Part number VBU90326 is an AS568-326 black Viton® (FKM) 90 Shore A Back-Up Ring measuring an inside diameter of 1.6 in (40.64 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 2.02 in (51.31 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
The material holds up against petroleum oils and fuels, aggressive chemicals, and engine and transmission fluids. That behavior comes from the compound itself: Viton® (FKM) is known for outstanding high-temperature capability and very low compression set at elevated temperature. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C).
You will find this material specified across aerospace, automotive fuel systems, and high-temperature process equipment.
Order part number VBU90326, sold individually. Unit weight is approximately 2.3 g and nominal inside diameter is listed as 1 5/8 inch. Check the compound against your process media, pressure and temperature before committing to a design.
description 8-326 BLACK FKM 90D BACK-UP RING
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 1.6 inch (40.64 mm)
Actual_OD 2.02 inch (51.31 mm)
ProductCode Description O-Rings - Backup Rings