Tensile Testing Device


(Carl Wilson) #1

Here are some pictures of the quick and dirty tensile testing rig I am making. I need to ensure that my solution heat treatment and artificial aging process will restore the strength of aluminium welds for my rocket engine project. So I am building this rig to destruction test some samples.

Force is applied by an enerpac jack and load inferred from a pressure gauge. Extension will be monitored using a Dti.

I could do this by electronic means, but for the purpose of these tests that would be over kill. It is possible to pick off a serial readout from most electronic calipers and I could use a pressure transducer. However, I don’t want this to become a project in it’s own right.


The test piece fits in the two slots and is held by bolts through the cross drilled holes. The enerpac jack bears against the outside edge of the rectangular frame and pushes against the box section on the threaded rods, thereby applying a tensile force to the test piece.

Based on the jack internal piston diameter, a pressure of 400 bar (6000psi) should exert a force of about 29KN. This is enough to part a test piece with an area of 90mm square.


(Carl Wilson) #2

Just put a long post on my blog regarding home heat treatment of aluminium weldments. This is central to the development of manufacturing technologies to produce an aluminium rocket engine. This is the bigger picture that the tensile tester is a part of.

You can read it at:-

Carl.