568-905 BUNA 70 SQUARE CUT RINGS

This square-cut ring is supplied in AS568-905 black Buna-N (Nitrile) 70 Shore A supplied with an inside diameter of 0.414 in (10.52 mm), a cross section of 0.072 in (1.83 mm), and an outside diameter of 0.558 in (14.17 mm), catalogued under part number SH70905. It seals with a broad flat contact band instead of the line contact of a round-section ring.

Buna-N (Nitrile) is specified here for most widely specified general-purpose sealing elastomer and economical choice for high-volume maintenance programs. It resists petroleum-based oils, many alcohols, and water. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Exposure to ketones or strong acids will shorten service life. The profile itself contributes simple lathe-cut manufacture at low tooling cost 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 fluid power, construction equipment, and general industrial maintenance.

SH70905 ships individually. Nominal inside diameter is listed as 5/16 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.