2103-474 PTFE S/T BUP FDA

APG stocks the TST474, an AS568-474 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 24.94 in (633.48 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 25.49 in (647.45 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

PTFE (Teflon) is specified here for very wide continuous service temperature range and near-universal chemical inertness. It resists solvents, steam, and oxidizing media. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. It is not the right choice where service requiring elastic recovery or elemental fluorine at temperature are present.

Typical settings include semiconductor fabrication, aggressive-media pipelines, and chemical processing.

This item is sold individually under part number TST474. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.