TST118SO is an AS568-118 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 0.862 in (21.89 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.068 in (27.13 mm). In service, this back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
PTFE (Teflon) is known for near-universal chemical inertness and one of the lowest coefficients of friction of any solid. The material holds up against solvents, oxidizing media, and nearly all industrial chemicals. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It is not the right choice where elemental fluorine at temperature or molten alkali metals are present.
You will find this material specified across chemical processing, aggressive-media pipelines, and food and beverage.
Order part number TST118SO, sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Description 118 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 0.862 inch (21.89 mm)
Actual Outside Diameter 1.068 inch (27.13 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings