8-319 BLACK FKM 90D BACK-UP RING

VBU90319 is an AS568-319 black Viton® (FKM) 90 Shore A Back-Up Ring supplied with an inside diameter of 1.037 in (26.34 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.457 in (37.01 mm). In service, this back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

This material stands up to aromatic hydrocarbons, engine and transmission fluids, and aggressive chemicals. That behavior comes from the compound itself: Viton® (FKM) is known for long service life in hot, chemically aggressive environments and very low compression set at elevated temperature. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in amines or ketones and esters.

Maintenance and OEM teams specify it across semiconductor equipment, high-temperature process equipment, and oil and gas.

This item is sold individually under part number VBU90319. Nominal inside diameter is listed as 1 1/16 inch. Review your operating media and conditions against this specification before installation.