APG stocks the TST319SO, an AS568-319 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 1.037 in (26.34 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.457 in (37.01 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
PTFE (Teflon) is specified here for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. This material stands up to nearly all industrial chemicals, steam, and solvents. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.
Typical settings include aggressive-media pipelines, semiconductor fabrication, and food and beverage.
Order part number TST319SO, sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
Description 319 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.21 inch (5.33 mm)
Actual Inside Diameter 1.037 inch (26.34 mm)
Actual Outside Diameter 1.457 inch (37.01 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings