论文部分内容阅读
通过实验和有限元分析研究了检测磁性管用的远场涡流技术.管子内壁周围磁场因远场区的缺陷而明显变化.采用远场涡流技术可以相同的灵敏度从管子内壁同时检测到管子内、外壁缺陷,检测缺陷深度用缺陷信号的相位较幅度更为合适。缺陷信号幅度指示随测试频率的加大而减小,而相位指示则在某个频率上达到最大.文中阐述了管子电磁特性对远场涡流的影响,这对测试频率的选择将起到指导作用.
The far-field eddy current technology for the detection of magnetic tubes was studied through experiments and finite element analysis. The magnetic field around the inner wall of the tube obviously changed due to the defects in the far-field region.The far-field eddy current technology can detect the inner and outer walls of the tube from the inner wall of the tube with the same sensitivity Defect, the depth of the defect detection signal with a defect phase amplitude more appropriate. The indication of the amplitude of the defect signal decreases with the increase of the test frequency, and the phase indication reaches the maximum at a certain frequency. The influence of the electromagnetic characteristics of the tube on the far-field vortex flow is explained in the paper, which will guide the selection of the test frequency .