8-161 BLACK FKM 90D BACK-UP RING

This back-up ring is supplied in AS568-161 black Viton® (FKM) 90 Shore A with an inside diameter of 5.487 in (139.37 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 5.693 in (144.6 mm), catalogued under part number VBU90161. It bridges the extrusion gap so the primary seal holds its shape under load.

Viton® (FKM) is specified here for very low compression set at elevated temperature and long service life in hot, chemically aggressive environments. It resists aggressive chemicals, petroleum oils and fuels, and chlorinated solvents. Published continuous service range is -15°F (-26.1°C) to 400°F (204.4°C). Verify compatibility before use with ketones and esters or low-molecular-weight organic acids.

Typical settings include chemical processing, aerospace, and oil and gas.

This item is sold individually under part number VBU90161. Nominal inside diameter is listed as 5 1/2 inch. Review your operating media and conditions against this specification before installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.