Field experiences of using electrochemically integrated electrode arrays as corrosion monitoring probes for visualizing buried pipeline corrosion

Electrochemical corrosion probes designed based on an electrochemically integrated multielectrode array has been used as a practical means of acquiring in-situ and site-specific data from ‘invisible’ underground gas and water pipelines. Field and semi-field tests have been conducted to assess these probes for providing early warning of potential structural failure due to localized corrosion under complex buried pipeline conditions. Electrode array-based corrosion probes were successfully deployed in selected locations across Victoria Australia. The probes performed as expected, providing a new point of view over the field conditions and the corrosion processes affecting buried pipelines. In general, it was found that for bare metal probes the level of cathodic protection (CP) appeared to be one of the main factors determining corrosion susceptibility. On the other hand, for probes designed to simulate corrosion under disbonded coating areas, the hydrogeological conditions around the pipe were found to play a more important role than the level of CP applied. This paper also provides a brief discussion on future prospects.