FKM / Viton™

Fluorocarbon (FPM, FKM, Viton™)

Fluorocarbon is a well- known high performance rubber, and especially it has excellent resistance to high temperature, ozone, weather, oxygen, mineral oil, fuels, hydraulic fluids, aromatics and many organic solvents and chemicals.

Fluorine Content

Viton™ system gum like general type (A-TYPE, 66% fluorine), middle fluorine content type (B-, GBL-TYPE, 67~68.5% fluorine), high fluorine content type (F-, GF-TYPE,70% fluorine ), improving low temperature flexibility type (GLT-, GFLT) and excellent resistance to more chemicals and solvents-- Viton™ ETP Extreme.
We also can supply excellent acid and alkali resistance parts made by AFLAS®.

Cure system

Bisphenol cured vs. Peroxide-Cured

Standard FKM compounds are Bisphenol cured. FKM compounds with peroxide-cured possess better acid solution resistance than the bisphenol cured. In Some lubricants adding a few organic amide or amine, choosing peroxide curing system Viton™ will be better than bisphenol curing system.

Other Common Variations

  • FKM can also be submitted for approval to Underwriters Laboratories (UL) for use in applications as prescribed in UL157.
  • FKM has excellent resistance to high temperature, oil, solvent, flame, chemical and weather, and it is usually applied in automotive, chemical processing, aerospace and many industrials.
  • Viton™ GLT is broadly used in thermal range of -40℃ to 250℃ and it has outstanding resistance to aggressive HTS-type oils which are commonly used in aerospace industry.
  • Viton™ ETP is usually applied in chemical industrial. 
  • In some fuels adding several methanol, Viton™ F and B-type are more usable than A-type especially F-type. If it requires lower temperature, GFLT and GBLT will be available.
  • AFLAS® (TFE/propylene polymer) is better base and steam resistant than other general Viton™s. It can be use in amine, amide and some bases. 

Viton™ is a registered trademark of Chemours Fluoroelastomer. AFLAS® is a registered trademark of AGC Chemicals.

General Information

ASTM D 1418 Designation
Standard Color(s)
ISO/DIN 1629 Designation
Hardness Range
50-90 Shore A
ASTM D2000 / SAE J 200 Codes
Relative Cost

Service Temperatures

Standard Low Temperature
-26°C / -14°F
Special Compound Low Temperature
-40°C / -40°F
Standard High Temperature
250°C / 482°F
Special Compound High Temperature
275°C / 527°F

Performs Well In...

  • Petroleum products
  • Fuel or blend with methanol or ethanol
  • Diesel or blend with biodiesel
  • Mineral oil and grease
  • Silicone oil and grease
  • High vacuum
  • Ozone, weather and very high temperature air
  • Strong acid

Doesn’t Perform Well In...

  • Ketones
  • Low molecular weight organic acids (formic and acetic acids)
  • Superheat steam
  • Low molecular weight esters and ethers.
  • Phosphate ester based hydraulic fluids - Skydrol®️