8-271 BLACK FKM 90D BACK-UP RING

The VBU90271 is an AS568-271 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 9.234 in (234.54 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 9.512 in (241.6 mm). This back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

As a material, Viton® (FKM) offers outstanding high-temperature capability and long service life in hot, chemically aggressive environments. The compound resists many acids, chlorinated solvents, and engine and transmission fluids. 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 automotive fuel systems, high-temperature process equipment, and semiconductor equipment.

Reference part number VBU90271 when ordering; the item is sold individually. Nominal inside diameter is listed as 9 1/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. 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.