568-239 FKM 75 SQUARE CUT RINGS

Ordered as SV70239, this is an AS568-239 black Viton® (FKM) 70 Shore A Square-Cut Ring measuring an inside diameter of 3.609 in (91.67 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.887 in (98.73 mm). The square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.

As a material, Viton® (FKM) is specified for excellent resistance to compression set and permeation, the industry benchmark where nitrile reaches its thermal limit. The material holds up against aggressive chemicals, chlorinated solvents, and petroleum oils and fuels. The material carries a published service range of -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in amines or hot water and steam. The profile itself contributes simple lathe-cut manufacture at low tooling cost and a rectangular section that will not roll in the groove. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.

You will find this material specified across high-temperature process equipment, chemical processing, and oil and gas.

This item is sold individually under part number SV70239. Nominal inside diameter is listed as 3 5/8 inch. Check the compound against your process media, pressure and temperature before committing to a design.