University of Connecticut utilizes ADMET  testing equipment for research and classroom work requiring mechanical testing. In the video below, Adam Wentworth (current Senior Research Engineer at Brigham and Women’s Hospital and Research Affiliate at MIT Koch Institute for Integrative Cancer Research) goes over the setup of ADMET  high-capacity wedge grips on an eXpert 1655 servohydraulic UTM and gives tips on grip operation. 

High-Capacity Wedge Grip Design

GW-XT wedge grips are high capacity tensile grips that are offered in capacities from 100kN (22,480lbf) to 500kN (110,000lbf). They are suitable for high-strength materials such as metals. GW-XT wedge grip design features a door with a crank to open and close the grip jaws. 
Wedge grip setup

The video starts by displaying the initial setup of the GW-XT wedge grips and how the grip doors are opened and closed. As the specimen is tightened between the grip jaws, and tensile force is applied, the wedge action mechanism increases the clamping strength applied on the specimen. 

Adam also shows the serrated jaws of the grips and shares some tips on checking the marks on the serrations after test completion to ensure slippage did not occur during the test. 

Wedge grip setup

ADMET grips come with female eye ends and a pin to secure the grips in place. If grips need to be removed, the pin should be removed and the nuts loosened with the spanner wrench supplied to you with the ADMET grip and fixture adapter package. 

Full Test Setup

Testing Machine

The test setup in the video includes eXpert 1655 servohydraulic testing machine rated to 150kN equipped with MTESTQuattro PC-based controller and high-capacity wedge grips. ADMET hydraulic UTMs come with load cells for direct measurement of force. The hydraulic power supply and electronics are integral with the frame thereby saving valuable lab space.

eXpert 1600 series hydraulic universal testing machines are capable of performing static tension, compression, and bend tests. eXpert 1900 series hydraulic testing systems are designed for dynamic testing of materials requiring high loads. See table below for further specifications.

eXpert 1000 Specification Chart

For more information on ADMET servohydraulic testing machines, click here.

Grips

ADMET offers a variety of tensile grips including manual vise, wedge, pneumatic vise, pneumatic wedge, and hydraulic grips. In addition, more specialized designs such as rope and thread grips and scissor grips are offered for samples with different geometries and dimensions. Choosing the most appropriate tensile grips to effectively secure your samples is critical in getting accurate measurements of tensile properties such as tensile strength, peak load, elongation, tensile modulus, and yield. Read our blog post below on the different types of tensile grips and the selection criteria.

TENSILE GRIP TYPES & SELECTION

Extensometer

An axial extensometer was supplied to University of Connecticut for strain measurement purposes. Axial extensometers provide strain data by clipping onto the specimen with their knife edges and measuring the displacement in length as load is applied and the specimen is pulled. Extensometer selection depends on the gauge length and travel range of your samples. Click below for more information.