Size: Standard and non standard
Color: Common is black, can be any color as you need
FEPM O ring is a subcategory of FKM O ring. Due to different composition monomer, there is a big difference of performance between them. Or we can say, FEPM enhance a lot onthe basis of FKM.
The full name of material FEPM is Tetrafluoroethylene propylene. A typical one, which you may heared about, is Aflas® which is a registered trade mark of Asahi Glass Co. (AGC).
Compared to the regular FKM, FEPM broadened the range of chemical resistant. For example, regular FKM is good at strong acids resistant, but not good at strong alkali/bases or steam. Well, FEPM does. It can resistant to both of them, as well as the steam. So you can cosnern to choose FEPM O ring seals when your working conditions have both strong acids and alkali.
Off course, FEPM can not resistant to every strong acid or alkali. For example, strong hydrofluoric acid is not idealy to choose any type of rubber, except the FFKM.
Additionally, FEPM is not compatible with aromatic and chlorinated hydrocarbons, and some fairly common organic solvents.
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