157 PTFE SOLID BACKUP RING FDA

The TST157SO is an AS568-157 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 4.487 in (113.97 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 4.693 in (119.2 mm). This back-up ring allows a standard o-ring to operate at higher pressures than it could unsupported.

The material holds up against solvents, nearly all industrial chemicals, and strong acids and bases. PTFE (Teflon) offers non-stick, non-contaminating surface characteristics and a very wide continuous service temperature range. The material carries a published service range of -65°F (-53.9°C) to 500°F (260°C). Exposure to molten alkali metals or service requiring elastic recovery will shorten service life.

Maintenance and OEM teams specify it across food and beverage, laboratory equipment, and aggressive-media pipelines.

Order part number TST157SO, sold individually. Nominal inside diameter is listed as 4 1/2 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.