TST344SO is an AS568-344 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 3.85 in (97.79 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 4.27 in (108.46 mm). In service, this back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
The material holds up against strong acids and bases, nearly all industrial chemicals, and oxidizing media. PTFE (Teflon) is specified for non-stick, non-contaminating surface characteristics and one of the lowest coefficients of friction of any solid. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.
Typical settings include pharmaceutical and biotech, semiconductor fabrication, and chemical processing.
Order part number TST344SO, sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
description *344 PTFE SOLID BACKUP RING FDA
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 3.85 inch (97.79 mm)
Actual_OD 4.27 inch (108.46 mm)
ProductCode Description O-Rings - Backup Rings