Abstract: The present invention is a control rod guide tube cleaning apparatus in a nuclear reactor which includes a rod member, one end side portion of which has a thickness such that the end side portion can pass through the inside of a connecting portion between a housing of a control rod drive mechanism and a control rod guide tube, a nozzle for sucking water, mounted on the rod member on the one end side so that the nozzle can go in and out of the rod member, a means for rotating the rod member in a horizontal direction, and a water passage for leading water sucked in the nozzle to an outside of the housing along the rod member. The rod member is inserted into the control rod guide tube through the inside of the housing. Then, the nozzle is rotated downward so that a suction port of the nozzle faces the bottom inside portion of the control rod guide tube for the suction of dust and debris. The nozzle is rotated in the horizontal direction by rotating the rod member in the horizontal direction.

Abstract: The present invention is a control rod guide tube cleaning apparatus in a nuclear reactor which comprises a rod member, one end side portion of which has the thickness such that the end side portion can pass through an inside of a connecting portion between a housing of a control rod drive mechanism and a control rod guide tube, a nozzle for sucking water, mounted on the rod member on the one end side so that the nozzle can go in and out of the rod member, a means for rotating the rod member in a horizontal direction, and a water passage for leading water sucked in the nozzle to an outside of the housing along the rod member. The rod member is inserted into the control rod guide tube through the inside of the housing. Then, the nozzle is rotated downward so that a suction port of the nozzle faces adjacently to the bottom inside the control rod guide tube. The nozzle is rotated in the horizontal direction by rotating the rod member in the horizontal direction.