8-140 BLACK BUNA 90D BACK-UP RING

Part number HB90140 is an AS568-140 black Buna-N (Nitrile) 90 Shore A Back-Up Ring supplied with an inside diameter of 2.237 in (56.82 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.443 in (62.05 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

The compound resists petroleum-based oils, hydraulic fluids, and greases and lubricants. Buna-N (Nitrile) offers an economical choice for high-volume maintenance programs and low compression set under sustained load. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Verify compatibility before use with automotive brake fluid or ozone and direct sunlight.

Typical settings include construction equipment, hydraulic and pneumatic systems, and fluid power.

Stocked as HB90140 and sold individually. Unit weight is approximately 0.668 g and nominal inside diameter is listed as 2 1/4 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation.