TSP212 is an AS568-212 white PTFE (Teflon) 55 Shore D Back-Up Ring with an inside diameter of 0.859 in (21.82 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 1.137 in (28.88 mm). In service, this back-up ring bridges the extrusion gap so the primary seal holds its shape under load.
Expect good resistance to nearly all industrial chemicals, steam, and oxidizing media. PTFE (Teflon) is specified for non-stick, non-contaminating surface characteristics and one of the lowest coefficients of friction of any solid. Rated temperature range runs from -65°F (-53.9°C) to 500°F (260°C) in continuous service. Exposure to service requiring elastic recovery or molten alkali metals will shorten service life.
Common environments for this compound include pharmaceutical and biotech, chemical processing, and aggressive-media pipelines.
Reference part number TSP212 when ordering; the item is sold individually. Nominal inside diameter is listed as 7/8 inch. Check the compound against your process media, pressure and temperature before committing to a design. If you need a size, durometer or compound that is not listed, APG can cross-reference from a print, a sample or a competitor part number.
description 2107-212 PTFE SPIRAL B/U FDA
Actual_CS 0.139 inch (3.53 mm)
Actual_ID 0.859 inch (21.82 mm)
Actual_OD 1.137 inch (28.88 mm)
ProductCode Description O-Rings - Backup Rings