Failure Analysis: Disbonded Coating and Cathodic Protection Shielding for Pipelines And Utility Poles

From JPCL, July 2017

By Mehrooz Zamanzadeh, Matco Services, Inc. and George T. Bayer, Exova

This article emphasizes the basic problems and applied aspects of failures encountered at three separate structures and details the factors and mechanisms affecting them. In underground structures protected by cathodic protection, coatings should be selected that do not shield cathodic currents. Coatings that shield cathodic protection have resulted in localized corrosion, perforation and in some instances, explosions in gas pipelines....