This back-up ring is supplied in AS568-341 white PTFE (Teflon) 55 Shore D built to an inside diameter of 3.475 in (88.27 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 3.895 in (98.93 mm), catalogued under part number TST341SO. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
PTFE (Teflon) is specified here for very wide continuous service temperature range and one of the lowest coefficients of friction of any solid. Expect good resistance to nearly all industrial chemicals, oxidizing media, and steam. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). Applications involving service requiring elastic recovery or elemental fluorine at temperature call for a different compound.
It sees regular use in food and beverage, pharmaceutical and biotech, and laboratory equipment.
TST341SO 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 341 PTFE SOLID BACKUP RING FDA
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 3.475 inch (88.27 mm)
Actual_OD 3.895 inch (98.93 mm)
ProductCode Description O-Rings - Backup Rings