Viton (FKM) O-Rings

Viton ® (FKM) O-rings offers increased oil, solvent and chemical and heat resistance than other common elastomers. Viton ® O-rings are readily available off the shelf in black or brown color. The Viton ® O-rings heat resistance makes it optimal for application that exceed +400°F temperatures and where excellent chemical resistance is required. FKM offers excellent resistance to sunlight, weathering and ozone. Viton ® O-rings are used in a variety of demanding aerospace, chemical Industry, oil and gas, and automotive application.

Viton ® O-rings come in several grades or types of copolymer or terpolymer of vinylidene fluoride (VF2), hexafluoropropylene (HFP), tetrafluoroethylene (TFE) with a bisphenol or peroxide cure. The various grades of standard Viton ® O-rings have various fluorine content ranging from 66% (Type A), 68% (Type B) and 70% (Type F) fluorine content (wt%). As the fluorine content increases so does the fluid resistance, however, compression set and low temperature flex resistance decreases. The most common grade is Type A which is a copolymer of VF2 and HFP with a 66% fluorine content and bisphenol cure which offers a good balance fluid resistance, compression set and low temperature flexibility. Viton ® O-rings in Type A are readily available off the shelf in most AS568 standard O-ring sizes.

Specialty types of Viton ® O-rings include B70, GLT, GFLT and ETP, Types GLT and GFLT offer increase low temperature flex resistance and increase chemical resistance. GFLT Vitons O-rings are typically used in biofuel vehicles because of its resistance to methanol.

Viton Extreme ® O-rings made with tetrafluoroethylene (TFE) and perfluoromethylvinyl (PMVE), unlike standard grades of Viton ® O-rings are resistant to low molecular weight esters, keytones, aldehydes and amines. Specialty types of Viton ® O-Rings are used in the aerospace, chemical and oil and gas industries due to their excellent chemical resistance and low temperature flexibility.

Automotive Industry

Viton ® O-rings are used throughout the automotive, chemical, and filter industries because of their fuel, chemical and heat resistance. They are used in the fuel systems of automobile on fuel injector O-rings and in the fuel pumps. A high grade Viton ®, GFLT, is terpolymer of VF2, TFE, and perfluoromethylvinylester (PMVE) with a fluorine content of 67% and peroxide cure. Viton ® GFLT O-rings are used primarily in biofuel vehicles because of their compatibility with both gasoline and biofuels. Viton ® O-rings are also used in the automotive industry as head and manifold gaskets, fuel lines, quick connector O-rings, injector and valve seals.

Chemical Industry

Viton ® O-rings are also used in the chemical industry in both filters and valves due to its resistance to a wide range of chemicals, fuels, oils, solvents, and acids. Viton ® elastomers have great resistance to sunlight, weathering, and ozone. Viton ® has excellent resistance to heat and can withstand temperatures well into the +400°F [+200°C] range compared to Nitrile elastomers which have a maximum temperature range of +212°F [100°C]. Viton ® O-rings can withstand low temperatures to around -10°F [-23°C] and can be compounded to resist lower temperatures.

If the standard grade of Viton ® O-rings do not offer the resistance your application requires then the next step would be to look at high grade Viton ® O-rings such as Viton ® GLT and GFLT grades, Aflas ® (TPE/P, FEPM), or perfluorelastomer (FFKM). If it’s heat resistance your looking for, not much compares to the broad temperature range of Silicones O-rings which range form -65°F[ -53°C] to +600°F [+315°C].

Satori Seal supplies large quantities of Viton ® O-rings for many industries and applications. With over 48 years of experience in providing both standard and custom Viton ® O-rings, Satori Seal can provide you with the best solution for your business. Contact our engineering or sales team for answers to your Viton ® O-ring questions.

There are many factors to consider when designing a Viton ® O-ring for your application — dimensions, temperature range, fluid contact, dynamic or static seal to name a few. From there you can specify other criteria or work with one of our sales team to help select the ideal O-ring.

Viton® is a registered trademarks of The Chemours Company.

AFLAS ® is a registered trademark of Asahi Glass Co., Ltd.