Capabilities of eddy current ndt of soldered current-carrying joints in submersible electrical equipment

The paper shows the possibility to test the quality of soldering of small current-carrying non-ferromagnetic joints in submersible electrical equipment for oil and gas systems by the amplitude eddy current method using a highly sensitive primary transducer with a U-shaped core. The sensitivity of soldering quality testing under different conditions of generating an exciting signal is compared. It has been found that the sensitivity of NDT in the case of current amplitude stabilized in the excitation coil (current generator) is significantly higher than that in case of voltage amplitude stabilized in it (voltage generator). Possible errors in determining the level of soldering of the joints due to the variation of their cross section within the limits of tolerance according to the technology of their manufacture have been detected. Circuit solutions and software have been developed to test the level of soldering of such joins. Approbation of soldering quality testing was carried out on products manufactured under production conditions.