Instron 2712 Series Manual

2712 Series Pneumatic Side-Action Grips
Operator’s Guide M10-16235-EN Revision E
The difference is measurable
®

Electromagnetic Compatibility
Where applicable, this equipment is designed to comply with International Electromagnetic
Compatibility (EMC) standards.
To ensure reproduction of this EMC performance, connect this equipment to a low impedance
ground connection. Typical suitable connections are a ground spike or the steel frame of a
building.
Proprietary Rights Notice
This document and the information that it contains are the property of Illinois Tool Works Inc.
(ITW). Rights to duplicate or otherwise copy this document and rights to disclose the document
and the information that it contains to others and the right to use the information contained
therein may be acquired only by written permission signed by a duly authorized officer of ITW.
Trademarks
Instron®is a registered trademark of Illinois Tool Works Inc. (ITW). Other names, logos, icons and
marks identifying Instron products and services referenced herein are trademarks of ITW and
may not be used without the prior written permission of ITW.
Other product and company names listed are trademarks or trade names of their respective
companies.
Original Instructions
Copyright © 2009 Illinois Tool Works Inc. All rights reserved. All of the specifications shown in
this document are subject to change without notice.
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Instron
825 University Avenue
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United States of America
European Headquarters
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3
Preliminary Pages
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General Safety Precautions
Materials testing systems are potentially hazardous.
Materials testing involves inherent hazards from high forces, rapid motions, and
stored energy. You must be aware of all moving and operating components in
the testing system that are potentially hazardous, particularly force actuators or
a moving crosshead.
Carefully read all relevant manuals and observe all Warnings and Cautions. The
term Warning is used where a hazard may lead to injury or death. The term
Caution is used where a hazard may lead to damage to equipment or to loss of
data.
Instron products, to the best of its knowledge, comply with various national and
international safety standards, in as much as they apply to materials and
structural testing. We certify that our products comply with all relevant EU
directives (CE mark).
Because of the wide range of applications with which our instruments are used,
and over which we have no control, additional protection devices and operating
procedures may be necessary due to specific accident prevention regulations,
safety regulations, further EEA directives or locally valid regulations. The extent
of our delivery regarding protective devices is defined in your initial sales
quotation. We are thus free of liability in this respect.
At your request, we will gladly provide advice and quotations for additional
safety devices such as protective shielding, warning signs or methods of
restricting access to the equipment.
The following pages detail various general warnings that you must heed at all
times while using materials testing equipment. You will find more specific
Warnings and Cautions in the text whenever a potential hazard exists.
Your best safety precautions are to gain a thorough understanding of the
equipment by reading your instruction manuals and to always use good
judgement.
It is our strong recommendation that you should carry out your own product
safety risk assessment.

Preliminary Pages
4M10-16235-EN
Warnings
Hazard - Press the Emergency Stop button whenever you consider that an
unsafe condition exists.
The Emergency Stop button removes hydraulic power or electrical drive from the
testing system and brings the hazardous elements of the system to a stop as
quickly as possible. It does not isolate the system from electrical power, other
means are provided to disconnect the electrical supply. Whenever you consider
that safety may be compromised, stop the test using the Emergency Stop
button. Investigate and resolve the situation that caused the use of the
Emergency Stop button before you reset it.
Flying Debris Hazard - Make sure that test specimens are installed correctly
in grips or fixtures in order to eliminate stresses that can cause breakage of
grip jaws or fixture components.
Incorrect installation of test specimens creates stresses in grip jaws or fixture
components that can result in breakage of these components. The high
energies involved can cause the broken parts to be projected forcefully some
distance from the test area. Install specimens in the center of the grip jaws in
line with the load path. Insert specimens into the jaws by at least the amount
recommended in your grip documentation. This amount can vary between 66%
to 100% insertion depth; refer to supplied instructions for your specific grips.
Use any centering and alignment devices provided.
Hazard - Protect electrical cables from damage and inadvertent
disconnection.
The loss of controlling and feedback signals that can result from a disconnected
or damaged cable causes an open loop condition that may drive the actuator or
crosshead rapidly to its extremes of motion. Protect all electrical cables,
particularly transducer cables, from damage. Never route cables across the
floor without protection, nor suspend cables overhead under excessive strain.
Use padding to avoid chafing where cables are routed around corners or
through wall openings.

5
Preliminary Pages
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High/Low Temperature Hazard - Wear protective clothing when handling
equipment at extremes of temperature.
Materials testing is often carried out at non-ambient temperatures using ovens,
furnaces or cryogenic chambers. Extreme temperature means an operating
temperature exceeding 60 °C (140 °F) or below 0 °C (32 °F). You must use
protective clothing, such as gloves, when handling equipment at these
temperatures. Display a warning notice concerning low or high temperature
operation whenever temperature control equipment is in use. You should note
that the hazard from extreme temperature can extend beyond the immediate
area of the test.
Crush Hazard - Take care when installing or removing a specimen,
assembly, structure, or load string component.
Installation or removal of a specimen, assembly, structure, or load string
component involves working inside the hazard area between the grips or
fixtures. When working in this area, ensure that other personnel cannot operate
any of the system controls. Keep clear of the jaws of a grip or fixture at all times.
Keep clear of the hazard area between the grips or fixtures during actuator or
crosshead movement. Ensure that all actuator or crosshead movements
necessary for installation or removal are slow and, where possible, at a low
force setting.
Hazard - Do not place a testing system off-line from computer control
without first ensuring that no actuator or crosshead movement will occur
upon transfer to manual control.
The actuator or crosshead will immediately respond to manual control settings
when the system is placed off-line from computer control. Before transferring to
manual control, make sure that the control settings are such that unexpected
actuator or crosshead movement cannot occur.
Robotic Motion Hazard - Keep clear of the operating envelope of a robotic
device unless the device is de-activated.
The robot in an automated testing system presents a hazard because its
movements are hard to predict. The robot can go instantly from a waiting state
to high speed operation in several axes of motion. During system operation,
keep away from the operating envelope of the robot. De-activate the robot
before entering the envelope for any purpose, such as reloading the specimen
magazine.
Warnings

Preliminary Pages
6M10-16235-EN
Hazard - Set the appropriate limits before performing loop tuning or running
waveforms or tests.
Operational limits are included within your testing system to suspend motion or
shut off the system when upper and/or lower bounds of actuator or crosshead
travel, or force or strain, are reached during testing. Correct setting of
operational limits by the operator, prior to testing, will reduce the risk of damage
to test article and system and associated hazard to the operator.
Electrical Hazard - Disconnect the electrical power supply before removing
the covers to electrical equipment.
Disconnect equipment from the electrical power supply before removing any
electrical safety covers or replacing fuses. Do not reconnect the power source
while the covers are removed. Refit covers as soon as possible.
Rotating Machinery Hazard - Disconnect power supplies before removing
the covers to rotating machinery.
Disconnect equipment from all power supplies before removing any cover which
gives access to rotating machinery. Do not reconnect any power supply while
the covers are removed unless you are specifically instructed to do so in the
manual. If the equipment needs to be operated to perform maintenance tasks
with the covers removed, ensure that all loose clothing, long hair, etc. is tied
back. Refit covers as soon as possible.
Hazard - Shut down the hydraulic power supply and discharge hydraulic
pressure before disconnection of any hydraulic fluid coupling.
Do not disconnect any hydraulic coupling without first shutting down the
hydraulic power supply and discharging stored pressure to zero. Tie down or
otherwise secure all pressurized hoses to prevent movement during system
operation and to prevent the hose from whipping about in the event of a
rupture.
Hazard - Shut off the supply of compressed gas and discharge residual gas
pressure before you disconnect any compressed gas coupling.
Do not release gas connections without first disconnecting the gas supply and
discharging any residual pressure to zero.
Warnings

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Preliminary Pages
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Explosion Hazard - Wear eye protection and use protective shields or
screens whenever any possibility exists of a hazard from the failure of a
specimen, assembly or structure under test.
Wear eye protection and use protective shields or screens whenever a risk of
injury to operators and observers exists from the failure of a test specimen,
assembly or structure, particularly where explosive disintegration may occur.
Due to the wide range of specimen materials, assemblies or structures that may
be tested, any hazard resulting from the failure of a test specimen, assembly or
structure is entirely the responsibility of the owner and the user of the
equipment.
Hazard - Ensure components of the load string are correctly pre-loaded to
minimize the risk of fatigue failure.
Dynamic systems, especially where load reversals through zero are occurring,
are at risk of fatigue cracks developing if components of the load string are not
correctly pre-loaded to one another. Apply the specified torque to all load string
fasteners and the correct setting to wedge washers or spiral washers. Visually
inspect highly stressed components such as grips and threaded adapters prior
to every fatigue test for signs of wear or fatigue damage.
Warnings

Preliminary Pages
8M10-16235-EN

9
Preliminary Pages
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Table of Contents
Chapter 1: Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Grip Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Chapter 2: Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Grip Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Grips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Air Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Grip Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Compatible Jaw Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Jaw Face Shields. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Specimen Alignment Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Chapter 3: Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Installing onto a Load Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Procedure - installing 250N, 1kN and 2kN grips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Procedure - installing 5kN and 10kN grips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Installing and Removing Jaw Faces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Install Jaw Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Remove Jaw Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Install Jaw Face Shields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Install the Specimen Alignment Device. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Adjust the Jaw Face Opening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Connecting Pneumatics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Grip Air Inlets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Adjusting the Air Inlet Flow Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Air Valve Toggle Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Install or remove air valve toggle switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Preliminary Pages
10 M10-16235-EN
Manual Foot Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Automatic Grip Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Preload the Load String . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Procedure to preload the load string: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Procedure to unload the load string: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Chapter 4: Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Preparing for Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Opening and Closing the Grips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Toggle Valve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Foot Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Automatic Grip Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Installing a Specimen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Checklist for installing a specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Procedure for installing a specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Removing a Specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Checklist for removing a specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Procedure for removing a specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Chapter 5: Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Lubrication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Jaw faces sticking and jaw holder not retracting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

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Chapter 1
Introduction
•Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
•Grip Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
•Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Description
Instron Series 2712 pneumatic action grips are designed for materials testing
applications where specimens are difficult to hold in conventional screw-action grips.
Pneumatic action grips allow rapid, easy loading of specimens from delicate films to
polymers and woven fabrics. The grips are available in the following capacities:
2712-052 grips can support loads up to 500N but some specimens may slip at loads
over 250N. We recommend the use of serrated jaw faces for expected loads higher than
250N.
Both jaw faces automatically adjust to different specimen thicknesses to ensure that
the line of tensile force remains concentric with the grip body. The grips can be equipped
with a variety of interchangeable jaw faces in various sizes and surface types. Refer to
Table 3 on page 21 to find compatible jaw faces for your specific model. Contact your
Instron sales representative for assistance with selecting jaw faces that are suitable for
your testing requirements.
These pneumatic action grips clamp the specimen through a dual lever arm, actuated by
air cylinders built into the grip body. The gripping force can be increased with air
Catalog number Capacity (kN)
2712-052 0.25
2712-041 1
2712-042 2
2712-045 5
2712-046 10

Chapter: Introduction
12 M10-16235-EN
pressure to accommodate materials that are often difficult to hold. This constant
gripping force is maintained on the specimen, and provides follow-up action to
compensate for any decay in the gripping force. The grips have an integral toggle air
valve to open and close the grips. You can also operate the grips using a separate
pneumatic foot switch.
Grip Components
Figure 1. Grip Components
Letter Description
AGripcoupling
BLocknut
C Quick connect coupling

13
Accessories
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Accessories
The following accessories are available. Refer to “Installation” for more details.
•Jaw face shields
•Specimen alignment device
•Pneumatic foot switch
•Automatic grip controller
DFlowcontrol
E Air switch
F Accessory mounting holes
Letter Description

Chapter: Introduction
14 M10-16235-EN

15
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Chapter 2
Specifications
•Grip Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
•Grip Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
•Compatible Jaw Faces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
•Jaw Face Shields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
•Specimen Alignment Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Grip Specifications
Grips
Table 1. Grip Specifications
2712-052 2712-041 2712-042 2712-045 2712-046
Load capacity
(kN)
0.25112510
Test Application Tensile
Mechanical
connection
(upper and lower)
Type Om
6 mm (0.25
in)
clevis pin
Type Om
6 mm (0.25
in)
clevis pin
Type Om
6 mm (0.25
in)
clevis pin)
Type Dm
13 mm (0.5
in)
clevis pin
Type Dm
13 mm (0.5
in)
clevis pin)
Maximum
specimen
thickness
Varies
according to
jaw face, refer
to Table 4 on
page 23
Varies according to jaw face, refer to Table 3 on page 21
Nominal
specimen
thickness (mm)2
5.82 13 20 26 26

Chapter: Specifications
16 M10-16235-EN
Air Supply
To ensure long term operation of the grips the air supply must be dry and filtered. To
ensure dry air you can install an in-line desiccant air dryer (not available from Instron) at
the compressor. Use of a local regulator and 5 μm filter assembly near the testing
system is also recommended.
Grip operating pressure range is 2.8 bar (40 psi) to 6.2 bar (90 psi). If the air pressure is
below the minimum recommended 2.8 bar (40 psi), gripping force will be diminished.
Figure 3 on page 18 and Figure 4 on page 19 illustrate this effect.
Gripping force at
90 psi (6 bar) air
pressure (mid-
stroke)
496 N
(112 lbf)
2.3 kN
(517 lbf)
5.0 kN
(1124 lbf)
12.6 kN
(2832 lbf)
23.9 kN
(5373 lbf)
Temperature
range
-20°C to +100°C
Weight (each grip) 0.35 kg
(0.78 lb)
2.5 kg (5.6 lb) 4.1 kg (9.1 lb) 6.8 kg (15.0
lb)
9.7 kg (21.4
lb)
Air supply
pressure range
2.8 bar (40 psi) to 6.2 bar (90 psi)
Air supply -
consumption3(SC
FM)
0.002 0.006 0.018 0.018 0.032
1. These grips can support loads up to 500N but some specimens may slip at loads over 250N. We recom-
mend the use of serrated jaw faces for expected loads higher than 250N.
2. This value assumes 51mm x 51 mm serrated jaw faces. Refer to Table 3 on page 21 for different faces.
3. SCFM is Standard Cubic Feet per Minute, assuming 1 gripping cycle per minute for the entire grip set.
This measurement assumes air pressure of 5.5 bar (80 psi).
Table 1. Grip Specifications (Continued)
2712-052 2712-041 2712-042 2712-045 2712-046

17
Grip Specifications
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Figure 2. Clamping force vs Air pressure for 250N grips

Chapter: Specifications
18 M10-16235-EN
Figure 3. Clamping force vs Air pressure for 1kN and 2kN grips

19
Grip Dimensions
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Figure 4. Clamping force vs Air pressure for 5kN and 10kN grips
Grip Dimensions
Table 2. Grip Dimensions - mm (in)
Dimension -
mm (in)
Label on
Figure 5 2712-052 2712-041 2712-042 2712-045 2712-046
Overall width A 68.8 (2.7) 126 (5.0) 152 (6.0) 199 (7.8) 208 (8.1)
Overall height B 130.4 (5.1) 184 (7.2) 194 (7.6) 251 (9.9) 255 (10.0)
Depthincluding
fittings
C 87.4 (3.4) 129 (5.1) 173 (6.8) 184 (7.2) 226 (8.9)
Piston outside
diameter
D 62.8 (2.5) 100 (3.9) 145 (5.7) 160 (6.3) 202 (8.0)
Body thickness E 15.6 (0.61) 31 (1.2) 31 (1.2) 42 (1.7) 54 (2.1)
Effective length F 122.4 (4.8) 176 (6.9) 186 (7.3) 236 (9.3) 239 (9.4)

Chapter: Specifications
20 M10-16235-EN
Figure 5. Grip Dimensions
Jaw center to
grip edge
G 7.96 (0.31) 16 (0.63) 16 (0.63) 19 (0.75) 19 (0.75)
Table 2. Grip Dimensions - mm (in) (Continued)
Dimension -
mm (in)
Label on
Figure 5 2712-052 2712-041 2712-042 2712-045 2712-046