8-459 BLACK BUNA 90D BACK-UP RING

APG stocks the HB90459, an AS568-459 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 14.975 in (380.37 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 15.525 in (394.34 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

Buna-N (Nitrile) is specified here for economical choice for high-volume maintenance programs, strong abrasion and tear resistance. This material stands up to greases and lubricants, hydraulic fluids, and propane and butane. The material carries a published service range of -40°F (-40°C) to 250°F (121.1°C). Exposure to strong acids or automotive brake fluid will shorten service life.

Typical settings include fluid power, agricultural equipment, and general industrial maintenance.

This item is sold individually under part number HB90459. Unit weight is approximately 26.673 g and nominal inside diameter is listed as 15 inch. 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.