The TST173SO is an AS568-173 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 8.487 in (215.57 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 8.693 in (220.8 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
Expect good resistance to steam, strong acids and bases, and solvents. PTFE (Teflon) is valued for one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. It is not the right choice where molten alkali metals or elemental fluorine at temperature are present.
Maintenance and OEM teams specify it across laboratory equipment, semiconductor fabrication, and food and beverage.
Reference part number TST173SO when ordering; the item is sold individually. Nominal inside diameter is listed as 8 1/2 inch. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
description 173 PTFE SOLID BACKUP RING FDA
Actual_CS 0.103 inch (2.62 mm)
Actual_ID 8.487 inch (215.57 mm)
Actual_OD 8.693 inch (220.8 mm)
ProductCode Description O-Rings - Backup Rings