Recent enhancements in the Magnetic Flux Leakage (MFL) in-line inspection (ILI) technology has enabled more reliable detection and more accurate reporting of a greater range of anomaly types than ever before, though the true value rests with what the integrity engineering specialists are able to do with the enhanced information to translate it into an actionable Integrity Management Plan. This paper describes how the enhanced information can be used in engineering criticality assessments and the benefits this brings to the operator in the form of integrity management decision-making with higher confidence, reduced investigation and repair costs and less operational disruption from ILI activity. This paper demonstrates how the new holistic data approach brings a seamless transition from raw inspection data to an actionable integrity report, with more advanced assessment of metal loss and mechanical damage data. Engineering criticality assessments are used to illustrate how the enhanced ILI information is used and how the results benefit integrity management decision-making. For example: • Fitness for Service corrosion assessment determines the immediate and future integrity needs by evaluating the criticality of corrosion anomalies identified during an ILI. Taking account of the reduced ILI uncertainty associated with the new MFL technology, the immediate and short-term response schedules can be developed with higher confidence than before and long term remediation activities and re-inspection intervals can be truly optimized. • For re-inspections, the focus is on the determination of accurate corrosion growth rates. Using signal-matching techniques, active corrosion sites can be identified and the corrosion growth rates estimated with high confidence. This provides the basis for optimizing the long-term remediation activities and re-inspection intervals. • The ability to account for coincidental anomalies and loading conditions, e.g., the occurrence of bending strains resulting from loss of ground support coincident with girth weld anomalies, circumferential corrosion or denting/buckling are important integrity considerations that influence how the anomalies are assessed. • Improved Caliper sensor resolution enables the dent profile to be visualized more accurately leading to improvements in the way dents are assessed, i.e. using strain-based methods. Reliable detection of gouging within dents is an essential component for establishing the cause and assessing the severity of dents and has always been challenging for conventional MFL ILI tools. This enhanced MFL technology enables metal loss within dents to be detected and viewed via a Triaxial magnetic sensor system, providing more information of the nature of the metal loss within the dent.

This content is only available via PDF.
You do not currently have access to this content.