2103-228 PTFE S/T BUP FDA

APG stocks the TST228, an AS568-228 white PTFE (Teflon) 55 Shore D Back-Up Ring supplied with an inside diameter of 2.234 in (56.74 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 2.512 in (63.8 mm). A back-up ring installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

As a material, PTFE (Teflon) offers a very wide continuous service temperature range and non-stick, non-contaminating surface characteristics. The compound resists steam, oxidizing media, and nearly all industrial chemicals. Continuous operating temperature is published at -65°F (-53.9°C) to 500°F (260°C). It should not be specified for service in service requiring elastic recovery or elemental fluorine at temperature.

Typical settings include pharmaceutical and biotech, semiconductor fabrication, and food and beverage.

This item is sold individually under part number TST228. Nominal inside diameter is listed as 2 1/4 inch. Review your operating media and conditions against this specification before installation. 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.