scope:

The bend test may be used in conjunction with other tests to assess the performance of butt welded assemblies made from thermoplastics materials. Welded parts with comparable seam geometries, e.g. on profiles, can also be tested with reference to this guideline.

The bend angle, the ram displacement while bending and the fracture appearance when the test is terminated provide a guide to the ductility of a welded joint and hence the weld quality

The ductility properties of the material, the applied weld methods and the geometry of the test specimens influence the achievable bend angle resp. ram displacement and they have to be taken in consideration while evaluating.

The results derived from the bend tests can only partly be used to assess the long term behaviour of welded joints.

The bend tests can also be used to optimize welding parameters. In this case it is helpful to use none standard test conditions (e.g. to decrease the test temperature or to increase the speed of bending).