Settlement (permanent deformation)

What is settling?

Pressure resistance refers to the resistance of a sample to pressure. It can therefore also be seen as spatial compactness. After removing the applied force
elastomers
are able to return to their original position.

The distance that is lost in the expansion is also referred to as the compression set. The compression set is standardized in accordance with DIN EN ISO 1856 by compressing test specimens between metal plates over a certain period of time. The expansion before and after the influence of pressure is then compared. Natural rubber, SBR, EPDM, NBR, ECO, fluororubber and silicone have a good (low) compression set.

The largest percentage of settling occurs within the first 48 hours under load. This is important when a machine or system needs to be precisely aligned, e.g. boat engine to propeller shaft.