The NDT Methods And The Application Research Of NDT Methods In Rail Flaw Detection

With the rapid improvement of science and technology, modern industry is growing fast,which drives railway transportation development rapidly. Due to the increasement of railway mileage, the coverage of railway network expanded. At the same time the railway transport capacity greatly improved, for the large range of railway transportation speed up. On the other hand, the safety event of railway transportation occured once, the loss also is multiplied, even could not predict. With acceleration of railway transportation, rail safety problems occur more and more frequently. The economic losses, casualties and influence on society were also difficult to estimate. Therefore, in order to improve the safety of railway transportation, reliability, the development and application of nondestructive testing technology for detection of rail damage is necessary.To overcome the existing rail flaw detector’s imperfection which is that the the range of flaw detection is not large enough and the the detection precision is not high enough, the corresponding optimization scheme is put forward which make the service rail’s rail head and rail waist no blind spot detection achieved. In order to keep the time domain and frequency domain information of ultrasonic signal completion, the optimized signal processing algorithm, wavelet transform is applied to ultrasonic signal processing, which effectively improve the detection rate of rail flaw. The application of neural networks in ultrasonic flaw detection, can realize the intelligence of rail flaw judgment, so as to effectively reduce the detection work intensity of workers, at the same time avoid the possible false negatives and the phenomenon of wrongful convictions which is caused by the human factor.In this paper, according to the research project purpose, contents and requirements, summarizes the the rail flaw detection research situation and development trend domestic and overseas, introduces the nondestructive testing technology and analyzes the characteristics of nondestructive testing technology, method, evaluation and reliability. Then, introduce the nondestructive testing of steel rail flaw detection method in detail and the research on data processing of ultrasonic signal are analyzed.