8-312 BLACK BUNA 90D BACK-UP RING

This back-up ring is supplied in AS568-312 black Buna-N (Nitrile) 90 Shore A supplied with an inside diameter of 0.6 in (15.24 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.02 in (25.91 mm), catalogued under part number HB90312. It extends o-ring service life by supporting the seal against extrusion under high pressure.

Buna-N (Nitrile) is valued for strong abrasion and tear resistance, reliable performance in both static and dynamic service. The compound resists hydraulic fluids, greases and lubricants, and water. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Applications involving polar solvents or automotive brake fluid call for a different compound.

You will find this material specified across construction equipment, general industrial maintenance, and hydraulic and pneumatic systems.

This item is sold individually under part number HB90312. Unit weight is approximately 0.678 g and nominal inside diameter is listed as 5/8 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.