2013•Yingyong jichu yu gongcheng kexue xuebaoRequires access
3-D FEM Simulation of Lift-Off Effects on Magnetic Flux Leakage Testing
WU Dehu
Open publisher page 0 citations
Abstract
With the increase of pipelines and steel tanks,corrosion leakage accidents happen frequently. The magnetic flux leakage( MFL) method is currently the most commonly used pipeline inspection technique. In this paper,three-dimension( 3-D) finite element analysis has been used to examine the effect of lift-off on MFL signals. Firstly,according to Maxwell equations,the 3-D MFL field distributions of defects were deduced. Then,the 3-D finite element simulation model of MFL under the vibration conditions was established in ANSYS and the MFL signals of defects at different lift-off were analyzed. To confirm the 3-D simulation results,a set of artificial defects was made and the MFL experiments were performed. Finally,the best lift-off at different sizes of defects was achieved by minimizing the errors caused by vibration and electromagnetic noise. This research can be used to optimize the detector structure to increase MFL detection measurement accuracy.