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what is FKM o ring applications?

Jul 10, 2018

What is FKM o ring applications?

The performance of fluoroelastomers in aggressive chemicals depends on the nature of the base polymer and the compounding ingredients used for molding the final products (e.g. O-rings). This performance can vary significantly when end-users purchase Viton polymer containing rubber goods from different sources. Viton is generally compatible with hydrocarbons, but incompatible with ketones such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate, amines, and organic acids such as acetic acid. O-rings made of Viton are typically color-coded as black, but new gaskets, seals and O-rings should be green FKM or black FKM, but with a green mark on the outer edge.

Viton O-rings have been used safely for some time in SCUBA diving by divers using gas blends referred to as nitrox. Viton is used because it has a lower probability of catching fire, even with the increased percentages of oxygen found in nitrox. It is also less susceptible to decay under increased oxygen conditions.

Viton is used in after-market float valves ("needle and seats") for SU carburettors, for its fuel resistance and resiliency for sealing.

Viton tubing or Viton lined hoses are commonly recommended in automotive and other transportation fuel applications when high concentrations of biodiesel are required. Studies indicate that types B and F (FKM- GBL-S and FKM-GF-S) are more resistant to acidic biodiesel. (This is because biodiesel fuel is unstable and oxidising.)

Viton o-rings are an alternative to Buna-N seals in BMW's automobile engine variable timing units, known as VANOS. In the VANOS, the Buna-N o-rings deteriorate. The Viton fluorocarbon o-rings have similar functional characteristics to Buna-N, but with much higher temperature and chemical resistance characteristics.

Viton/butyl gloves are highly impermeable to many strong organic solvents that would destroy or permeate commonly used gloves (such as those made with nitriles).

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