The Importance of PTFE/FEP/PFA LINING

The Chemical Process Industry (CPI) faces many challenges while handling highly corrosive and pure media both while processing and while treating the process wastes and effluents. The combination of elevated
temperatures and pressures affect severely the life of conventional systems and successful containment of corrosion needs alternative systems which are cost-effective, safe and environmentally responsible.

These conditions have created the need for more corrosion resistance equipment and piping suitable for aggressive chemicals and multi-component mixtures irrespective of composition over a wide range of pH. There are materials which can solve most of the corrosion problems, however, some process conditions exceed the capabilities of even the most expensive and exotic metals and alloys.

As an alternative engineering plastics, fluoropolymers as these materials are generally called, provide successful containment facilities in most of the cases. Fluoropolymers are highly corrosion resistant to a wider range of chemicals at varying concentrations and pH.

A ready reference for selection of Fluoropolymers:

PTFE PFA FEP HDPE PP PVDF
Theoretical maximum Temperature 260° C 260° C 205° C 121° C 121° C 135° C
Recommended difference between maximum Temperature 200° C 200° C 160° C 60° C-70° C 60° C Temp. is different for different materials
Solvents No known impact Refer detailed CorrosionResistance Chart to ensure chemical compatibility Common Ketones
Corrosion Resistance Virtually all chemicals except fluorine & its compounds and violent reducing agents like metallic sodium and molten alkali metals Refer Resistance Chart