Wrap Grips for Universal Testing Machines
Products > Tensile Grips > Wrap
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Wrap Grips are also known as webbing grips or capstan fixtures and are designed for tensile testing of flat cordage - ribbons, slings, straps, tarpaulin, and webbing. The flexible material is wound around the wrapping column and then secured with locking pins prior to the tensile test. These grips are ideal for high-strength textile webbing materials that are used in industrial applications such as shipping and construction.
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Custom Wrap Grips are also available on request. Special capstan grip projects that have been completed include extra wide grips and also a center wrapping drum with a knurled finish.
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ASTM
A1023
D4268
D2256
How to use Capstan Grips
Capstan Grips are easy to use, however there are a few pointers that should be noted.
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1. Orient both fixtures so that they are facing the same way. They should mirror each other, rather than being offset.
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2. Arrange the sample so that the connected end of the ribbon is aligned along the centerline of the apparatus.
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3. Always use both locking pins if there are 2. (20kN and up)
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4. If the sample is slipping, try wrapping it around several more times.
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5. Be sure to stand away from the machine when it is in operation. Test breaks from webbings, capstans, slings, and similar materials can be violent. Safety Glasses are recommended.
225 lb. Small Webbing Grip - 1kN
These types of grips and fixtures are different than the previous wrap grips because they are designed for wider samples. Ribbons, Straps and Webbings are tested with these grips.
1K lb. Webbing Grip - 5kN
These grips are perfect for testing ribbons and smaller strap type materials. They are a cheaper option because they are designed only to test narrow bands of about 1 in. in width.
2K lb. Webbing Grip - 10kN
These grips are slightly more robust than the smaller versions. To attach a webbing, guide the end through the center opening and wrap the sample on top of itself. Secure the ribbon by using the locking pin. Please see the Literature for more information
4.5K lb. Webbing Grip - 20kN
These webbing and strap grips are used on dual column Universal Testing Machines.
11K lb. Webbing Grip - 50kN
This version of the web fixture is made specifically for thinner ribbons. The working principle is the same but the design is more compact. A male adapter is pictured here.
22K lb. Big Webbing Grip - 100kN
The largest webbing grips use two locking pins instead of one. There are several different sizes for the center drums. Other options include substitute metals suitable for environmental chambers, and knurled or bumpy cylinder surfaces.