EXPERIMENTAL INVESTIGATION OF THE DYNAMIC DEFECT FIELD WITH MOVING ELECTROMEGNETIC FLAW DETECTION OF RAILS

EKSPERIMENTAL'NOE ISSLEDOVANIE DINAMICHEKOGO POLIA DEFEKTA PRI SKOROSTNOI ELEKTROMAGNITNOI DEFEKTOSKOPII REL'SOV

This work presents results of experiments carried out on dynamic defect fields, studying the magnetostatic and eddy current components separately and the resulting dynamic defect field. Previously studied were the characteristics of this field on rails magnetized by the moving of the permanent magnet field; an image was obtained of the longitudinal defects. By means of an approximation, the significance of the eddy-current defect field was calculated. The component of the dynamic defect field caused by the magnetized rail was determined in the regular manner by static magnetization. The eddy current component was reproduced under laboratory conditions using a model. The longitudinal inductive current flowing through the rail head under realistic conditions was substituted for by a direct electrical current corresponding to the standard. Conclusions: (1) The eddy current field from rail defects differs from the magnetostatic according to the form, size and amplitude; the longitudinal component of the eddy current field resembles the vertical and transverse components of the magnetostatic field and vice versa; the components of the eddy-current field are two to three times greater in amplitude along the rail. (2) The resulting dynamic field corresponds to the model obtained by summation of the magnetostatic and eddy current fields; the resulting field of internal defects differs from the magnetostatic and resembles the eddy current while the field of joints and rail fissures is closest to the magnetostatic. (2) Results from track inspection cars may be interpreted.

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  • Supplemental Notes:
    • Full translation available for reference purposes at the Office of R&D, FRA. Contact Technology Planning Officer.
  • Corporate Authors:

    Plenum Publishing Company

    227 West 17th Street
    New York, NY  USA  10011
  • Authors:
    • Dovnar, B P
    • Vlasov, V V
    • Shcherbinina, V A
  • Publication Date: 1973

Language

  • Russian

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00130272
  • Record Type: Publication
  • Source Agency: Federal Railroad Administration
  • Files: TRIS, USDOT
  • Created Date: Dec 1 1977 12:00AM