An eddy-current flaw detection device is provided thatimproves spatial resolution of flaw detection signals and signalreproducibility during redetection of flaws, and reducesinterference signals with simple circuit construction.The eddy-current flaw detection device comprises amagnetic element group of which a specified number of magneticelements are evenly spaced in each of at least two rows that areformed around the surface of a column shaped casing that isformed such that it can be inserted into a conductive pipe (notshown in the figures), with one row 11 to 18 being located at aposition that differs from the other row 21 to 28 by 1/2 the evenspacing in the row direction, and switching circuits for switchingthe magnetic elements in the respective row of the magneticelement group at time-division. The magnetic elements 11 to 18 ofone row function as magnetic field excitation elements that excite amagnetic field by being switched at time-division, the magneticelements 21 to 28 of the other row function as magnetic fielddetection elements that detect a magnetic field by being switchedat time-division, and the eddy-current flaw detection deviceperforms eddy-current flaw detection of the conductive pipe bydetecting each magnetic field that is excited by each magnetic fieldexcitation element 11 to 18 by two magnetic field detectionelements 21 to 28 that are each located at positions that differsfrom the magnetic field excitation elements 11 to 18 by 3/2 the evenspacing in the row direction.
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