321 PTFE SOLID BACKUP RING FDA

Part number TST321SO is an AS568-321 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 1.162 in (29.51 mm), a cross section of 0.21 in (5.33 mm), and an outside diameter of 1.582 in (40.18 mm). A back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

PTFE (Teflon) is specified here for non-stick, non-contaminating surface characteristics and very wide continuous service temperature range. It resists nearly all industrial chemicals, solvents, and strong acids and bases. 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.

Maintenance and OEM teams specify it across pharmaceutical and biotech, chemical processing, and aggressive-media pipelines.

Reference part number TST321SO when ordering; the item is sold individually. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing.