Part number VBU90274 is an AS568-274 black Viton® (FKM) 90 Shore A Back-Up Ring built to an inside diameter of 9.984 in (253.59 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 10.262 in (260.65 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.
Viton® (FKM) is specified here for industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. This material stands up to chlorinated solvents, many acids, and petroleum oils and fuels. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C). Verify compatibility before use with hot water and steam or ketones and esters.
You will find this material specified across chemical processing, oil and gas, and high-temperature process equipment.
Reference part number VBU90274 when ordering; the item is sold individually. Nominal inside diameter is listed as 10 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
description 8-274 BLACK FKM 90D BACK-UP RING
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 9.984 inch (253.59 mm)
Actual_OD 10.262 inch (260.65 mm)
ProductCode Description O-Rings - Backup Rings