8-233 BLACK FKM 90D BACK-UP RING

Part number VBU90233 is an AS568-233 black Viton® (FKM) 90 Shore A Back-Up Ring built to an inside diameter of 2.859 in (72.62 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.137 in (79.68 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

This material stands up to aromatic hydrocarbons, many acids, and aggressive chemicals. Viton® (FKM) is widely chosen for long service life in hot, chemically aggressive environments, excellent resistance to compression set and permeation. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C). Applications involving ketones and esters or amines call for a different compound.

Maintenance and OEM teams specify it across aerospace, high-temperature process equipment, and semiconductor equipment.

VBU90233 ships individually. Unit weight is approximately 1.4626 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.