Citation

Li Z, Li C, Cheng T, He Y. China Saf. Sci. J. 2019; 29(6): 122-127.

Copyright

(Copyright © 2019, China Occupational Safety and Health Association, Publisher Gai Xue bao)

DOI

10.16265/j.cnki.issn1003-3033.2019.06.020

PMID

unavailable

Abstract

In order to improve the accuracy of magnetic memory testing of buried pipelines and reduce the interference of external factors on magnetic memory signals, the effect of electromagnetic method on buried pipelines' magnetic memory is studied by using enhanced magnetic memory detection technology. Firstly, based on the analysis of the magnetization principle of pipelines, the change of magnetization intensity along with that of external magnetic fields was analyzed. Then, a computational model for the gradient modulus of magnetic induction intensity applied to buried pipelines by electromagnetic method was established, and the influence of current on gradient modulus of magnetic induction intensity was analyzed. Finally, the electromagnetic method was used in the magnetic memory testing of some buried pipelines, and its testing results were compared with the results under the geomagnetic field. The results show that the growth rate of pipelines' magnetization intensity is larger under the geomagnetic field, and the application of electromagnetic method can strengthen pipelines' magnetization and increase magnetic induction gradient modulus of the defect, which can highlight the characteristics of the magnetic memory signal at the defect and suppress the influence of interference factors, therefore improving the magnetic memory testing sensibility of buried pipelines. © 2019 China Safety Science Journal

Language: zh