Elastomeric materials are frequently tested in the form of rings either because the finished product is an "O" ring or because ring shaped samples can be readily prepared.Tensile testing of ring specimens requires a special fixture.
Principle of Operation
Designed for testing elastomeric materials in the form of rings, these fixtures avoid local stress concentrations by using a lower spindle that is rotated by a toothed belt driven from the moving crosshead.
The upper spindle rotates freely and the rotation frequency of the lower spindle is easily selected by moving the toothed belt from one pulley to another.
The simple drive mechanism avoids the need for lubricants or separate electric motors.