The VBU90446 is an AS568-446 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 8.475 in (215.27 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 9.025 in (229.24 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
This material stands up to many acids, petroleum oils and fuels, and chlorinated solvents. That behavior comes from the compound itself: Viton® (FKM) is specified for outstanding high-temperature capability and very low compression set at elevated temperature. Rated temperature range runs from -15°F (-26.1°C) to 400°F (204.4°C) in continuous service. Exposure to amines or ketones and esters will shorten service life.
Maintenance and OEM teams specify it across automotive fuel systems, oil and gas, and chemical processing.
VBU90446 ships individually. Nominal inside diameter is listed as 8 1/2 inch. Check the compound against your process media, pressure and temperature before committing to a design.
description 8-446 BLACK FKM 90D BACK-UP RING
Actual_CS 0.275 inch (6.99 mm)
Actual_ID 8.475 inch (215.27 mm)
Actual_OD 9.025 inch (229.24 mm)
ProductCode Description O-Rings - Backup Rings