This back-up ring is supplied in AS568-174 white PTFE (Teflon) 55 Shore D with an inside diameter of 8.737 in (221.92 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 8.943 in (227.15 mm), catalogued under part number TST174. It allows a standard o-ring to operate at higher pressures than it could unsupported.
Expect good resistance to solvents, oxidizing media, and nearly all industrial chemicals. That behavior comes from the compound itself: PTFE (Teflon) delivers excellent dielectric properties and a very wide continuous service temperature range. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Exposure to molten alkali metals or service requiring elastic recovery will shorten service life.
You will find this material specified across chemical processing, pharmaceutical and biotech, and aggressive-media pipelines.
Stocked as TST174 and sold individually. 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.
description 2103-174 PTFE S/T BUP FDA
Actual_CS 0.103 inch (2.62 mm)
Actual_ID 8.737 inch (221.92 mm)
Actual_OD 8.943 inch (227.15 mm)
ProductCode Description O-Rings - Backup Rings