8-135 BLACK BUNA 90D BACK-UP RING

The HB90135 is an AS568-135 black Buna-N (Nitrile) 90 Shore A Back-Up Ring supplied with an inside diameter of 1.925 in (48.9 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.131 in (54.13 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

Buna-N (Nitrile) is valued for low compression set under sustained load and the most widely specified general-purpose sealing elastomer. The compound resists water, propane and butane, and greases and lubricants. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in automotive brake fluid or ketones.

It sees regular use in construction equipment, general industrial maintenance, and hydraulic and pneumatic systems.

Stocked as HB90135 and sold individually. Unit weight is approximately 0.584 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.