8-140 BLACK FKM 90D BACK-UP RING

This back-up ring is supplied in AS568-140 black Viton® (FKM) 90 Shore A built to an inside diameter of 2.237 in (56.82 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.443 in (62.05 mm), catalogued under part number VBU90140. It extends o-ring service life by supporting the seal against extrusion under high pressure.

This material stands up to aggressive chemicals, engine and transmission fluids, and aromatic hydrocarbons. That behavior comes from the compound itself: Viton® (FKM) is widely chosen for the industry benchmark where nitrile reaches its thermal limit and outstanding high-temperature capability. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C).

Maintenance and OEM teams specify it across chemical processing, aerospace, and automotive fuel systems.

Order part number VBU90140, sold individually. Unit weight is approximately 0.8917 g. As always, verify media compatibility and operating conditions against the requirements of your specific application. For a size or compound outside the standard catalog, APG can quote from a print or sample.