Ordered as SV70277, this is an AS568-277 black Viton® (FKM) 70 Shore A Square-Cut Ring with an inside diameter of 11.484 in (291.69 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 11.762 in (298.75 mm). The square-cut ring offers greater contact area against the gland wall than an equivalent o-ring.
Viton® (FKM) is specified here for industry benchmark where nitrile reaches its thermal limit and long service life in hot, chemically aggressive environments. It resists aromatic hydrocarbons, petroleum oils and fuels, and many acids. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). 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.
It sees regular use in aerospace, chemical processing, and semiconductor equipment.
This item is sold individually under part number SV70277. 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 568-277 FKM 75 SQUARE CUT RINGS
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 11.484 inch (291.69 mm)
Actual_OD 11.762 inch (298.75 mm)
ProductCode Description O-Rings - Square/Quad - Commodity