2103-252 PTFE S/T BUP FDA

Part number TST252 is an AS568-252 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 5.234 in (132.94 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.512 in (140 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

PTFE (Teflon) is valued for one of the lowest coefficients of friction of any solid and near-universal chemical inertness. It resists solvents, nearly all industrial chemicals, and oxidizing media. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). It is not the right choice where elemental fluorine at temperature or service requiring elastic recovery are present.

It sees regular use in laboratory equipment, aggressive-media pipelines, and food and beverage.

Reference part number TST252 when ordering; the item is sold individually. Nominal inside diameter is listed as 5 1/4 inch. Check the compound against your process media, pressure and temperature before committing to a design. 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.