Pipeline Integrity Gauges Based on Dynamic Magnetic Coupling Sensing Technology

This paper proposes a novel sensing system for in-line-inspection of pipelines, based on dynamic coupled of integrating the magnetic perturbation with motive induced eddy current. This approach simultaneously addresses the key challenges of high energy-consumption as well as the detection of multi-types of defects. The sensing characteristics involves a novel probe structure incorporating a detection coil and ring-magnetic source, capable of identifying different defects at varying speed. In particular, the motion-induced eddy current can be theoretically modeled by the relative motion between the magnet and the pipe. Interpretation of both distribution and perturbations of eddy currents at different speeds is detail discussed. The internal and external receiving coils can capture information on magnetic perturbation and eddy currents disturbances, effectively elucidating the impact of the probe velocity. Finally, the superiority of the proposed system was validated through simulation, experimental verification, and real pipe pulling testing.