The TST117SO is an AS568-117 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 0.799 in (20.29 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.005 in (25.53 mm). This back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
As a material, PTFE (Teflon) offers near-universal chemical inertness and non-stick, non-contaminating surface characteristics. This material stands up to oxidizing media, nearly all industrial chemicals, and solvents. 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 molten alkali metals or elemental fluorine at temperature.
You will find this material specified across pharmaceutical and biotech, semiconductor fabrication, and chemical processing.
Reference part number TST117SO when ordering; the item is sold individually. Review your operating media and conditions against this specification before installation.
Description 117 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 0.799 inch (20.29 mm)
Actual Outside Diameter 1.005 inch (25.53 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings