8-381 BLACK FKM 90D BACK-UP RING

The VBU90381 is an AS568-381 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 11.975 in (304.17 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 12.395 in (314.83 mm). This back-up ring bridges the extrusion gap so the primary seal holds its shape under load.

As a material, Viton® (FKM) is specified for outstanding high-temperature capability, excellent resistance to compression set and permeation. The compound resists aggressive chemicals, aromatic hydrocarbons, and chlorinated solvents. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). Applications involving low-molecular-weight organic acids or ketones and esters call for a different compound.

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

This item is sold individually under part number VBU90381. As always, verify media compatibility and operating conditions against the requirements of your specific application. For a size or compound outside the standard catalog, APG can quote from a print or sample.