8-164 BLACK BUNA 90D BACK-UP RING

Ordered as HB90164, this is an AS568-164 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 6.237 in (158.42 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 6.443 in (163.65 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

Expect good resistance to petroleum-based oils, many alcohols, and water. That behavior comes from the compound itself: Buna-N (Nitrile) is specified for the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Applications involving polar solvents or automotive brake fluid call for a different compound.

Typical settings include general industrial maintenance, fluid power, and automotive.

HB90164 ships individually. Unit weight is approximately 1.76 g and nominal inside diameter is listed as 6 1/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.