APG stocks the TST026SO, an AS568-026 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 1.239 in (31.47 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.379 in (35.03 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
Expect good resistance to oxidizing media, steam, and solvents. That behavior comes from the compound itself: PTFE (Teflon) is valued for near-universal chemical inertness and non-stick, non-contaminating surface characteristics. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.
Maintenance and OEM teams specify it across chemical processing, aggressive-media pipelines, and laboratory equipment.
Stocked as TST026SO and sold individually. Check the compound against your process media, pressure and temperature before committing to a design.
description 026 PTFE SOLID BACKUP RING FDA
Actual_CS 0.07 inch (1.78 mm)
Actual_ID 1.239 inch (31.47 mm)
Actual_OD 1.379 inch (35.03 mm)
ProductCode Description O-Rings - Backup Rings