JPH04141324A - Cutting device - Google Patents

Abstract

PURPOSE:To take out only an irradiated material in a pipe, by cutting a pipe fixed on an underwater work bench with underwater electric discharging by the electrode of an electric discharge machine, and storing in a storage container only the irradiated material with its extruding from the pipe with an extrusion mechanism. CONSTITUTION:An electrode 5 connected via a holder 4 to an electric discharge machine 2 is dipped freely movably underwater. A pipe 6 in which a lighting material is stored and which is fixed by a press device 7 on an underwater work bench 13 is cut by the underwater electric discharging of this electrode 5, and only the irradiated material is stored in a storage container 9 with its extruding from the pipe 6 by the extrusion mechanism 8 installed on this work bench 13. Consequently only the irradiated material in the pipe 6 can be stored in an exclusive transfer container.

Description

[Detailed description of the invention]

[Object of the Invention] (Industrial Application Field) The present invention relates to a cutting device, and more particularly to a cutting device that cuts a pipe containing an irradiation material by underwater electric discharge machining and makes it possible to extract only the irradiation material inside. . (Prior Art) In recent years, various new moon charges have come to be used for nuclear reactors. Regarding these new moon charges, it is necessary to fully consider the effects of irradiation by neutrons, etc. for the safety of facilities. For this reason, after these materials are irradiated in a nuclear reactor or the like, they are subjected to various Mi I material tests in a hot laboratory. In addition, in order to conduct the test, it is necessary to obtain a test piece using the following material preparation method. First, the test material is placed in a long pipe made of steel or the like, and this pipe is further set in a nuclear reactor and a predetermined irradiation test is performed. Then, the pipe is taken out from inside the furnace using a safe method, and furthermore, the pipe taken out from inside the furnace is cut to a certain length using a special cutting tool, and the pipe is placed in a special transportation container. This transport container is called a cask, and highly radioactive materials are kept inside the container.

[-By filling, it is possible to prevent radioactivity from leaking out of the container. This transport container is transported from nuclear reactor equipment such as a nuclear power plant to an external hot laboratory where various tests are performed. The above series of operations will be explained in detail with reference to FIGS. 5 to 7. In FIG. 5, reference numeral 21 indicates a nuclear reactor, and this nuclear chip 21 is in a stopped state and the inside of the reactor is being inspected. A core support plate 22 is installed in the lower part of the reactor interior 21, while an upper lattice plate 23 is installed in the upper part. A pipe 24 containing the irradiation material is vertically arranged and installed between the core support plate 22 and the upper grid plate 2B. After the irradiation, this pipe 24 is removed from the core support plate 22 using a special handling tool 25, and is then removed from the reactor core 22.
Auxiliary hoist 2 of fuel exchanger 26 located above 1
The fuel is transferred into the fuel pull 28 while being suspended by the fuel tank 7. This FIG. 6 shows the details of the special handling tool 25,
This special handling tool 25 has a cylindrical manipulator structure,
Two claws are attached to part of the side. This claw 2
9 grips the upper part of the pipe 24 which has been sealed to the upper lattice plate 23, and presses it downward.
fulfills the role of "removal" from Further, the special handling tool 25 can be remotely controlled by air supplied through an air hose 30. The upper part of the vibrator 24 has a retractable structure with a built-in spring, and can be easily contracted downward with the claw 29 of the handling tool 25. Furthermore, as shown in FIG. 7, within the spent fuel pool 28,
A pipe cutting and folding device 32 is supported by a lifting jig 31 suspended by a crane (not shown). Further, this pipe cutting device 32 is equipped with a push cutter 33 and is configured to cut the pipe 24 held by the holder 34 together with the irradiated material inside the pipe 24. The pipe cutting device 32 is operated remotely using high pressure water supplied by a hydraulic hose 35. Further I;I
The cut pipe 24 is stored in a special transportation container (not shown) by the cut piece gripping device 36, and is transported from nuclear reactor equipment such as the Kuko Power Plant to an external hot laboratory. (Problem to be solved by the invention) However, such a method has the following drawbacks. In other words, even though the hot lab requires only the irradiated material inside the pipes, the pipes that have become highly radioactive inside the reactor are also transported at the same time. Therefore, there is a problem in that this pipe must be disposed of as radioactive waste after the irradiated material is removed. In addition, if a special IuJI analyzer is used to cut the pipe with the irradiated material still contained in it, the cut surface of the pipe will deform unevenly, making it difficult to remove the irradiated material from inside the pipe. There is a problem in that if it is forcibly removed, the irradiated material will be damaged and the test will be adversely affected. SUMMARY OF THE INVENTION Therefore, the purpose of the present invention is to solve the above-mentioned problems with the conventional technology and to provide a pipe and a irradiation material so that only the irradiated material necessary for the test can be taken out in a state that is effective for the test. An object of the present invention is to provide a cutting device capable of cutting. [Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention movably immerses an electrode connected to an electrical discharge machine through a holder in water, and A pipe containing irradiation material fixed on an underwater workbench is cut by underwater electric discharge machining, and only the irradiation material is extruded from the pipe by an extrusion mechanism installed on the workbench and stored in a storage container. It is characterized by the following. (Function) According to the present invention, an electrode connected to an electric discharge machine via a holder is movably immersed in water, and the inside fixed on an underwater workbench is irradiated by underwater electric discharge machining of the electrode. The pipe containing the material was cut, and only the irradiated material was extruded from the pipe using the extrusion mechanism installed on the workbench and stored in the storage container, so only the illumination material inside the pipe could be transported exclusively. It can be stored in a container, and when cutting the pipe, it does not deform the pipe into a flat shape, and the cut surface can be finished smoothly so that it does not crack, making it easy to remove the irradiation material from inside the cut pipe. It can be taken out. (Embodiment) Hereinafter, an embodiment of the cutting device according to the present invention will be described with reference to FIGS. 1 and 2. The cutting device 1 according to the present invention is operated on an operating floor (in air).
Electrical discharge machine 2 installed in and spent fuel storage pull '3
A holder 4 in the shape of a long thin rod with 'fA7M inside, an electrode 5 attached to the tip of the holder 4, a vibro containing the irradiation material, and a gripping part 7a for holding and fixing the vibro horizontally. It is composed of a pipe holding device 7 having a pipe holding device 7, an irradiation material extrusion device 8 that pushes out the irradiation material in the vibro into an irradiation material storage container 9, and an irradiation material storage container 9 placed on the vibrator holding device 7. There is. Further, the pipe holding device 7 is equipped with a first cylinder 10, a second cylinder 11, and a third cylinder 12, which are supplied from a pressure source (not shown) through an air hose. The extrusion operations of the leg gripping portion 7a and the rod 8a of the irradiation + extrusion device 8 can be controlled remotely. Note that the pipe holding device 7 is connected to the spent fuel storage pool 3.
It is placed and fixed on a workbench installed on the wall of
Each device has a waterproof structure that allows reliable operation even underwater. Further, as shown in FIG. 2, the electric discharge machine 2 is installed on a base 14 located at the edge of the spent fuel storage pool 3, and the boulder 4 is freely moved in three axial directions by a motor mechanism (not shown). It is composed of a movable position setting device 15, a power source 16 that supplies electric discharge machining power to the electrode 5, and a servo unit 17 for vertically moving the electrode 5. A holder is attached to the tip of the servo unit 17. 4. The electrode 5 is suspended. Next, the operation of cutting a pipe using the cutting device of the present invention having the following two configurations will be explained with reference to FIGS. 1 to 4. The tape 6 pressed to a certain length is set on the pipe holding device 7 using a general-purpose gripping tool (not shown), and the first cylinder 10 and the second cylinder 11 are operated to hold the vibro in the gripping part 7a. Grip and fix to prevent the pipe from moving during cutting. Further, the above-mentioned cylinder operation can be remotely controlled by a pressurizing source (not shown) via an air hose. In this state, the electrode 5 of the electric discharge machine 2 is brought close to the vibro, and discharge pressure is started. Here, the state of electrical discharge machining will be explained with reference to FIG. An electrode (not shown) is connected to the vibro facing the electrode 5, and as the electrode 5 approaches the vibro, discharge is started. As a result, the two-legged vibro's thickness decreases,
Further, the discharge is continued and the vibro is cut off. At this time,
The bipedal electrode 5 repeats minute vertical movements and then is sent downward, and this movement is controlled by a servo unit 17. In addition, the above discharge is performed in a pulsed manner under the control of the power source 16 in accordance with the vertical movement of the electrode.
It can be done. After cutting, the movement of the electrode 5 is automatically stopped under the control of the ZARHO unit 17. Position setting device after stopping] 5
Pull up the electrode 5 more. When the machining of one end face is completed, the position setting device of the electrical discharge machine 2 is used to move the other end face 21
- Perform positioning of the nodame electrode 5. After positioning, electric discharge machining is started in the same manner as described above. Next, the irradiated material in the vibro, which has been processed on both ends, is placed in the fourth
As shown in the figure, by operating the third cylinder 12, the irradiated food is pushed out by the push rod 20 provided in the irradiation cooking device No. 2, and transferred and stored in the irradiation material storage container 9. Thereafter, this irradiation material storage container 9 is capped, placed in a dedicated transport container, and transported to an external hot lab. On the other hand, the pipe that does not contain irradiated material is the reactor equipment (i)
It is designed to be disposed of at designated waste disposal sites. Furthermore, since the discharge cutting of the pipe is performed while the pipe is immersed in the fuel storage pool, the worker is not exposed to the effects of radiation during this work. At this time, by further performing electric discharge machining on the end surface of the pipe whose end surface has been deformed into a flat shape while accommodating the irradiation ashes, it is possible to cut the pipe together with the irradiation material while maintaining a perfect circle. Sara? In this way, the end face of the vibrator after cutting 1υ1 can be finished with a clean surface without any stiffness, and it becomes possible to take out the irradiation material inside the pipe to each station. As mentioned above, highly activated pipes and irradiation inside the pipes +
4 can be separated prior to the test, it is possible to prevent highly activated pipes from being carelessly taken out of the nuclear reactor facility 6ii as waste. [Effects of the Invention] As is clear from the following two inventions, the cutting device of the present invention cuts a pipe fixed on an underwater workbench by underwater electrical discharge machining using the electrode of an electrical discharge machine, and the extrusion mechanism By extruding only the irradiated material from the pipe and storing it in the container, it is possible to take out only the irradiated material inside the pipe, and the highly activated barb can be taken out of the reactor equipment. This has the effect of eliminating the need to take it out. 】】

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a cutting device according to the present invention, FIG. 2 is a side view showing an embodiment of an electric discharge machine used in the cutting device according to the present invention, and FIG. ), (
b) is a front view showing how the pipe is cut by electric discharge machining, Fig. 4 is a partial vertical sectional view showing how the irradiated material is handled after cutting, and Fig. 5 is the installation of a pipe containing the conventional irradiated material. FIG. 6 is an enlarged view of the same portion, and FIG. 7 is a schematic overall view showing the state of cutting of a pipe containing a conventional irradiation material. DESCRIPTION OF SYMBOLS 1... Cutting device, 2... Electric discharge machine, 3... Spent fuel storage pool, 4... Holder, 5... Electrode, 6
. . . Pipe, 7. Pipe holding device, 8. irradiation material extrusion device, 9. irradiation material storage container. Applicant's agent Mr. Sato

Claims (1)

[Claims] An electrode connected to an electrical discharge machine via a holder is movably immersed in water, and a pipe fixed on an underwater workbench containing an irradiation material is cut by underwater electrical discharge machining of the electrode. A cutting device characterized in that the extrusion mechanism installed on the workbench extrudes only the irradiation material from the pipe and stores it in a storage container.