2103-331 PTFE S/T BUP FDA

The TST331 is an AS568-331 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 2.225 in (56.52 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 2.645 in (67.18 mm). This back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Expect good resistance to nearly all industrial chemicals, strong acids and bases, and solvents. That behavior comes from the compound itself: PTFE (Teflon) is widely chosen for non-stick, non-contaminating surface characteristics and excellent dielectric properties. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Exposure to molten alkali metals or elemental fluorine at temperature will shorten service life.

Maintenance and OEM teams specify it across chemical processing, food and beverage, and laboratory equipment.

This item is sold individually under part number TST331. Nominal inside diameter is listed as 2 1/4 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application.