管道导波无损检测回波信号处理方法研究

Study on a method of echo signal processing for guided waves nondestructive testing of pipes

简述了导波在管道中传播的频散特性,给出了管道导波无损检测实验信号特征。对管道导波检测的回波信号首先进行Hilbert变换,然后对变换后的信号分别进行加窗函数滤波和小波变换,处理后的缺陷信号明显易于辨别。经过分析比较,结果表明了这两种组合方法用于管道导波无损检测信号处理的效果基本一样,在实际检测应用中,选取其中任一组合方法都是可行的。

The dispersion characteristic of guided wave propagation in pipes was described and the experimental signals feature of guided waves NDT of pipes was given. The Hilbert transform method was used for processing the echo signals detected by guided waves in pipe, and then the transformed signals were processed respectively with digital window function filter and wavelet transform methods. The defect signals could be easily distinguished after being processed. The analysis and compare results show that the effect by using two kinds of combined methods to process the signals of guided waves NDT of pipes are nearly the same. So selecting either of the combined signal processing methods is feasible in the practical testing.