2103-253 PTFE S/T BUP FDA

Part number TST253 is an AS568-253 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 5.359 in (136.12 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.637 in (143.18 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

As a material, PTFE (Teflon) is valued for a very wide continuous service temperature range and one of the lowest coefficients of friction of any solid. The material holds up against solvents, steam, and strong acids and bases. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Verify compatibility before use with service requiring elastic recovery or elemental fluorine at temperature.

Maintenance and OEM teams specify it across food and beverage, chemical processing, and aggressive-media pipelines.

This item is sold individually under part number TST253. Nominal inside diameter is listed as 5 3/8 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.