管道漏磁检测探头提离效应仿真分析

Simulation Analysis of MFL Detection Probe Lift-off Effect

对漏磁检测探头提离效应进行了探讨,建立了裂纹缺陷漏磁检测提离效应分析模型,分析了裂纹缺陷磁偶极子二维数学解析模型,研究了探头提离值对漏磁信号的影响规律。研究发现,在漏磁检测过程中,探头提离效应会影响磁场强度,随着提离值的增大,检测到的漏磁场强度由强变弱。提离值增大到一定值后,漏磁场强度达到一个恒定值,即对漏磁场的测量已经失去意义。因此要求在设计漏磁检测装置时,必须充分考虑检测探头提离效应的影响,以提高检测准确性。

The issue of magnetic flux leakage （MFL） detection probe lift-off effect is discussed. With the establishment of a model of the probe lift-off effect of magnetic flux leakage detection for crack defects, the two-dimensional mathematical analysis model of crack defects magnetic dipole is analyzed, and the influence rule of detection probe lift-off effect on magnetic flux leakage signals is studied. The research shows that the probe lift-off effect will affect the magnetic field strength in the process of the magnetic flux leakage detection. With the lift-off value increasing, the detected leakage magnetic field strength changes from strong to weak. And when the lift-off value increases to a certain one, the leakage magnetic field strength achieves a consant value, which indicates that the measurement of the leakage magnetic field has become meaningless. Consqeuently, it is required that detection probe lift-off effect should be fully taken into considertaion when designing magnetic flux leakage detection device, in order to improve the accuracy of detection.