JPS6030635B2 - Cask vertical suspension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a device that facilitates the operation of attaching and detaching a hanging device to be lifted or suspended from a container containing spent nuclear fuel (hereinafter referred to as a cask) underwater, and also displays the attachment and detachment. Regarding.

Among light water reactors, both boiling water reactors (BWRs) and pressurized water reactors (PWRs) are shut down and their fuel replaced once a year. Every year, 1/4 of the fuel rods in the core in BWR and 1'3 in PWR are replaced. One example of this fuel rod is U-235, which has a diameter of 1.25 meters, a length of the exothermic part of 366 meters, and a length of 366 meters. It is housed inside the cladding tube of A-2 and consists of an assembly of several dozen fuel rods, and it is a highly radioactive object, so it must be handled with care. . When inspecting the reactor, the reactor cavity is filled with water, the fuel rods are extracted from the water by a fuel handling machine, and then pulled into the nuclear fuel storage pool through the fuel transportation groove provided in the partition between the fuel pool and the nuclear fuel storage pool. Store it temporarily in a rack in the pool.

After the spent fuel is cooled for a predetermined period of time, it is loaded into a spent fuel transport container (cask) placed in a predetermined location within the pool. The cask is a heavy cylindrical object with a height of about 6 skins and radiating fins of about 2 inches in diameter, and weighs about 100 tons.

For this reason, be careful when lifting and lowering the cask vertically.
Avoid damaging the pool side walls or cask fins. On the other hand, when hoisting a cask, it is important to ensure accurate and reliable iron engagement between the cask's post (trunnion) located at the bottom of the pool, which has a depth of about 12 mm, and the arm of the hanging body. This is what is requested. However, since the iron fitting between the arm for hanging the cask and the trunnion installed on the cask is done about 6 skins below the water surface, it is difficult to visually check it properly due to the refraction of light, and there are small waves on the water surface. The reflection from standing still makes the task even more difficult. In addition, it is dark underwater, so underwater floodlights are used, but this does not alleviate the difficulty of visual confirmation and work, which takes time. Therefore, even if you use a mirror, underwater camera, underwater television, etc. as an auxiliary viewing device, it will be difficult to confirm the relative position between the cask and the hanging equipment.
There is also the problem that the part to be checked cannot be sufficiently monitored because it is obstructed by the protruding members of the hanger. In addition, since the cask is used to store fuel, it is strongly required to ensure the attachment and detachment of this hanging odor in order to shorten the working time and to ensure work safety. The present invention is intended to solve such problems, and aims to propose a cask vertical hanging device that allows reliable and easy confirmation of attachment and detachment of a hanging tool and a cask.

In short, this invention is for vertically suspending a cask located underwater, and involves setting and checking the relative position and centering of the vertical relationship between the cask and the lifting device body, and the direction of the cask station. The vertical cask is designed so that it is possible to check the correct horizontal alignment with the scutrunnion, the proper load on the trunnion, and the confirmation by installing it near each confirmation position on the lifting device or by using a display board attached to the arm of the link device. It is characterized by being a hanging device.

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

Reference numeral 1 denotes a main body of the hanging device, and the cask is lifted or suspended by a hook 22 via a pin 21. An arm 2 for hanging the cask is attached to the hanging odor main body 1 so as to be rotatable around a shaft 3. A rotating plate 4 is connected to the arm, and this rotating plate is connected to a driving device 5 which is a cylinder operated by hydraulic pressure or pneumatic pressure.

6a, 6b and 8a, 8b are guide plates connected with bolts or the like to plate-shaped protrusions 101, 102 extending from the odor hanging body. The guide plates 6a, 6b, 8a, 8b have long holes 80.
a is provided so that the hanging length from the plate-shaped protrusions 101 and 102 can be freely adjusted. FIG. 3 is a detailed view (partially in section) of section A in FIG. 2, showing a link mechanism that displays the vertical relative position between the hanging tool 1 and the upper surface of the cask.

The weight IQ is connected to the rod 11, and its upper end is connected to the display plate 13.
The V-shaped arm 12 is connected to the arm 12 via a pin 2b that can slide within the slit 12a of the V-shaped arm 12. When the bottom surface of the weight 10 comes into contact with the top surface of the cask, the V-shaped arm 12 is activated. When the bottom surface of the guide boss 81a and the top surface of the weight come into contact (position 10' in the figure), the display board 13 should be horizontal with the top surface facing up. Adjust the guide plate 8a so that the center of the hole 2a to fit into it is exactly aligned with the axis ○ of the trunnion 25.
The height direction position of the guide plate can be adjusted by tightening and fixing with a vertical nut 80b using the elongated hole 80a of the guide plate. The circumferential relative position and alignment of the hanging odor main body and the cask 9 can be determined by guide plates 6a, 6b and guide pins 23a, 23b.

Holes 60a, 60b corresponding to the outer diameters of the guide pins 23a, 23b are provided at the bottoms of the guide plates 6a, 6b. The tops of the guide pins 23a, 23b are formed into a substantially conical shape,
At its top, a guide string 24a is inserted through holes 60a and 60b.
, 240 are connected, and using this guide string as a guide, the guide pins 23a and 23b are easily engaged with the holes 60a and 60b, respectively, by using the conical part at the top, and the central direction position and the center of the cask and the sling main body are adjusted. can be matched. As a result, the vertical relative position of the suspension main body with respect to the previous cask is determined, and the relative position centering in all directions is performed, and the center of the hole 2a and the center of the trunnion 25 can be aligned when the arm 2 is operated. . When the drive device 5 is then actuated, the arm 2 moves from 2' to the position 2 in FIG.
It is located nearer to the cask than 5a, hanging down almost vertically.

As a result, the display board 17 with the weight 15 is rotated from the 17' position to the illustrated position 17, making the top surface of the display board 17 horizontal, making it easy for workers to see from outside the pool water surface, and the arm is in the normal position. You will be confirmed that you have arrived in person. Next, when lifting and moving the hanging odor body upward by a small dimension, use the fifth
6, the contact piece 28 of the link mechanism 26 connected to the arm 2 comes into contact with the lower surface 25b of the trunnion 25, and as shown in FIG. Displaced to 27 positions with its top surface horizontal,
It is displayed that a load is applied to the hanging odor main body 1.

The link mechanism 26 consists of links 26a, 26b, and 26c, and the display board 27 is attached by the links 26c. Further, the length of the link 26b can be adjusted so that the display board 27 can be placed in an appropriate display position. The above is the hanging tool body 1
The case of lifting the cask 9 has been described above, but when removing the hanging tool, the display board will be activated by using the bottle in the opposite manner to that described above, and the display board will return to the position where the hanging odor release display is displayed.

In addition, as shown in Fig. 7, a light emitting means (lamp, etc.) 2 is mounted on the display board.
When 0 is provided, the display in dark water becomes even clearer. By carrying out this invention, it becomes easy to attach and detach the arm 2 of the hanging odor main body 1 and the trunnion 25 of the cask 9, and the attaching and detaching process can be sequentially displayed in red, yellow, and blue by distinguishing the colors of the display board. Once all three types of display boards are in place, safe lifting can be carried out, making it easier and safer to lift and lower casks with high levels of radioactivity, reducing work time and ensuring safety. This has the effect of allowing easy handling.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a cask vertical suspension device according to the present invention, Fig. 2 is a front view of the device of Fig. 1, Fig. 3 is a detailed view of section A in Fig. 2, and Fig. 4 is a perspective view of the cask vertical suspension device according to the present invention. 2 is a detailed view of part B, FIG. 5 is a CC view of FIG. 4, FIG. 6 is a sectional view taken along line D-D of FIG. 5,
FIG. 7 is a cross-sectional view of a display board in which a light emitting body is provided with lamps and the like. 1... Hanging tool body, 2... Arm also 5
... Drive device, 6a, 6b, 8a, 8b...
...Information board, 9.... ...Cask, 10...
Gun weight, 13, turtle 7, 27...Display board, 23a? 2
3b...Guide pin, 25... ... Trunnion, 25a... Ear part 26... Link mechanism.

Claims (1)

[Claims] 1. In a device that vertically suspends a cask located in water, setting and confirmation of the relative position and centering of the vertical relationship between the cask and the lifting device main body and the circumferential direction of the cask, and the setting and checking of the relative position and centering of the cask and the lifting device main body, and the A cask characterized in that it is formed so that the fitting and confirmation of the cask trunnion and the load on the trunnion can be confirmed by means of a display plate attached to an arm of a link device provided near each confirmation position of a hanging device. Vertical hanging device. 2. The relative position and centering of the cask and the hanging device in the circumferential direction are determined by a plurality of guide pins having a substantially conical shape at the upper part attached to the cask and a guide plate provided on the side of the hanging device body. A cask vertical suspension device according to claim 1. 3. The cask vertical suspension device according to claim 1, wherein the link mechanism is operated by the force of a weight. 4 The fitting operation between the arm of the suspension main body and the cask trunnion is operated by a drive device such as a pneumatic or hydraulic cylinder, and the fitting is confirmed by contact between the display board mounting member attached to the arm and the trunnion. A cask vertical suspension device according to claim 1, characterized in that it is a link mechanism. 5. The cask vertical suspension device according to any one of claims 1 to 4, characterized in that the display board is colored differently for each operating part. 6. The cask vertical suspension device according to any one of claims 1 to 4, characterized in that the display plate is a color-coded light emitting body for identifying operating parts. 7. The cask vertical hanging device according to claim 2, characterized in that the circumferential relative position of the cask and the hanging tool body and the guide plate for centering are adjustable in the vertical direction. 8. A weight is attached to the operating rod that operates the display board for confirming the vertical position of the cask and the sling body, and a guide plate serving as a guide for this operating rod is provided so that the position can be adjusted up and down. A cask vertical suspension device according to claim 1. 9. The cask vertical suspension device according to claim 1, characterized in that a link mechanism attached to the arm displays a load confirmation display on the trunnion.