8-047 BLACK FKM 90D BACK-UP RING

VBU90047 is an AS568-047 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 4.489 in (114.02 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 4.629 in (117.58 mm). In service, this back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

As a material, Viton® (FKM) is known for very low compression set at elevated temperature and the industry benchmark where nitrile reaches its thermal limit. This material stands up to engine and transmission fluids, petroleum oils and fuels, and chlorinated solvents. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C).

Typical settings include semiconductor equipment, chemical processing, and high-temperature process equipment.

Reference part number VBU90047 when ordering; the item is sold individually. Nominal inside diameter is listed as 4 1/2 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.