Inner corrosion defects can severely impact the reliability of the corroded pipeline. The mechanicalbehavior and failure pressure of the pipeline with single inner corrosion defect, multiple interactinginner corrosion defects and multilayer structural inner corrosion defect were investigated by nonlinearfinite element method in this paper. Effects of length, width and depth of the corrosion defect and innerpressure were discussed. The results demonstrate that von Mises stress and the plastic strain of thecorroded pipeline increase with the increasing of inner pressure. Failure pressure of the corrodedpipeline decreases with the increasing of length and depth of the corrosion defect, but width has asmall effect on it. The pipelines with multiple and multilayer corrosion defects were also studied.Stress concentration appears on the longitudinal separation of the interacting corrosion defects. Failurepressure of the pipeline with multiple inner defects is lower than it with single inner pressure. Stressconcentration and plastic deformation firstly occurs on the lowest layer of the corrosion defects andthen expands to other layers with the increasing of the inner pressure.
展开▼
