This square-cut ring is supplied in AS568-336 black Viton® (FKM) 70 Shore A supplied with an inside diameter of 2.85 in (72.39 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.27 in (83.06 mm), catalogued under part number SV70336. It presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.
As a material, Viton® (FKM) is valued for outstanding high-temperature capability, excellent resistance to compression set and permeation. Expect good resistance to aggressive chemicals, chlorinated solvents, and aromatic hydrocarbons. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). It is not the right choice where low-molecular-weight organic acids or hot water and steam are present. The profile itself contributes a flat contact band that spreads sealing load across a wider area and greater resistance to extrusion than a round section of the same size. 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 semiconductor equipment, automotive fuel systems, and high-temperature process equipment.
SV70336 ships individually. Nominal inside diameter is listed as 2 7/8 inch. Review your operating media and conditions against this specification before installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description 568-336 FKM 75 SQUARE CUT RINGS
Actual Cross Section 0.21 inch (5.33 mm)
Actual Inside Diameter 2.85 inch (72.39 mm)
Actual Outside Diameter 3.27 inch (83.06 mm)
Measurement System Imperial
Product Category O-Rings - Square/Quad - Commodity