Abstract: The present invention provides an underwater moving vehicle improved in motion performance and capable of stably maintaining its position. [Solution] An underwater moving vehicle comprising: a vehicle body (1) configured to be set in advance in such a manner that weight of the vehicle body (1) becomes larger than buoyant force generated in water; a thruster (32) configured to generate an upward thrust by driving screw propellers (21); a drive adjuster (50) configured to control water depth of the vehicle body (1) to a predetermined position by adjusting drive of the screw propellers (21) and generating the upward thrust equivalent to difference between the weight and the buoyant force; and a water flow deflector (34) configured to move the vehicle body (1) in a horizontal direction by deflecting a downward water flow generated by the screw propellers (21).

Abstract: A control rod/fuel support handling apparatus that is used in the case where a control rod and a fuel support are held, removed and lifted in a reactor and then are transported into the reactor in a periodical inspection of a BWR and in the case where the control rod and the fuel support are attached and mounted again into the reactor, the control rod/fuel support handling apparatus including: a fuel support gripper that holds the fuel support with a support gripping member; a control rod gripper that includes a vertically movable and rotatable elevating/rotating unit, holds the control rod with a control rod gripping member, disconnects and connects the control rod and a control rod drive mechanism, and allows removal and attachment of the control rod; and a control panel that controls automatically controls the control rod gripper in response to the instructions from an operation pendant.

Abstract: A cleaning apparatus is generally composed of a suction unit provided with a suction source, a suction nozzle equipped with a suction port adapted to suck dust or like from a surface to be cleaned, a suction hose connected at one end to the suction nozzle and connected at another end to the suction unit, a low-center-of-gravity support member provided for the suction hose so as to serve as a fulcrum when the suction hose is bent and deformed, a wire member supported at a distal end by the suction nozzle and arranged along the suction hose, and a control unit used to bend and deform the suction hose by manipulating the wire member with the low-center-of-gravity support member serving as a fulcrum. This cleaning apparatus is specifically usable for a bottom surface of a reactor pressure vessel.

Abstract: A control rod/fuel support handling apparatus that is used in the case where a control rod and a fuel support are held, removed and lifted in a reactor and then are transported into the reactor in a periodical inspection of a BWR and in the case where the control rod and the fuel support are attached and mounted again into the reactor, the control rod/fuel support handling apparatus including: a fuel support gripper that holds the fuel support with a support gripping member; a control rod gripper that includes a vertically movable and rotatable elevating/rotating unit, holds the control rod with a control rod gripping member, disconnects and connects the control rod and a control rod drive mechanism, and allows removal and attachment of the control rod; and a control panel that controls automatically controls the control rod gripper in response to the instructions from an operation pendant.

Abstract: A method of computing an operating position based on a relative distance between a monitor and a movable body correlating data is obtained in advance for determining a one to one correlation between the relative distance and dimensions on the surface of a photographed object of an image. A relative angle is measured between the photographed object and the monitor. The movable body is photographed using a camera of the monitor. The distance and dimensions between reference points on the image are compared with the correlating data coincident with the measured relative angle.

Abstract: A method of computing an operating position based on a relative distance between a monitor and a movable body correlating data is obtained in advance for determining a one to one correlation between the relative distance and dimensions on the surface of a photographed object of an image. A relative angle is measured between the photographed object and the monitor. The movable body is photographed using a camera of the monitor. The distance and dimensions between reference points on the image are compared with the correlating data coincident with the measured relative angle.

Abstract: A cleaning apparatus is generally composed of a suction unit provided with a suction source, a suction nozzle equipped with a suction port adapted to suck dust or like from a surface to be cleaned, a suction hose connected at one end to the suction nozzle and connected at another end to the suction unit, a low-center-of-gravity support member provided for the suction hose so as to serve as a fulcrum when the suction hose is bent and deformed, a wire member supported at a distal end by the suction nozzle and arranged along the suction hose, and a control unit used to bend and deform the suction hose by manipulating the wire member with the low-center-of-gravity support member serving as a fulcrum. This cleaning apparatus is specifically usable for a bottom surface of a reactor pressure vessel.

Abstract: A protection plate is welded to a metal structure in water so that the protection plate covers the surface of the structure including a portion to be repaired. The welding is carried out such that the periphery of the protection plate is welded in water by laser welding while inactive gas is supplied to portion to be welded to seal the portion to be repaired by the protection plate. Welding is carried out while the inactive gas is supplied to the portion to be welded coaxially with a laser beam during the laser welding. The plate is provided therein with an opening in advance so as to release vapor produced from water remaining during welding between the protection plate and the structure and the opening is sealed after the periphery of the protection plate is welded to the structure.

Abstract: Disclosed is a system that performs inspection and repair of an underwater structure, specifically core internals in a pressure vessel. An underwater vehicle is provided with a drive wheel, a contact force generating unit (e.g., thruster) that presses the drive wheel to a vertical wall of the underwater structure, an ascending force control unit (e.g., ballast) that controls the buoyancy of the vehicle, a guide roller that engages with and is pressed against an undersurface of the underwater structure by the ascending force controlled by the ascending force control unit. The underwater vehicle is appropriately positioned with respect to the vertical direction by the guide roller. The drive wheel is driven for rotation so that the underwater vehicle runs horizontally along the vertical wall to reach the inspection or repair site, where the inspection or repair is carried out by work tool mounted to the underwater vehicle.

Abstract: Disclosed is a system that performs inspection and repair of an underwater structure, specifically core internals in a pressure vessel. An underwater vehicle Is provided with a drive wheel, a contact force generating unit (e.g., thruster) that presses the drive wheel to a vertical wall of the underwater structure, an ascending force control unit (e.g., ballast) that controls the buoyancy of the vehicle, a guide roller that engages with and Is pressed against an undersurface of the underwater structure by the ascending force controlled by the ascending force control unit. The underwater vehicle is appropriately positioned with respect to the vertical direction by the guide roller. The drive wheel Is driven for rotation so that the underwater vehicle runs horizontally along the vertical wall to reach the inspection or repair site, where the inspection or repair is carried out by work tool mounted to the underwater vehicle.

Abstract: There are provided a control rod holding unit 16 for releasably holding a control rod 7 which is loaded in a reactor vessel 1, and fuel support/control rod guide tube holding unit 17 for releasably holding a fuel support 8 which supports a bottom end of a fuel assembly 10 and a control rod guide tube 6 on which the fuel support 8 is placed at top end. The control rod holding unit 16 and the fuel support/control rod guide tube holding unit 17 are fitted to a main body frame 26 which can be hoisted down inside the reactor vessel 1. Accordingly, there can be provided a reactor-internal equipment handling apparatus and method which are capable of reducing a term of work which is required for operations to load/unload the control rods, the fuel supports, and the control rod guide tubes.

Abstract: A control rod/fuel support grapple is provided which is capable of pulling up simultaneously a control rod and a fuel support from a reactor and also uncoupling the control rod and control rod drive mechanism. The control rod/fuel support grapple comprises a control rod holding unit for holding a control rod's hoist handle, a fuel support holding unit for holding a fuel support, and a coupling releasing unit or uncoupling the control rod and the control rod drive mechanism, coupled by virtue of a spud coupling. These three units are attached to a main body frame which is lowered into a reactor pressure vessel.

Abstract: There are provided a control rod holding unit 16 for releasably holding a control rod 7 which is loaded in a reactor vessel 1, and fuel support/control rod guide tube holding unit 17 for releasably holding a fuel support 8 which supports a bottom end of a fuel assembly 10 and a control rod guide tube 6 on which the fuel support 8 is placed at top end. The control rod holding unit 16 and the fuel support/control rod guide tube holding unit 17 are fitted to a main body frame 26 which can be hoisted down inside the reactor vessel 1. Accordingly, there can be provided a reactor-internal equipment handling apparatus and method which are capable of reducing a term of work which is required for operations to load/unload the control rods, the fuel supports, and the control rod guide tubes.

Abstract: A reactor-internal equipment handling apparatus which is capable of reducing work required to load/unload control rods, fuel supports, and control rod guide tubes, includes a control rod holding unit (16) for releasably holding a control rod (7) which is loaded into a reactor vessel (1), and fuel support/control rod guide tube holding unit (17) for releasably holding a fuel support (8) which supports a bottom end of a fuel assembly (10) and a control rod guide tube (6) on which the fuel support (8) is placed. The control rod holding unit (16) and the fuel support/control rod guide tube holding unit (17) are fitted to a main body frame (26) which can be hoisted down inside the reactor vessel (1).