METHOD TO CONTROL PROPERTIES OF OBJECT FROM ELECTROCONDUCTIVE MATERIALS Russian patent published in 2013 - IPC G01N27/90 

FIELD: measurement equipment.

SUBSTANCE: controlled object is put in reciprocal action with a vortex-current converter (VCC), using an amplitude-phase detector, quadrature components of the VCC signal are defined, and on the basis of the ratio of their values, availability of the useful and unwanted signal is confirmed. At the same time previously hodographs are taken from variation of the gap in the defect-free section of the product and the section containing a calibrating defect. Afterwards the phase of the excitation current is varied so that the signal from the defect matches in direction with one of the axes of coordinates of the complex plane. Afterwards the converter is installed on the controlled object, and availability and relative value of the defect is established on the controlled section, by the relative value of signal increment in direction of the selected axis, from the hodograph corresponding to the defect-free section relative to the calibrating defect signal. The relative value of the gap may be set by the signal increment in orthogonal direction, the selected axis of the complex plane, from the level corresponding to the minimum gap, relative to the signal of the maximum gap. At the same time, through variation of the excitation current phase, the match of defect impact direction may be established with the X-axis or the axis of coordinates.

EFFECT: improved accuracy of monitoring.

3 cl, 2 dwg