inducing transverse lines of magnetic force the flux field amplifier is surrounded by a coil which is also energized to make longitudinal lines of force the two types of lines of force are vectored the pipe or other ferromagnetic article is sprayed with uv sensitive magnetic particles in a more or less conventional manner to display the vectored lines of force together with any flaws in the metal the cable core of the flux field amplifier does not need a cooling system and is able to last longer than conventional solid cores application_number US 6433498 A description there are three basic aspects to our invention u2014 the inducement of a magnetic field in one end of the pipe movement of the pipe to an inspection station and the inspection of the magnetized end which takes place in the inspection station the process is repeated for the other end of the pipe in separate magnetizing and inspection stations the inducement of the magnetic field in the pipe takes place in a magnetizing station which is illustrated in fig1 a 1 b and 1 c movement of the pipe from a magnetizing station to an inspection station and provision for inspection of both ends.