This square-cut ring is supplied in AS568-365 black Buna-N (Nitrile) 70 Shore A with an inside diameter of 6.975 in (177.17 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 7.395 in (187.83 mm), catalogued under part number SH70365. It presents a flat rectangular section that cannot roll or twist in its groove, making it a dependable static seal.
As a material, Buna-N (Nitrile) is specified for strong abrasion and tear resistance, the most widely specified general-purpose sealing elastomer. It resists propane and butane, many alcohols, and hydraulic fluids. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving ozone and direct sunlight or ketones 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 agricultural equipment, construction equipment, and automotive.
Reference part number SH70365 when ordering; the item is sold individually. Check the compound against your process media, pressure and temperature before committing to a design.
description 568-365 BUNA 70 SQUARE CUT RINGS
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 6.975 inch (177.17 mm)
Actual_OD 7.395 inch (187.83 mm)
ProductCode Description O-Rings - Square/Quad - Commodity