Viton™ o-rings, also know as FKM o-rings, are a type of fluorocarbon o-ring suitable for use in a number of specialised applications. They are widely used in aircraft, automotive and mechanical devices where a resistance to corrosive fluids and elevated temperatures are necessary. You’ll find these types of o-rings everywhere from inside the space shuttle to in your car gear box or garden hose.

The operating temperature of an FKM o-ring can range from -40°C up to as high as 250°C or higher. Its chemical resistance makes it highly suitable for use in engines and other applications where both temperature extremes and chemicals exist. It has low gas permeability, low compression set and excellent mechanical properties.

What about FFKM o-rings?

You may have heard of the FFKM o-ring technology and be interested in knowing what the difference is between this and Viton™ / FKM technology. These perfluoroelastomer compounds are generally used in applications where nothing else can quite meet the rigorous standards required by the operation. The benefit of these o-rings is that they maintain the incredible sealing power of elastomers like PTFE, while still offering all the benefits of a Viton™ / FKM o-ring.

FKKM is usually used in highly aggressive chemical processing, pharmaceutical applications, oil and gas recover as well as in semiconductor wafer fabrication. The brand names of these include Kalarez, Chemraz and Tecnoflon.

Not sure which o-ring you need?

If you’re unsure of whether FKM is suitable for your needs or whether you need to upgrade to FFKM specifications, talk to us for advice. With decades of experience in the industry, our mechanical engineering experts are on hand to offer advice and support in your choice. Call today for more information.

Also speak to our team about the Astra Seal® in which vigorous testing has shown outperforms FFKM for compression set resistancy.