Materials Program

FKM is a fluoroelastomer compound with exceptional mechanical properties.  The FKM elastomer gives the o-rings a faster recovery rate.  FKM has a Shore A hardness of 75 with an operating temperature range of -10F to +300F (-23C to +150C)


Silicone is well matched for applications that demand lighter compressive forces and higher temperatures.  Silicone has a Shore A hardness of 70 and an operating temperature range of -80F to +500F (-62C to +260C).
White (Special Order)

Cryolox Stainless 
Type 301/302 Spring

The spring energizer consists of precision rolled stainless material formed into a spiral spring, and encapsulated in a Teflon jacket.  It is well suited for a -420F to 500F. (-250C to 260C) temperature range.


EPDM is a type of synthetic rubber which exhibits favorable compatibility and resistance to heat, ozone and weather.  It is advisable to check a compatibility list concerning hostile environments.  It is well suited for -58F to 300F (-50C to 150C) temperature range.

Available by Special Order

Viton Extreme GF-S
Nitrile (Buna N)



The stainless FEP encapsulated seal was first used in the U.S. rocket development program associated with space exploration.   The stainless seal components are ideal in services such as flowing liquid oxygen and hydrogen, with extremely low cryogenic temperatures -420F (-260C).  Today  the cryogenic field has grown from very specialized applications to a broad spectrum of commercial uses in teh transportation, food preparation, pharmaceutical, medical and chemical processing industries.  When considering elastomeric seals, brittleness becomes a limiting factor that is a direct result of severe temperature drop.

Technical design considerations

The maximum stretching of Cryolox seals should never exceed 4%.  Stainless encapsulated seals are more suited for O.D. applications where stretching the diameter is limited.

The stainless steel spring has resilience but it should not be over compressed into the groove.  Compression guidelines are listed in the literature.

When stainless seals are exposed to pressures greater than 1300 PSI, they should be vented to prevent bursting of the encapsulation.  Three vent holes are placed at a predetermined location in the FEP or PFA jacket.

Cryolox Stainless Seal Advantages
Performs at high and low temperatures
High resilience
Minimal compression set