Pipeline Condition Assessment—Locating, Diagnosing, and Mitigating Corrosion Damage

Pipeline Condition Assessment – Locating, Diagnosing, and Mitigating Corrosion Damage

Corrosion of pipe, both from the inside/out and from the outside/in, has been a problem that literally “comes with the territory”.  Many techniques exist for locating leaks in pipelines, which are applied in industry with varying levels of success.  Once located, proper failure analysis and diagnosis of the root cause for the corrosion that resulted in failure of the pipe is a key element for the successful mitigation and prevention of recurrence.  This involves a deliberate and programmed approach to investigate all possible causes, comprehensive gathering of field data, and performance of necessary laboratory analyses in order to reach an informed and scientifically justified conclusion. Mechanisms that are known to be associated with localized pipeline corrosion include pitting corrosion, crevice corrosion, microbiologically influenced corrosion (MIC), galvanic corrosion, flow assisted corrosion, and stray current corrosion.  These corrosion mechanisms can occur from the inside/out or from the outside/in and may occur at various stages of the deterioration and/or in combination with each other. 

 Once the root cause has been identified, mitigation and prevention techniques and procedures should be based on the outcome of such an analysis.  A particular mitigation method, which has proven to be successful in one instance, may not be successful in other circumstances.  Every installation has some unique features in terms of environment and possible contributing factors to corrosion, which should be taken into consideration during failure analysis and subsequent identification of mitigation techniques and prevention methodologies.

 This paper will provide attendees with the key elements of such a programmed and integrated failure analysis and diagnosis approach.  Case studies of field experience with pipe failures will be utilized to illustrate various aspects of this approach, including general and localized corrosion and microbiologically influenced corrosion.