Ultimate Bending Capacity of Subsea Pipeline with Corrosion-dent Defects

Corrosion and dent are common defects in subsea pipelines, which may exist simultaneously during pipeline operation, and have a significant impact on the ultimate bending capacity of the pipeline. Beyond that, seabed settlement, seabed development, and other conditions may bend the pipeline or even cause buckling failure. In the paper, the ultimate bending capacity of oil and gas pipelines with corrosion-dent defects is studied with numerical simulation, the sensitivity of parameters affecting pipelines' ultimate bending capacity is analyzed, and the change rule of the ultimate bending capacity of oil and gas pipeline with corrosion-dent defects is obtained. The results show that the dent depth and corrosion depth have a significant impact on the ultimate moment bearing capacity of the pipeline, and have a close relationship with the type of corrosion. A prediction formula of the ultimate bending capacity of the oil and gas pipeline with corrosion-dent defects is proposed with the nonlinear regression method, which may provide some reference for the integrity assessment of oil and gas pipelines. © 2023 Editorial office of Ship Building of China. All rights reserved.