568-238 FKM 75 SQUARE CUT RINGS

Ordered as SV70238, this is an AS568-238 black Viton® (FKM) 70 Shore A Square-Cut Ring supplied with an inside diameter of 3.484 in (88.49 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.762 in (95.55 mm). The square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.

Viton® (FKM) delivers the industry benchmark where nitrile reaches its thermal limit and long service life in hot, chemically aggressive environments. Expect good resistance to petroleum oils and fuels, engine and transmission fluids, and aggressive chemicals. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). Applications involving low-molecular-weight organic acids or ketones and esters call for a different compound. The profile itself contributes greater resistance to extrusion than a round section of the same size and a flat contact band that spreads sealing load across a wider area. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.

Common environments for this compound include chemical processing, oil and gas, and high-temperature process equipment.

SV70238 ships individually. Nominal inside diameter is listed as 3 1/2 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.