Research On Micro-magnetic Testing System Of Train Wheels

In our country,the railway is an important national infrastructure.Rail transport in the integrated transport system has played an indispensable role.With the expansion of the scope of application about rail transport and technical indicators improving,the safety of train operating standards are also escalating.As a key part of the train traffic,the safe operation of the train wheels is related to the safety of the train.However,the conventional detection method of the train wheels has the shortcomings such as the complicated operation procedure,the low detection efficiency and the blind area of the detection.And a variety of conventional detection ways are used in combination to complete the different parts of the train wheels of conventional testing,greatly reducing the efficiency and increasing costs.Based on the above problems,this paper aimed to develop a train wheels detection system based on micro-magnetic testing.Deriving from the current situation of train wheels detection,geomagnetic field analysis,the magnetic properties of different materials and the magnetic effect in the fatigue process of ferromagnetic material,combining with the principle of micro-magnetic testing method,this paper analyzed the feasibility of micro-magnetic testing method applied to train wheels detection.According to the overall performance requirements of train wheels micro-magnetic detection system,the overall design scheme of the system was designed,including the hardware part design and the software part design.The hardware part mainly included the tooling design of the detection probe,the choice of the transmission protocol and the communication way of the lower computer and the host computer,and the design of the power supply system.An eight-channel detection probe was designed according to the specific detection requirements of the train wheels and the actual surface size.The detection range of the probe covered the flange,tread and rim parts.The UDP protocol in Ethernet was chosen as the transmission protocol between the host computer and the lower computer,moreover the wired and wireless communication modes were designed to meet the requirements of different detection environments.Power supply system provided convenient to user by designed monitoring function for the battery power.The software part mainly included real-time data acquisition system design,tread detection system design,flange detection system design and battery status monitoring systemdesign.In the software part,the interface design of each detection module was completed,the algorithm of micro-magnetic detection defect extraction was designed,and a defect imaging algorithm based on Hermite interpolation was proposed.Finally,this paper combined the hardware and the software to form a complete set of detection system which could test flange,tread and rim of the train wheels.The influence of different defect size and burial depth on the detection results was summarized by simulation analysis,and the relevant conclusions of the simulation analysis were verified by the actual test results.The detection result of the actual train wheels could show that the detection system had the advantages of simple operation,high detection efficiency,high detection precision,visualized and reliable test results,and achieved the expected design requirements.