铁磁性小径管道的脉冲双远场涡流检测

Detection of Ferromagnetic Small Diameter Pipes by Double Far Field Eddy Current

针对小径管缺陷检测中的线圈感应电压峰值和过零时间点太接近,从而降低了检测分辨率的问题,提出了一种改进的脉冲双远场涡流检测技术,将两端激励线圈分别施加不同频率的脉冲信号,此时中间检测线圈的信号会出现极高峰值,不同缺陷有不同的极高峰值与其对应,通过极高峰值便可确定管道的缺陷性质。利用有限元软件ANSYS Maxwell进行了建模仿真分析,表明该方法可以初步实现缺陷类型和缺陷性质的判断。

Since the peak value of the induced voltage of the detection coil and the zero-crossing time point are too close in the detection of a small diameter pipeline defect,the detection resolution will be reduced.Therefore,this paper presents an improved pulsed far field eddy current testing technology.The pulse signals of different frequencies are applied to the excitation coils at both ends.At this time,the signal of the middle detection coil shows a very high peak.Different defects have different extremely high peaks and correspond to each other,and the degree of defect of the pipeline can be determined through extremely high peaks.This article uses the finite element software ANSYS Maxwell modeling simulation analysis,shows that this method can initially realize the defect type and the defect degree judgment.