568-339 BUNA 70 SQUARE CUT RINGS

This square-cut ring is supplied in AS568-339 black Buna-N (Nitrile) 70 Shore A measuring an inside diameter of 3.225 in (81.92 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.645 in (92.58 mm), catalogued under part number SH70339. It offers greater contact area against the gland wall than an equivalent o-ring.

The compound resists propane and butane, greases and lubricants, and hydraulic fluids. Buna-N (Nitrile) is known for reliable performance in both static and dynamic service, strong abrasion and tear resistance. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in ketones or polar solvents. 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 hydraulic and pneumatic systems, construction equipment, and automotive.

SH70339 ships individually. Unit weight is approximately 9.0832 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.