This back-up ring is supplied in AS568-202 white PTFE (Teflon) 55 Shore D supplied with an inside diameter of 0.234 in (5.94 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 0.512 in (13 mm), catalogued under part number TST202. It allows a standard o-ring to operate at higher pressures than it could unsupported.
PTFE (Teflon) is specified here for near-universal chemical inertness and very wide continuous service temperature range. The material holds up against nearly all industrial chemicals, strong acids and bases, and oxidizing media. Service temperature is rated from -65°F (-53.9°C) through 500°F (260°C). It should not be specified for service in molten alkali metals or service requiring elastic recovery.
Common environments for this compound include food and beverage, chemical processing, and semiconductor fabrication.
TST202 ships individually. Nominal inside diameter is listed as 1/4 inch. Check the compound against your process media, pressure and temperature before committing to a design.
Description 2103-202 PTFE S/T BUP FDA
Actual Cross Section 0.139 inch (3.53 mm)
Actual Inside Diameter 0.234 inch (5.94 mm)
Actual Outside Diameter 0.512 inch (13 mm)
Measurement System Imperial
Product Category O-Rings - Backup Rings