The TST246 is an AS568-246 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 4.484 in (113.89 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 4.762 in (120.95 mm). This back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
It resists steam, solvents, and strong acids and bases. PTFE (Teflon) delivers one of the lowest coefficients of friction of any solid and a very wide continuous service temperature range. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Verify compatibility before use with service requiring elastic recovery or elemental fluorine at temperature.
It sees regular use in food and beverage, chemical processing, and laboratory equipment.
TST246 ships individually. Nominal inside diameter is listed as 4 1/2 inch. Check the compound against your process media, pressure and temperature before committing to a design. For a size or compound outside the standard catalog, APG can quote from a print or sample.
description **2103-246 PTFE S/T BUP FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 4.484 inch (113.89 mm)
Actual_OD 4.762 inch (120.95 mm)
ProductCode Description O-Rings - Backup Rings