Abstract: A preventive maintenance/repair device 10 of the present invention includes: a device body 11, and holding mechanisms 13a and 13b connected to the device body 11, the holding mechanisms 13a and 13b being configured to hold the device body 11 on an outer circumferential surface of a cylindrical structure 19. Further, the device body 11 is equipped with a traveling and driving part configured to be circumferentially movable along the outer circumferential surface of the cylindrical structure 19. Furthermore, each of the holding mechanisms 13a and 13b is equipped with a maintenance/repair mechanism 16 configured to maintain and repair the cylindrical structure 19.

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 laser maintenance apparatus including a laser irradiation device which includes a first optical element for irradiating detection laser light on a test object to detect an ultrasonic wave; a second optical element for irradiating generation laser light on a test object so as to excite the ultrasonic wave; and an optical system container for containing the first and second optical element. The reflection direction of the first optical element and the reflection direction of the second optical element are arranged at an angle along the circumferential direction of the test object. The light reflected by the first optical element is irradiated at a position different than light reflected by the second optical element, and the laser irradiation positions of the light reflected by the first and second optical elements are different in the axial direction and the circumferential direction of the test object.

Abstract: According to one embodiment, a laser welding apparatus has a laser irradiation head that is arranged in an outer frame and is divided inside into a light source side and an irradiation side by a partitioning member. The apparatus also has a gas jet nozzle that is formed so as to irradiate a portion to be welded with the laser light and jet the inert gas to the portion to be welded; and a welding wire feed pipe that sequentially feeds a welding wire. The apparatus also has a welding wire contact mechanism that includes a measuring means for measuring a distance between the extremity of the irradiation side and the extremity of the welding wire, and is formed so that the extremity of the welding wire is brought into contact with and pressed against the portion to be welded by an elastic member.

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: According to an embodiment, a horizontally moving stage is mounted on a cylindrical structure within a reactor pressure vessel, travels horizontally along the surface of the cylindrical structure by wheels, and is positioned above an in-reactor pipe by the operation of the horizontally moving stage. A hollow mast is carried by the horizontally moving stage, and is expandable and contractible in a vertical attitude. When the mast is in the vertical attitude, a probe is movable within the mast and performs work in the proximity to the inner surface of the in-reactor pipe. A cable passes through the mast to be connected to the probe.

Abstract: According to an embodiment, an in-reactor operation system which is provided with a crack detection vehicle that moves in a circumferential direction along an outer surface of a shroud disposed in a reactor pressure vessel with the axis vertical, an inspection/check sensor that is mounted on the crack detection vehicle and performs an operation with respect to the shroud, a vehicle positioning mast for setting an initial position of the crack detection vehicle on the shroud, a vehicle fixation mechanism for attaching and detaching the crack detection vehicle to and from the vehicle positioning mast, and a conveyance vehicle for conveying the vehicle positioning mast on which the crack detection vehicle is mounted into the reactor pressure vessel.

Abstract: An apparatus for processing an inside of a pipe which performs various works from an inside of a pipe, includes traveling drive units, a working device, rotation support mechanisms, a coupling mechanism, and suspension devices. The traveling drive units are inserted into the inside of the pipe, and the working device is moved in a circumferential direction along the inside of the pipe by the traveling drive units.

Abstract: According to one embodiment, a laser welding apparatus has a laser irradiation head that is arranged in an outer frame and is divided inside into a light source side and an irradiation side by a partitioning member. The apparatus also has a gas jet nozzle that is formed so as to irradiate a portion to be welded with the laser light and jet the inert gas to the portion to be welded; and a welding wire feed pipe that sequentially feeds a welding wire. The apparatus also has a welding wire contact mechanism that includes a measuring means for measuring a distance between the extremity of the irradiation side and the extremity of the welding wire, and is formed so that the extremity of the welding wire is brought into contact with and pressed against the portion to be welded by an elastic member.

Abstract: According to an embodiment, a submersible electric motor assembly has: a casing; an electric motor that is accommodated in the casing; and an electric insulating substance that is filled between the electric motor and the casing and has a thermal conductivity higher than that of air. The electric motor includes: a stator, a rotor that is rotated by an interaction with a magnetic field of the stator, a coil that magnetizes the stator and/or the rotor, and a shaft that is rotated by rotation of the rotor.

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: A laser maintenance apparatus including a laser system which includes an optical system for emitting, in a first irradiation condition, a generation laser beam for generating an ultrasonic wave in a portion of an object on which maintenance is to be performed, and including a laser source configured to generate and detect a detection laser beam which interacts with the ultrasonic wave generated by the laser light beam in the first condition. The laser maintenance apparatus also includes a light transmitting device for transmitting laser light emitted from the laser system, a laser irradiation device for irradiating laser light transmitted by the light transmitting device to the object portion, and a transporting/scanning mechanism for transporting the light transmitting device and the laser irradiation device to a portion near the object portion, and scanning over an arbitrary range at the object portion.

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: An operation method and apparatus in a pressure vessel of a nuclear reactor is provided. The operation apparatus including a body and a guide inserted from the upper side of the nuclear reactor to an interior of the jet pump. The operation apparatus circulate water inside the pressure vessel. The guide is positioned at the end of a body of the operation apparatus, and is inclined with respect to the center axis of the body so as to be inserted into a side opening of the jet pump.

Abstract: A preventive maintenance/repair device 10 of the present invention includes: a device body 11, and holding mechanisms 13a and 13b connected to the device body 11, the holding mechanisms 13a and 13b being configured to hold the device body 11 on an outer circumferential surface of a cylindrical structure 19. Further, the device body 11 is equipped with a traveling and driving part configured to be circumferentially movable along the outer circumferential surface of the cylindrical structure 19. Furthermore, each of the holding mechanisms 13a and 13b is equipped with a maintenance/repair mechanism 16 configured to maintain and repair the cylindrical structure 19.

Abstract: An operation method and apparatus in a pressure vessel of a nuclear reactor is provided. The operation apparatus including a body and a guide inserted from the upper side of the nuclear reactor to an interior of the jet pump. The operation apparatus circulate water inside the pressure vessel. The guide is positioned at the end of a body of the operation apparatus, and is inclined with respect to the center axis of the body so as to be inserted into a side opening of the jet pump.

Abstract: A laser maintenance apparatus including a laser system which includes an optical system for emitting, in a first irradiation condition, a generation laser beam for generating an ultrasonic wave in a portion of an object on which maintenance is to be performed, and including a laser source configured to generate and detect a detection laser beam which interacts with the ultrasonic wave generated by the laser light beam in the first condition. The laser maintenance apparatus also includes a light transmitting device for transmitting laser light emitted from the laser system, a laser irradiation device for irradiating laser light transmitted by the light transmitting device to the object portion, and a transporting/scanning mechanism for transporting the light transmitting device and the laser irradiation device to a portion near the object portion, and scanning over an arbitrary range at the object portion.

Abstract: A working apparatus has: a working equipment for doing works on a structure; a folding/unfolding mechanism for conveying the working equipment to the working position in a folded state; a conveyance mechanism (such as a horizontal thruster) for conveying the working equipment and the folding/unfolding mechanism to the working position; a pressing mechanism (such as a ballast tank) for pressing the working equipment against the lower surface of the structure; and a traveling mechanism including a wheel for traveling along the lower surface of the structure and positioning the apparatus.

Abstract: An apparatus for processing an inside of a pipe which performs various works from an inside of a pipe, includes traveling drive units, a working device, rotation support mechanisms, a coupling mechanism, and suspension devices. The traveling drive units are inserted into the inside of the pipe, and the working device is moved in a circumferential direction along the inside of the pipe by the traveling drive units.

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.