568-168 BUNA 70 SQUARE CUT RINGS

SH70168 is an AS568-168 black Buna-N (Nitrile) 70 Shore A Square-Cut Ring with an inside diameter of 7.237 in (183.82 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 7.443 in (189.05 mm). In service, this square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.

Buna-N (Nitrile) is widely chosen for low compression set under sustained load, strong abrasion and tear resistance. It resists petroleum-based oils, greases and lubricants, and hydraulic fluids. 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 automotive brake fluid are present. The profile itself contributes a rectangular section that will not roll in the groove 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.

You will find this material specified across agricultural equipment, hydraulic and pneumatic systems, and general industrial maintenance.

Stocked as SH70168 and sold individually. Unit weight is approximately 3.786 g and nominal inside diameter is listed as 7 1/4 inch. Review your operating media and conditions against this specification before installation. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.