APG stocks the TST379SO, an AS568-379 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 10.975 in (278.77 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 11.395 in (289.43 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
As a material, PTFE (Teflon) is known for a very wide continuous service temperature range and one of the lowest coefficients of friction of any solid. This material stands up to strong acids and bases, oxidizing media, and steam. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Verify compatibility before use with service requiring elastic recovery or elemental fluorine at temperature.
Typical settings include laboratory equipment, pharmaceutical and biotech, and semiconductor fabrication.
TST379SO ships individually. Review your operating media and conditions against this specification before installation. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description 379 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.21 inch (5.33 mm)
Actual Inside Diameter 10.975 inch (278.77 mm)
Actual Outside Diameter 11.395 inch (289.43 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings