Frequently Asked Questions About FFKM O-Rings 1. What is the difference between FKM and FFKM? While both are fluorinated elastomers, FFKM (Perfluoroelastomer) contains more fluorine than standard FKM (Fluoroelastomer). This higher fluorine content, along with a fully fluorinated backbone, gives FFKM near-universal chemical resistance and a much higher thermal ceiling (up to 327°C vs. 200°C for FKM). 2. Is FFKM the same as Kalrez®? Kalrez® is a brand name for FFKM manufactured by DuPont. As an independent FFKM O-ring supplier, Hydro Seals offers high-performance perfluoroelastomer compounds , brands like Kalrez®, Chemraz®, or Perlast®, often with better lead times. 3. Why are FFKM O-rings so expensive? The high cost of FFKM is due to the complex chemical synthesis required to create the perfluoroelastomer base and the specialized curing agents used. However, because they prevent catastrophic equipment failure and reduce maintenance cycles in harsh environments, they offer a significantly lower Total Cost of Ownership (TCO). 4. Can FFKM O-rings be used in steam applications? Yes, but you must select the correct grade. While standard FFKM is excellent for chemicals, specific Steam-Grade FFKM is required for high-temperature steam (up to 250°C) to prevent hydrolysis and material degradation. 5. What is the shelf life of an FFKM O-ring? FFKM has an unlimited shelf life when stored correctly (away from direct sunlight and extreme temperature fluctuations). Unlike nitrile or natural rubber, FFKM does not degrade over time under normal storage conditions.