568-031 FKM 75 SQUARE CUT RINGS

The SV70031 is an AS568-031 black Viton® (FKM) 70 Shore A Square-Cut Ring with an inside diameter of 1.739 in (44.17 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.879 in (47.73 mm). This 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, aromatic hydrocarbons, and engine and transmission fluids. That behavior comes from the compound itself: Viton® (FKM) is valued for the industry benchmark where nitrile reaches its thermal limit, excellent resistance to compression set and permeation. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). Applications involving ketones and esters or hot water and steam call for a different compound. The profile itself contributes greater resistance to extrusion than a round section of the same size 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.

Common environments for this compound include oil and gas, automotive fuel systems, and chemical processing.

SV70031 ships individually. Nominal inside diameter is listed as 1 3/4 inch. Check the compound against your process media, pressure and temperature before committing to a design. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.