Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 52 3 2018 11 20 Study on the Influence of Spacing of the Nearby Corrosion Defects on Magnetic Flux Leakage Signals Study on the Influence of Spacing of the Nearby Corrosion Defects on Magnetic Flux Leakage Signals 619 634 3129 10.22060/mej.2018.14406.5849 FA Turaj Azizzadeh Department of mechanical engineering,Iran university of science and technology, Tehran, Iran Mir Saeed Safizadeh Department of mechanical engineering, Iran university of science and technology, Tehran, Iran Journal Article 2018 05 04 Magnetic flux leakage technique is a widely used and effective approach for detecting and sizing of the corrosion defects in ferromagnetic pipelines. In general, corrosion defects occur in dense clusters and affect each other. However due to the interaction between the magnetic flux leakage signals, these defects can-not be accurately characterized using the traditional magnetic flux leakage method. In order to discriminate the individual defects and improve sizing performance, tri-axial magnetic flux leakage technique is used. The study is performed using the extensive finite element modeling focusing on the spatial distribution of tri-axial magnetic flux leakage components produced by the nearby corrosion defects. This type of defect geometry comprises two pits that are sufficiently close to influence flux distributions in the area between them. Various degrees of closeness are considered by varying the spacing of the two pits. Following the simulations, experimental magnetic flux leakage tests are performed on the steel plates containing nearby pits. The experimental and finite element modeling results indicate that combining the axial, radial and tangential magnetic flux leakage data can discriminate and characterize the nearby pits. Finally, the experimental and finite element modeling results are compared and validated. Magnetic flux leakage technique is a widely used and effective approach for detecting and sizing of the corrosion defects in ferromagnetic pipelines. In general, corrosion defects occur in dense clusters and affect each other. However due to the interaction between the magnetic flux leakage signals, these defects can-not be accurately characterized using the traditional magnetic flux leakage method. In order to discriminate the individual defects and improve sizing performance, tri-axial magnetic flux leakage technique is used. The study is performed using the extensive finite element modeling focusing on the spatial distribution of tri-axial magnetic flux leakage components produced by the nearby corrosion defects. This type of defect geometry comprises two pits that are sufficiently close to influence flux distributions in the area between them. Various degrees of closeness are considered by varying the spacing of the two pits. Following the simulations, experimental magnetic flux leakage tests are performed on the steel plates containing nearby pits. The experimental and finite element modeling results indicate that combining the axial, radial and tangential magnetic flux leakage data can discriminate and characterize the nearby pits. Finally, the experimental and finite element modeling results are compared and validated. https://mej.aut.ac.ir/article_3129_c6a01432c8138d46ba39957a8250e027.pdf