针对现有漏磁场解析时假设磁荷均匀分布的计算结果与工程结果误差较大的问题,对管道缺陷磁化后磁荷的不均匀分布规律进行研究,得到了管道缺陷侧壁和棱线上的磁荷分布特征。基于磁偶极子理论建立了管道缺陷的三维磁偶极子解析模型,对缺陷棱线磁荷和侧壁非均匀面磁荷产生的漏磁场进行解算,并进行了试验研究。结果表明,计算结果与实际管道缺陷漏磁场的分布特征具有很好的一致性,误差小于假设磁荷均匀分布得到的漏磁场,说明所建模型可有效描述管道矩形缺陷漏磁场的分布特征。

Aiming to reduce the large error between the assumed uniform magnetic charge distribution in the analysis of leakage magnetic field and the actual engineering results, the non-uniform distribution law of magnetic charge after magnetization of pipeline defects was studied, and the distribution characteristics of magnetic charge on the side wall and edges of pipeline defects were obtained. Based on the magnetic dipole theory, the three-dimensional magnetic dipole analytical model of pipeline defect was established, the leakage magnetic field generated by the edge magnetic charge of the defect and the magnetic charge of the non-uniform surface of the side wall was solved, and the experimental research was carried out. The calculation results and the actual defect leakage magnetic field distribution characteristics of pipeline were in very good consistency, and the actual error of the leakage magnetic field was smaller than that while the distribution of magnetic charge being assumed uniform. It is shown that the model can effectively describe the distribution characteristics of leakage magnetic field with rectangular defects.