8-167 BLACK BUNA 90D BACK-UP RING

APG stocks the HB90167, an AS568-167 black Buna-N (Nitrile) 90 Shore A Back-Up Ring with an inside diameter of 6.987 in (177.47 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 7.193 in (182.7 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

Buna-N (Nitrile) delivers an economical choice for high-volume maintenance programs, strong abrasion and tear resistance. This material stands up to water, petroleum-based oils, and hydraulic fluids. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. It is not the right choice where automotive brake fluid or ketones are present.

Maintenance and OEM teams specify it across fluid power, hydraulic and pneumatic systems, and automotive.

This item is sold individually under part number HB90167. Nominal inside diameter is listed as 7 inch. Check the compound against your process media, pressure and temperature before committing to a design. 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.