39 PTFE SOLID BACKUP RING FDA

APG stocks the TST039SO, an AS568-039 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 2.739 in (69.57 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 2.879 in (73.13 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.

The compound resists oxidizing media, strong acids and bases, and steam. That behavior comes from the compound itself: PTFE (Teflon) is known for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). Applications involving elemental fluorine at temperature or molten alkali metals call for a different compound.

You will find this material specified across pharmaceutical and biotech, chemical processing, and semiconductor fabrication.

TST039SO ships individually. 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.