568-358 FKM 75 SQUARE CUT RINGS

Ordered as SV70358, this is an AS568-358 black Viton® (FKM) 70 Shore A Square-Cut Ring with an inside diameter of 5.6 in (142.24 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 6.02 in (152.91 mm). The square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.

It resists petroleum oils and fuels, engine and transmission fluids, and chlorinated solvents. That behavior comes from the compound itself: Viton® (FKM) is known for very low compression set at elevated temperature and long service life in hot, chemically aggressive environments. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in low-molecular-weight organic acids or ketones and esters. 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 automotive fuel systems, oil and gas, and high-temperature process equipment.

Reference part number SV70358 when ordering; the item is sold individually. Nominal inside diameter is listed as 5 5/8 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.