PTFE Encapsulated

PTFE Encapsulated O-Rings

PTFE EncapsulatedPTFE is a superior O-Ring material not affected by most chemicals. It can be used at temperatures up to 500°F (260°C). It has the lowest coefficient of friction of any solid material. Lubrication is less critical and can sometimes be omitted.

Elastomers such as silicone or Viton® can be coated in a PTFE sheath for added chemical resistance while maintaining maximum flexibility. These rings are often used on food & pharmaceutical, chemical, and petrochemical industries where strong chemical resistance and hygiene are required.

Names: Teflon (® DuPont), PTFE, Polytetrafluoroethylene, PFA, FEP

PTFE Encapsulated O-Ring Information

Compound Info
ASTM D1418 DesignationFEP
ASTM D2000/SAE J200 Type, Class-
Hardness (Shore A)98
Colorwhite
Thermal Properties
Min Temp.-300°F (-184°C)
Max Temp.450°F (232°C)

PTFE Encapsulated O-Ring List

Jacket
Core
Image
Description
Temp. Range
FEP
Viton
FEP with Viton Core
This choice gives the best possible sealing characteristics due to the very low compression set value of the specially formulated Viton® core. Unless there are extreme high or low temperature involved, Viton® core should be the first choice.
-4° to 400°F
(-20 to 204°C)
PFA
Viton
PFA with Viton Core
The advantage of this combination is the extra abrasion resistance of the PFA jacket.
-4° to 400°F
(-20 to 204°C)
FEP
Silicone
FEP with Silicone
Whilst technically inferior to Viton® as a seal material, Silicone does have the ability to work at lower temperatures than Viton®.
-76° to 400°F
(-60 to 204°C)
PFA
Silicone
PFA with Silicone
Silicone combined with Pfa has a very flexible temperature range, especially at the higher end.
-76° to 500°F
(-60 to 260°C)
FEP
Hollow Silicone
FEP with Hollow Silicone
Used in applications where low loading requirements are necessary, i.e. glassware or similar delicate equipment. The seal compresses easier than a solid core ring.
-76° to 400°F
(-60 to 204°C)
PFA
Hollow Silicone
PFA with Silicone
Used in applications where low loading requirements are necessary, i.e. glassware or similar delicate equipment. The seal compresses easier than a solid core ring. This has a higher temperature range than the FEP counterpart.
-76° to 500°F
(-60 to 260°C)