393 PTFE SOLID BACKUP RING FDA

TST393SO is an AS568-393 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 23.94 in (608.08 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 24.36 in (618.74 mm). In service, this back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

PTFE (Teflon) is widely chosen for near-universal chemical inertness and one of the lowest coefficients of friction of any solid. This material stands up to solvents, oxidizing media, and strong acids and bases. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.

Typical settings include food and beverage, aggressive-media pipelines, and laboratory equipment.

Reference part number TST393SO when ordering; the item is sold individually. Nominal inside diameter is listed as 24 inch. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.