APG stocks the TST261SO, an AS568-261 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 6.734 in (171.04 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 7.012 in (178.1 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
Expect good resistance to nearly all industrial chemicals, solvents, and steam. PTFE (Teflon) delivers near-universal chemical inertness and excellent dielectric properties. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Applications involving molten alkali metals or elemental fluorine at temperature call for a different compound.
Typical settings include aggressive-media pipelines, chemical processing, and laboratory equipment.
Stocked as TST261SO and sold individually. 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 261 PTFE SOLID BACKUP RING FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 6.734 inch (171.04 mm)
Actual_OD 7.012 inch (178.1 mm)
ProductCode Description O-Rings - Backup Rings