针对表面粗糙的钢管进行超声波检测时存在的噪声高、信噪比低的问题, 利用自行搭建的虚拟超声检测信号处理系统, 对表面粗糙钢管的超声检测信号分别进行了基于传统傅里叶变换的频谱分析和FIR滤波以及基于小波变换的时频分析和小波去噪。通过对比试验发现, 基于小波变换的信号处理技术可以对表面粗糙钢管的超声检测达到更好的去噪效果。

Using the signal processing system of virtual ultrasonic testing which was designed by ourselves, the ultrasonic testing signal of pipe with rough surface has been processed based on the Fourier transform and Wavelet transform respectively to solve the problem of low signal-to-noise ratio. The signal processing work that based on the Fourier transform is mainly refers to the spectrum analysis and FIR filter. The signal processing work based on the Wavelet transform is mainly refers to the time-frequency analysis and Wavelet denoising. By comparing the experimental results, it has shown that the Wavelet transform method was better than the Fourier transform when processing the ultrasonic testing signal of pipe with rough surface.