TST226 is an AS568-226 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 1.984 in (50.39 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 2.262 in (57.45 mm). In service, this back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
The material holds up against nearly all industrial chemicals, steam, and oxidizing media. PTFE (Teflon) is widely chosen for non-stick, non-contaminating surface characteristics and a very wide continuous service temperature range. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Applications involving elemental fluorine at temperature or molten alkali metals call for a different compound.
You will find this material specified across food and beverage, laboratory equipment, and aggressive-media pipelines.
Stocked as TST226 and sold individually. Nominal inside diameter is listed as 2 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Description 2103-226 PTFE S/T BUP FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 1.984 inch (50.39 mm)
Actual Outside Diameter 2.262 inch (57.45 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings