Full-Scale Testing of Corrosion Resistant Alloy-Mechanically Lined Pipes for Submarine Pipelines

Abstract This study evaluates the fatigue performance of corrosion-resistant alloy (CRA)-mechanically lined pipes, focusing on the critical triple point, where the CRA liner, weld overlay, and backing steel pipe intersect. Through full-scale bending tests and full-scale resonance fatigue tests, real-world operational and installation conditions were simulated to assess fatigue resistance, particularly at the triple point—an area not adequately addressed in current industry standards. The results reveal that the triple point exhibits excellent fatigue performance, exceeding the criteria of existing guidelines, despite the lack of specific provisions for this critical region. This study provides valuable data to inform updates to industry standards, enhancing the safety and reliability of subsea pipeline operations.