CSI-6 (Compressibility Test Fixture )
The CSI Compressibility Test Fixture is used for the determination of the short-time compressibility and recovery properties of laminated composite gasket materials, form-in place gaskets, and in certain cases, gaskets cut from sheets. It is not a test intended for compressibility under prolonged stress application, generally referred to as “creep” or for recovery following such prolonged stress application, the inverse of which is generally referred to as “compression set.”

The fixture measures compressibility with a matched pair of opposing upper and lower penetrators, which provide better precision and bias than methods using an upper penetrator and lower anvil. It is difficult to prepare undistorted test specimens from laminated composite gasket materials, which will lay flat on an anvil. Also, with many composites having rigid inner layers the load on the upper penetrator is distributed over inner layers the load on the upper penetrator is distributed over the bottom anvil which results in a lower than actual compressibility reading.

This apparatus includes:

Heavy Duty steel body construction.
Dial Indicator, .025-mm resolution.
Three matching Penetrators (mm): 6.4, 12.8, 28.7 diameter, flat.
Preload: 22.2N.

References:
ASTM F 36, F 806