水冷壁管腐蚀脉冲涡流检测信号处理与成像

Signal processing and imaging of pulsed eddy current testing for corrosion of water wall tubes

摘要: 为实现水冷壁脉冲涡流可视化检测,从信号滤波、信号特征提取以及成像等3个方面着手,提出了一种高灵敏度成像方法。通过定量对比不同滤波方法的信噪比,表明提出的滤波方法在脉冲涡流检测信号处理中具有显著效果。通过微分方法提取斜率特征进行成像,图像厚度表征准确度高,可实时成像,有助于现场人员及时发现缺陷。

Abstract: In order to realize the visualization of pulsed eddy current testing of water walls, a high sensitivity imaging method was proposed from three aspects of signal filtering, signal feature extraction and imaging. Through quantitative comparison of the signal to noise ratio of different filtering methods, it shows that the proposed filtering method has a significant effect in the signal processing of pulsed eddy current testing. The slope feature is extracted by differential method for imaging. The image thickness is characterized with high accuracy and can be imaged in real time, which is helpful for field personnel to find defects in time.