Part number TST017 is an AS568-017 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 0.676 in (17.17 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 0.816 in (20.73 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.
As a material, PTFE (Teflon) delivers one of the lowest coefficients of friction of any solid and non-stick, non-contaminating surface characteristics. Expect good resistance to strong acids and bases, solvents, and steam. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C).
You will find this material specified across aggressive-media pipelines, chemical processing, and pharmaceutical and biotech.
Reference part number TST017 when ordering; the item is sold individually. As always, verify media compatibility and operating conditions against the requirements of your specific application.
description 2103-017 PTFE S/T BUP FDA
Actual_CS 0.07 inch (1.78 mm)
Actual_ID 0.676 inch (17.17 mm)
Actual_OD 0.816 inch (20.73 )
ProductCode Description O-Rings - Backup Rings