EN
ZHTest Method: SATRA TM147
Resistance to stretching and flexing
March 2023
SCOPE
This method is intended to determine the resistance of an assembly to repeated stretching and flexing. The method is mainly applicable to footwear assemblies and in particular those which include the topline, but it can also be used to assess sheet materials, seamed uppers and components such as straps. The test is only suitable for toplines in which all of the reinforcing tape is stitched in, bagged toplines should be tested using SATRA TM143.
PRINCIPLE
A rectangular test specimen is mounted between two clamps on a test machine. The specimen is then repeatedly flexed and stretched at a constant speed for a pre-determined number of cycles and any damage to it is subjectively assessed.
There are two forms of the test, see Figures 5a and 5b:
Straight - In which the test specimen is clamped symmetrically with its shorter edges parallel to the clamps. This is primarily used to test straps and seams.
Edge tensioned - In which the specimen is clamped when distorted so that its shorter edges are at an angle of to the clamps. This applies the majority of the stretching force to one edge of the test specimen and therefore simulates conditions similar to those found in the topline of a shoe.
REFERENCES
Test Method SATRA TM143 – Whole topline strength test.
Test Method SATRA TM25 – Vamp flex test - resistance to creasing and cracking.
HISTORY
First issued June 1992. Revised March 2023.
AVAILABILITY
This test method is available to members and non-members.
PRICE (ex. VAT)
This price is for a printed copy of the Test Method.
- Members: £75
- Non-members: £215