The Research And Development Of MFL Nondestructive Testing System

With the continuous development of society and the continuous progress of science and technology,the attendant is the field toward the depth and breadth of the continuous extension,and in the field of modern detection means of detection and detection accuracy also put forward new and higher requirements.Magnetic flux leakage detection technology has been widely used in defect detection,for the quantitative analysis of defects,it has been an important issue in the field of magnetic flux leakage testing.Firstly,the research status and the significance of the magnetic flux leakage nondestructive testing are introduced.The basic theory of the electromagnetic field and the calculation method of the magnetic flux leakage are expounded.The preprocessing of the wavelet denoising signal of the magnetic flux leakage signal is discussed,and the method of improving the spatial resolution based on the fitting reduction is discussed.Based on the magnetic flux leakage Bx and By distribution,the magnetic flux leakage characteristics of Bx peak and By peak valley are proposed,which are not affected by the defect width and can be used for the quantitative evaluation of defect depth.The influencing factors of magnetic flux leakage testing are analyzed,and the relationship between the magnetic conduction characteristics and temperature is studied.Using simulation software ANSYS Workbench the typical defects of magnetic flux leakage testing simulation,the introduction of the model parameters of the device and mesh;magnetic flux leakage testing model with different defect characteristics is established,the analysis of different geometrical size defects of BX,by characteristics,and to establish the characteristic defects and magnetic flux leakage between the eigenvalues and the quantitative relationship of temperature effects on leakage magnetic field,is discussed.The simulation results and analysis provide a reference for the qualitative and quantitative analysis of defects and the method of temperature enhancement.The leakage magnetic nondestructive testing system is designed,and the main hardware components are designed and made.Design the U type excitation device,array type sensor probe,a signal conditioning circuit,detection analysis software is developed based on the LabVIEW platform.The leakage on-line magnetic signal acquisition,analysis,display,storage and other functions.Using the developed system are tested,shows that the leakage magnetic detection system has the defect of qualitative and quantitative analysis,to validate the effectiveness the proposed MFL character value and magnetic flux leakage signals of temperature enhancement method.At last,the main work of this paper is summarized in detail,and the prospect of the follow-up work and the work of further research are also summarized.