Pneumatic Wedge Action Grips
Pneumatic wedge action grips are air powered grips that produce high clamp forces required to test high strength materials. We offer a wide range of grips with different force capacities, sample types and sizes. Our standard grips go up to 500 kN (112 kip) force capacity and 50 mm (2 in) thick. We also provide custom engineered solutions for more unique test samples. All of our pneumatic wedge action grips will fit any brand of test machine through the use of an adapter.
| Family | Max Force* | Max Thickness |
|---|---|---|
| G622P | 5 kN (1,125 lbf) | 9 mm (0.36 in) |
| G175 | 10 to 300 kN (2,250 to 67,000 lbf) | 33 mm (1.3 in) |
| G321 | 10 to 100 kN (2,250 to 22,500 lbf) | 42 mm (1.65 in) |
| G889 | 15 kN (3,375 lbf) | 5 mm (0.2 in) |
| G109P | 100 to 500 kN (22,500 lbf to 112 kip) | 50 mm (2 in) |
*Note force rating is at 7 bar (100 psi) air pressure. In most cases, the max clamp force can be doubled with optional 16 bar (230 psi) air supply
Fits Any Brand Test Machine
Our grips and fixtures will fit any brand of test machine. We offer adapters that allow the grips and fixtures to be used on test machines from TestResources, Instron®, MTS®, Tinius Olsen® and every other brand of machine.
Pneumatic Clamping Creates Higher Throughput and Better Repeatability
TestResources’ pneumatic grips deliver more accurate test results with less effort than comparable mechanical action grips. Some of the benefits of our pneumatic clamping, compared to mechanical action clamping, include:
Consistent Repeatable Clamp Load
Test repeatability is improved when all tests and samples are under the same constant clamping conditions which could vary with other clamps from test to test and user to user. The repeatability of pneumatic grips’ active clamping action makes it the ideal choice over mechanical grips. High elongation test samples shrink as they are pulled, this phenomenon is known as Poisson’s effect. For instance, as a rubber sample stretches, the sample shrinks. If you were to use a mechanical action grip to test a rubber sample, the sample will become thin and pull out of the jaws due to the rubber’s high Poisson’s ratio. Thanks to the active clamping action of our pneumatic cylinders, the pressure automatically adjusts to changing thicknesses and moves to hold a constant load regardless of the samples thinning.
Higher Throughput
Higher throughput is reached because our pneumatic grips provide efficiency through the fast clamping action to load and unload test samples instead of having to unscrew the grip each time. This is important in high production environments where many samples are being tested daily.
Less Operator Fatigue
Our pneumatic grips simplify operator activities, especially valuable in high volume test applications involving repetitive opening and closing actions such as supporting or being a part of a production line. This reduces the risk of repetitive strain injuries occurring on the job.
Wedge Action Grips Produce High Clamp Forces Required to Test High Strength Materials
TestResources’ wedge action design produces a highly leveraged strong clamp load that increases as the sample is tightened. As the grip jaws contact the specimen, the clamping force increases as the test load increases. When under load, our grip wedge action adds clamping pressure to minimize specimen slippage. The wedge action design creates natural and automatic centering of the sample specimen to the grip body. The natural centering produces reliable and repeatable alignment of the sample with the test machine’s centerline. We also offer optional centering tools for additional directions of centering which increase repeatability even more. Our wedge action grips are the ideal solution for tensile tests of hard round or flat high strength material.
We also offer mechanical and hydraulic wedge action grips. Hydraulic wedge action grips are needed when the initial clamping capacity of a pneumatic wedge action grip is not enough.
Can be Configured to your Specific Application
We can configure the grips and jaws to fit any sample geometry including round samples like wire and fasteners as well as flat test specimens with or without shoulder tab ends. Our experienced engineers will work with you to ensure your test system is configured to meet your specific application requirements.
Application examples:
- Composites
- Metals
- Wood
- Plastics & polymers
- Automotive components
- Aerospace components
- Wire & rods – Round shapes
Test types:
- Tensile tests
- Tension-tension cyclic tests
We can configure grips to match specific ASTM, ISO, DIN, EN requirements.
- ASTM A370 for Tensile Tests of Steel Products
- ASTM B557 for Tension Testing Wrought and Cast Aluminum
- ASTM D3039 for Tensile Tests of Advanced Composites
- ASTM E8 for Tensile Tests of Metals
And more...
Compatible with Different Testing Environments
Grips can be constructed of different materials and surface treatments such as stainless steel, titanium and nickel coating. Nickel coated versions can be used inside hot and cold temperature chambers. The nickel coating helps protect the grips from corrosion caused by condensation from the freeze/thaw cycles inside the chamber. It also protects the grips from moisture inside humidity chambers which helps protect the grips from rusting over time. Nickel coated grips or grips made from corrosion resistant materials such as 316 stainless steel or titanium have an important benefit to people whose labs are in humid climates or near coastal areas of the ocean. Stainless steel versions are used in harsh environments such as saline bathes.
Standard and Custom Engineered Solutions
We offer multiple standard products as well as custom solutions. Standard grips handle up to 500 kN (112 kip) force capacity and 50 mm (2 in) thick samples. However, our modular platform enables us to adjust designs for any application requirement including customized bodies and jaws for larger test samples. We understand that every sample can be unique. With this in mind, we offer custom engineered grips and jaw surfaces to match your specimen with any test force. Through the use of some of our standard elements, we can configure a wide variety of unique solutions without paying a “custom price” or waiting months to receive your order. Our modular platform approach satisfies virtually any application requirement.
Wide Range of Supporting Options
Interchangeable Jaws or Jaw Faces - We have various jaws available including standard jaws, wide width jaws, insert jaws and we can also easily custom engineer our jaws to fit unique test samples.
Variety of Jaw Surfaces - We offer a wide variety of jaw surfaces for various sample types including:
- Serrated
- Diamond grit coated and SurfAlloy
- Wave/ Corrugated serrated
- V serrated jaws for round samples
- We also offer custom made jaw surfaces
Specimen Centering Tool - The specimen centering tool provides a settable backstop to ensure repeatable specimen location. This will help keep the specimen appropriately aligned and orientated to the direction of pull, resulting in more consistent test results. This tool adds an additional direction of centering to the natural alignment that our wedge action grip design already produces.
Related Products
There are so many grips to choose from it can be overwhelming and you certainly don’t want to make the mistake of selecting the wrong one. Give us a call today to speak to one of our experienced engineers that will work with you to find the exact solution based on your test requirements.
