钢轨轨腰缺陷激光-电磁超声检测及信号处理  

Research on the rail waist defect testing with laser-EMAT ultrasonic and signal processing

作　　者：孙继华[1] 赵扬[1] 南钢洋[1] 马健[1] 刘帅[1] 王启武[1] 巨阳[1] 

机构地区：[1]山东省科学院激光研究所,济南250103

出　　处：《激光杂志》2017年第12期22-25,共4页Laser Journal

基　　金：山东省自然科学基金(ZR2016FB26);山东省重点研发计划(2016ZDJQ0401);山东省科学院杰出青年计划(201505)

摘　　要：钢轨是列车运行的承载结构,钢轨的轨腰缺陷是影响行车安全的缺陷之一。为了提高对钢轨轨腰缺陷的检测能力,针对钢轨轨腰缺陷的特点,设计了钢轨轨腰缺陷激光-电磁超声检测系统及信号处理方法。通过使用该系统对钢轨试样进行试验,可以有效的检测出钢轨轨腰处Φ6mm和Φ8mm的通孔缺陷;通过采用小波阈值去噪技术对实际检测信号进行处理,可以极大的提高信号的信噪比,从而得到满意的去噪效果,经去噪处理后的信号更有利于缺陷的识别。通过试验和信号处理表明,钢轨轨腰缺陷激光-电磁超声检测系统能有效的实现钢轨轨腰缺陷的非接触检测,通过该系统的研究可以为钢轨缺陷超声检测技术的改进提供一定的参考。The rail is the bearing structure of train running, and rail waist defect is one of the defects of affecting the safety of running. According to the rail waist defect features, the laser-EMAT（ Electromagnetic Acoustic Transducer） testing system and signal processing were designed to improve the detection ability of rail waist defect. Then the test of the rail testing sample was carried out by using this system. The testing results show that the system can effectually detect the rail waist through hole defects of ~ 6ram and f 8mm. From the laser-EMAT original signal processing based on wavelet threshold denoising, it could be seen that the SNR was greatly improved and remained all characteristics of the original signal, thus the signal that processed by the wavelet threshold denoising will be convenient for the damages identification. The experimental research and signal analysis showed that this system can realize the complete non-contact detection on rail waist defects. Though the research of the system, it provides a certain reference for the improvement of ultrasonic testing technology of rail defects.

关 键 词：激光-电磁超声技术 轨腰缺陷 超声检测 信号处理 小波阈值去噪 

分 类 号：TN249[电子电信—物理电子学] U216.3[交通运输工程—道路与铁道工程]