8-363 BLACK FKM 90D BACK-UP RING

This back-up ring is supplied in AS568-363 black Viton® (FKM) 90 Shore A built to an inside diameter of 6.475 in (164.47 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 6.895 in (175.13 mm), catalogued under part number VBU90363. It extends o-ring service life by supporting the seal against extrusion under high pressure.

As a material, Viton® (FKM) is known for the industry benchmark where nitrile reaches its thermal limit and very low compression set at elevated temperature. It resists aromatic hydrocarbons, chlorinated solvents, and many acids. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). Verify compatibility before use with low-molecular-weight organic acids or amines.

It sees regular use in chemical processing, aerospace, and automotive fuel systems.

VBU90363 ships individually. Unit weight is approximately 7.369 g. Application requirements vary, so validate compatibility with your process conditions prior to installation. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.