钢管, 周向磁化, 漏磁检测, 有限元

In order to optimize the magnetizer of the circumferential MFL(C-MFL) detector for pipe inspection, the distribution of magnetic induction field in pipe wall under circumferential magnetization was simulated and studied based on 3D finite element method.The influences of such pipe parameters as diameter and wall thickness on the circumferential magnetic induction in pipe wall were analyzed,and the effects of the applied circumferential field on the induced field, the magnetic leakage field and the background magnetic field were also investigated.The simulation results show that the increase of the pipe diameter will increase the effective detected area, and the increase of the pipe thickness will also increase the effective detected area but decrease the induced magnetic field clearly. Moreover, the increase of the magnetization field is beneficial to testing the axial defect of pipes. However, some effective signal processing algorithms should be developed to eliminate the background magnetic field from the acquired magnetic leakage field.