Ordered as TST217, this is an AS568-217 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 1.171 in (29.74 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.449 in (36.8 mm). The back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is valued for a very wide continuous service temperature range and one of the lowest coefficients of friction of any solid. The compound resists nearly all industrial chemicals, solvents, and oxidizing media. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in elemental fluorine at temperature or service requiring elastic recovery.
Typical settings include food and beverage, pharmaceutical and biotech, and laboratory equipment.
Order part number TST217, sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
description 2103-217 PTFE S/T BUP FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 1.171 inch (29.74 mm)
Actual_OD 1.449 inch (36.8 mm)
ProductCode Description O-Rings - Backup Rings