Ordered as TST465, this is an AS568-465 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 17.955 in (456.06 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 18.505 in (470.03 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is widely chosen for one of the lowest coefficients of friction of any solid and excellent dielectric properties. It resists oxidizing media, solvents, and nearly all industrial chemicals. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). Applications involving molten alkali metals or elemental fluorine at temperature call for a different compound.
Maintenance and OEM teams specify it across laboratory equipment, food and beverage, and pharmaceutical and biotech.
Stocked as TST465 and sold individually. Nominal inside diameter is listed as 18 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Description 2103-465 PTFE S/T BUP FDA
Actual Cross Section 0.275 inch (6.99 mm)
Actual Inside Diameter 17.955 inch (456.06 mm)
Actual Outside Diameter 18.505 inch (470.03 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings