Asset Integrity Management and Fitness-for-Service Assessment of a Pipe Elbow With Metal Loss

The objective of this paper is to describe the inspection process and examine a piping elbow found to have metal loss within the context of Asset Integrity Management (AIM). During the last five years, Industry 4.0 technology involving mobile tablet and cloud technology has merged with the proven concepts of AIM enterprise systems. Before this shift, inspectors, engineers, and managers relied on unreliable and time-consuming methods. New technologies allow inspectors and mangers to think, react, and communicate quickly and proactively when integrity threats are discovered. A piping elbow was identified at a thickness monitoring location (TML) within a larger system due to existing internal corrosion and/or erosion. Since the metal loss is internal, an external visual examination was not sufficient to monitor the metal loss. External ultrasonic (UT) inspection was used to measure the thickness at multiple points on a grid pattern drawn on the elbow’s external surface. The thickness measurements provide the data needed for a local metal loss assessment. An AIM program was used to assess the risks, aid in inspection, and develop an assessment for ascertaining the degradation pattern. With a heightened understanding of the asset’s degradation pattern, the risk to the asset is reassessed continuously until it has been reduced to an acceptable level as defined by the stake holders.