371 PTFE SOLID BACKUP RING FDA

APG stocks the TST371SO, an AS568-371 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 8.475 in (215.27 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 8.895 in (225.93 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

As a material, PTFE (Teflon) is valued for a very wide continuous service temperature range and excellent dielectric properties. The compound resists solvents, strong acids and bases, and steam. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in service requiring elastic recovery or molten alkali metals.

Common environments for this compound include food and beverage, laboratory equipment, and chemical processing.

Stocked as TST371SO and sold individually. Nominal inside diameter is listed as 8 1/2 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation.