high-temperature, broad-chemical-resistance workhorse.
Excellent in oils, fuels, solvents, and outdoor exposure.
| Feature | Details |
|---|---|
| Also called | FKM, FPM, Viton® (Chemours trademark) |
| Typical service temp | –15°F to +400°F (special low-temp FKM like GLT/GFLT can reach ~–40 to –60°F) |
| Hardness range | 55–90 Shore A (common: 75, 90) |
| Variations | A / B / F (fluorine level), GLT/GFLT (low-temp), ETP/Extreme (wider chemical) |
| Cure systems | Bisphenol (fast cure, good CS) • Peroxide (better for aggressive media/steam) |
| Actual limits vary by compound and media—verify in your service conditions. | |
BEST FOR
- ✔ Need high temp sealing (to ~400°F)
- ✔ Broad chemical exposure: oils, fuels, many solvents
- ✔ Ozone/UV/weather resistance (outdoors)
- ✔ Vacuum, aerospace/automotive, oil & gas service
Not For
- ✘ Amines / strong alkalis
- ✘ Glycol brake fluids
- ✘ Low-MW esters/ethers, ketones, certain organic acids (e.g., formic/acetic)
- ✘ Hot water/steam long-term (use EPDM or specialty grades if required)
Popular FKM Options
- General Purpose: 75A and 90A FKM (black/brown)
- Low-Temp FKM (GLT/GFLT): improved cold flexibility
- Rapid Gas Decompression (RGD)-Resistant grades (75–95A)
- ETP/Extreme FKM: expanded chemical resistance
- FDA/3-A selections; metal/X-ray detectable; high-visibility colors
- Inch (AS568) and metric sizes; customs on request
- (Genuine Chemours Viton® compounds available upon request.)
Engineering Notes
- Fluorine content trade-off: more fluorine ⇒ better fluid resistance, poorer low-temp flexibility (A < B < F).
- GLT/GFLT: ether-containing FKM for low-temperature service with strong chemical resistance.
- ETP: perfluorinated cure site monomer—widest chemical resistance among FKMs.
- Bisphenol vs Peroxide cures: peroxide grades handle steam/acidic media better; bisphenol offers excellent compression set and cure speed.
- Applications:
- Engines & fuel systems • Chemical processing • Aerospace • Oil + Gas tools • General industrial equipment. (Detectable and high-visibility options available for process safety / identification.)