319 PTFE SOLID BACKUP RING FDA

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.