The TST279SO is an AS568-279 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 12.984 in (329.79 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 13.262 in (336.85 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is known for non-stick, non-contaminating surface characteristics and excellent dielectric properties. Expect good resistance to steam, oxidizing media, and strong acids and bases. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). Exposure to elemental fluorine at temperature or molten alkali metals will shorten service life.
It sees regular use in aggressive-media pipelines, pharmaceutical and biotech, and chemical processing.
Stocked as TST279SO and sold individually. Application requirements vary, so validate compatibility with your process conditions prior to installation.
Description 279 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 12.984 inch (329.79 mm)
Actual Outside Diameter 13.262 inch (336.85 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings