568-279 BUNA 70 SQUARE CUT RINGS

This square-cut ring is supplied in AS568-279 black Buna-N (Nitrile) 70 Shore A built to an inside diameter of 12.984 in (329.79 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 13.262 in (336.85 mm), catalogued under part number SH70279. It seals with a broad flat contact band instead of the line contact of a round-section ring.

As a material, Buna-N (Nitrile) is valued for strong abrasion and tear resistance, reliable performance in both static and dynamic service. This material stands up to propane and butane, water, and greases and lubricants. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where strong acids or polar solvents are present. The profile itself contributes a rectangular section that will not roll in the groove and simple lathe-cut manufacture at low tooling cost. 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 automotive, agricultural equipment, and general industrial maintenance.

Order part number SH70279, sold individually. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.