Dissertation > Excellent graduate degree dissertation topics show

Defect Recognition in High-speed Rail by MFL Technology

Author: CuiLiDong
Tutor: WangHaiTao
School: Nanjing University of Aeronautics and Astronautics
Course: Measuring Technology and Instruments
Keywords: Magnetic flux leakage Rail detection Feature analysis Defect identification Speed effect
CLC: U213.43
Type: Master's thesis
Year: 2011
Downloads: 80
Quote: 0
Read: Download Dissertation

Abstract


Train speed increasing and the large scope lying of high-speed railway have played important roles to promote the speed of economic development. The way to accurately and quickly non-destructive test on high speed railway rails has a very important significance to protect the passenger and freight train transportation safety. The existing main inspection technologies for rail detection are ultrasonic and magnetic primary, the speed of ultrasonic testing is limited, due to the need of coupling agent, and electromagnetic detection products are mostly monopolized by foreign companies, therefore, the implementation of the nationalization has great significance.This article describes the magnetic flux leakage testing technology in rail detection. First the basic principles of magnetic flux leakage testing is analyzed, and the theory of the magnetic leakage field flaw analysis techniques commonly used is introduced, the law of the change of magnetic leakage field’s two-dimensional component that caused by the change of groove defect’s size. Then the signal processing of the magnetic flux leakage in the rail detection and the choice of every part of it is analyzed, including signal acquisition, filtering, feature extraction and analysis. Because the characteristics of magnetic flux leakage signal, the wavelet denoising filter is selected in the comparison of fourier transform filtering and wavelet transform filter. At the same time, the method is learned that the features extraction of magnetic flux leakage signal and the relationship between defects and the MFL signal, and applied it to the recognition in the rail ramp cracks detection.In this article, the experimental study includes low-speed and high-speed rail detection systems, low-speed experimental part is based on artificial MFL cart rail crack detection system, the MFL signal is converted from time domain to space domain and the identification of rail cracks is studied. High-speed experimental part is based on wheel-form MFL rail crack detection platform, the signal of artificial cracks on the wheel is analyzed, then the low of MFL signal changing affect by speed-effect is found by compared the signals of same crack under different speed. Finally, a summary of the work of this article is given and the suggestions about the future in future direction and content are given, too.

Related Dissertations

  1. Spatial Analysis and Pollution Evaluation about Water Environment Actuality of Rural Surface Water in Typical Regions of Jiangsu Province,S271
  2. Stationary orbit satellites Area CCD imaging simulation analysis and integration time of the feature,TP751
  3. Researches of the Mine Safety Monitor System Based on the Data Mining,TP274
  4. A Study of Mandarin Textbook in Jakarta and Its Influence on Chinese Teaching,H195
  5. Analyse Tibetan Putonghua (Weizang Dailect Area) Pronounciation Characteristic,H102
  6. Analysis of "Degree Adverb +to Have +NP",H146
  7. Modern Chinese Semantic Research Action category,H146.111.111
  8. Nondestructive Testing Method and Tools for In-Service Ferromagnetic Heat Exchanger Tubes,TB657.5
  9. The Research of Defect Magnetic Flux Leakage Testing Quantized Technology Based on BP Neural Network,TP183
  10. Study on Technologies of Remote Sensing Feature Analysis and Information Extaction of Earthquake Disaster,P237
  11. Feature Extraction and Reasearch in the Application of Face Recognition,TP391.41
  12. Research of Face Recognition Algorithms Based on Local Feature Analysis,TP391.41
  13. Research and Implementation of Web Page Segmentation Algorithm MFPS Based on Multi-Feature,TP393.092
  14. Research on Construction of Schedule Management System for Large-scale Comprehensive Traffic Project,F542
  15. The Magnetic Flux Leakage Testing Method and System for Washover Pipe Thread,TE92
  16. The Islamic Culture of Iran and the Sino-Iran Cultural Intercommunication,K203
  17. The Feature and Stability Analysis of Niutouzui Landslide Group,P642.22
  18. Research on the Test System of Non-destructive Testing and Image Collection for Powerful Belt with Wire Rope Core,TD528.1
  19. Analysis of partial discharge of the high voltage capacitor DC,TM53
  20. Analysis of the Learner’s Characteristics on Adaptable Learning,G434

CLC: > Transportation > Rail transport > Railway Line Project > Line constructed > Rail > Rail flaw detection and instruments
© 2012 www.DissertationTopic.Net  Mobile