O-Ring Selection

Certain o-ring materials offer better chemical resistance while others offer better heat resistance or cold flexibility within your application. For specific chemical properties, refer to our Chemical Compatibility Guide. Some guidelines for the different types of o-rings:

• Buna-N: The most common o-ring material is Buna-N due to its solvent, oil and water resistance. It has a temperature range of -30° to 250° F.
• EPDM: Ethylene-propylene-diene rubber (EPDM, also sometimes referred to as EPR) is a chemically resistant family of compounds. CPC uses high quality peroxide cured EPDMs that provide exceptional resistance to temperatures with a wide range of chemicals.
• FFKM (Chemraz®, Simriz®, Kalrez®): Broadest range of chemical resistance of any elastomeric material, combining the resilience and sealing force of an elastomer with chemical resistance approaching that of PTFE.
• FKM: Well known for its outstanding resistance to heat, oxidation, weathering and ozone, FKM has a temperature range of -15° to 400° F.
• Food-grade: Commonly used when food, beverages or potable water is going through the coupling.
• PFA & FEP Encapsulated Seals: Encapsulated seals combine the resiliency of the elastomer with the superior chemical resistance of the fluoropolymer to achieve a seal that is lower cost than a pure fluoroelastomer FFKM seal.
• Silicone: Seals have good temperature resistance. The temperature range is -70° to 400° with special compounds that can reach 175° to 450° F. Silicone can also be supplied with Class VI requirements for life sciences applications.