Ordered as TST020SO, this is an AS568-020 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 0.864 in (21.95 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.004 in (25.5 mm). The back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
It resists solvents, steam, and strong acids and bases. PTFE (Teflon) is valued for a very wide continuous service temperature range and near-universal chemical inertness. 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 molten alkali metals.
Common environments for this compound include food and beverage, aggressive-media pipelines, and chemical processing.
This item is sold individually under part number TST020SO. Application requirements vary, so validate compatibility with your process conditions prior to installation. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Description **020 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.07 inch (1.78 mm)
Actual Inside Diameter 0.864 inch (21.95 mm)
Actual Outside Diameter 1.004 inch (25.5 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings