8-317 BLACK BUNA 90D BACK-UP RING

The HB90317 is an AS568-317 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 0.912 in (23.16 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.332 in (33.83 mm). This back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

This material stands up to hydraulic fluids, propane and butane, and greases and lubricants. Buna-N (Nitrile) is widely chosen for the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It is not the right choice where ozone and direct sunlight or polar solvents are present.

Typical settings include automotive, agricultural equipment, and general industrial maintenance.

This item is sold individually under part number HB90317. Unit weight is approximately 0.959 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.