Ordered as TST210, this is an AS568-210 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 0.734 in (18.64 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.012 in (25.7 mm). The back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
As a material, PTFE (Teflon) is valued for near-universal chemical inertness and a very wide continuous service temperature range. It resists oxidizing media, steam, and strong acids and bases. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C).
Common environments for this compound include chemical processing, semiconductor fabrication, and food and beverage.
Stocked as TST210 and sold individually. Check the compound against your process media, pressure and temperature before committing to a design. Not finding the exact configuration you need? APG cross-references from prints, samples and competitor part numbers.
Description 2103-210 PTFE S/T BUP FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 0.734 inch (18.64 mm)
Actual Outside Diameter 1.012 inch (25.7 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings