8-467 BLACK BUNA 90D BACK-UP RING

The HB90467 is an AS568-467 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 18.955 in (481.46 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 19.505 in (495.43 mm). This back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

The compound resists propane and butane, greases and lubricants, and hydraulic fluids. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for reliable performance in both static and dynamic service, strong abrasion and tear resistance. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Exposure to strong acids or ketones will shorten service life.

Maintenance and OEM teams specify it across general industrial maintenance, construction equipment, and fluid power.

HB90467 ships individually. Unit weight is approximately 32.773 g and nominal inside diameter is listed as 19 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.