8-019 BLACK FKM 90D BACK-UP RING

Ordered as VBU90019, this is an AS568-019 black Viton® (FKM) 90 Shore A Back-Up Ring supplied with an inside diameter of 0.801 in (20.35 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 0.941 in (23.9 mm). The 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 excellent resistance to compression set and permeation, long service life in hot, chemically aggressive environments. The compound resists aromatic hydrocarbons, petroleum oils and fuels, and engine and transmission fluids. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C). Applications involving ketones and esters or low-molecular-weight organic acids call for a different compound.

You will find this material specified across chemical processing, high-temperature process equipment, and semiconductor equipment.

Order part number VBU90019, sold individually. Unit weight is approximately 0.2375 g. Review your operating media and conditions against this specification before installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.