This method is used to investigate the peel strength of a touch and close fastener. It should be understood that peel tests for touch and close fasteners involve complex stress distribution. When a touch and close fastener is peeled open, forces relating to the bending of monofilaments and the individual tapes and the
breaking strength of individual filaments all play a part in the resultant stress.
A touch and close fastener comprises of two narrow, woven, pile fabric tapes. The male tape is constructed with monofilament warp ends, finished to form locking elements of either ‘hook’ or ‘mushroom’ shape. The female tape is constructed with multifilament yarns. On presenting the two tapes to one another, pile to pile, the male and female elements engage to form a secure closure which can be separated by a peeling action from either end.
The EN 12242 test method is suitable for testing of mated component tapes of a touch and close fastener and are separated at a constant rate in a peeling action from an open edge of a prepared closure. This is carried out such that the separation occurs progressively along the closure in a direction parallel to the length of the tapes forming the closure. This method is for the determination of average peel and the peel strength characteristics of the product for a given rate of displacement.
In principle the free ends of the test specimen is supported between two clamping jaws and is peeled apart for a given length at a constant rate of displacement. To record the test it is important to have a high speed intelligent test data logging rate transfer to the PC of 100Hz or more to capture and record all the peaks and troughs.
We suggest using pneumatic action grips with rubber coated jaw faces for clamping of the material fitted to a tensile testing machine. While manual action grips will work, many of our users prefer the pneumatic action grips for ease of use, productivity, and better repeatability. These 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 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. Tese grips arte usually fitted to single-column or dual-column table-top design. The use of testing software, such as Bluehill® 2, test method is used to input specimen details, set the desired test control, automatically calculate the desired results and statistics and produce a test report all in accordance with the standard.
We suggest reviewing EN12242 to fully understand the test fixture and results requirements.