This paper expounds the 3D modelling of the MFL imaging system to monitoring the outer surface defects in Ferro-magnetic Steam Generator Tube (SGT). It features a new flaw detection technique in conjunction with the Magnetic Flux Leakage (MFL) inspection and Digital Imaging. It delivers information of the defective tube surface in the form of a digital image. The impact of variation in the dimension of flaws on the MFL signal is additionally analysed for enhancing the reliability of detection of various defect characteristics. Modelling of MFL imaging system has been done using COMSOL 4. 3 for prediction of leakage fields of defective SGT.

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Magnetic Flux Leakage Steam Generator Tube Digital Imaging Comsol 4. 3 3d Modelling Defect Characterisation.