234 PTFE SOLID BACKUP RING FDA

This back-up ring is supplied in AS568-234 white PTFE (Teflon) 55 Shore D with an inside diameter of 2.984 in (75.79 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 3.262 in (82.85 mm), catalogued under part number TST234SO. 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 known for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. It resists strong acids and bases, nearly all industrial chemicals, and solvents. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or molten alkali metals.

It sees regular use in food and beverage, semiconductor fabrication, and laboratory equipment.

TST234SO ships individually. Nominal inside diameter is listed as 3 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.