Part number TST119 is an AS568-119 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 0.924 in (23.47 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.13 in (28.7 mm). A back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
PTFE (Teflon) is specified here for near-universal chemical inertness and very wide continuous service temperature range. The compound resists oxidizing media, strong acids and bases, and solvents. 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.
It sees regular use in food and beverage, chemical processing, and laboratory equipment.
Order part number TST119, sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description 2103-119 PTFE S/T BUP FDA
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 0.924 inch (23.47 mm)
Actual Outside Diameter 1.13 inch (28.7 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings