Partial device for marking tensile specimens for manual elongation at break measurement

This newly designed device enables the efficient marking of tensile specimens with very precise pitch (5 mm pitch or as required). The marking length depends on your requirements and should correspond to the Lc (the parallel part of the tensile specimen). In your mechanical specimen production, an Lc that is approx. 2 mm longer should be provided. Alternatively, a pitch can be omitted so that the two outer marking teeth do not touch the radius.

The marking length can be easily changed using a pin. The marking comb is hardened (60 HRc) and has very sharp edges. This means that even hard sample surfaces can be provided with precise scratch marks. In order to be able to record the measuring marks even better, the tensile sample can/should be provided with a touch-up paint (spray can or sponge) before marking. If the sample surface is relatively hard, only the touch-up paint is removed and measurement with a caliper (under a magnifying glass) is possible in a simple manner.

The sample or the head of the tensile test specimen (cylinder head, shoulder head, threaded head - others on request) is held in the quick-action chuck on one side. On the opposite side there is a spring-loaded centering mandrel. In the case of samples produced on a lathe, there is usually a centering hole at at least one end of the tensile test specimen. This is required for the centering point installed on the left side.

For other Lc (L0) other marking combs are available with a pitch of 5 mm – other pitches on request.

The contact pressure is applied by a weight loading system and can be varied by moving the weight. Other weights can be designed as required.