CSI-71 (Indentation and Compressibility Tester )
The CSI Indentation and Compressibility Tester is the most suitable instrument for testing the short-time compressibility or indentation and recovery of gasket materials, resilient floor coverings when subjected to a concentrated load under controlled conditions.

Generally these determinations are of short time duration, as opposed to “creep” or “compression set” type compressibility and recovery tests. Applicable materials may include, resilient nontextile floor covering such as vinyl plastics, cork, felt backed materials, linoleum, and similar materials.
The apparatus features a lower anvil supported at the bottom by a massive base. A penetrator or indenter, consisting of a flat-ended cylindrical steel rod, spherical steel ball or other shapes as desired. The indenter is attached to the lower end of the indenting plunger, attached to the plunger is an adjustable stop which contacts the spindle of a dial/digital indicator micrometer attached to the frame of the machine. The dial micrometer is set to zero, when the foot touches the base platen. In this manner the indicator can register the thickness of the specimen during the test.
The desired load is applied via dead weights that are placed on a weight holding rack. The load can gradually and smoothly be applied.

References:
ASTM F 36, F 806, F 1914, F 970
Fed. Std. No. 501A - Method 3221 Procedure