About Harboro Rubber Engineering in Rubber      Contents      Introduction      Uses of Rubber      Processing Rubber      Designing With Rubber      Selecting / Specifying Rubber      Quality In Rubber      Rubber Directory      Health & Safety      Measuring Properties          Measuring Properties          Measuring Hardness          Tensile Strength          Elongation          Modulus          Compression Set          Permanent Set (Tensile Set)          Density (Specific Gravity)          Resilience          Chemical Resistance          Fluid Resistance          Weather Resistance          Ozone Resistance          Electrical Properties          Tear Strength          Abrasion Resistance          Electric Strength          Flame Resistance          Low Temperature          Staining          Accelerated Ageing      Glossary of Terms      Request A Copy Contact Information

Compression Set Property: Compression Set Method of Measurement: A cylindrical button of rubber of known thickness is compressed to a fixed height (typically 70% or 75% of its original height) at a defined temperature for a specified period of time. The button is then released, allowed to recover (typically for 30 mins) and the thickness is measured. Compression set is the height that is not recovered expressed as a percentage of the amount by which it was compressed. ASTM REFERENCE: D395 BS REFERENCE: BS903 Part A6 ISO REFERENCE: ISO815* * technically equivalent ** identical