8-316 BLACK BUNA 90D BACK-UP RING

This back-up ring is supplied in AS568-316 black Buna-N (Nitrile) 90 Shore A measuring an inside diameter of 0.85 in (21.59 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.27 in (32.26 mm), catalogued under part number HB90316. It extends o-ring service life by supporting the seal against extrusion under high pressure.

This material stands up to hydraulic fluids, water, and many alcohols. That behavior comes from the compound itself: Buna-N (Nitrile) offers low compression set under sustained load, reliable performance in both static and dynamic service. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Exposure to automotive brake fluid or ozone and direct sunlight will shorten service life.

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

This item is sold individually under part number HB90316. Unit weight is approximately 0.891 g. Review your operating media and conditions against this specification before installation.