JP2735185B2 - Reactor pressure vessel inspection equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a reactor pressure vessel (hereinafter, referred to as a boiling water reactor).
The present invention relates to a reactor pressure vessel inspection device for inspecting a reactor pressure vessel (RPV), and more particularly to a reactor pressure vessel inspection device for inspecting an upper end surface (hereinafter, referred to as a “flange surface”) of an RPV. (Prior art) For example, in a BWR plant, various inspections have been automated for the purpose of reducing the radiation exposure of workers and improving the operation rate of the plant.
Inspection of the flange surface is generally performed by a worker directly. The specific contents are as follows. Cleaning work with jet water after draining water from RPV. Work to remove rags from the RPV seal surface. Visual inspection of RPV seal surface. Polishing of flange surface with sandpaper. Among these various operations, the operations are performed a plurality of times in relation to other operation processes. If there is a flaw as a result of the inspection, repair work is performed. Here, the repairing operation is a polishing operation using sandpaper in the same manner as described above. The above configuration has the following problems. First of all, heavy equipment is required to perform complicated work, which places a heavy burden on workers, and workers near the RPV are exposed to high radiation. In addition, since the operation requires a long time, the operation rate of the plant is reduced. In addition, the upper opening of the RPV is open at the time of work, so that there is a risk of falling of various working tools as well as of workers. (Problems to be solved by the invention) As described above, in the past, most of the inspection work on the RPV flange surface was performed directly by the workers, so that the workers were exposed to radiation and the plant was operated. The present invention has been made based on such a point, and the purpose of the present invention is to make the inspection operation of the reactor pressure vessel an automatic operation by remote control. Accordingly, it is an object of the present invention to provide a reactor pressure vessel inspection device capable of solving the various problems described above. [Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, a reactor pressure vessel inspection device of the present invention is provided on a top surface of a reactor pressure vessel on a platform for a refueling machine. An inspection device main body having an imaging device that is suspended via a wire rope disposed along a mast and a hook of a refueling machine installed so as to be able to travel and that captures an upper end surface of the reactor pressure vessel, A support provided on the apparatus main body and having a roller support inside the reactor pressure vessel, a guide roller rotatably held by the roller support, and a guide roller provided on the inspection apparatus main body, wherein the guide roller is provided on the reactor pressure vessel. And a plurality of wheels for moving the inspection apparatus main body suspended from the upper end surface of the reactor pressure vessel so as to contact the inner wall surface of the reactor pressure vessel toward the outside of the reactor pressure vessel. Here, it is particularly preferable that the inspection device main body includes a cleaning / repair device for cleaning and repairing the upper end surface of the reactor pressure vessel. (Operation) In the reactor pressure vessel inspection apparatus of the present invention, the inspection apparatus main body is arranged from above the reactor pressure vessel along a mast and a hook of a refueling machine movably installed on a refueling platform. It is hung via the arranged wire rope and placed on the container flange surface. The main body of the inspection device can travel on the flange surface of the container in the circumferential direction by the traveling device. While running, the flange surface is cleaned and repaired by the cleaning / repair device, and the image information is remotely captured by imaging the flange surface by the imaging device. Transmit to the operation unit. (Embodiment) An embodiment of the present invention will be described below with reference to FIG. 1 to FIG. FIG. 1 is a sectional view showing a state in which a reactor pressure vessel inspection apparatus according to the present embodiment is applied to a BWR, and reference numeral 1 in the figure denotes a reactor building. In this reactor building 1, RPV2
Is installed on the pedestal 3. A heat shield wall 4 is provided on the outer periphery of the RPV 2. At the upper end of the reactor building 1, a platform 5 for a refueling machine is installed, and on this platform 5, a refueling machine 6 is movably arranged. The RPV 2 has a lid (not shown) removed and an upper opening thereof opened, and a plurality of stud bolts 8 for fixing the lid are attached to an upper flange surface 7 thereof. On the flange surface 7, the reactor pressure vessel inspection device 11 according to the present embodiment is mounted. The reactor pressure vessel inspection device 11 is suspended via a wire rope 12 disposed along the mast 13 and the hook 14 of the refueling machine 6, thereby preventing the reactor pressure vessel from falling into the RPV 2. I have. The wire rope 12 is a lifting mechanism 6a installed on the refueling machine 6.
It is wound around. Next, the configuration of the reactor pressure vessel inspection device 11 will be described in detail with reference to FIGS. In the figure, reference numeral 15 denotes an inspection device main body, which runs in a circumferential direction by a traveling device 16 on a sealing portion (a portion where a sealing ring comes into contact when the lid is closed) of the flange surface 7. I do.
That is, a traveling drive mechanism 16a is provided at one end (right side in the figure) of the inspection device main body 15, and a pair of wheels 17a and 17b are fixed to the traveling drive mechanism 16a. Inspection device body 15
Another pair of wheels 18a and 18b are attached to the other end of the wheel. Therefore, when the traveling drive mechanism 16a is driven, the flange surface 7 is driven through the four wheels 17a, 17b, 18a, and 18b.
Drive on. The drive mechanism 16a is controlled by the control mechanism 19 and can travel in any direction, and the switching is performed by the control mechanism 19. A guide roller 20 is attached to a side portion of the main body 15 on the inner peripheral surface side of the RPV 2 via a support 21. The steering angles of the wheels 17a, 17b, 18a, 18b are set slightly larger than the circumference of the RPV 2. Therefore inspection device 11
Tends to run radially outward, whereby the guide roller 20 is constantly pressed against the inner peripheral surface of the RPV 2, so that the inspection device 11 travels in a stable state without coming off the flange surface 7. The wheels 17a, 17b,
The materials of the 18a, 18b and the guide roller 20 are selected so as not to damage the RPV 2 (generally made of austenitic stainless steel), and are made of, for example, hard rubber or plastic. A cleaning / repair device 22 is attached to the inspection device main body 15. The cleaning / repair device 22 includes a polishing mechanism 23, a driving mechanism 24 for rotating the polishing mechanism 23, and a driving mechanism
And a belt 25 for transmitting rotation to the polishing mechanism 23. The polishing mechanism 23 includes a sandpaper 23a in a cylinder 2
3b, which is for polishing the flange surface 7 when rotated by the drive mechanism 24. In addition, instead of the polishing mechanism 23, a mechanism provided with a cleaning cloth may be attached. The rotation direction of the polishing mechanism 23 is opposite to the traveling direction of the inspection device main body 15. This enables effective polishing. An imaging device 26 is attached to the inspection device main body 15. The imaging device 26 includes a TV camera 27, a lighting device 28, a transmission mechanism 29, and a cable 30 for transmitting an upper portion from the transmission mechanism 29 to a control unit disposed remotely.
This cable 30 is also provided along the mast 13. The flange surface 7 is illuminated by the lighting device 28, and the TV camera 27 captures an image of the flange surface 7 in that state. The captured image information is transmitted from the transmission mechanism 29 to the remote operation unit via the cable 30. At that time, depending on the location of the wound or foreign matter, it may not be possible to directly image it with the TV camera 27.
A method of taking an image with the camera 27 is adopted. This is the third
This will be described with reference to the drawings. Fig. 3 shows TV camera 27 and lighting equipment 28
FIG. 3 is a diagram showing a positional relationship between the object and the foreign matter 31 or the scratch 32;
TV camera 27 and lighting fixture 28 as shown in FIGS.
If the optical axis of
It is difficult to capture 32 shadows. The third
As shown in FIGS. 9C and 9D, the optical axis of the TV color 27 is shifted from that of the lighting fixture 28, and the shadow of the foreign matter 31 or the scratch 32 is obtained (the hatched portion in the figures is imaged as a shadow). Can be imaged. In this embodiment, paying attention to such a point, as shown in FIG. 2, the TV camera 27 and the lighting fixture 28 are mounted with their optical axes shifted from each other. The operation will be described based on the above configuration. First inspection equipment
11 runs on the flange surface 7, and the refueling machine 6 moves accordingly. Since the refueling machine 6 can move in two orthogonal directions, it can follow the movement of the inspection device 11 sufficiently. When the inspection device 11 travels, the condition of the flange surface 7 is imaged by the TV camera 27 and transmitted to the transmission mechanism.
The data is transmitted to the remote control unit via the cable 29 and the cable 30. Thereby, the condition of the flange surface 7 can be remotely confirmed. At the same time, the polishing mechanism 23 is rotated in a direction opposite to the running direction of the inspection device 11 , and at this time, the flange surface 7 is polished by the sandpaper 23a, thereby performing repair. Even if the inspection device 11 comes off the flange surface 7 during traveling, the inspection device 11 is supported by the fuel exchanger 6 via the wire rope 12, so that it can be easily collected without falling into the RPV 2. According to the present embodiment, the following effects can be obtained. First, inspection work and repair work on the flange surface 7 of the RPV 2 can be performed automatically and by remote control. Therefore, radiation exposure of the worker can be significantly reduced, and the burden on the worker can be reduced. In addition, since the operation time is greatly reduced, the operation rate of the plant can be improved. Further, since the worker does not work directly near the flange surface 7, the worker does not fall into the RPV 2, and the inspection device 11 is also supported by the refueling machine 6 via the wire rope 12. As a result, falling into the RPV 2 is also reliably prevented. Even if the flanges 7 come off from the flange surface 7, they can be easily recovered by the fuel exchanger 6 via the wire rope 12. In addition, a guide roller 20 is attached to the inspection device main body 15 via a support 21 so as to guide the traveling of the inspection device 11 , and the steering angles of the wheels 17a, 17b, 18a, and 18b are set to the circumference of the RPV2. Since it is set slightly larger than
The guide roller 20 is constantly pressed against the inner peripheral surface of the RPV 2. Therefore, the traveling of the inspection device 11 can be stabilized, and the falling thereof can be reliably prevented. Also, even in the case where the wire rope 12 comes off, since the wire rope 12 is supported by the wire rope 12 as described above, the fall is reliably prevented. In addition, since the TV camera 27 and the lighting fixture 28 are arranged so as to be able to image the shadow of the foreign matter 31 or the scratch 32, not only the TV camera 27 can directly image the foreign matter 31 or the scratch 32 but also if the direct image cannot be taken. Therefore, the shadow can be imaged, and a highly reliable inspection can be performed. Note that the present invention is not limited to the one embodiment,
For example, the symmetrical container is not limited to the BWR RPV, but can be applied to various containers. Further, in the above-described embodiment, the positional relationship of various devices with respect to the traveling direction has not been particularly described (in the above-described embodiment, it is described that the vehicle can travel in any direction). When performing cleaning by attaching a cleaning cloth (provided with a cleaning cloth), it is conceivable to arrange a cleaning mechanism in front of the traveling direction and an imaging mechanism behind the cleaning mechanism. Thereby, it is possible to image the flange surface after cleaning. When the vehicle can travel in any direction, it is not necessary to consider the above positional relationship. Further, a system that automatically determines the presence or absence of a flaw or the like based on the obtained image information is also conceivable. [Effects of the Invention] As described above, according to the reactor pressure vessel inspection device of the present invention, the flange surface inspection work that has been entrusted to the direct work of the operator can be performed automatically and remotely. Therefore, the burden on the operator can be significantly reduced, and the operation rate of the plant can be improved. Further, the inspection device body is suspended by a wire rope, that is, the inspection device body is mounted on the upper end surface of the reactor pressure vessel along the mast and hooks of the refueling machine movably mounted on the refueling platform. Because it is suspended via wire ropes installed in the reactor pressure vessel, it is possible to prevent the inspection device main body from falling into the reactor pressure vessel from the upper end surface of the reactor pressure vessel while ensuring that The upper end surface can be inspected over the entire circumference of the reactor pressure vessel.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 3 show an embodiment of the present invention.
The figure is a cross-sectional view showing the state where the inspection device is applied to the BWR.
FIG. 3 is a perspective view of the inspection apparatus, and FIGS. 3A to 3D are views showing a positional relationship between a TV camera and a lighting device. 2 RPV, 6 Refueling machine, 7 Flange surface, 11
…… Reactor pressure vessel inspection equipment, 12 …… Wire rope,
15… Inspection device body, 16… Driving drive mechanism, 17a, 17b,
18a, 18b: Wheel, 19: Control mechanism, 22: Cleaning mechanism, 2
6 ... Imaging mechanism.

Claims (1)

(57) [Claims] At the upper end surface of the reactor pressure vessel, it is suspended via a wire rope arranged along a mast and a hook of the refueling machine installed so as to be able to run on a platform for the refueling machine, and An inspection device main body having an imaging device for imaging an upper end surface, a support tool provided on the inspection device main body and having a roller support portion inside the reactor pressure vessel, and rotatably held by the roller support portion A guide roller, the inspection device main body provided on the inspection device main body, and the inspection device main body suspended from an upper end surface of the reactor pressure vessel so that the guide roller contacts an inner wall surface of the reactor pressure vessel. A reactor pressure vessel inspection device, comprising: a plurality of wheels traveling toward the outside of the pressure vessel. 2. 2. The reactor pressure vessel inspection apparatus according to claim 1, wherein the inspection apparatus main body includes a cleaning / repair device that cleans and repairs an upper end surface of the reactor pressure vessel.