FEP/PFA Encapsulated O-Rings

FEP and PFA are actually not elastomers, they are a plastic. Our FEP and PFA encapsulated o-rings consist of a seamless FEP or PFA jacket over an elastomer core made from Viton® or silicone. (Actually several options for the core material and shape are possible.) The combination of a chemically resistant polymer jacket over a low-compression set elastomer provides unique properties. In general, FEP and PFA encapsulated o-rings are chemically resistant and used to prevent the passage of corrosive fluids or gases in an application. While the outer FEP and PFA are resistive and hard, the core elastomer provides the memory of the o-rings when they are put under a compressive force.

Since FEP and PFA are practically chemically inert it means that the o-rings are able to resist almost all chemicals and keep the corrosive fluids and gases from getting through to the elastomer.

The extremely low coefficient of friction of FEP and PFA makes encapsulated o-rings an ideal choice when you are worried about surface wear.

FEP and PFA exhibits a useful service life over a wide range of temperatures, from below -100° F, to temperatures of over 500° F. Its resistance to solvents remains excellent throughout a wide range of temperatures also. In addition, the low dielectric constant and electrical resistance also remain intact throughout this range.

Advantages of FEP/PFA encapsulated o-rings:

• Chemically resistant
• Thermal stability from -76° to 500° Fahrenheit
• Low surface coefficient of friction (0.1 to 0.2)
• Low permeability
• Low compression set
• Economical, sometimes they replace o-rings or more expensive materials such as Kalrez®
• Non-stick surface for easy clean-up
• Eliminates contamination of fluids by elastomers
• Complies with FDA regulations
• Nonflammable
• Reusable
• High impact strength
• Easy to lubricate
• Smooth surface
• No swelling
• Low cold flow
• Wide range of sizes

Our FEP/PFA encapsulated o-rings consist of FEP or PFA encapsulated over a Viton® core or silicone core. They are manufactured in a variety of shapes and cross-sections to meet various applications.

Shapes of FEP/PFA encapsulated o-rings:

• Circle
• Square
• Rectangle
• Oval
• Half-circle

In addition, custom cross-sections such as solid Viton® or silicone square or rectangular cores are available. These are often used as gaskets in cam-action type couplings or as an alternative to PTFE or envelope gaskets in flange sealing applications.

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