Grip Jaw Face Solution for Tensile Specimens Cut from Pipe
When conducting tensile tests on sections cut from pipes, be
it plastic gas or water pipes or steel pipes, the resulting test specimen dumbbell
or “coupon” shape (dimensions of which are defined by the relevant test standard
be it ISO, ATSM, GB, GOST etc) exhibits the curve of the pipe, this means it
cannot generally be held for the duration of the tensile test using flat parallel
grip faces as the curvature of the specimen prevents a good amount of contact between
the specimen and the grip faces.
The solution is a grip face which mirrors the profile of the
curve in the pipe (dumbbell or coupon specimen) a V on one side and radius on
the other;
At Tinius Olsen we
are able to precisely manufacture and supply such faces to mirror the radius of
any curved specimen and implement in our tensile wedge action grips. The faces typically have
a 2 mm pitch serration and hardened to 60RC in support of good specimen
gripping. The faces are interchangeable for different size pipes, for cleaning
and eventually cost effective replacement when warn.
Comments