2103-445 PTFE S/T BUP FDA

This back-up ring is supplied in AS568-445 white PTFE (Teflon) 55 Shore D built to an inside diameter of 7.975 in (202.57 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 8.525 in (216.54 mm), catalogued under part number TST445. It 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) delivers one of the lowest coefficients of friction of any solid and near-universal chemical inertness. This material stands up to strong acids and bases, oxidizing media, and solvents. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C).

You will find this material specified across chemical processing, semiconductor fabrication, and food and beverage.

TST445 ships individually. Nominal inside diameter is listed as 8 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.