This back-up ring is supplied in AS568-229 white PTFE (Teflon) 55 Shore D built to an inside diameter of 2.359 in (59.92 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 2.637 in (66.98 mm), catalogued under part number TST229. It allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is specified here for near-universal chemical inertness and excellent dielectric properties. This material stands up to steam, strong acids and bases, and solvents. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). Applications involving service requiring elastic recovery or elemental fluorine at temperature call for a different compound.
Typical settings include food and beverage, laboratory equipment, and semiconductor fabrication.
Reference part number TST229 when ordering; the item is sold individually. Nominal inside diameter is listed as 2 3/8 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
description 2103-229 PTFE S/T BUP FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 2.359 inch (59.92 mm)
Actual_OD 2.637 inch (66.98 mm)
ProductCode Description O-Rings - Backup Rings