Freudenberg Fluorocarbon (FKM)

Freudenberg Fluorocarbon (FKM) Material Description:

FKM (fluororubber) is a high-quality material which can be adapted to different applications thanks to its variable composition.

By polymerization of vinylidene-fluoride (VF) and optional use of variable proportions of hexafluoropropylene (HFP), tetrafluoroethylene (TFE), 1-hydropentafluoropropylene (HFPE) and perfluoromethylvinylether (PMVE), it is possible to produce co-, ter- and tetrapolymers with different composition and fluorine contents between 65% and 71%. Thus, the material can be designed for different requirements in terms of chemical resistance and low-temperature flexibility. In the food industry, FKM is used in applications where temperatures above +140 °C (+284 °F) prevail in the process or where media are used which attack other elastomers such as EPDM or HNBR.

Freudenberg Seal Distributor

Engineered Seal Products is proud to be a "Freudenberg North American Preferred Partnered":

  • Involvement of engineering services and technical material know-how from Freudenberg Sealing Technologies
  • Highest technical seal competence through qualified training and certified sealing know-how
  • Efficient and speedy cross-linked processes with Freudenberg Sealing Technologies
  • High and quick availability assuring a reliable delivery performance
Freudenberg (FKM) General Properties:
  • Excellent temperature resistance
  • High chemical stability
  • Very good resistance to ozone, weathering, aging and oxygen
  • Excellent resistance to mineral oils and fats
  • Low gas permeability
  • Shows a very good resistance in non-polar media
  • Tends toward increased swelling in polar solvents, ketones and amines
  • Temperature stability from –25 °C to +200 °C (–13 °F to +392 °F)

Freudenberg Fluorocarbon (FKM) Compounds:

Compound Number Datasheet Hardness (Shore A) Low Temp High Temp Color Products
75 FKM 180497 PDF 75 +- 5 -25 200 Black O-Rings
70 FKM 37508 PDF 75 +- 5 -25 200 Red O-Rings, Molded parts, Diaphragms

ASTM Designation
Shelf Life
25 Years
Hardness (Shore A) Range
70 - 80

Temperature ranges will apply to the majority of media for which the material is potentially recommended. With some media however, the service temperature range may be significantly different. ALWAYS TEST UNDER ACUTAL SERVICE CONDITIONS.

ESP’s shelf life recommendation is based on the ARP 5316 standard and intended to be utilized by those organizations who do not already have specific recommendations for the control of elastomeric seals. It should be noted that the packaging of the elastomeric seals prior to assembly into a product is an integral part of the controlled storage procedure. It provides a positive means of product identity from the time of manufacture, to the time of assembly.