Ordered as TST029, this is an AS568-029 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 1.489 in (37.82 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.629 in (41.38 mm). The back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
PTFE (Teflon) is specified for excellent dielectric properties and one of the lowest coefficients of friction of any solid. The material holds up against steam, nearly all industrial chemicals, and solvents. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. It should not be specified for service in elemental fluorine at temperature or molten alkali metals.
You will find this material specified across laboratory equipment, pharmaceutical and biotech, and semiconductor fabrication.
Stocked as TST029 and sold individually. Check the compound against your process media, pressure and temperature before committing to a design. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Description *2103-029 PTFE S/T BUP FDA
Actual Cross Section 0.07 inch (1.78 mm)
Actual Inside Diameter 1.489 inch (37.82 mm)
Actual Outside Diameter 1.629 inch (41.38 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings