Ordered as VBU90227, this is an AS568-227 black Viton® (FKM) 90 Shore A Back-Up Ring with an inside diameter of 2.109 in (53.57 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 2.387 in (60.63 mm). The back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
The material holds up against many acids, aromatic hydrocarbons, and chlorinated solvents. That behavior comes from the compound itself: Viton® (FKM) delivers very low compression set at elevated temperature and outstanding high-temperature capability. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C).
Maintenance and OEM teams specify it across chemical processing, oil and gas, and aerospace.
Stocked as VBU90227 and sold individually. Unit weight is approximately 1.0959 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
description 8-227 BLACK FKM 90D BACK-UP RING
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 2.109 inch (53.57 mm)
Actual_OD 2.387 inch (60.63 mm)
ProductCode Description O-Rings - Backup Rings