APG stocks the TST027SO, an AS568-027 white PTFE (Teflon) 55 Shore D Back-Up Ring built to an inside diameter of 1.301 in (33.05 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 1.441 in (36.6 mm). A back-up ring extends o-ring service life by supporting the seal against extrusion under high pressure.
PTFE (Teflon) is known for non-stick, non-contaminating surface characteristics and near-universal chemical inertness. It resists strong acids and bases, steam, and oxidizing media. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C). Applications involving elemental fluorine at temperature or molten alkali metals call for a different compound.
You will find this material specified across pharmaceutical and biotech, laboratory equipment, and aggressive-media pipelines.
Order part number TST027SO, sold individually. Nominal inside diameter is listed as 1 5/16 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application.
Description *027 TEFLON SOLID BACKUPS FDA
Actual Cross Section 0.07 inch (1.78 mm)
Actual Inside Diameter 1.301 inch (33.05 mm)
Actual Outside Diameter 1.441 inch (36.6 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings