161 PTFE SOLID BACKUP RING FDA

Ordered as TST161SO, this is an AS568-161 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 5.487 in (139.37 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 5.693 in (144.6 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

The compound resists strong acids and bases, oxidizing media, and solvents. PTFE (Teflon) offers near-universal chemical inertness and one of the lowest coefficients of friction of any solid. 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.

Maintenance and OEM teams specify it across pharmaceutical and biotech, chemical processing, and semiconductor fabrication.

This item is sold individually under part number TST161SO. Nominal inside diameter is listed as 5 1/2 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.