8-472 BLACK BUNA 90D BACK-UP RING

The HB90472 is an AS568-472 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 22.94 in (582.68 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 23.49 in (596.65 mm). This back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Expect good resistance to petroleum-based oils, water, and propane and butane. That behavior comes from the compound itself: Buna-N (Nitrile) is widely chosen for reliable performance in both static and dynamic service, an economical choice for high-volume maintenance programs. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with strong acids or polar solvents.

Maintenance and OEM teams specify it across agricultural equipment, fluid power, and hydraulic and pneumatic systems.

HB90472 ships individually. Unit weight is approximately 39.795 g and nominal inside diameter is listed as 23 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation.