APG stocks the TST050, an AS568-050 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 5.239 in (133.07 mm), a cross section of 0.07 in (1.78 mm), and an outside diameter of 5.379 in (136.63 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.
This material stands up to solvents, nearly all industrial chemicals, and steam. PTFE (Teflon) delivers non-stick, non-contaminating surface characteristics and a very wide continuous service temperature range. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It is not the right choice where molten alkali metals or service requiring elastic recovery are present.
Common environments for this compound include laboratory equipment, semiconductor fabrication, and food and beverage.
Reference part number TST050 when ordering; the item is sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.
Description 2103-050 PTFE S/T BUP FDA
Actual Cross Section 0.07 inch (1.78 mm)
Actual Inside Diameter 5.239 inch (133.07 mm)
Actual Outside Diameter 5.379 inch (136.63 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings