In order to achieve fast testing of steel pipes in high-speed production lines, a magnetic flux leakage (MFL) technique based on orthogonal magnetization was proposed for the first time, which only requires axial linear scanning by a linear motion of the pipe at a high speed, rather than conventional helical scanning at a low speed. The feasibility and practicability of the approach were verified by the application of a high-speed testing apparatus. Meanwhile, the analysis of circumferential magnetization characteristics and optimization designs for magnetizers and testing probes were conducted by finite element methods, which are helpful for the circumferential magnetizer design. The proposed technique in this paper can greatly improve testing speeds to meet the requirements of rapid production, and can also accomplish fast detection for pipes where circumferential self-rotation is difficult, such as coiled tubing and square tubing.
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