Test standards Alpine supports: ASTM D395, ASTM D1414
Compression set testing is used to evaluate an elastomer’s ability to maintain elastic recovery after prolonged deformation. A specimen is compressed to a specified strain (usually 25%) and is then aged at ambient conditions, elevated temperature, or a combination of fluids/pressure/temperature. After cooling, the amount of permanent deformation is expressed as a percentage of the original height, indicating how well the material resists permanent compression.
Compression set is a fundamental test for determining long-term seal performance. A high compression set may suggest a material is prone to losing its ability to maintain contact pressure, which can lead to leaks in dynamic temperature/pressure sealing applications. This test is commonly used to evaluate materials for O-rings, gaskets, and other components subjected to dynamic pressures and temperatures in harsh environments. Examples of test fixtures can be seen below.
Alpine performs compression set testing in accordance with international standards using precision equipment and controlled aging environments. Our team works closely with customers to simulate custom and real-world application conditions and provide clear, actionable data on material performance.
Alpine Expanded Capabilities
Test conditions we support:
- Custom fixtures for different specimens
- Custom specimen preparation
- Aging in acids, bases, brines, hydrocarbons, and extreme pressure
- Cryogenic to 400°C aging capabilities
Alpine offers compression set testing to evaluate the permanent deformation of elastomers and other sealing materials after compression under specified conditions. We provide custom specimen preparation and custom fixtures to accommodate a variety of specimen sizes and geometries for accurate, application-relevant testing. Materials can be aged in acids, bases, brines, hydrocarbons, and under extreme pressures, with cryogenic to 400°C aging capabilities, ensuring that compression set data reflects true performance under demanding service conditions.
Testing Details
In a compression set test, the sample (cylinder or O-ring) is compressed by a known percentage of its thickness. The specimen is then placed in the testing environment, which can consist of various gases, liquids, be at high temperature or pressures, or a combination of these factors. Once the exposure is complete, the specimen is then cooled to room temperature before measuring final thickness. Compression set is calculated as the percentage of permanent deformation from the specimen’s original thickness. These changes are permanent deformation. The lower the compression set value, the more resistant the material is under the testing conditions. Compression set testing is typically conducted according to ASTM D395 for rubber sample material and ASTM D1414 for O-rings.