Proposal for Integration of DC Basis Technologies with Macro Tool Approach to Asses Active-Corrosion Sites in Buried Pipelines

摘要

Oil and gas pipelines systems deliver different high value commodities and most of these systems existed in buried conditions. The chemical/electrochemical aggressiveness of the heterogeneous environment surrounding the metallic structures due to the electrolyte (soil, water) corrosivity in different regions is difficult to assess by using isolated methods/approaches. The use of DC basis technologies, such as DCVG and CIS characterize the state of the coating and cathodic protection respectively. Electrochemical fundamentals and mathematical tools have guided the survey results to assess the corrosion control and prevention systems. The unification of properties inherent to the soil or electrolyte with the fundamentals of the electrochemistry can lead to maximize the outcome of the assessment of external corrosion. In this work the macro tool approach is proposed, the spatial and time conditions of the climate, chemical and physical properties influencing the soil is linked with the DC basis indirect surveys and electrochemical fundamental analysis. The proposal of the use of the macro tool is applied to different data of a buried 12 in diameter steel pipeline with coal tar enamel and impressed current.