Steam generator pipe crack detection and measurement method for use in e.g. nuclear power plant, uses Foucault current signals produced by rotating coil of probe inside pipe

摘要

The procedure involves detecting the presence of a crack (2) in a steam generator pipe (1) and measuring its length by measuring the number and positions of inflexion points on a graph of characteristic values of signal amplitudes of Foucault currents generated when a coil of a motorized rotary probe passes in front of the crack is rotated in a spiral motion. The rotary probe coil is flat, or a combination of flat and punctiform, axial or circumferential coils