Part number VBU90324 is an AS568-324 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 1.35 in (34.29 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.77 in (44.96 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
This material stands up to many acids, aromatic hydrocarbons, and engine and transmission fluids. Viton® (FKM) offers 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). It is not the right choice where amines or hot water and steam are present.
Common environments for this compound include semiconductor equipment, oil and gas, and automotive fuel systems.
Reference part number VBU90324 when ordering; the item is sold individually. Nominal inside diameter is listed as 1 3/8 inch. Review your operating media and conditions against this specification before installation.
description 8-324 BLACK FKM 90D BACK-UP RING
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 1.35 inch (34.29 mm)
Actual_OD 1.77 inch (44.96 mm)
ProductCode Description O-Rings - Backup Rings