This back-up ring is supplied in AS568-255 white PTFE (Teflon) 55 Shore D built to an inside diameter of 5.609 in (142.47 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.887 in (149.53 mm), catalogued under part number TST255SO. It extends o-ring service life by supporting the seal against extrusion under high pressure.
As a material, PTFE (Teflon) is valued for one of the lowest coefficients of friction of any solid and a very wide continuous service temperature range. The material holds up against oxidizing media, nearly all industrial chemicals, and solvents. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Verify compatibility before use with elemental fluorine at temperature or molten alkali metals.
Typical settings include semiconductor fabrication, aggressive-media pipelines, and pharmaceutical and biotech.
TST255SO ships individually. Check the compound against your process media, pressure and temperature before committing to a design.
Description 255 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 5.609 inch (142.47 mm)
Actual Outside Diameter 5.887 inch (149.53 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings