8-381 BLACK BUNA 90D BACK-UP RING

This back-up ring is supplied in AS568-381 black Buna-N (Nitrile) 90 Shore A built to an inside diameter of 11.975 in (304.17 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 12.395 in (314.83 mm), catalogued under part number HB90381. It allows a standard o-ring to operate at higher pressures than it could unsupported.

Buna-N (Nitrile) is specified here for most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. The material holds up against water, propane and butane, and greases and lubricants. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C).

You will find this material specified across fluid power, general industrial maintenance, and agricultural equipment.

This item is sold individually under part number HB90381. Unit weight is approximately 10.0342 g and nominal inside diameter is listed as 12 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.