Ordered as VBU90164, this is an AS568-164 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 6.237 in (158.42 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 6.443 in (163.65 mm). The back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
The material holds up against petroleum oils and fuels, chlorinated solvents, and aggressive chemicals. Viton® (FKM) is specified for excellent resistance to compression set and permeation, long service life in hot, chemically aggressive environments. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C).
You will find this material specified across semiconductor equipment, automotive fuel systems, and aerospace.
Order part number VBU90164, sold individually. Nominal inside diameter is listed as 6 1/4 inch. 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 8-164 BLACK FKM 90D BACK-UP RING
Actual_CS 0.103 inch (2.62 mm)
Actual_ID 6.237 inch (158.42 mm)
Actual_OD 6.443 inch (163.65 mm)
ProductCode Description O-Rings - Backup Rings