436 PTFE SOLID BACKUP RING FDA

This back-up ring is supplied in AS568-436 white PTFE (Teflon) 55 Shore D measuring an inside diameter of 5.85 in (148.59 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.4 in (162.56 mm), catalogued under part number TST436SO. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

As a material, PTFE (Teflon) is widely chosen for near-universal chemical inertness and one of the lowest coefficients of friction of any solid. It resists steam, nearly all industrial chemicals, and oxidizing media. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). It is not the right choice where service requiring elastic recovery or elemental fluorine at temperature are present.

Typical settings include aggressive-media pipelines, pharmaceutical and biotech, and semiconductor fabrication.

Stocked as TST436SO and sold individually. Nominal inside diameter is listed as 5 7/8 inch. 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.