Influence of motion induced eddy current on the magnetization of steel pipe and MFL signal

Issue title: Proceedings from the 17th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2015)

Guest editors: Fumio Kojima, Futoshi Kobayashi and Hiroyuki Nakamoto

Article type: Research Article

Authors: Feng, Bo^a | Kang, Yihua^{a; *} | Sun, Yanhua^a | Yang, Yun^a | Yan, Xizi^b

Affiliations: [a] School of Mechanical Science & Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China | [b] Wuhan Institute of Technology, Wuhan, Hubei, China

Correspondence: [*] Corresponding author: Yihua Kang, School of Mechanical Science & Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, Hubei, China. E-mail:yihuakang@hust.edu.cn

Abstract: In order to get a thorough comprehension on how the eddy current affects the MFL signal in high speed testing, distribution of eddy current and the magnetic field generated by it are first analysed theoretically. Then, the magnetization statuses of the pipe in static and motional situations are investigated by finite element simulation. Finally the external and internal defect signals are extracted in both static and motional cases. The results show that, in high speed testing, the magnetic field is strengthened at the outer surface and weakened at the inner surface, which increases the external defect signal but decreases internal defect signal.

Keywords: Magnetic flux leakage (MFL), high speed testing, eddy current effect, velocity effect

DOI: 10.3233/JAE-162076

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 52, no. 1-2, pp. 357-362, 2016