8-235 BLACK BUNA 90D BACK-UP RING

Part number HB90235 is an AS568-235 black Buna-N (Nitrile) 90 Shore A Back-Up Ring measuring an inside diameter of 3.109 in (78.97 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.387 in (86.03 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

Buna-N (Nitrile) is specified here for strong abrasion and tear resistance, most widely specified general-purpose sealing elastomer. It resists propane and butane, hydraulic fluids, and water. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Applications involving polar solvents or ozone and direct sunlight call for a different compound.

Typical settings include general industrial maintenance, agricultural equipment, and hydraulic and pneumatic systems.

Order part number HB90235, sold individually. Unit weight is approximately 1.2158 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.