The TST137SO is an AS568-137 white PTFE (Teflon) 55 Shore D Back-Up Ring measuring an inside diameter of 2.05 in (52.07 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 2.256 in (57.3 mm). This back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
As a material, PTFE (Teflon) is widely chosen for near-universal chemical inertness and a very wide continuous service temperature range. Expect good resistance to steam, nearly all industrial chemicals, and solvents. Published continuous service range is -65°F (-53.9°C) to 500°F (260°C).
It sees regular use in aggressive-media pipelines, semiconductor fabrication, and chemical processing.
Stocked as TST137SO and sold individually. Nominal inside diameter is listed as 2 1/16 inch. Review your operating media and conditions against this specification before installation.
Description 137 PTFE SOLID BACKUP RING FDA
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 2.05 inch (52.07 mm)
Actual Outside Diameter 2.256 inch (57.3 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings