FKM O-ring, also known as FPM or Viton® O-ring, is manufactured from fluorine-based elastomers with excellent thermal stability and chemical resistance. The material is specifically developed for sealing applications exposed to oils, fuels, solvents, and elevated operating temperatures. Compared with conventional rubber O-rings, FKM maintains elasticity and sealing force under more demanding conditions, ensuring stable performance over long service periods.
The sealing mechanism is based on elastic deformation of the sealing ring inside a precision-machined groove. Once installed, the FKM O-ring generates contact pressure against the mating surfaces, creating an effective seal in both static and dynamic assemblies. In static applications, resistance to compression set is critical, while in dynamic applications, abrasion resistance and shape stability become key performance factors.
FKM O-rings are available in a hardness range from 60 to 90 Shore A, allowing adaptation to different pressure levels, clearances, and motion types. Higher hardness improves extrusion resistance under pressure but increases installation force, so hardness selection should always be matched with groove geometry and operating conditions. For high-pressure applications or larger clearances, the use of PTFE or polyamide back-up rings is recommended.
Features of FKM O-ring
Wide operating temperature range from -20°C to +200°C, with short-term exposure up to +230°C depending on compound.
Excellent resistance to oils, fuels, lubricants, ozone, and weathering.
Low gas permeability, suitable for vacuum and pressurized systems.
Good resistance to compression set, ensuring long-term sealing reliability.
Available in multiple compounds and curing systems to match specific chemical and thermal requirements.
Applications
Hydraulic and pneumatic sealing systems operating under elevated pressure.
Fuel, oil, and lubricant handling equipment.
Pumps, valves, compressors, and rotating machinery.
Chemical processing and industrial equipment exposed to aggressive media.
Energy, petrochemical, pharmaceutical, and general mechanical engineering applications.
Chemical Compatibility
FKM O-ring materials show high compatibility with mineral oils, synthetic oils, fuels, aromatic hydrocarbons, and many industrial solvents. Compatibility with aggressive media such as hot water, steam, ketones, amines, and glycol-based fluids depends on the specific compound, temperature, and exposure time. For critical applications, material selection should be verified through compatibility testing.
Standards & Availability
FKM O-rings are manufactured in accordance with ISO 3601, DIN 3771, and AS568 standards.
AS568 standard sizes are widely used in hydraulic, pneumatic, and industrial sealing systems, particularly for inch-based equipment and assemblies.
The AS568 designation defines the O-ring dimensions by inside diameter and cross-section, ensuring interchangeability across different manufacturers. FKM O-rings are available in the full range of AS568 sizes, including common series for static and dynamic applications.
In addition to standard AS568 sizes, QZSEALS supports custom FKM O-ring manufacturing based on drawings or specific dimensional requirements. Compound selection, hardness, and tolerances can be adjusted to match operating pressure, temperature, and chemical exposure.
Reviews
There are no reviews yet.