To determine the breaking force and elongation of textile fabrics, we used a raveled strip test for woven fabrics, and a cut strip test for nonwoven, felted, and coated fabrics.
Raveled strip test specimens are commonly 25 mm, 35 mm, 50 mm, or 65 mm wide (plus 20 yarn strands, whichever is wider) and at least 150 mm long. We remove an equal number of yarns (or 10 yarns each) from each side in order to obtain a 25 mm or 50 mm testing width, which explains the term “raveled” strip test (there are provisions for using different size specimens under certain circumstances). The Cut Test uses either a 25 mm or 50 mm wide specimen that is at least 150 mm long.
We clamped the specimens with a grip distance of 75 mm (3 in) and pulled the strips in a tensile direction at 300 mm/min (12 in/min) until break. The test results that are relevant to these types of tests are the Breaking Force (Maximum Load) and Apparent Elongation.
While manual action grips with smooth flat faces will work, many of our users prefer the pneumatic action grips for ease of use, productivity, and better repeatability. Pneumatic action grips allow you to set a clamping pressure, while the manually operated grips depend on the operator's strength (which may not be so repeatable). We suggest to choose faces that are at least 10 mm wider than the specimen being tested, and at least 25 mm in height.
We find that gripping pressure and specimen alignment are very important in these tests. Too much gripping pressure can produce premature breaks, while not enough gripping pressure can lead to specimen slippage or breaks at or near the jaws. Materials testing software will help tremendously in these tests since it can correct for preload or pretension once the grips close or for slack if the specimen is held too loosely in the grips at test start.