Article Article
3D Modeling of MFL Imaging System to Detect Surface Discontinuities in Ferromagnetic Tubes

This paper expands on the 3D modeling and simulation of a magnetic flux leakage (MFL) imaging system to detect the different shapes of discontinuities on the surface (outer, sub, and inner) of ferromagnetic steam generator tubes (SGTs). It features an effective detection technique that obtains model-predicted MFL signals for constructing an MFL image of the defective surface to visualize the shape and severity of the discontinuity based on its leakage field. Additionally, the impact of variation in the shape of the discontinuity—such as rectangular, elliptical, or flat-bottom hole (FBH)—on diverse surfaces and its MFL signal is analyzed for enhancing the reliability of determining the characteristics of the discontinuity. The 3D modeling and simulation was performed using a finite element modeling for magnetics (FEMM) tool for predicting the leakage fields of discontinuities found in SGTs.



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