8-373 BLACK BUNA 90D BACK-UP RING

HB90373 is an AS568-373 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 8.975 in (227.97 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 9.395 in (238.63 mm). In service, this back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

Buna-N (Nitrile) offers low compression set under sustained load, strong abrasion and tear resistance. The material holds up against petroleum-based oils, many alcohols, and hydraulic fluids. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Exposure to ketones or ozone and direct sunlight will shorten service life.

It sees regular use in hydraulic and pneumatic systems, fluid power, and construction equipment.

Stocked as HB90373 and sold individually. Unit weight is approximately 7.675 g. Check the compound against your process media, pressure and temperature before committing to a design.