Ultrasonic Signal Multiplex Technology for Dynamic Wheelset Defect Detection System

As one of the key components of railway transportation, the condition of railway wheel sets are essential, especially in heavy-load application. A method for dynamic wheel sets defect detection by applying ultrasonic testing technology is described in this paper. Totally 448 ultrasonic probes are needed and arranged alone the track. Ultrasonic signal multiplex technology is designed for time multiplexing of the ultrasonic electronic channels. With the help of this technology, only 5% quantity of ultrasonic electronic channels are needed comparing with using ultrasonic probe and ultrasonic electronic channel one by one. Due to the high-power transmitting and the sensitive receiving of ultrasonic signal, the signal in multiplexer electronic circuit should well shielded and switched. Multilayer electronic circuit board and reed relays are designed to keep the performance of ultrasonic signal. The dynamic wheel sets defect detection system has been applied in Wuhan depot, China and about 200 wheel sets are inspected each day.