8-445 BLACK FKM 90D BACK-UP RING

Ordered as VBU90445, this is an AS568-445 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 7.975 in (202.57 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 8.525 in (216.54 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

The material holds up against aromatic hydrocarbons, aggressive chemicals, and petroleum oils and fuels. Viton® (FKM) is specified for outstanding high-temperature capability and very low compression set at elevated temperature. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). Exposure to ketones and esters or hot water and steam will shorten service life.

Common environments for this compound include semiconductor equipment, automotive fuel systems, and chemical processing.

VBU90445 ships individually. Nominal inside diameter is listed as 8 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.