568-046 BUNA 70 SQUARE CUT RINGS

This square-cut ring is supplied in AS568-046 black Buna-N (Nitrile) 70 Shore A measuring an inside diameter of 4.239 in (107.67 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 4.379 in (111.23 mm), catalogued under part number SH70046. It resists the spiral failure that affects round rings on long reciprocating strokes.

The compound resists greases and lubricants, petroleum-based oils, and propane and butane. Buna-N (Nitrile) is widely chosen for the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in strong acids or ozone and direct sunlight. The profile itself contributes a flat contact band that spreads sealing load across a wider area 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.

Common environments for this compound include automotive, agricultural equipment, and fluid power.

Reference part number SH70046 when ordering; the item is sold individually. Unit weight is approximately 1.059 g and nominal inside diameter is listed as 4 1/4 inch. 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.