8-270 BLACK FKM 90D BACK-UP RING

VBU90270 is an AS568-270 black Viton® (FKM) 90 Shore A Back-Up Ring supplied with an inside diameter of 8.984 in (228.19 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 9.262 in (235.25 mm). In service, this back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Viton® (FKM) is specified here for industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. The compound resists petroleum oils and fuels, many acids, and chlorinated solvents. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service.

Maintenance and OEM teams specify it across semiconductor equipment, oil and gas, and chemical processing.

VBU90270 ships individually. Nominal inside diameter is listed as 9 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.