmental chamber has a U-plug in the top and bottom of it, simply remove the U-plug and move the chamber out of the way before installing the grips.
•
If no U-plug is present, the environmental chamber must be properly positioned before installing the grips.
Installation
57
2. Install the extension rods. Note
If the extension rods must be installed through the hole in the environmental chamber, remove the fittings from the end of the hydraulic hard-line tubing which will pass through the hole and remove any cooling water lines connected to the extension rods.
A.
Slowly turn a connector stud into the end of the upper extension rod nearest the cooling water ports. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Place a set of spiral washers over the connector stud on the upper extension rod. Rotate the washers until they are fully closed (minimum thickness). If necessary, rotate the hydraulic hard-line tubing so that the bend is against the extension rod.
C.
Slowly screw the connector stud of the upper extension rod into the force transducer or crosshead until it is snug against the spiral washers.
D. Align the upper extension rod as necessary for desired hose connector orientation. If the desired orientation is not possible, remove the extension rod and install one or more shim washers between the spiral washers and the force transducer or crosshead. Reinstall the extension rod. E.
Slowly screw a connector stud into the actuator rod. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
F.
Place a set of spiral washers over the connector stud in the actuator rod. Rotate the washers until they are fully closed (minimum thickness). If necessary, rotate the hydraulic hard-line tubing so that the bend is against the extension rod.
G. Slowly screw the extension rod onto the connected screw in the actuator until it is snugged tight against the spiral washers. H. Align the lower extension rod as necessary for desired hose connector orientation by rotating the actuator rod. If the actuator rod does not rotate, remove the extension rod and install one or more shim washers between the spiral washers and the actuator rod.
58
Installation
Series 647 Hydraulic Wedge Grips
3. Mount the lower grip. Mount the lower grip to the extension rod connected to the actuator piston rod using the appropriate stud, shims, and spiral washers. A.
Thread the stud into the lower extension rod. The connector stud should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Add any required shims, spacer, or spiral washers to the stud. The attachment kit drawing shows what components (such as shims, spiral washers, etc.) should be installed.
Note
C.
Ensure that you stabilize the wedge assembly while you install it.
Position the lower grip to align it with the connecting stud. •
Place appropriately sized wood blocks across the load unit base plate, on opposite sides of the actuator piston rod.
•
For heavy grips, insert the eyebolts into the threaded holes provided on the grip chamber. Attach a lifting device to the eyebolts and carefully raise the grip.
D. Turn on hydraulic pressure and raise the actuator rod until the extension rod just makes contact with the connector stud. Reposition the grip, as necessary, to center the stud over the extension rod. E.
Slowly screw the grip into the actuator rod, raising the actuator rod as you go, until it is snug. If any resistance is encountered, disassemble and correct the problem before proceeding
F.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
4. Mount the upper grip. Mount the upper grip to the force transducer on the crosshead using the appropriate stud, shims, spacer, or spiral washers. Note
Series 647 Hydraulic Wedge Grips
Ensure that the force transducer is properly aligned (see your load unit manual).
A.
Thread the stud into the upper grip. The connector stud should should turn freely. If any resistance is encountered, disassemble and correct the problem before proceeding.
B.
Place a wooden spacer (a wood block or piece of plywood) on top of the lower grip. The wooden spacer should be large enough to cover the diameter of the grip.
C.
Insert the eyebolts into the threaded holes provided on the grip chamber.
Installation
59
WARNING
The upper grips are very top heavy and will have a tendency to tip over when lifted by the eyebolts. Dropped grips can cause injury to personnel and damage to equipment. Never attempt to control the grip by holding onto the eyebolts.Use the connector stud to help control the grip balance.
Note
The upper grip might need help to balance it on the wooden spacer on the lower grip.
D. Carefully position the grip on top of the wooden spacer on the lower grip. You might need to insert eyebolts into the threaded holes on the grip chamber. Attach a lifting device to the eyebolts and position the grip on top of the lower grip. E.
With the connector stud is facing up. Add any required shims, spacers, or spiral washers to the stud.
F.
Turn on hydraulic pressure and slowly lower the crosshead until the stud on the upper grip just makes contact with the extension rod connected to the force transducer. Reposition the grip as necessary for proper thread alignment.
G. Slowly screw the grip into the force transducer until it is snug. 5. Align the grip wedge openings. Go to “Aligning the Wedge Openings” on page 62 and check the alignment between the upper and lower grips. Align the lower grip as necessary for the desired hose connection and wedge opening orientation. If the actuator rod cannot be rotated, remove the lower grip and install one or more shim washers between the spiral washers and the lower element of the force train. Reinstall the grip. Align the upper grip wedge opening with the lower grip wedge opening. If proper alignment is not possible, remove the upper grip and install one or more shim washers between the spiral washers and the upper element of the force train. Reinstall the grip. 6. Connect the hydraulics. Typically, the shorter set of hard-line tubing is attached to the extension rod connected to the fixed end of the force train (the crosshead); the longer set is attached to the extension rod connected to the moving end (the actuator rod). Note
60
Installation
The Model 647.02 and 647.10 Hydraulic Wedge Grips require hydraulic pressure of 21 MPa (3000 psi). These grips can use the hydraulic power from the load unit or from a Model 685.22 Hydraulic Grip Supply.
Series 647 Hydraulic Wedge Grips
Note
The Model 647.25/.50/.100 Hydraulic Wedge Grip requires hydraulic pressure of 69 MPa (10000 psi). This grip must be connected to a Model 685.10 or 685.60 Hydraulic Grip Supply.
A.
Loosely attach the hydraulic hard-line tubing to the extension rods using the clamps provided.
B.
Turn the hydraulic pressure off. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving.
C.
Adjust the position of the hard-line tubing to allow the fittings to mate with the grip pressure and release ports.
D. Make connections between the pressure (labeled “P”) and release (labeled “R”) fittings on the upper extension rod and the pressure and release outlets for the upper grip on the hydraulic grip supply. E.
Make connections between the pressure (labeled “P”) and release (labeled “R”) fittings on the upper extension rod and the pressure and release outlets for the upper grip on the hydraulic grip supply.
F.
Tighten the hard-line tubing clamps to secure the tubing to the extension rods.
7. Install the cooling water lines. A.
Mount the cooling water valve clamp to a load unit column.
B.
Connect the cooling water lines to the extension rods as shown in the figure “Extension Rod Installation Components” on page 56 and between the extension rods and the cooling water valve/ drain.
C.
Connect a cooling water line between the upper and lower extension rods.
8. Tighten the grips. Go to “Preloading the Spiral Washers” on page 63 to preload all of the connector studs. Return to this procedure when done. 9. Install the wedges. Go to “Changing Wedges” on page 70 for the procedure to install wedges into the grips. This completes the extension rods installation.
Series 647 Hydraulic Wedge Grips
Installation
61
Aligning the Wedge Openings Once the grips are lightly tightened, check the alignment between the upper and lower grips; the wedge openings should be in the same plane. If the wedge openings are out of alignment, adjust the lower grip first, and then align the upper grip to the lower grip. The grips can be aligned several ways: •
Spiral washers
•
Shim washers
•
It might be possible to rotate the actuator rod to achieve the desired orientation.
Spiral washers can offer up to 30° of rotation. They are also used to preload the connector studs to prevent backlash. Spiral washers are installed between each grip and the mating member of the force train. They are used to preload the connector stud. When placing the spiral washers on the connector stud, rotate the washers until they are fully closed; this is the minimum thickness for the spiral washers. Then refer to “Preloading the Spiral Washers” on page 63. Shim washers are used to help align the upper and lower grips. Each shim kit includes washers of different thicknesses. A combination of the shims can change the rotation of the grip with reference to the point at which the grip is tightened into position. Shim washers are not necessary on the actuator side of the force train if the actuator can be rotated.
Grip Rotations and Shim Part Number Kit Part Number
1/16 Turn (22.5°)
1/8 Turn (45°)
1/4 Turn (90°)
1/2 Turn (180°)
1 Turn (360°)
521050-01
443665-18
443665-13
443665-17
443665-16
443665-14
521050-02
443665-18
443665-13
443665-17
443665-16
443665-18
521050-03
443665-21
443665-07
443665-20
443665-19
443665-03
521050-04
443665-21
443665-07
443665-20
443665-19
443665-21
521050-05
443665-25
443665-24
443665-24*
443665-22
443665-25
521050-06
443665-25
443665-24
443665-23
443665-23*
443665-25
521050-07
443665-02
443665-02*
443665-26
443665-26*
443665-27
521050-08
443665-27
443665-27*
443665-26
443665-26*
443665-27
521050-09
443665-29
443665-15
443665-28
443665-28*
443665-29*
521050-10
443665-29
443665-15
443665-28
443665-28*
443665-29
* Indicates that two shims are required to achieve the rotation.
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Installation
Series 647 Hydraulic Wedge Grips
Preloading the Spiral Washers The connector studs must be preloaded to prevent backlash. Preloading the connector studs requires that a full tensile load be applied to a specimen mounted in the grips. Therefore, it is assumed that the system hydraulics and the hydraulic grip supply are operational.
Required equipment
Multiple fixtures with different ratings
Procedure
The procedure requires that the spiral washers be installed on each connector stud in the force train. You will also need two spanner wrenches. Sometimes you might have multiple fixtures in the force train that have different force ratings. When installing the fixtures pretensioned with spiral washers, install the fixtures with the lowest force rating first. Then install any other fixtures from the lowest to the highest force rating. 1. Select force control at the system controller. 2. Turn on the system hydraulic pressure. 3. Select a dummy specimen that will withstand a tensile force 10 to 20% greater than the maximum force to be applied during the test. 4. Adjust the output pressure of the hydraulic grip supply to the level determined in “Determining the Gripping Pressure” on page 66. 5. Install the dummy specimen in the grips according to the steps provided in “Installing a Specimen” on page 74.
WARNING
The next step can apply a force greater than the force train capacity. Exceeding the tensile load capacity of any element in the force train can cause personal injury or equipment damage. It is necessary to temporarily exceed the tensile load capacity to achieve the requirements of Step 6 in this procedure. This is accomplished by increasing the output pressure of the HPU.
6. Apply a static tensile force 10 to 20% higher than the maximum force to be applied during testing.
CAUTION
If the spiral washers are not sufficiently tightened, the connector stud can break when subjected to cyclic loads. Improper preloading of the connector stud can cause eventual fatigue resulting in connector stud breakage. Sufficiently tighten the spiral washers as described in Step 7.
Series 647 Hydraulic Wedge Grips
Installation
63
7. Using spanner wrenches, rotate the two halves of the spiral washers in opposite directions to tighten them. The opening between the washers must not exceed an arc of 30° from the closed position. If more than a 30° arc is created, remove the tensile load from the specimen. Remove the specimen (see “Removing a Specimen” on page 77) and tighten the grips on the mounting studs, taking care not to misalign the wedge openings. Repeat Step 5 through Step 7 of this procedure. 8. Reduce tensile force to zero and remove the specimen. 9. Remove system hydraulic pressure. Ensure that system hydraulic pressure has been reduced to zero before proceeding. To do this, turn off the hydraulic power unit and exercise the actuator until it stops moving. Decrease Thickness
Increase Thickness Connector Stud Connector Stud
Medium Thickness
30° (Do not exceed.)
Connector Stud and Spiral Washers
64
Installation
Series 647 Hydraulic Wedge Grips
Operation This section describes how to use the grips.
Contents
Determining the Gripping Pressure Changing Wedges
70
Installing a Specimen Removing a Specimen
Basic operation
Grip controls
66
74 77
Operation of the hydraulic wedge grips consists of the following: •
Determining the minimum required specimen gripping pressure to accommodate a specific specimen and testing application
•
Selecting the appropriate wedges
•
Loading a specimen into the grips
The grip controls are located on the front panel of a load unit or on the front panel of an external hydraulic grip supply.
Hydraulic Controls 647 Hydraulic Wedge Grip
647 Hydraulic Wedge Grip
m 685.10 Hydraulic
Grip Supply
Crosshead Lift / Lock Control Emergency Stop
Hydraulic Grip Control Pressure
1
Rate
2
3
Load Unit
Hydraulic Grip Supply
Adjustment procedures for the hydraulic grip are supplied either in the load unit product manual or in the hydraulic grip supply product manual.
Series 647 Hydraulic Wedge Grips
Operation
65
Determining the Gripping Pressure The output pressure of the hydraulic grip supply determines the gripping force applied to the specimen by the wedges. The optimum gripping force is great enough to securely grip the specimen, yet low enough to minimize specimen deformation or prevent specimen slippage during the test.
WARNING
Improper grip pressure can damage the grips. Insufficient grip pressure can result in specimen slippage or wedge movement which can damage the grips. Using a grip pressure that exceeds the pressure rating of the grip can result in damage to the grips. The minimum pressure level, calculated in the following procedures, ensures that the wedges will be properly seated in the wedge chamber to prevent any movement of the wedges within the chamber when a full axial or load is applied to the specimen.
Definition of terms
This section defines the parameters used in the gripping pressure formulas. The figure “Gripping Principles” on page 67 illustrates some of the parameters. A
= Area of the grip piston (cm2 or in2) Model
A
647.02
16.38 cm2
2.54 in2
647.10
66.45 cm2
10.30 in2
647.25
50.58 cm2
7.84 in2
647.50
80.75 cm2
12.51 in2
647.100
173.96 cm2
26.95 in2
D
= Diameter of the round specimen (mm or in) (see the “Specifications” on page 13)
Fc
= Lateral clamping force of the wedge on the specimen (kN or lb)
fc-w = Frictional force between the grip chamber and the wedge fw-s = Frictional force between the wedge and the specimen fT
= Frictional forces reacting the torque
L
= Maximum axial load applied to the specimen (kN or lb)
Nc-w = Normal forces between the grip chamber and the wedge Nw-s = Normal forces between the wedge and the specimen
66
Operation
Series 647 Hydraulic Wedge Grips
P
= Grip supply pressure (MPa or psi)
T
= Maximum Torque applied to the specimen (N•m or lbf-in)
ts
= Thickness of the flat specimen (in or mm) (see the “Specifications” on page 13)
µc-w = Static coefficient of friction between the grip chamber and the wedge µw-s = Static coefficient of friction between the wedge and the specimen Ws
= Width of the flat specimen (mm or in) (see the “Specifications” on page 13) L T
D Fc
Nc-w fc-w = mc-wNc-w
Fc
fw-s = mw-sFc
Nc-w
fw-s = mw-sFc
PA 2
fc-w = mc-wNc-w
PA 2
Nw-s
Nw-s
fT fT
fT
T fT
Nw-s
Nw-s
Wedges for Round Specimens
ts Fc
Ws
Fc T
Wedges for Flat Specimens
Gripping Principles
Series 647 Hydraulic Wedge Grips
Operation
67
Axial for round specimens (and axial/torsional for flat specimens)
The following procedure determines the minimum gripping pressure for axial testing of round specimens and axial/torsional testing for flat specimens. 1. Determine the maximum axial load to be applied to the specimen for the test. 2. Calculate the minimum grip supply pressure according to the formula: For fatigue testing:
For monotonic testing:
× L ( lbf ) P ( psi ) = A ( in )
× L ( lbf ) P ( psi ) = A ( in )
× L ( kN ) P ( MPa ) = A ( cm )
× L ( kN ) P ( MPa ) = A ( cm )
3. If desired, determine the actual clamping force (Fc) applied to the specimen by using the following formula: F c = PA To derive the above equation, the static coefficient of friction (µ) between the grip and wedge was assumed to be 0.06 for lubricated steel on steel. If a different coefficient of friction is needed use the following formula, substituting your own value for µ. PA FRV – µ VLQ F c = VLQ – µ FRV
68
Operation
Series 647 Hydraulic Wedge Grips
Axial-torsional for round specimens only
The following procedure determines the minimum gripping pressure for axial/torsional testing of round specimens. Note
The following figure shows the amount of torque the grips can provide is reduced at higher axial forces. See “Force and Torque Capacities” on page 14 for more information.
1. Determine the maximum torque to be applied to the specimen for the test. 2. Calculate the minimum grip supply pressure according to the formula:
T ( lb ⋅ in ) L ( lb ) + P c ( psi ) = A ( in ) D ( in )
T ( N ⋅ m ) L ( kN ) + P c ( MPa ) = A ( cm ) D ( mm )
3. If desired, determine the actual clamping force (Fc) applied to the specimen by using the following formula: F c = PA To derive the above equation, the static coefficient of friction (µc-w) between the grip and wedge was assumed to be 0.06 for lubricated steel on steel. If a different coefficient of friction is needed use the following formula, substituting your own value for µc-w. PA FRV – c – w VLQ F c = c – w VLQ – µ FRV
Series 647 Hydraulic Wedge Grips
Operation
69
Changing Wedges Standard and optional wedges are available for the grips. The standard wedges include: •
narrow flat wedges for flat specimens,
•
round wedges for specific diameter round specimens, and
•
Vee-notched wedges for round specimens in general
The optional wedges include wide wedges for flat, full width specimens. See “Specifications” on page 13 for a listing of all available wedges.
CAUTION
The wedges can rust. Over time, rust can damage the wedges. Use cloth or latex gloves when handling the wedges. Also coat the wedges with LPS (a rust preventative oil) and place them in their original packing material for storage.
Required equipment
70
Operation
•
A utility hook (provided in the tool kit supplied with the Grip)
•
Replacement extension springs, if necessary
•
Two, 50 cm (20 in) length of wire cable, for wide wedges
•
Lubricant (see “Temperature ranges” on page 13 for information about lubricants and temperature ranges).
Series 647 Hydraulic Wedge Grips
Changing Standard Wedges Perform the following procedure to replace one type of narrow wedge with the other, or a narrow wedge with a 38.1 mm (1.5 in) wide wedge. Note
Each wedge is labeled with the wedge part number and manufacturing date code. Ensure that replacement wedges are a matched set before attempting to install the wedges into the grip.
1. Remove any specimen installed in the grips. Leave both grip controls in the release position. Position the actuator or crosshead as necessary for convenient access to the grip wedges. Remove system hydraulic pressure and grip supply pressure. 2. Using the utility packing hook, disconnect both springs from the spring posts on the corresponding wedge. It is not necessary to remove the springs from the spring anchors. 3. Inspect the springs and replace them, if necessary. 4. Remove the wedge by sliding it towards the center of the grip and then lifting it out of the grip. 5. Repeat Steps 2 and 3 for the remaining wedges. Review the Caution on page 70. 6. Apply a thin coat of lubricant to the edges of the wedge which contact the chamber and piston; see “Temperature ranges” on page 13 for information about the temperature ranges and restrictions. 7. Place the wedge into the center of the grip and then slide it towards the chamber. 8. Using the utility packing hook, connect the springs from the spring anchor on the grip piston to the spring post on the corresponding wedge. 9. Repeat Steps 6 and 7 for the remaining wedges.
Series 647 Hydraulic Wedge Grips
Operation
71
Changing Wide Wedges Perform the following procedure to replace a narrow wedge set with a wide wedge set, or a wide wedge set with another wide wedge set. Each wedge is labeled with the wedge part number and manufacturing date code. Ensure that replacement wedges are a matched set (four wedges) before attempting to install the wedges into the grip. Chamber
Wedges
Cap Screw
Wire Cables Spring
Spring Anchor
Piston
Wedge
1. Remove any specimen installed in the grips. Leave both grip controls in the release position. Position the actuator or crosshead as necessary for convenient access to the Grip wedges. Remove system hydraulic pressure and grip supply pressure. 2. Remove the specimen guide from flat wedges. 3. Remove the wedge set from the grip as follows: A.
Using the utility packing hook, disconnect both springs from the spring posts on the corresponding wedge.
B.
It is not necessary to remove the springs from the spring anchors. However, inspect the springs and replace them, if necessary
C.
Remove the wedge by sliding it towards the center of the grip and then lifting it out of the grip.
D. Repeat Step A through Step C for the remaining wedges. Review the Caution on page 70. 4. Apply a thin coat of Molykote G-n lubricant to the edges of the replacement wedge which contact the chamber and piston. 5. Thread a 50 cm (20 in) length of wire cable (two required) through the eye on the free end of each spring. 6. Thread the free ends of each cable loop through the respective spring holes in the wedge.
72
Operation
Series 647 Hydraulic Wedge Grips
7. While holding the ends of both cables, guide the wedge into the grip such that the springs will enter the spring holes. 8. With the wedge seated in the grip, pull on one pair of wire cable ends. Pull the spring tight until a cap screw can be inserted through the spring eye. Tighten the cap screw. 9. Repeat Step 8 for the remaining spring. 10. Repeat Steps 4 through 9 for the other wedges. 11. For flat wedges, install the specimen guide.
Series 647 Hydraulic Wedge Grips
Operation
73
Installing a Specimen This procedure describes how to install a specimen into the grips.
WARNING
The area between the upper and lower grips is in a crush zone. Unexpected actuator movement in the crush zone can result in injury to personnel and damage the specimen. Use extreme care while installing a specimen.
Before installing the specimen
1. Before installing the specimen, install the appropriate set of wedges for the specimen to be tested. Use the installation instructions in this chapter for the type of wedge you are using. 2. Make sure that the specimen shank is within the tolerances listed for the type of wedge you are using. Size and tolerance for various types of wedges are listed in the “Introduction” chapter. Make sure that the specimen shank is within the required tolerance. Failure to comply with specimen tolerances can cause wedges to fail. Make sure that every specimen is within the tolerance listed for the type of wedge and type of specimen. Tolerances are listed for various wedge types in the “Introduction” chapter.
Procedure
Perform the following procedure to install a specimen into a set of hydraulic grips. 1. Adjust the grip supply pressure to the minimum level as determined in “Determining the Gripping Pressure” on page 66 (see your load unit or hydraulic grip supply product information manual). 2. Select force control and the most sensitive range available at the controller. Note
Displacement control is not recommended for specimen installation. If you must use displacement control, use extreme care not to apply specimen-damaging forces when adjusting the grip position.
3. Release the upper and lower grips using the hydraulic grip supply controls. Note
When using vee-notched or round wedges (for use with round specimens) skip to Step 6.
4. If you are working with flat wedges, loosen the cap screws securing the specimen guides on the wedges. Adjust the specimen guides so as to allow the specimen to be centered in the grip. Tighten the socket head cap screws.
74
Operation
Series 647 Hydraulic Wedge Grips
5. Apply full system hydraulic pressure according to applicable system procedures. Use extreme care not to cause rapid actuator movement when performing the following steps.
CAUTION
The contact area between the wedge face and specimen should be as large as possible. A small contact area between the wedge face and specimen can cause premature wear to the wedge face surface. MTS recommends that specimens should be machined to provide the largest possible surface contact area between the wedge face and the specimen
Wedge face
Contact area (H x W)
H H W
W Bottom gap specification (3-6 mm)
CAUTION
Large contact area recommended
Small contact area can cause premature wear
Improper specimen installation can damage the wedges. To prevent damage to the grips and possible wedge failure, install the specimen in the wedges precisely as specified in the following steps.
6. Place the specimen in the lower grip allowing a space of at least 3 mm (0.12 in) but not greater than 6 mm (0.25 in) between the bottom of the specimen and the bottom inner edges of the lower grip wedges. Lock the lower grip. 7. Extend the actuator until the specimen is positioned in the upper grip allowing a space of at least 3 mm (0.12 in) but not greater than 6 mm (0.25 in) between the top of the specimen and the inner top edges of the wedges. Lock the upper grip.
Series 647 Hydraulic Wedge Grips
Operation
75
CAUTION
Specimen slippage during the test can damage the grips. Specimen slippage typically occurs when: •
Insufficient grip pressure is used to securely grip the specimen
•
Wedges with worn (rounded or flattened) serrations are used
•
A specimen with a hardness of Rc 52 or greater is being tested
In most instances, when testing specimens with a hardness less than Rc 52, increase hydraulic grip supply pressure to prevent slippage. Do not exceed the maximum pressure rating of the grip. However, increasing the pressure setting to hold round specimens can reduce the life of the vee-notched wedges.
8. Adjust the grip pressure to the maximum level as determined in “Determining the Gripping Pressure” on page 66. 9. If specimen slippage occurs which exceeds the specifications in Step 7 and Step 8, reinstall the specimen and increase the grip pressure. Note the caution above. If a series of similar specimens will be used and specimen dimensions permit side insertion, it is not necessary to repeat this entire procedure for each specimen. When loading a similar specimen, release the upper and lower grips and remove the old specimen. Then insert the new specimen as described in Step 6 and clamp the specimen.
76
Operation
Series 647 Hydraulic Wedge Grips
Removing a Specimen This procedure describes how to remove a specimen from the grips.
WARNING
The environmental chamber and the grips can be subjected to extreme temperatures during the test. Opening the door after a test will vent the hot or cold air from the chamber. Touching chamber or grip parts before they have been allowed to reach a tolerable handling temperature or without adequate protective clothing or tools can result in serious freeze or burn injury. Do not stand or put unprotected hands in the path of the venting heated air while opening the door. Open the door only enough to allow the heated air to escape. Note that the thermal mass of the gripping end and specimen inside the chamber will continue to heat the air escaping from the chamber. Allow the specimen to reach a tolerable temperature or use protective clothing or appropriate tools before attempting to remove it. The length of time required will be dictated by the size of the grip and specimen, the testing temperature, and the length of time at that temperature.
Prerequisite
After high-temperature testing, open the door slightly to allow the heated air to escape. Do not stand or put unprotected hands in the path of the escaping air when opening the door. Wait for the air to cool. Open the door the rest of the way. Allow the specimen to reach a tolerable temperature before attempting to remove it, or use appropriate tools, such as tongs, to remove the specimen.
WARNING
Heavy or fractured specimens can fall from the grips when released. Injury to personnel or damage to the test equipment can result. Take adequate precautions to support heavy or fractured specimens.
Procedure
1. Turn on system hydraulic pressure and hydraulic grip supply pressure according to applicable system procedures. 2. Release the upper and lower grips. 3. Remove the specimen. If the specimen is not fractured, it might be necessary to retract the actuator.
Series 647 Hydraulic Wedge Grips
Operation
77
78
Operation
Series 647 Hydraulic Wedge Grips
Maintenance After approximately 100 lock and release cycles, remove the wedges from the hydraulic wedge grips and apply an antiseizing compound to the edges of the wedge which contact the wedge chamber and grip piston. Perform the following steps to maintain the wedges.
Procedure
1. Remove the wedges from the grip chamber using the procedure in “Changing Wedges” on page 70. 2. Apply a thin layer of lubricant to the edges of the wedge which contact the wedge chamber and grip piston; see the “Temperature ranges” on page 13 for the recommended lubricant. The edges of the wedge which contact the chamber and piston and the cap screws securing the specimen guides on the wedges should be lubricated after approximately 25 hours of operation or after the test. 3. Repeat Steps 1 and 2 for the other grip. 4. Replace each wedge into the grip using the procedure in “Changing Wedges” on page 70.
Series 647 Hydraulic Wedge Grips
Maintenance
79
80
Maintenance
Series 647 Hydraulic Wedge Grips
Service This section describes how to replace the seals in the Series 647 Hydraulic Wedge Grips. If additional service is required, call your local MTS service representative. Important
This section describes service procedures that should be performed by a person who has experience servicing servohydraulic equipment. The procedures in this section require the grips to be disassembled beyond what is needed for operation or maintenance. We assume that you are familiar with all operating aspects of your system controller (electronic and software controls) and you are familiar with the hardware components of your system.
The seals in the grip should be replaced if there is excessive oil leaking from the grips when the grips are pressurized.
Contents
Axial and Axial-Torsional Seal Replacement All Temperature Seal Replacement
Required equipment
83
86
In addition to the equipment to remove the grips, you will need the following: •
A replacement seal kit
•
A rubber mallet
•
A standard hose clamp slightly larger than the excluder ring
•
A torque wrench
Series 647 Hydraulic Wedge Grips
Service
81
Tool kit
A tool kit is provided with each set of grips. It contains a set of spare extension springs for securing the wedges in the grip, a utility hook, the tools required to disassemble the grip, and eyebolts and a swivel eye for installing and removing the grips.
Seal kits
Each seal kit contains enough seals to service both the upper and lower grip. The kits include a quantity of Molykote G-n paste and appropriate lubricants for the rated temperature.
Model
-40° to 120°C (-40° to 250°F)*
-40° to 177°C (-40° to 350°F)†
-130° to 315°C (-200° to 600°F)‡
-130° to 540°C (-200° to 1000°F)§
647.02A|
047-810-701
047-810-702
046-953-701
046-953-702
647.02B|
056-143-501
056-143-502
not available
not available
647.10
047-810-901
048-910-902
046-953-801
046-953-802
647.25
047-810-801
047-810-802
046-953-901
046-953-902
647.50
047-811-001
047-811-002
not available
not available
647.100
054-279-201
not available
not available
not available
* The 120ºC (250ºF) specification requires a dedicated hydraulic grip supply. Grips using the system HPU and load unit grip controls are limited to 66ºC (150ºF). † Grips used in this temperature range must use a dedicated hydraulic grip supply such as the MTS Model 685.60 Hydraulic Grip Supply and appropriate hydraulic fluid. ‡ Grips used in this temperature range must have a -3X model identifier (for example, 647.10A-31) and dedicated hydraulic grip supply; see footnote † § Grips used in this temperature range must have a -5X model identifier (for example, 647.25A-52) and dedicated hydraulic grip supply; see footnote †. | 647.02A is the steel grip. 647-02B is the aluminium grip.
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Service
Series 647 Hydraulic Wedge Grips
Axial and Axial-Torsional Seal Replacement Use this procedure to replace seals in a Series 647 Hydraulic Wedge Grip. Note
Procedure
Do not use this procedure to replace seals in MTS Model 647.10A-11 or Model 647.25A-22 Hydraulic Wedge Grips. If seal replacement is needed for either of these models please contact your local MTS Field Service Engineer.
1. Remove the grips from the load unit. The grips are removed in the reverse order in which they were installed. Go to “Installation” on page 31 and perform the appropriate installation procedure in reverse order. Return to this procedure when the grips are removed from the load unit. 2. Disassemble the grip. A.
Place the grip on the work surface with the wedge opening down.
B.
Remove the six socket head cap screws securing the end cap to the wedge chamber.
C.
Slide the end cap off the piston.
D. Separate the piston from the chamber. If necessary, lay the unit on its side, place a piece of wood or soft metal (such as aluminum) between the wedge slot in the piston, and use a rubber mallet to force the piston out. 3. Replace the seals.
Wedges Chamber
Piston
End Cap
Cap Screws
The following figure shows the seal locations for two styles of grips (both are 647 grips). A.
Remove the excluder, O-rings, and retainers on the grip piston, wedge chamber, and end cap. Remove the old excluder by cutting it. Remove the old O-rings and retaining rings using the utility packing hook. Be careful not to nick or scratch the edges of the seal grooves.
Note
Series 647 Hydraulic Wedge Grips
On the Model 647.02 Grip the O-ring between the end cap and the chamber is located inside the chamber, not on the end cap.
Service
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B.
Install the O-rings and retainers. Lubricate the new parts with clean hydraulic fluid as you replace them. Install the O-ring and retaining ring sets in the end cap, piston, and if needed, in the chamber.
Note
When replacing O-ring and retaining ring sets, install the retaining ring(s) first and then install the O-ring.
O-rings are shown in black Retainers are shown in gray.
Seal Locations C.
Install the excluder O-ring and then the excluder. If the excluder will not stretch over the end of the piston, use a blow dryer or heated hydraulic fluid to warm it to approximately 52°C (125°F) or until it is elastic enough to stretch over the piston. After installing the excluder, use a hose clamp and a piece of thin shim stock (about 0.0025 mm; 0.0001 in) to compress the excluder to its original shape. Place the shim stock between the hose clamp and excluder to protect the excluder from being deformed by the holes in the hose clamp. Tighten the hose clamp enough to compress the excluder. Leave it this way for about an hour, and then remove the hose clamp and shim stock.
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4. Assemble the axial grip. A.
Turn the chamber so that the wedge opening is resting on the work surface.
B.
Insert the piston into the chamber. Ensure that the wedge slot on the piston is properly oriented with the wedge opening in the chamber.
C.
Replace the end cap.
D. Lubricate the socket-head cap screws and insert them into the end cap; see the “Temperature ranges” on page 13 for the recommended lubricant. Torque the end cap screws to the specification listed in the following table. End Cap Torque Requirements
E.
Series 647 Hydraulic Wedge Grips
Model
Torque
647.02
0.396 N·m (9.4 lb·ft)
647.10
1.48 N·m (35 lb·ft)
647.25
3.37 N·m (80 lb·ft)
647.50
6.74 N·m (160 lb·ft)
647.100
32.03 N·m (760 lb·ft)
Install the grips onto the load unit by performing the appropriate installation procedure. See “Installation” on page 31.
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All Temperature Seal Replacement Perform the following procedure to replace the seals in a Series 647 Hydraulic Wedge Grip. 1. Remove the grips from the load unit. The grips are removed in the reverse order in which they were installed. Go to “Installation” on page 31 and perform the appropriate installation procedure in reverse order. Return to this procedure when the grips are removed from the load unit. 2. Disassemble the grip. A.
Place the grip on the work surface.
B.
Using strap wrenches unscrew the wedge chamber from the piston extension.
C.
Remove the socket head bolt securing the piston extension to the hydraulic chamber.
D. Unscrew the cylinder from the hydraulic chamber. E.
Separate the piston from the chamber.
3. Disassemble the hydraulic chamber.
Hydraulic Chamber
Cylinder
Piston Extension
Wedge Chamber
A.
Using a hex wrench, remove the eight socket head bolts securing the cylinder to the end cap.
B.
Remove the end cap.
C.
Separate the piston from the cylinder. It might be necessary to use a rubber mallet.
4. Replace the seals. A.
Remove the O-rings, retainer rings, and wiper ring from the cylinder, piston, and end cap. Be careful not to nick or scratch the edges of the seal grooves.
B.
Install the replacement O-rings, retainer rings, and wiper ring. Lubricate the new parts with clean hydraulic fluid as you replace them.
Note
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When replacing O-ring and retaining ring sets, install the retaining ring(s) first and then install the O-ring.
Series 647 Hydraulic Wedge Grips
Socket Head Bolts (8) Retainer Ring O-ring
Cylinder Retainer Ring O-ring Retainer Ring
Piston
O-ring O-ring Retainer Ring Wiper Ring End Cap
Seal Locations 5. Assemble the hydraulic chamber. A.
Insert the piston into the cylinder.
B.
Slide the end cap over the end of the piston.
C.
Lubricate the socket-head cap screws and insert them into the cylinder. Torque the end cap screws to the specification listed in the following table. End Cap Torque Requirements
Series 647 Hydraulic Wedge Grips
Model
Torque
647.02
3.9 N·m (5.3 lb·ft)
647.10
34 N·m (47 lb·ft)
647.25
84 N·m (110 lb·ft)
647.50
217 N·m (160 lb·ft)
647.100
1030 N·m (760 lb·ft)
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3
5
1
7
8
2 6
4
6. Install the grips. Remount the grips onto the load unit by performing the appropriate installation procedure. Depending on the procedure, you might need to reassemble the grips. See “Installation” on page 31.
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