用于铁路接触网零部件的便携式超声检测仪设计

基于超声无损检测技术,对典型的接触网零部件销钉进行了超声检测方法的研究,设计了接触网零部件缺陷的便携式超声检测仪。仪器基于FPGA(现场可编程门阵列)设计,使用双极型脉冲信号激励换能器,放大电路可实现-20～60dB的程控增益调节,采样率高达2.5×105 s^-1,该仪器可以实现缺陷回波信号的自动识别。对带有人工裂纹和模拟疲劳裂纹的试件进行检测,验证了方法的可行性和仪器的可靠性。便携式超声检测仪具有分辨率高、自动化程度强等优势,能够满足工作现场的快速检测需求。

Design of Portable Ultrasonic Detector for Railway Catenary Components

Based on ultrasonic nondestructive test,the ultrasonic testing method for the pin of typical component on the catenaries is studied.Then a flaw detector for catenary components is designed.The instrument is based on FPGA and its main components are a bipolar pulser,a-20-60 dB program-controlled amplifier and an A/D convertor with a digitalization rate of 2.5×10^5s^-1.The software of detector is capable of recognizing the crack reflection signal automatically.In the study,both artificial crack and simulative fatigue crack were tested to prove the feasibility of detection method and the reliability of instrument.The portable ultrasonic flaw detector for railway catenary components has advantage of high resolution and automation,which can meet requirement of rapid detection in field work.