EDDY-CURRENT FLAW DETECTOR Russian patent published in 1997 - IPC

FIELD: nondestructive inspection; flaw inspection of current-conducting equipment. SUBSTANCE: eddy-current transducer 1 has C-shaped core 2 with winding 3 and sensing element 4 formed by two inductance coils placed inside each other and connected differentially. Transducer is characterized in that it has high selective sensitivity to continuity flaws. Phase of recorded voltage built up due to flaw varies by tens of degrees. In case of misalignment of this transducer axis, on the contrary, phase of built up voltage varies by maximum a few degrees. Amplitude-phase selection unit 25 functions to suppress signals arriving at this angle sector. In addition, compensation is provided in manual and automatic modes by means of self-compensation unit using quadrature components and built around proportional-integral regulators with feedback disconnected in manual mode by means of switches 30, 31. EFFECT: improved validity of inspection. 5 cl, 6 dwg