Ultrasonic System Design of Multi-Machine Parallel Processing Suitable for Online Flaw Detection of Railway Wheels

Wheels are an essential component that affects the running safety of railway vehicles. Real-time automatic non-destructive testing of wheel cracks is the key technology to ensure the running safety of railway vehicles. This paper proposes a pass-through piezoelectric ultrasonic flaw detection design and a high-speed acquisition system of ultrasonic signals based on the Fieldbus Control System (FCS), including ultrasonic signal transmission and echo signal processing, and high-speed acquisition. The hardware design block diagram is given, and the circuit design principle and related characteristics are analyzed. The design also fully considers the environmental factors of on-site use and implements the design of mechanical reliability, environmental reliability, and electromagnetic compatibility. The system fully uses the operational characteristics of sequential sampling in the wheel pass-through online flaw detection. It adopts single-machine time-division multiplexing and multi-machine parallel processing technology, which improves the utilization rate of high-speed AD and the consistency of each channel. The test results show that the relative error of detection of artificial defects is less than 1%, and the signal-to-noise ratio is greater than 40dB, which can meet the requirements of online flaw detection of railway vehicles.