8-376 BLACK BUNA 90D BACK-UP RING

Part number HB90376 is an AS568-376 black Buna-N (Nitrile) 90 Shore A Back-Up Ring supplied with an inside diameter of 9.725 in (247.02 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 10.145 in (257.68 mm). A 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 strong abrasion and tear resistance, reliable performance in both static and dynamic service. The material holds up against water, propane and butane, and many alcohols. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ozone and direct sunlight or strong acids are present.

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

Order part number HB90376, sold individually. Unit weight is approximately 8.182 g and nominal inside diameter is listed as 9 3/4 inch. Review your operating media and conditions against this specification before installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.