Part number TST352SO is an AS568-352 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 4.85 in (123.19 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 5.27 in (133.86 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is specified for non-stick, non-contaminating surface characteristics and excellent dielectric properties. The compound resists oxidizing media, solvents, and steam. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). It should not be specified for service in service requiring elastic recovery or elemental fluorine at temperature.
It sees regular use in aggressive-media pipelines, chemical processing, and laboratory equipment.
Reference part number TST352SO when ordering; the item is sold individually. Nominal inside diameter is listed as 4 7/8 inch. Application requirements vary, so validate compatibility with your process conditions prior to installation. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
description 352 PTFE SOLID BACKUP RING FDA
Actual_CS 0.21 inch (5.33 mm)
Actual_ID 4.85 inch (123.19 mm)
Actual_OD 5.27 inch (133.86 mm)
ProductCode Description O-Rings - Backup Rings