Seal Rotating or Swivelling Machine
Standard FKM shaft seals — Types OS-F10 & OS-F11 metal case fully covered
Shaft seals are used on rotating or swiveling parts like shafts to stop oil, grease or dirt from leaking. They are common in many machines and equipment.
For types OS-F10 and OS-F11 the usual material is brown FKM 80 (a fluoroelastomer). The spring is stainless steel (grade 1.4301) and the metal housing is carbon steel made to the DIN EN 10139 standard.
Other rubber materials that can be used are: NBR (nitrile), VMQ (silicone), ACM (polyacrylate), HNBR (hydrogenated nitrile), CR (neoprene) and EPDM.


Fitco Oring FKM rotary seals — Types OS-F10 & OS-F11
The OS-F11 has an extra protective lip to keep out dirt and other outside contaminants. This design is very flexible so it can be used in many different applications. The metal case is completely covered with elastomer and the sealing lip is held in place by a stainless steel spring. You do not always need to know the exact use to choose it. If FKM is only needed for heat resistance, you can safely choose the cheaper OS-A10 instead.
Application parameters for the standard materials combination:
Temperature: -25°C to +160°C
Pressure: depressurized, max. 0,05 MPa
Shaft speed: acc. to chart
Media: mineral oil based lubricants, synthetic lubricants, fuels, aromatic and chlorinated hydrocarbons, good resistance to many chemicals