8-361 BLACK BUNA 90D BACK-UP RING

Ordered as HB90361, this is an AS568-361 black Buna-N (Nitrile) 90 Shore A Back-Up Ring built to an inside diameter of 5.975 in (151.77 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 6.395 in (162.43 mm). The back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

Buna-N (Nitrile) is known for the most widely specified general-purpose sealing elastomer, reliable performance in both static and dynamic service. Expect good resistance to propane and butane, greases and lubricants, and petroleum-based oils. Service temperature is rated from -40°F (-40°C) through 250°F (121.1°C).

You will find this material specified across fluid power, hydraulic and pneumatic systems, and construction equipment.

HB90361 ships individually. Unit weight is approximately 5.1015 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.