APG stocks the TST154SO, an AS568-154 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 3.737 in (94.92 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 3.943 in (100.15 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
The compound resists solvents, oxidizing media, and steam. That behavior comes from the compound itself: PTFE (Teflon) is specified for one of the lowest coefficients of friction of any solid and near-universal chemical inertness. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Verify compatibility before use with molten alkali metals or elemental fluorine at temperature.
Common environments for this compound include pharmaceutical and biotech, chemical processing, and food and beverage.
Order part number TST154SO, sold individually. Nominal inside diameter is listed as 3 3/4 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. For a size or compound outside the standard catalog, APG can quote from a print or sample.
Description 154 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 3.737 inch (94.92 mm)
Actual Outside Diameter 3.943 inch (100.15 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings