Encapsulated O-Rings

Not all o-rings are created equally. When it comes to chemical service applications Viton has it's limitations. Kalrez costs an arm and a leg, and PTFE while it may be chemically compatible, very limited capability to recover after it has been compressed.

Enter Encapsulated o-rings. Because they are coated with a sleeve of FEP (a product in the same family as PTFE), they are protected from chemical attack. The core is generally Viton or Silicone, which gives the o-ring the ability to recover it's shape after it has been compressed. Silicone cores are generally used in low temperature applications (to -75 F). Viton has better compression set characteristics and is recommended in applications to 400 F (constant).

Encapsulated o-rings are ideal in static applications, but in many situations have also been used in dynamic applications like mechanical seals. In dynamic applications they do have good wear resistance, however once the sleeve is worn through, it the cores can be attacked.
Encapsulated O-Ring Advantages
Technical Data
Creavy O-Rings
Temperature Range:
 -75 F to 440 F
Pressure: Vacuum to 10,000 psi
Overall Hardness:
85 Shore A +/- 5 durometer
FDA Compliant