This back-up ring is supplied in AS568-323 white PTFE (Teflon) 55 Shore D with an inside diameter of 1.287 in (32.69 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.707 in (43.36 mm), catalogued under part number TST323. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
As a material, PTFE (Teflon) is widely chosen for one of the lowest coefficients of friction of any solid and near-universal chemical inertness. It resists steam, solvents, and nearly all industrial chemicals. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in molten alkali metals or elemental fluorine at temperature.
You will find this material specified across aggressive-media pipelines, pharmaceutical and biotech, and chemical processing.
TST323 ships individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
description 2103-323 PTFE S/T BUP FDA
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 1.287 inch (32.69 mm)
Actual_OD 1.707 inch (43.36 mm)
ProductCode Description O-Rings - Backup Rings