8-457 BLACK FKM 90D BACK-UP RING

APG stocks the VBU90457, an AS568-457 black Viton® (FKM) 90 Shore A Back-Up Ring built to an inside diameter of 13.975 in (354.97 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 14.525 in (368.94 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

The material holds up against chlorinated solvents, aggressive chemicals, and engine and transmission fluids. That behavior comes from the compound itself: Viton® (FKM) is specified for excellent resistance to compression set and permeation, very low compression set at elevated temperature. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). It should not be specified for service in ketones and esters or hot water and steam.

You will find this material specified across oil and gas, semiconductor equipment, and aerospace.

VBU90457 ships individually. Application requirements vary, so validate compatibility with your process conditions prior to installation. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.