L. K. Kogan, A. N. Stashkov

THE EFFECT OF THE ELECTRICAL RESISTIVITY OF CONDUCTIVE COPPER CONNECTIONS ON THE RELIABILITY OF TESTING THE SOLDERING QUALITY OF CLAMP SIDE WALLS BY THE AMPLITUDE EDDY CURRENT METHOD

A transformer eddy-current transducer with rectangular notches in the poles of its U-shaped core is used to study the effect of a change in electrical resistivity of M1 copper within the range between 0.01724 and 0.01748 μΩ∙m according to GOST 193-79 and GOST 1173-2006 on the error in determining the soldering quality of the side walls of clamps with lead ends of current-carrying rods, which are used to connect stator windings in state-of-the-art designs of hydro- and turbogenerators. Specimens made at different times and received from different power engineering enterprises are studied. It is found that, when the relative difference of electrical resistivity varies within 1.36%, the error in evaluating the level of soldering of the side walls of clamps does not exceed 15.5%. This must be taken into account when performing eddy current testing.

Acknowledgment: The work was performed under the state assignment from the Russian Ministry of Science and Higher Education (theme Diagnostics, No 122021000030-1).

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