Research on the Forward Solving Method of Defect Leakage Signal Based on the Non-Uniform Magnetic Charge Model

• Published in: Sensors (Basel, Switzerland) Vol. 23; no. 13; p. 6221
• Main Authors: Gao, Pengfei, Geng, Hao, Yang, Lijian, Su, Yuming
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 07.07.2023; MDPI
• Subjects: Algorithms; Charge density; Charge distribution; Charged particles; Coupling agents; Defects; Density distribution; Excitation; Finite element analysis; Inspection; Leak detection; leakage magnetic field calculation; Magnetic charge density; magnetic dipole; Magnetic dipoles; Magnetic fields; Magnetic flux; Magnetic flux leakage testing; magnetic leakage signal; magnetic monopoles density; Magnetic Phenomena; Methods; Neural networks; Permeability; Physical Phenomena; rectangular defects; Signal distribution; Waveforms; magnetic monopoles density; rectangular defects; magnetic dipole; leakage magnetic field calculation; magnetic leakage signal
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s23136221

Pipeline magnetic flux leakage inspection is widely used in the evaluation of material defect detection due to its advantages of having no coupling agent and easy implementation. The quantification of defect size is an important part of magnetic flux leakage testing. Defects of different geometrical dimensions produce signal waveforms with different characteristics after excitation. The key to achieving defect quantification is an accurate description of the relationship between the magnetic leakage signal and the size. In this paper, a calculation model for solving the defect leakage field based on the non-uniform magnetic charge distribution of magnetic dipoles is developed. Based on the traditional uniformly distributed magnetic charge model, the magnetic charge density distribution model is improved. Considering the variation of magnetic charge density with different depth positions, the triaxial signal characteristics of the defect are obtained by vector synthesis calculation. Simultaneous design of excitation pulling experiment. The leakage field distribution of rectangular defects with different geometries is analyzed. The experimental results show that the change in defect size will have an impact on the area of the defect leakage field distribution, and the larger the length and wider the width of the defect, the more sensitive the impact on the leakage field distribution. The solution model is consistent with the experimentally obtained leakage signal distribution law, and the model is a practical guide by which to improve the quality of defect evaluation.