8-236 BLACK BUNA 90D BACK-UP RING

This back-up ring is supplied in AS568-236 black Buna-N (Nitrile) 90 Shore A with an inside diameter of 3.234 in (82.14 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.512 in (89.2 mm), catalogued under part number HB90236. It allows a standard o-ring to operate at higher pressures than it could unsupported.

The compound resists propane and butane, water, and greases and lubricants. Buna-N (Nitrile) is specified for the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Applications involving ozone and direct sunlight or strong acids call for a different compound.

Typical settings include automotive, general industrial maintenance, and hydraulic and pneumatic systems.

Reference part number HB90236 when ordering; the item is sold individually. Unit weight is approximately 1.2379 g. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.