General Sealing Products / Solid Rubber Compound Grades

ASTM D-2000
Classification: HK

Custom Grades including MilSpec, Def STAN, NSN, AS & DTD available. Below is a sample of common grades. Contact us for your unique requirements.

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Temperature Range:

-26°C to +205°/230°C (-15°F to +400°/440°F)


Fluorocarbon elastomers have grown to major importance in the seal industry. Due to their extensive chemical compatibility, temperature capability, low compression set, and excellent ageing characteristics, fluorocarbon rubbers are the most significant single elastomers developed in recent history. Fluorocarbon elastomers are highly fluorinated carbon-based polymers used in applications to resist harsh chemical and ozone attack. Special compounds with improved chemical resistance are also available with new types always being developed. In general, with increasing fluorine content, resistance to chemical attack is improved but low temperature characteristics are diminished, however, speciality grade FKM’s are available that can provide high fluorine content with improved low temperature properties. The most well known brand of FKM is Viton®.


Fluorocarbon should be considered for use in aircraft, automobile and other mechanical applications requiring maximum resistance to elevated temperatures and too many fluids. FKM (FPM, Viton®, Fluorel®) resist mineral oils and greases, aliphatic, aromatic and special chlorinated hydrocarbons, petrol, diesel fuels, silicone oils and greases. It is also suitable for high vacuum applications.

Standard and Speciality Compounds

Type A and are commonly available in 75 & 90 Shore Hardness: – V75 & V90. These compounds are normally stocked in Black although other colours can be manufactured, i.e. Brown / Green. Other types are available

Type B – Generally used in Chemical Process plant, Power Utility Seals & Gaskets

Type F – Used for Oxygenated Automotive fuels. Concentrated aqueous inorganic acids, water, steam

Type ETP (also known as Viton® Extreme), offers excellent Chemical resistance and greater performance compared to standard compounds. Used for Automotive & Off Road – High pH lubricants, greases, & Coolants. Also used in Oil Exploration/ Production – Drilling Mud, Sour Wells. Special sealing requirements – solvents, coatings, ultra-harsh environments (ETP).

Additionally, speciality versions of these types are available to provide improved low temperature flexibility. These are called LT types, for example, GLT, and GFLT, and these perform like the A, and F families, respectively; GLT & GFLT have a wider temperature service range of – 35°C to 205°C.

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