Numerical simulation study on magnetic flux leakage testing signals of combined defects in oil and gas pipelines
To deal with the problem of mutual interference and difficulty in identifying the magnetic flux leakage testing sig-nals between the combined defects of pipeline,a simulation model was established by using the finite element method,and the laws of magnetic flux leakage testing signals inside and outside the pipeline of the defects with different shapes and the adja-cent internal and external combined defects were studied.The results show that there are significant differences in the axial and radial components of magnetic flux leakage testing signals of pipeline defects.The testing signals of the combined defects have mutual interference and certain superposition.When the defect depth is about 10%,25%,and 40%of the pipeline wall thickness,the interference distance of axial signals is about 1,2,and 3 times as the defect length,respectively,and the inter-ference distance of radial signals is about 4 times as the length.The mutual interference degree of combined defect radial sig-nals is greater than that of axial signals,and the influence of defect depth on axial signals is greater than that of radial signals.The research results can provide a theoretical basis for identifying the combined defects in oil and gas pipelines.
NETL
NSTL
万方数据
维普
