C2024-21182 Line Pipe DC-ERW Long Seam Weld Linear Anomaly Investigation

Luke Jain, alex hudgins, Lee Vest, Ransom Stamps, Rick Gonzales - Linear anomalies were discovered during construction activities near to the DC-ERW long seam weld of a 20-inch natural gas pipeline. Magnetic particle testing and phased array ultrasonic testing were applied to characterize the anomalies. Pipe samples were removed from the pipe for additional destructive laboratory analysis. Laboratory analysis included visual assessment, X-ray computed tomography, cryo-fracture, cross-sectioning, metallographic analysis, and scanning electron microscopy. Inspection and testing results indicated that the anomalies appeared consistent with roller contact marks introduced during pipe manufacturing and did not show evidence of time-dependent growth. Representative flaws were evaluated using a Failure Assessment Diagram to provide an additional level of assurance. All flaws were found to be acceptable in accordance with API 579 Part 9, Level 2.