The components of the magnetic field of a steel pipe, which is described by the field of a dipole thread, are considered. The calculated model of the pipe field with a defect is constructed. The quantitative results of calculations of deformation distributions of field components caused by various defects and for various orientations of the primary excitation field are presented and analyzed. It is shown that the normal (radial) component of the deformed magnetic field is 5 times greater than the tangential (azimuthal) component. The obtained results can be used to assess the capabilities and development of methods and means for remote detection and determination of defects parameters of the steel pipe.

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