Advances in Use of Internal Corrosion Predictive Modelling on Buried Crude Oil and Gas Pipelines

Inline inspection is one of the best pipeline assessment techniques for piggable crude oil pipelines. However, for difficult to pig pipelines where use of inline inspection is not practical, use of acceptable internal corrosion predictive flow modeling (ICPM) and accurate pipeline elevation profiles can be employed to ascertain water and solid accumulation locations and concurrent internal corrosion rates for the entire pipeline. These methodologies are part of Liquid Petroleum Internal Corrosion Direct Assessment (LP-ICDA) of AMPP SP0208 Standard Practices for crude oil pipelines. The LP-ICDA methodology assesses the likelihood of internal corrosion and includes existing methods of examination available to a pipeline operator to determine whether internal corrosion is present or may occur. The basis of LP-ICDA is identification and detailed examination of locations along a pipeline in which water or solids can accumulate for extended periods, allowing inferences to be made about the integrity of non-examined pipeline. If locations determined to have the highest susceptibility for long-term internally corrosive conditions are examined and found to be free of significant internal corrosion, other less susceptible locations may be free of internal corrosion. Since acceptable ICPMs can predict locations prone to internal corrosion, operators can proactively address internal corrosion concerns. Identifying internal corrosion susceptible locations with ICPM helps operators implement proactive and mitigative actions to prevent internal corrosion. This paper explores advances of ICPM, use of ICPM on crude oil pipelines, and real-life successful practical applications.