8-020 BLACK FKM 90D BACK-UP RING

APG stocks the VBU90020, an AS568-020 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 0.864 in (21.95 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.004 in (25.5 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

The material holds up against chlorinated solvents, petroleum oils and fuels, and many acids. Viton® (FKM) delivers the industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Verify compatibility before use with ketones and esters or amines.

Common environments for this compound include aerospace, high-temperature process equipment, and semiconductor equipment.

Stocked as VBU90020 and sold individually. Unit weight is approximately 0.234 g and nominal inside diameter is listed as 7/8 inch. Check the compound against your process media, pressure and temperature before committing to a design.