8-469 BLACK BUNA 90D BACK-UP RING

The HB90469 is an AS568-469 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 19.955 in (506.86 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 20.505 in (520.83 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.

Buna-N (Nitrile) is specified here for reliable performance in both static and dynamic service, most widely specified general-purpose sealing elastomer. This material stands up to many alcohols, water, and propane and butane. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in ozone and direct sunlight or automotive brake fluid.

Common environments for this compound include agricultural equipment, construction equipment, and general industrial maintenance.

Reference part number HB90469 when ordering; the item is sold individually. Unit weight is approximately 34.644 g and nominal inside diameter is listed as 20 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation.