8-280 BLACK BUNA 90D BACK-UP RING

This back-up ring is supplied in AS568-280 black Buna-N (Nitrile) 90 Shore A with an inside diameter of 13.984 in (355.19 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 14.262 in (362.25 mm), catalogued under part number HB90280. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Buna-N (Nitrile) offers an economical choice for high-volume maintenance programs and the most widely specified general-purpose sealing elastomer. It resists greases and lubricants, hydraulic fluids, and propane and butane. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with polar solvents or ozone and direct sunlight.

Typical settings include construction equipment, agricultural equipment, and hydraulic and pneumatic systems.

Reference part number HB90280 when ordering; the item is sold individually. Unit weight is approximately 5.1088 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.