JPH08146186A - Nuclear reactor internal structure inspection device and inspection method - Google Patents

Abstract

PURPOSE: To prevent a cable from being caught, getting entangled, or colliding with an obstacle, and to reduce the approach time to a narrow part by reducing the traveling distance of an underwater vehicle to approach a target testing part. CONSTITUTION: While an underwater vehicle 4 is swum in the water by remote operation, a visual examination for a nuclear reactor internal structure is performed. A container 7 stores the underwater vehicle 4 and is provided with an opening part 11 through which the underwater vehicle 4 goes in and out. The inspection device comprises a moving means 3 for moving the container to the vicinity of a target testing part of a nuclear internal structure and installing the same, and a holding means 12 for holding the underwater vehicle 4 in the container 7. At the time of inspection, the holding means 12 is released to start the underwater vehicle 4 from the opening part 11 of the container 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention visually inspects the integrity of internal structures such as jet pumps, core shroud walls, reactor pressure vessel walls and shroud support plates located in the reactor annulus section of a nuclear power plant. The present invention relates to a nuclear reactor internal structure inspection device and inspection method.

[0002]

2. Description of the Related Art Conventionally, when performing visual observation in water by remote control, such as in a nuclear facility, it has been common to use a fixed camera or a camera provided on a moving body along an orbit.

However, since these devices have a drawback that they can see only a certain portion and the inspection range is restricted, in recent years, an inspection device which is equipped with a camera and can freely move in water is being developed. . In this inspection device, for example, a pressure-resistant casing equipped with a visual observation camera and a lighting device is provided with a propulsion mechanism and attitude control means to form an underwater vehicle. It is designed so that a visual inspection can be conducted by swimming in water while pulling the cable around.

[0004]

However, since there are many narrow parts inside the nuclear reactor and the like, when inspecting the internal structure of the reactor with the above-mentioned underwater vehicle, while the underwater vehicle moves to the inspected part, the cable There is a problem that it takes a long time to approach the narrow space and is required to be skilled in operation, because it is caught in the furnace internal structure, entangled, or collides with an obstacle.

The present invention has been made in view of the above circumstances, and shortens the traveling distance of the underwater vehicle until the target inspection portion is approached, so that the cable is not caught or entangled, or to an obstacle. Prevent the collision of
It is an object of the present invention to provide a reactor internal structure inspection device and inspection method capable of shortening the approach time to a narrow space.

[0006]

According to a first aspect of the present invention, an underwater vehicle is constructed by providing a propulsion mechanism and an attitude control means in a pressure-resistant casing equipped with a camera for visual observation and a lighting device, and the underwater vehicle is remote. In a nuclear reactor internal structure inspection device configured to visually inspect a nuclear reactor internal structure while swimming in water by operation, a storage container for accommodating the underwater vehicle and forming an opening through which the underwater vehicle comes in and out. , A moving means for moving and installing this storage container in the vicinity of the intended inspection site of the reactor internal structure, and a holding means for holding the underwater vehicle in the storage container, and releasing this holding means at the time of inspection. The underwater vehicle is started from the opening of the storage container.

According to a second aspect of the present invention, in the in-reactor internal structure inspection apparatus according to the first aspect, a cable guide mechanism for paying out and winding up the cable of the underwater vehicle is provided inside the storage container. Characterize.

A third aspect of the present invention is characterized in that the cable guide mechanism according to the second aspect has a drive motor, and an encoder for detecting a cable feeding distance is attached to the drive motor.

According to a fourth aspect of the present invention, in the nuclear reactor internal structure inspection apparatus according to the first or second aspect, a television camera for monitoring the underwater vehicle is arranged in the storage container.

According to a fifth aspect of the present invention, in the nuclear reactor internal structure inspection apparatus according to the first, second or fourth aspect, the storage container is provided with a traveling means for moving the upper end portion after the core shroud is installed. .

According to a sixth aspect of the present invention, in the reactor internal structure inspection apparatus according to the fifth aspect, the traveling means is provided with a traveling distance detector for detecting a traveling distance, and the traveling distance detection signal is sent to the signal processing device. It is characterized in that the signal is taken in, compared with a signal at a preset position in this signal processing device, and the signal processing result is sent as a drive signal to the traveling means.

A seventh aspect of the present invention is the nuclear reactor internal structure inspection apparatus according to the first, second, fourth, or fifth aspect, wherein the storage container comprises:
It is characterized in that a guide device for guiding the underwater vehicle to a target inspection site is attached.

According to an eighth aspect of the present invention, in the nuclear reactor internal structure inspection apparatus according to the first, second, fourth, fifth or seventh aspect, the storage container has a fixing portion for attaching to and detaching from the nuclear reactor internal structure. Is characterized by.

According to a ninth aspect of the present invention, in the nuclear reactor internal structure inspection apparatus according to the first, second, fourth, fifth or seventh aspect, the storage container is provided with a seating portion capable of sitting on an obstacle at a target inspection site. Is characterized by.

According to a tenth aspect of the present invention, an internal structure of a nuclear reactor is provided while a submersible vehicle having a pressure-resistant casing equipped with a visual observation camera and an illuminating device and provided with a propulsion mechanism and an attitude control means is remotely operated to swim in water. In the nuclear reactor internal structure inspection method adapted to perform the visual inspection, the storage container for storing the underwater vehicle is moved and installed near the target inspection site of the nuclear reactor internal structure, and then the underwater vehicle is held. It is characterized in that the holding means is released and the underwater vehicle is started from the opening formed in the storage container to perform the inspection.

[0016]

According to the first aspect of the present invention, a storage container for storing an underwater vehicle and having an opening through which the underwater vehicle enters and exits, and the storage container is moved and installed in the vicinity of a target inspection site of the reactor internal structure. By having the moving means and the holding means for holding the underwater vehicle in the storage container, the moving means moves the storage container near the target inspection site of the reactor internal structure and then holds the underwater vehicle. Release the holding means, activate the propulsion mechanism and attitude control means of the underwater vehicle, start the underwater vehicle from the opening of the storage container, and levitate, dive, advance, retract, turn, etc. to approach the target inspection site. , Visual inspection is carried out by the mounted visual observation camera and lighting device. As a result, the running distance of the underwater vehicle is short, the cables do not get entangled or caught while moving to the intended inspection site of the reactor internals, and the possibility of collision with obstacles is also reduced. However, it is possible to shorten the approach time to the narrow space.

Further, by providing the holding means for holding the underwater vehicle in the storage container, even if an unexpected situation occurs, it is possible to prevent the underwater vehicle from jumping out of the storage container and store the underwater vehicle. It can be reliably stored and held in the container.

According to the second aspect of the present invention, the cable guide mechanism for paying out and winding up the cable of the underwater vehicle is provided inside the storage container, so that the interference of the cable with the structure can be prevented and the swimming movement of the underwater vehicle can be prevented. The operability can be improved without hindering.

According to another aspect of the present invention, the cable guide mechanism has a driving motor, and the encoder for detecting the cable feeding distance is attached to the driving motor, so that the underwater vehicle moves from the cable feeding distance. Knowing the distance makes it easier to control the underwater vehicle.

According to the present invention, since the television camera for monitoring the underwater vehicle is provided in the storage container, it becomes easy to confirm the position of the underwater vehicle and the state of the cable.
The underwater vehicle will be easier to control.

According to the present invention, since the storage container is provided with the traveling means for moving the upper end portion of the core shroud after the core shroud is installed, the storage container can be easily moved to a place where there is no obstacle. As a result, the movement distance of the underwater vehicle is small, and the cable is not entangled or caught while moving to the target inspection site.

According to a sixth aspect of the present invention, the traveling means is provided with a traveling distance detector for detecting a traveling distance, the traveling distance detection signal is taken into a signal processing device, and a signal of a position preset by the signal processing device is obtained. By comparing and sending the signal processing result to the traveling means as a drive signal,
Since the storage container can be automatically moved to the vicinity of the designated target inspection site, the storage container can be moved in a short time.

According to the present invention, a guide device for guiding the underwater vehicle to the target inspection site is attached to the storage container, thereby avoiding the risk of the underwater vehicle colliding with an obstacle, and placing the underwater vehicle at the target test site. It can be guided in a short time.

In the present invention, since the storage container is provided with the fixing portion for attaching to and detaching from the reactor internal structure, the underwater vehicle is started while the storage container is securely fixed to the reactor internal structure, Can be stored. As a result, it is possible to stably start and store the underwater vehicle.

In the present invention, the storage container is provided with the seating portion capable of seating on the obstacle at the target inspection site.
The storage container is seated on the obstacle at the target inspection site, and the underwater vehicle is started from there to approach the target inspection site for visual inspection. As a result, the cable is not entangled or caught before the underwater vehicle moves to the target inspection site, and the risk of collision with an obstacle can be avoided.

According to the tenth aspect of the present invention, after the storage container for storing the underwater vehicle is moved and installed in the vicinity of the target inspection site of the reactor internal structure, the holding means for holding the underwater vehicle is released to form the storage container. The inspection efficiency can be improved and the inspection time can be shortened by starting the underwater vehicle from the opening and performing the inspection.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall construction of a first embodiment of the nuclear reactor internal structure inspection apparatus according to the present invention, and FIG. 2 shows a state in which the storage container shown in FIG. 1 is installed at the upper end of the core shroud. It is a block diagram. As shown in FIG. 1, a refueling machine 2 is installed on the operation floor 1, and the refueling machine 2 is always equipped with a mast 3 as a moving means. Further, the reactor internal structure inspection apparatus of this embodiment is shown in FIG.
The underwater vehicle 4, a control device 5 installed on the operation floor 1 for remotely operating the underwater vehicle 4, and a cable 6 for electrically connecting them are roughly classified as shown in FIG.
And a storage container 7 that stores the underwater vehicle 4 and is suspended from the mast 3 and installed near the target inspection site.

As shown in FIG. 3, this container 7 is installed in the reactor pressure vessel 8 at the upper end of the core shroud 10 while avoiding the core shroud head bolt bracket 9 which is an obstacle at the visual inspection site. To be done. At the bottom of the storage container 7, an opening 1 through which the underwater vehicle 4 enters and exits
1, a hinged door 12 as a holding means for holding the underwater vehicle 4 is disposed inside the opening 11, and the hinged door 12 includes a cylinder driven by air pressure or hydraulic pressure. It is operated by the holding mechanism driving device 13, and by driving the holding mechanism driving device 13,
The underwater vehicle 4 can be held or opened and stored or started in the storage container 7.

A cable guide mechanism 14 for paying out and winding up the cable 6 is arranged in the storage container 7, and the cable guide mechanism 14 is a pair of pulleys made of a rubber pulley or a brush pulley. 15, 1
6, and these pulleys 15 and 16 are rotationally driven by a drive motor 17 attached to the pulley 15. The pulleys 15 and 16 gently push the cable 6 while feeding and winding the cable 6. In addition, the cable 6 can be pulled from above the operation floor 1 should the drive motor 17 fail. The operation of the cable guide mechanism 14 is confirmed by the television camera 18 arranged in the vicinity thereof. And
An encoder (not shown) is attached to the drive motor 17 to detect the feeding distance of the cable 6.

Further, a guiding device 19 for guiding the underwater vehicle 4 is fixed to a side portion of the storage container 7, and the guiding device 19 rotatably drives the laser light generating device and the laser light generating device. It has a built-in rotation motor. A television camera 20 and a lighting device 21 are provided inside the storage container 7. The television camera 20 confirms whether or not the television camera 20 is stored in the storage container 7 during the storage operation of the underwater vehicle 4, and guides the guide device 19. This is for confirming the guide beam GB emitted from the laser beam generator, and the underwater vehicle 4 is self-propelled to the target inspection site while confirming the guide beam GB. A television camera 22 is provided near the guiding device 19 fixed to the side of the storage container 7. The television camera 22 is rotatably driven by a drive motor 23 that can be operated remotely, and the television camera 22 guides the beam. The situation of the GB and the underwater vehicle 4 can be grasped. A grip portion 24 for suspending the mast 3 by the grip mechanism is attached to the upper portion of the storage container 7.

On the other hand, as shown in FIG. 4, the storage container 7 has a plurality of running wheels 2 coated with a high friction material such as hard rubber.
5, the traveling wheel 25 is operatively connected to the drive motor 27 through the shaft portion and the power transmission mechanism 26, and the traveling wheel 25 has the storage container 7 through the shaft portion.
A mileage detector 28 for detecting the position of the vehicle is attached. In addition, the storage container 7 has an auxiliary traveling wheel 29 that forms a pair with the traveling wheel 25, and the auxiliary traveling wheel 29 is rotatably attached to the fixed portion 30. The fixed portion 30 is operated by air pressure or hydraulic pressure. By expanding and contracting the rod of the operating cylinder 31, the storage container 7 can be attached to and detached from the upper end portion of the core shroud 10. Further, a driven wheel 32 that is driven and rotated by the traveling wheel 25 is installed at the bottom of the storage container 7. Then, the storage container 7 is placed in the core shroud 1
When the drive motor 27 is operated when mounted on the upper end portion of 0, the traveling wheels 25 rotate via the power transmission mechanism 26, and the storage container 7 self-propels on the upper end portion of the core shroud 10.

The underwater vehicle 4 of this embodiment is constructed as shown in FIG.

That is, as shown in FIG. 5, the underwater vehicle 4 has a pressure resistant casing 34 which is substantially spherical and partially transparent.
A front and rear direction propulsion mechanism 35, a vertical direction propulsion mechanism 36, a balance weight 37 as an attitude control means, a movable television camera 38 for visual observation, an illumination device 39, etc. are mounted.

In order to facilitate the explanation, FIG.
5 is a basic posture, a portion where the TV camera 38 is arranged (left side portion in FIG. 5) is a front portion, and a portion where the forward-backward propulsion mechanism 36 is arranged (right side portion in FIG. 5) is a rear portion,
Further, the up / down and left / right directions will be described with the front part viewed from the rear part.

The pressure-resistant casing 34 includes a plurality of vertically split elements, for example, a center frame 34a located at the center.
And a pair of left and right side frames 34b sandwiching this, and a television camera 38 is attached to the center frame 34a.
a pair of front-back propulsion mechanism 35 and vertical propulsion mechanism 3 in b
6, a balance weight 37, a lighting device 39, etc. are attached. TV camera 38 and lighting device 3
The front portion of the pressure resistant casing 34 that covers 9 is made of transparent pressure resistant glass.

The pair of front-rear propulsion mechanisms 35 can be driven independently of each other, and the jet speed is controlled by changing the rotational speed or the rotational direction, so that the left-right turning can be performed in the forward-backward movement or in the stopped state. It has become. The up-down direction propulsion mechanism 36 is arranged such that the propulsion axis of the front-rear direction propulsion mechanism 35 is orthogonal to that of the side frame 3
4b. As shown in FIG. 5, the balance weights 37 are flat plate-shaped and have a swelled lower portion and form a substantially triangular shape, and a pair of balance weights 37 are arranged on the left and right outer surfaces of the casing 34. The movable television camera 38 for visual observation can change its direction in the vertical direction at the front part of the casing 34. A plurality of lighting devices 39 are disposed on the left and right sides of the television camera 38 and are arranged on the side frame 34a.

FIG. 6 is a block diagram showing the control system for the underwater vehicle 4, the control device 5, and the storage container 7. As shown in FIG. 6, the drive motor 27 is operated to drive the power transmission mechanism 26.
When the traveling wheels 25 are rotated through the core, the core shroud 1
The storage container 7 is self-propelled with respect to the upper end portion of 0. The distance traveled by the storage container 7 is taken into the signal processing device in the control device 5 as the travel distance detection signal 41 from the travel distance detector 28. The control device 5 compares the signal of the preset position of the storage container 7 and sends the signal processing result to the drive motor 27 as a drive signal 42.
Pre-set underwater vehicle start / storable position 43
(Shown in FIG. 7), the opening / closing mechanism drive signal 45 is sent to the holding mechanism drive device 13 via the solenoid valve 44,
The hinged door 12 is opened and the underwater vehicle 4 is started.

Further, a water depth detector (pressure sensor) 46 is mounted on the underwater vehicle 4, the water depth distance is detected by the water depth detector (pressure sensor) 46, and the water depth distance signal 47 is a signal in the control device 5. The water depth of the underwater vehicle 4 is adjusted by being taken into the processing device. Further, in order to move the underwater vehicle 4 to the water depth distance of the preset target inspection site, the controller 5 sends the propulsion device drive signal 4
8 is sent to the vertical propulsion mechanism 36 for ascending and submerging the underwater vehicle 4. Here, in the underwater vehicle 4, a direction detector (not shown) and a gyro (tilt detector) for detecting a rotation angle of the underwater vehicle 4 are attached inside,
The direction detection signal and the rotation angle signal of the underwater vehicle 4 detected by the direction detector and the gyro are taken into the control device 5. Then, in order to make the underwater vehicle 4 stand still in the direction in which the visual inspection is performed, the propulsion device drive signal 48 processed by the control device 5 is sent to the forward / backward propulsion mechanism 35 for advancing and reversing the underwater vehicle 4. Control the number of rotations.

Next, the operation of this embodiment will be described.

When the in-reactor internal structure inspection apparatus of the present embodiment is used, for example, as shown in FIG. 1, on the operation floor 1, the storage container 7 storing the underwater vehicle 4 is moved by the moving means of the fuel exchanger 2. It is hung on the mast 3 which is. Then, the mast 3 is extended downward to gradually lower the storage container 7, and the mast 3 is installed on the upper end portion of the core shroud 10 in the reactor pressure container 8 as shown in FIGS. 2 and 3.
After the storage container 7 is installed, the grip mechanism of the mast 3 is released from the grip portion 24 of the storage container 7 to store the mast 3.

Next, the control device 5 is operated to drive the drive motor 27, and the traveling wheel 25 is rotated by this drive force via the power transmission mechanism 26 to travel the storage container 7 to the upper end portion of the core shroud 10. Then, as shown in FIG. 7, the vehicle is moved to the underwater vehicle starting / storing position 43. Here, the underwater vehicle start / storing position 43 from the operation floor 1
When transporting the underwater vehicle 4 up to this point, the hinged door 12 provided in the storage container 7 is closed to hold the underwater vehicle 4.

Then, as shown in FIG. 6, the control device 5 is operated to send an opening / closing mechanism drive signal 45 to the holding mechanism drive device 13 via the solenoid valve 44, whereby the hinged door 12 is opened and the underwater vehicle 4 is opened. Will start. The underwater vehicle 4 approaches the target inspection site by operating the longitudinal propulsion mechanism 35 and the vertical propulsion mechanism 36 while detecting the water depth, the direction and the rotation angle of the underwater vehicle 4 by the water depth detector 46, the direction detector and the gyro. Then, visual inspection is carried out by the mounted television camera 38 for visual observation and the illuminating device 39. Here, the feeding of the cable 6 is performed by operating the control device 5 to drive the drive motor 17 and rotating the pulleys 15 and 16.

Further, when the underwater vehicle 4 is collected in the storage container 7, the drive motor 17 is driven to drive the pulley 1
While rotating 5 and 16 to wind up the cable 6, the underwater vehicle 4 is raised and put into the storage container 7. Then, after confirming with the television camera 20 whether or not the underwater vehicle 4 is stored in the storage container 7, the holding mechanism driving device 13
And the hinged door 12 is closed to store the underwater vehicle 1.

As described above, according to the present embodiment, the underwater vehicle 4 is stored in the storage container 7 so as to be able to move in and out, and the storage container 7 is arranged in the vicinity of the inspection portion of the in-core structure. The traveling distance of 4 is short, the cable 6 does not get entangled or caught while moving to the target inspection site, the possibility of collision with an obstacle is reduced, and the approach time to the narrow space is reduced. It can be shortened. Further, by operating the control device 5, the burden on the operator is reduced because the control is automatically performed. Further, even when the underwater vehicle 4 is recovered in the event of a failure, the underwater vehicle 4 can be recovered while checking the state of the underwater vehicle 4 by the television camera 22, so that the underwater vehicle 4 can be easily recovered in a short time.

The opening 1 from which the underwater vehicle 4 starts
1 is formed on the bottom of the storage container 7, the opening 1
Since the underwater vehicle 4 started from 1 can approach the target inspection site in the reactor pressure vessel 8 without detouring, the traveling distance of the underwater vehicle 4 can be further shortened.

Further, by providing the hinged door 12 for holding the underwater vehicle 4 in the storage container 7, it is possible to prevent the underwater vehicle 4 from jumping out from the storage container 7 even if an unexpected situation occurs. As a result, the underwater vehicle 4 can be reliably stored and held in the storage container 7.

Since the cable 6 can be fed and wound by driving the cable guide mechanism 14 by remote control, it is possible to prevent the cable 6 from interfering with the internal structure of the furnace, and the swimming movement of the underwater vehicle 4 is prevented. The operability can be improved without hindering. Further, even if the underwater vehicle 4 fails, the underwater vehicle 4 can be easily collected in the storage container 7. Then, the cable guide mechanism 14
Since the operation of is checked by the television camera 18 arranged in the vicinity thereof, the cable guide of the underwater vehicle 4 can be performed more reliably. Since the encoder is attached to the drive motor 17 and the feeding distance of the cable 6 can be detected, the moving distance of the underwater vehicle 4 can be known and the operability can be improved. If the drive motor 17 is of an electric type and is housed in a waterproof storage box, the durability of the cable guide mechanism 14 is enhanced and the service life thereof can be extended.

A guidance device 19 for guiding the underwater vehicle 4 and a television camera 22 for monitoring the underwater vehicle 1 are arranged on the side of the storage container 7, and the position of the underwater vehicle 4 is determined by the guidance device 19 and the television camera 22. And cable 6
It becomes easier to check the state of (3), the underwater vehicle 6 can be easily maneuvered, the possibility of collision with an obstacle is reduced, and the approach time to the target inspection site can be shortened. Further, since the angle of the television camera 22 can be remotely changed by the drive motor 23 according to the position of the underwater vehicle 4, the monitoring range of the underwater vehicle 4 can be expanded.

Further, in the reactor internal structure inspection method of this embodiment, after the storage container 7 for storing the underwater vehicle 4 is moved and installed in the vicinity of the target inspection site in the reactor pressure vessel 8, the underwater vehicle 4 is installed. By releasing the hinged door 12 holding the container and starting the underwater vehicle 4 from the opening 11 formed in the bottom of the storage container 7 to perform the inspection, the inspection efficiency can be improved and the inspection time can be shortened. .

FIG. 8 shows an example of visual inspection using a plurality of storage containers 7 according to this embodiment. After each storage container 7 is installed on the upper end of the core shroud 10 by the mast 3 of the refueling machine 2, the traveling wheels 25 turn the upper end of the core shroud 10 to the underwater vehicle start / storage position 43 shown in FIG. When it is moved and reaches the vicinity of the target inspection site, the underwater vehicle 4 is started from the storage container 7 and avoids the core shroud head bolt bracket 9 which is an obstacle, for example, the reactor pressure vessel 8 and the core shroud 10. A visual inspection is performed on the surface of the shroud support plate 52 to which the jet pump 51 is fixed in the annular portion 50 formed in the annular shape in the gap. By visually inspecting using a plurality of storage containers 7 in this way, the visual inspection range can be shared and the visual inspection time can be shortened.

FIG. 9 shows an example of the visual inspection of the underwater vehicle 4 according to this embodiment. The jet pump 51 mounted between the reactor pressure vessel 8 and the core shroud 10 is visually inspected by the underwater vehicle 4. It shows the state. The jet pump 51 is roughly classified into an elbow 53.
The mixing chamber 54, the diffuser 55, the tail pipe 56, and the riser pipe 57.

These parts are connected and fixed to the brackets 58 and 59, the transition piece 60, the riser brace 61 and the shroud support plate 52.
Fixed to or supported by. In addition, in FIG.
2 is a bolt and 63 is an instrumentation tube. In order to confirm the soundness of the jet pump 51 configured as described above, a visual inspection is carried out by the storage container 7 and the underwater vehicle 4 according to the flowchart shown in FIG.

That is, as shown in FIG. 10, first,
The storage container 7 is moved to the vicinity of the jet pump 51, and the holding mechanism drive device 13 for the storage container 7 is driven to move the hinged door 1.
2 is opened and the underwater vehicle 4 is started (steps S1 to S3). The underwater vehicle 4 approaches the jet pump 51 by the automatic control of the control device 5, and the jet pump 51 is inspected in the following order. Inspect the bolt 62, the transition piece 60, and the elbow 53, and check the nozzle 6
4 (shown in FIG. 7) and the welded portion of the riser brace 61,
The mixing chamber 54, the brackets 58 and 59, and the weld between the riser pipe 57 and the recirculation nozzle are inspected (steps S4 to S11).

Next, the instrumentation pipe 63 attached to the jet pump 51, the diffuser 55, and the diffuser 55.
And the tail pipe 56, and the tail pipe 5
6 and the welded portion of the shroud support plate 52 are inspected and the process is finished (steps S12 to S16). When these inspections are completed, the underwater vehicle 4 is floated up, the underwater vehicle 4 is stored and held in the storage container 7, and the entire inspection work is completed.

11 and 12 show an example in which the storage container 7 of this embodiment is installed on the upper lattice plate 70. Figure 11
As shown in, the storage container 7 storing the underwater vehicle 4 is suspended by the mast 3 of the refueling machine 2, the mast 3 is extended, and the storage container 7 is gradually lowered and installed on the upper lattice plate 70. In this case, the storage container 7 is the cylinder 3 of the fixed part 30.
1 is operated to sandwich the upper lattice plate 70 as shown in FIG. Then, the storage container 7 is attached to the upper lattice plate 70.
After the installation, the hinged door 12 in the storage container 7 is opened, the underwater vehicle 4 is started into the core shroud 9, and the visual inspection of the target inspection site is performed. As described above, since the storage container 7 is installed by being sandwiched between the upper lattice plate 70 by the fixing portion 30, the underwater vehicle 4 is stably started from the storage container 7,
Can be stored.

In this embodiment, the mast 3 is used as the moving means for the storage container 7, but the present invention is not limited to this.
An auxiliary hoist of the fuel exchanger 2 or an overhead crane may be used as long as it is moved and installed in the vicinity of the target inspection site.

FIG. 13 is a perspective view of essential parts showing a second embodiment of the nuclear reactor internal structure inspection apparatus according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. In this embodiment, a seating portion 72 is provided in the storage container 7 instead of the fixed portion 30 so that the storage container 7 can be seated on the core shroud head bolt bracket 9.

As described above, according to the present embodiment, since the storage container 7 can be installed in the bracket 9 which hinders the starting and storing of the underwater vehicle 4, the underwater vehicle 4 can be started and stored in a short time. In addition, the cable 6 is prevented from being entangled with or caught by the bracket 9 when the vehicle is started and stored. The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

FIG. 14 is a cross-sectional view of essential parts showing a third embodiment of the nuclear reactor internal structure inspection apparatus according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. In this embodiment, the storage container 80 is composed of a storage box 81 for storing the underwater vehicle 4 and having an opening 82, and a cylindrical guide pole 83 which is coupled to the storage box 81 and guides the cable 6. 80 is suspended by a wire 84 as a moving means.

Therefore, in the present embodiment, the storage container 80 is suspended in the annulus portion 50 of the reactor pressure vessel 8 or placed on the upper lattice plate 70 to start the underwater vehicle 4 from the opening 82. The vehicle is started into the annulus portion 50 or the core shroud 10 and a visual inspection of the target inspection portion is performed. Thus, according to this embodiment, the storage container 8
No drive means, power transmission means, detection means, etc. are provided in the 0, so that the underwater vehicle 4 can be stored easily. The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

[0062]

As described above, according to the invention of claim 1 of the present invention, a container for accommodating an underwater vehicle and having an opening portion through which the underwater vehicle comes in and out, and the accommodating container have an internal reactor structure. Since the moving means for moving and setting the object under inspection to the target inspection site and the holding means for holding the underwater vehicle in the storage container are provided, the traveling distance of the underwater vehicle can be short, and while moving to the target inspection site. The cable is not entangled with or caught in, the possibility of collision with an obstacle is reduced, and the approach time to the narrow space can be shortened. Furthermore, even when the underwater vehicle is collected in the event of a failure, it is sufficient to collect even the storage container, so that it can be easily collected in a short time. Therefore, shortening these times can dramatically improve the operating rate of the plant.

Further, by providing the holding means for holding the underwater vehicle in the storage container, even if an unexpected situation occurs, it is possible to prevent the underwater vehicle from jumping out of the storage container and store the underwater vehicle. It can be reliably stored and held in the container.

According to the second aspect of the present invention, the cable guide mechanism for paying out and winding up the cable of the underwater vehicle is arranged inside the storage container, so that the interference of the cable with the structure can be prevented and the swimming motion of the underwater vehicle. The operability can be improved without hindering the operation.

According to the third aspect of the present invention, the cable guide mechanism has the drive motor, and the encoder for detecting the cable payout distance is attached to the drive motor. Since the travel distance is known, it is easy to control the underwater vehicle.

According to the invention of claim 4, by disposing the television camera for monitoring the underwater vehicle in the storage container, it becomes easy to confirm the position of the underwater vehicle and the state of the cable, and the operation of the underwater vehicle is unfamiliar. It can be easily performed by an operator.

According to the fifth aspect, since the storage container is provided with the traveling means for moving the upper end portion of the core shroud after the core shroud is installed, the storage container can be easily moved to a place where there is no obstacle. As a result, the movement distance of the underwater vehicle is small, and the cable is not entangled or caught while moving to the target inspection site.

According to the present invention, the traveling means is provided with a traveling distance detector for detecting the traveling distance, the traveling distance detection signal is taken into the signal processing device, and the signal of the position preset by the signal processing device is taken. In comparison with the above, by sending the signal processing result to the traveling means as a drive signal, the storage container can be automatically moved to the vicinity of the designated target inspection site, and the storage container can be moved in a short time.

According to the seventh aspect of the present invention, a guide device for guiding the underwater vehicle to the target inspection site is attached to the storage container, thereby avoiding the risk of the underwater vehicle colliding with an obstacle, so that the underwater vehicle can be transferred to the target test site. Therefore, even an operator who is unfamiliar with the operation of the underwater vehicle can easily perform the operation.

According to the eighth aspect of the present invention, since the storage container is provided with the fixing portion for attaching to and detaching from the reactor internal structure, the underwater vehicle is started while the storage container is securely fixed to the reactor internal structure. Can be stored. As a result, the underwater vehicle can be started and stored stably, and the reliability can be improved.

According to the ninth aspect, since the storage container is provided with the seating portion capable of sitting on the obstacle of the target inspection site, the storage container is seated on the obstacle of the target inspection site, and the underwater vehicle is started from there. Then, it is possible to perform visual inspection by approaching the target inspection site. As a result, the cable is not entangled or caught before the underwater vehicle moves to the target inspection site, and the risk of collision with an obstacle can be avoided.

According to the invention of claim 10, after the storage container for storing the underwater vehicle is moved and installed in the vicinity of the target inspection site of the reactor internal structure, the holding means for holding the underwater vehicle is released, and the storage container is released. The inspection efficiency can be improved and the inspection time can be shortened by starting the underwater vehicle from the opening formed in the above and performing the inspection.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an overall configuration of a first embodiment of a nuclear reactor internal structure inspection apparatus according to the present invention.

FIG. 2 is a configuration diagram showing a state in which the storage container shown in FIG. 1 is installed at an upper end portion of a core shroud.

FIG. 3 is an enlarged perspective view of an essential part showing a state in which the storage container shown in FIG. 1 is installed at the upper end of the core shroud.

FIG. 4 is a cross-sectional view showing the internal structure of the storage container shown in FIG.

FIG. 5 is an overall view showing the underwater vehicle of FIG.

FIG. 6 is a configuration diagram showing a control system of the underwater vehicle, the control device, and the storage container in FIG. 2.

[Fig. 7] Underwater vehicle start-up in the reactor pressure vessel
FIG. 3 is a cross-sectional view showing a storage position.

FIG. 8 is a perspective view showing a partially cutaway example of visual inspection using a plurality of storage containers.

FIG. 9 is a perspective view showing a state in which a jet pump is visually inspected with an underwater vehicle.

FIG. 10 is a flowchart showing the sequence of visually inspecting the jet pump.

FIG. 11 is a configuration diagram showing an example in which a storage container is installed on an upper lattice plate.

FIG. 12 is an enlarged plan view of an essential part showing an example in which a storage container is installed on an upper lattice plate.

FIG. 13 is a second view of the reactor internal structure inspection device according to the present invention.
The principal part expansion perspective view which shows an Example.

FIG. 14 is a third view of the reactor internal structure inspection apparatus according to the present invention.
Sectional drawing of the principal part which shows an Example.

[Explanation of symbols]

 1 Operation Floor 2 Fuel Exchanger 3 Mast (Movement) 4 Underwater Vehicle 5 Control Device 6 Cable 7 Storage Container 8 Reactor Pressure Vessel 9 Core Shroud Head Bolt Bracket 10 Core Shroud 11 Opening 12 Hinged Door (Holding Means) 13 Holding Mechanism drive device 14 Cable guide mechanism 17 Drive motor 18 TV camera 19 Guidance device 20 TV camera 21 Lighting equipment 22 TV camera 24 Grasping portion 25 Traveling wheel (traveling means) 26 Power transmission mechanism 27 Drive motor 28 Travel distance detector 30 Fixed part 35 Front-rear propulsion mechanism 36 Vertical propulsion mechanism 37 Balance weight 38 Movable TV camera 39 Lighting device 43 Solenoid valve 46 Water depth detector 50 Annulus part 51 Jet pump 70 Upper lattice plate 72 Seating part

Claims (10)

[Claims] 1. An underwater vehicle is constructed by providing a propulsion mechanism and an attitude control means in a pressure-resistant casing equipped with a visual observation camera and a lighting device, and the underwater vehicle is remotely operated while swimming in water. In a nuclear reactor internal structure inspection device configured to perform a visual inspection of internal structures, a storage container that stores the underwater vehicle and has an opening portion through which the underwater vehicle enters and exits, and the storage container in the reactor. A moving means for moving and installing the structure in the vicinity of the target inspection site of the structure and a holding means for holding the underwater vehicle in the storage container are released at the time of inspection, and the holding means is opened from the opening of the storage container. An in-reactor internal structure inspection device characterized by starting an underwater vehicle. 2. The nuclear reactor internal structure inspection apparatus according to claim 1, wherein a cable guide mechanism for feeding out and winding up the cable of the underwater vehicle is provided inside the storage container. In-reactor structure inspection device. 3. The nuclear reactor internal structure according to claim 2, wherein the cable guide mechanism has a drive motor, and an encoder for detecting a cable feeding distance is attached to the drive motor. Inspection device. 4. The nuclear reactor internal structure inspection apparatus according to claim 1 or 2, wherein a television camera for monitoring the underwater vehicle is arranged in the storage container. apparatus. 5. The nuclear reactor internal structure inspection apparatus according to claim 1, 2, or 4, wherein the storage container is provided with a traveling means for moving an upper end portion thereof after the core shroud is installed. Structure inspection device. 6. The nuclear reactor internal structure inspection apparatus according to claim 5, wherein the traveling means is provided with a traveling distance detector for detecting a traveling distance, and the traveling distance detection signal is taken into a signal processing device, An apparatus for inspecting a structure inside a nuclear reactor, characterized in that the signal processing apparatus compares the signal at a preset position with the signal processing result and sends it to the traveling means as a drive signal. 7. The nuclear reactor internal structure inspection device according to claim 1, 2, 4 or 5, wherein the storage container is provided with a guide device for guiding the underwater vehicle to a target inspection site. In-reactor internal structure inspection device. 8. The reactor internal structure inspection apparatus according to claim 1, 2, 4, 5 or 7, wherein the storage container includes a fixing portion for attaching to and detaching from the reactor internal structure. In-reactor internal structure inspection device. 9. The nuclear reactor internal structure inspection device according to claim 1, 2, 4, 5 or 7, wherein the storage container has a seating portion capable of seating on an obstacle at a target inspection site. In-reactor internal structure inspection device. 10. A visual inspection of internal structures of a nuclear reactor while remotely swimming an underwater vehicle in which a propulsion mechanism and attitude control means are provided in a pressure-resistant casing equipped with a visual observation camera and a lighting device. In the in-reactor internal structure inspection method, the storage container for storing the underwater vehicle is moved and installed in the vicinity of the target inspection site of the in-reactor internal structure, and then holding means for holding the underwater vehicle is provided. A method for inspecting an internal structure of a nuclear reactor, which is released, and an inspection is performed by starting the underwater vehicle from an opening formed in the storage container.