2103-338 PTFE S/T BUP FDA

Part number TST338 is an AS568-338 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 3.1 in (78.74 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.52 in (89.41 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

PTFE (Teflon) is specified here for one of the lowest coefficients of friction of any solid and excellent dielectric properties. The material holds up against strong acids and bases, oxidizing media, and solvents. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in service requiring elastic recovery or elemental fluorine at temperature.

Maintenance and OEM teams specify it across food and beverage, laboratory equipment, and aggressive-media pipelines.

This item is sold individually under part number TST338. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.