【摘要】 在管道内部,基于远场涡流技术的局部缺陷定量检测中,当发射线圈处于管道缺陷位置时,接收线圈检测的远场涡流信号中叠加了发射线圈处缺陷造成的伪峰信号,影响了接收线圈处管道缺陷定量分析的正确性.为了实现基于远场涡流检测中局部缺陷正确的定量分析,本文在远场区域设置与发射线圈同轴的多接收线圈以及周向传感器阵列.同轴接收线圈用来获取远场涡流检测信号中的伪峰信号,周向传感器阵列用来检测局部缺陷.该方法通过两个接收线圈获取具有差分特性的两个远场涡流检测信号,然后利用维纳去卷积滤波器实现伪峰信号的获取,同时滤除测试中的噪声;最后,在用于局部缺陷定量分析的涡流信号(由阵列传感器获取)中减去伪峰信号,达到检测管道局部缺陷的目的.该方法通过实验仪器得到验证,在管道局部缺陷的定量检测中具有很好的实用性.更多还原

【Abstract】 In the internal inspection of pipes based on Remote Field Eddy Current( RFEC),when transmitter passed by defects on pipe, signals tested by receivers is superimposed by the secondary peaks. Secondary peaks are caused by defects locate near transmitter, and lead to wrong assessment of qualification of defects. This paper applied dual receivers for removing secondary peaks. In proposed method, two receivers are set coaxially to transmitter in remote field to get two differential signals. With these two differential signals,Wiener deconvolution filter is employed to obtain secondary peaks and filter testing noise. Further, an array of sensors is set in remote field to test local defects. The secondary peaks can be subtracted from signals tested by sensors by using the dual-receiver. The feasibility of proposed method is validated by testing tool and experimental pipe.更多还原