Study on Evaluation Method of Failure Pressure for Pipeline with Axially Adjacent Defects

The interaction between axially adjacent defects is more significant than that between circumferentially aligned defects. However, the existing failure pressure assessment methods cannot accurately predict the failure pressure of axial adjacent defects. In the paper, the finite element model is adopted to analyze the influence of defect size, distribution mode and spacing between adjacent defects on failure pressure. A new failure pressure evaluation method is proposed by establishing the effective depth calculation model of corrosion colony with different distribution model. The burst test of X52 pipeline is carried out to verify the applicability of the method. It shows that the results of new method are consistent with the test results of pipeline with various defects and steel grades.