Inspection technology for early detection of small defects in steam generator tubes of sodium-cooled fast reactors.

The 3D eddy current simulation code we developed can accurately simulate complicated steam generator tube shapes. In addition, it is possible to develop an ECT sensor with reasonably high detectability by using high-speed calculation by a supercomputer.

Results of electromagnetic field simulation around a steam generator tube when passing through probe

Developed multi-coil type sensor

We developed the sensor by repeated analysis and testing.

We succeeded in detecting small defects and fatigue cracks with the developed multi-coil type sensor.

Measurement results (ECT)