8-236 BLACK FKM 90D BACK-UP RING

The VBU90236 is an AS568-236 black Viton® (FKM) 90 Shore A Back-Up Ring supplied with an inside diameter of 3.234 in (82.14 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.512 in (89.2 mm). This back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

The compound resists aggressive chemicals, chlorinated solvents, and many acids. Viton® (FKM) offers long service life in hot, chemically aggressive environments and the industry benchmark where nitrile reaches its thermal limit. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). It is not the right choice where low-molecular-weight organic acids or ketones and esters are present.

Common environments for this compound include chemical processing, aerospace, and semiconductor equipment.

Reference part number VBU90236 when ordering; the item is sold individually. Unit weight is approximately 1.6257 g and nominal inside diameter is listed as 3 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.