| Abstract Scope |
Buried pipelines are protected from corrosion attack by coating and cathodic protection (CP). However, excessive CP could cause serious damage to pipeline coatings and, consequently, pipeline integrity.
The corrosion performance of excessive CP-protected pipelines coated with three different coatings was investigated through cathodic disbondment (CD) tests, electrochemical impedance spectroscopy (EIS), and DC current density monitoring.
The results indicate that more negative CP potentials generate a more alkaline environment, leading to an increase in the cathodic disbondment area over time. Furthermore, the coatings failed, as evidenced by a negative shift in DC current density and a decrease in the impedance modulus.
This research is expected to contribute to the development of effective corrosion mitigation strategies for coated pipelines subjected to excessive cathodic protection, ensuring the long-term integrity and reliability of buried pipeline infrastructure. |