Comparasion of the detection performance of magnetic flux leakage and magnetic field disturbance in weld defect of turbine tower

The turbine tower exhibits a variety of weld defects, which not only pose a significant threat to its structural integrity but also present a substantial challenge for non-destructive testing of the welding zone. This study investigated and compared the detection methods and characteristics of magnetic flux leakage (MFL) and magnetic field disturbance (MFD) in the weld area of the turbine tower through experimental analysis, providing a foundation for comprehensive detection of weld defects using both approaches. Firstly, the MFL and MFD array sensors specifically designed for weld defect detection were developed. Additionally, four types of defect samples and constructed a comprehensive test platform were prepared. Secondly, Scanning results were obtained using the MFL and magnetic disturbance multi-channel arrays under various defect conditions. These defects were then imaged using an interpolation imaging method. Finally, by comparing and analyzing the detection results, it was found that MFL detection outperformed MFD in terms of detecting small-width cracks and characterizing hole depths. On the other hand, MFD was more effective in detecting small-angle cracks and smaller-sized hole defects.