FEP encapsulated O-rings
FEP-encapsulated O-rings have a core of elastomer that is completely covered with a seamless sheath of FEP fluoropolymer. The elastomeric core is normally either fluorocarbon (FKM) or silicone (VMQ).
An encapsulated O-ring is recommended when:
- A standard elastomeric O-ring has inadequate chemical resistance for a specific application
- A solid PTFE O-ring does not offer sufficient elasticity for reliable, long-term fluid sealing
They are used mainly in the chemical, petrochemical, food and pharmaceutical industries, and other sectors where high levels of chemical resistance or hygiene are required.
Although FEP encapsulated O-rings are most suited to static duties, they may also be used with slow, short movements on rotary applications such as valve stem sealing.
The benefits of FEP encapsulated O-rings include:
- Excellent resistance to a wide range of media - please consult our Technical Suppport Team for further advice
- Operational temperature ranges of
-60°C to +200°C with silicone core
-20°C to +200°C with fluorocarbon core
- Low friction and low 'stick-slip' effect
- Far better elasticity than solid PTFE
Our FEP encapsulated O-rings are fully interchangeable with standard elastomeric O-rings. However, due to the FEP sheath, they are less flexible than normal elastomeric O-rings and have limited stretch with higher permanent deformation. This means that auxilliary tools may be needed to facilitate efficient fitting.
FEP-encapsulated O-rings are supplied to order.