568-438 FKM 75 SQUARE CUT RINGS

The SV70438 is an AS568-438 black Viton® (FKM) 70 Shore A Square-Cut Ring supplied with an inside diameter of 6.225 in (158.12 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.775 in (172.09 mm). This square-cut ring presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.

Expect good resistance to petroleum oils and fuels, many acids, and aggressive chemicals. Viton® (FKM) is known for the industry benchmark where nitrile reaches its thermal limit and outstanding high-temperature capability. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. 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.

It sees regular use in aerospace, high-temperature process equipment, and semiconductor equipment.

Reference part number SV70438 when ordering; the item is sold individually. Nominal inside diameter is listed as 6 1/4 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.