Abstract: There is provided an inspection device for inspecting an inner surface of a nozzle provided in a reactor vessel. The inspection device includes: a device frame, an inspection unit provided on the device frame, an inspection unit push-out moving mechanism for pushing out and moving the inspection unit to the inner surface of the nozzle, a rotation moving mechanism for rotating and moving the inspection unit, a calibration test unit arranged on the device frame for calibrating the inspection unit; and a calibration test unit forward/backward moving mechanism for moving the calibration test unit forward or backward in the direction along the central axis with regard to a track where the inspection unit makes push-out movement.

Abstract: An eddy current testing probe includes: exciter coils 2 including a first exciter coil 2a and a second exciter coil 2b identical with each other and arranged in point symmetry, and each of which generates an alternating magnetic field to generate an eddy current in a test object; and detector coils 1 including a first detector coil 1a and a second detector coil 1b identical with each other, arranged in point symmetry, arranged in phase, and differentially connected to each other. The exciter coils 2 and the detector coils 1 are arranged on a single plane. A center of symmetry O on a center line of symmetry CL2 of the coils 2a, 2b, is identical with a center of symmetry O on a center line of symmetry CL1 of the coils 1a, 1b, and the CL1 intersects with the CL2 at a right angle.

Abstract: There is provided an inspection device for inspecting an inner surface of a nozzle provided in a reactor vessel. The inspection device includes: a device frame, an inspection unit provided on the device frame, an inspection unit push-out moving mechanism for pushing out and moving the inspection unit to the inner surface of the nozzle, a rotation moving mechanism for rotating and moving the inspection unit, a calibration test unit arranged on the device frame for calibrating the inspection unit; and a calibration test unit forward/backward moving mechanism for moving the calibration test unit forward or backward in the direction along the central axis with regard to a track where the inspection unit makes push-out movement.

Abstract: There is provided an inspection device for inspecting an inner surface of a nozzle provided in a reactor vessel. The inspection device includes: a device frame, an inspection unit provided on the device frame, an inspection unit push-out moving mechanism for pushing out and moving the inspection unit to the inner surface of the nozzle, a rotation moving mechanism for rotating and moving the inspection unit, a calibration test unit arranged on the device frame for calibrating the inspection unit; and a calibration test unit forward/backward moving mechanism for moving the calibration test unit forward or backward in the direction along the central axis with regard to a track where the inspection unit makes push-out movement.

Abstract: An eddy current testing probe includes: exciter coils 2 including a first exciter coil 2a and a second exciter coil 2b identical with each other and arranged in point symmetry, and each of which generates an alternating magnetic field to generate an eddy current in a test object; and detector coils 1 including a first detector coil 1a and a second detector coil 1b identical with each other, arranged in point symmetry, arranged in phase, and differentially connected to each other. The exciter coils 2 and the detector coils 1 are arranged on a single plane. A center of symmetry O on a center line of symmetry CL2 of the coils 2a, 2b, is identical with a center of symmetry O on a center line of symmetry CL1 of the coils 1a, 1b, and the CL1 intersects with the CL2 at a right angle.

Abstract: There is provided an inspection device for inspecting an inner surface of a nozzle provided in a reactor vessel. The inspection device includes: a device frame, an inspection unit provided on the device frame, an inspection unit push-out moving mechanism for pushing out and moving the inspection unit to the inner surface of the nozzle, a rotation moving mechanism for rotating and moving the inspection unit, a calibration test unit arranged on the device frame for calibrating the inspection unit; and a calibration test unit forward/backward moving mechanism for moving the calibration test unit forward or backward in the direction along the central axis with regard to a track where the inspection unit makes push-out movement.

Abstract: Atmospheric conditions can be efficiently formed within a cavity, and as a result improvements in the operation efficiency within the cavity can be achieved. The operation method is an operation including: a step for detaching a cover in an underwater environment; a step for arranging a fuel rod housing having an upper aperture, in an underwater environment; a step for inserting fuel rods into the fuel rod housing; a step for closing the upper aperture of the fuel rod housing such that it is water-tight; a step for draining water of the cavity; and a step for executing a repair operation on a flange seat surface of a connection part between a container body and the cover in an atmospheric environment.