276 PTFE SOLID BACKUP RING FDA

Part number TST276SO is an AS568-276 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 10.984 in (278.99 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 11.262 in (286.05 mm). A back-up ring 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 non-stick, non-contaminating surface characteristics. The compound resists strong acids and bases, nearly all industrial chemicals, and steam. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.

Maintenance and OEM teams specify it across aggressive-media pipelines, semiconductor fabrication, and laboratory equipment.

TST276SO ships individually. Nominal inside diameter is listed as 11 inch. Review your operating media and conditions against this specification before installation. For a size or compound outside the standard catalog, APG can quote from a print or sample.