This square-cut ring is supplied in AS568-145 black Viton® (FKM) 70 Shore A measuring an inside diameter of 2.55 in (64.77 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.756 in (70 mm), catalogued under part number SV70145. It seals with a broad flat contact band instead of the line contact of a round-section ring.
Expect good resistance to engine and transmission fluids, aromatic hydrocarbons, and aggressive chemicals. That behavior comes from the compound itself: Viton® (FKM) delivers outstanding high-temperature capability and very low compression set at elevated temperature. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Verify compatibility before use with amines or ketones and esters. The profile itself contributes a rectangular section that will not roll in the groove 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.
Maintenance and OEM teams specify it across semiconductor equipment, automotive fuel systems, and oil and gas.
Reference part number SV70145 when ordering; the item is sold individually. Review your operating media and conditions against this specification before installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.
Description -145 BLACK FKM 70D SQUARE RING
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 2.55 inch (64.77 mm)
Actual Outside Diameter 2.756 inch (70 mm)
Measurement System Imperial
Product Category O-Rings - Square/Quad - Commodity