JP4644181B2 - Reactor structure cutting equipment - Google Patents

Description

  The present invention relates to a reactor facility cutting facility for temporarily placing an in-reactor structure of a nuclear reactor, such as a shroud, in a pool water and cutting it in water.

  In recent years, equipment replacement due to deterioration over time has occurred in nuclear power plants. Among them, the shroud, which is a reactor internal structure, has been replaced by several plants, and various inventions relating to the replacement work have been proposed (see, for example, Patent Document 1).

  In such replacement work, it is necessary to remove other in-core structures due to the structure of the nuclear reactor. The removed in-furnace structure must be disposed of. Since these are highly radioactive, a method of storing them in a waste storage container is generally used. For this purpose, it is necessary to cut them into sizes that can be stored in the waste storage containers. This cutting operation is performed in water, which is an excellent radiation shield, in order to suppress an increase in radiation dose in the work area because the cutting object is highly radioactive.

  In a nuclear power plant or the like, a pool for temporary placement of equipment for temporarily placing high radioactive equipment is installed adjacent to the nuclear reactor. For this reason, the cutting work is generally carried out by transferring the object to be cut from the reactor to a temporary equipment pool where it is cut into a size that can be stored in a waste storage container.

  During this cutting operation, cutting powder and abrasives (grids) used during cutting are secondarily generated when the furnace internal structure is cut. Since these substances are also highly radioactive substances, they must be collected. For those having a relatively small particle size, a method using a filter and a grid collection tank is generally used. When collecting, the filter is moved and used as necessary, or when it becomes full, it needs to be replaced.

Here, although the layout of the temporary storage pool varies depending on the plant, the filter and tank can be used while moving the filter and tank (including replacement work) when a crane that is permanently installed in the building can be used. The tank can be moved. In this way, there is no problem if the filter and tank can be moved and arranged so as not to hinder the cutting work, but depending on the layout of the temporary storage pool, the building permanent overhead crane used for cutting work and the movement of the filter and tank can be used. There are cases where the trajectories of the lifting equipment used intersect. In this case, since the filter and the tank cannot be moved while continuing the cutting operation, it is necessary to interrupt the cutting operation, and there is a disadvantage that the work process becomes long.
JP 2001-21689 A

  As described above, in order to move (replace) the recovery tank, the cutting operation must be interrupted, which makes the operation process longer. And the operation resumption time of a power plant is delayed with the prolonged work process. In addition, there is a problem that the total amount of exposure increases for workers.

  The objective of this invention is providing the cutting equipment of the nuclear reactor structure which can shorten a working process, without accompanying interruption of cutting operation.

Cutting system for a reactor structure according to the present invention is installed in the core outer side, the water is contained water therein temporarily placed the object to be cut, line cutting operation with respect to the cuttings in the water A pool in which a region close to the core shell is a cutting work region, a region far from the core shell is defined as a temporary storage region, a rail installed on an upper surface edge of the pool, and the pool from the core shell An overhead crane for moving the workpiece to the temporary placement area;
A cutting carriage having a gate-shaped support frame that is movably installed on the rail and suspends a cutting head capable of cutting the workpiece, and on the rail, at a position between the core shell and the cutting carriage. is installed, the having a gate-shaped support cradle for Tsu支a retrieval device that is placed near the holding Gu及 beauty the cutting unit for recovering secondary occurring substances with the cutting operation to hold the cut portion of the object to be cut (1) a lifting machine, a temporary support support frame provided in the temporary storage area of the pool , a shield installed on the upper surface of the temporary storage area of the pool , a side surface of the shield or the temporary storage base on the inner wall surface of the support cradle or the pool is fixed, the cutting carriage and the first crane comprises a second crane having an arm pivotally mounted on the base, having a pre-Symbol gantry support cradle Do not disturb the trajectory of Characterized in that made it possible to move the collection tank.

  In the present invention, the second hoisting machine is a jib crane comprising a lifting arm and a base part that holds one end of the arm, and the base part is an upper surface of a temporary placement area adjacent to the cutting work area of the pool. It was fixed to a shield that shields.

  Moreover, in this invention, you may attach and fix the base part of the jib crane which is a 2nd lifting machine to the support stand for temporary placement provided in the temporary placement area | region adjacent to the cutting work area | region of the said pool.

  Moreover, in this invention, you may attach and fix the base part of the jib crane which is a 2nd lifting machine to the support member of the rail for cutting carts installed in the edge upper surface of the said pool.

  Moreover, in this invention, you may attach and fix the base part of the jib crane which is a 2nd lifting machine to the inner wall face of the said pool.

  Furthermore, in this invention, you may erect and fix the base part of the jib crane which is a 2nd lifting machine on the edge floor surface of the said pool.

  According to the present invention, it is possible to move the filter and the grid collection tank without interrupting the cutting operation of the in-furnace structure, so that the cutting operation time can be shortened. In addition, since this work is a work in a high radiation area, the work time is shortened, so it can be expected that the exposure of workers will be reduced. Furthermore, the shortening of the overall construction period can contribute to the early resumption of plant operation.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a reactor structure cutting facility according to the present invention will be described in detail with reference to the drawings.

  1 and 2. FIG. 3 shows a nuclear reactor of a general nuclear power generation facility and related facilities. FIG. 1 is a perspective view, FIG. 2 is a plan view, and FIG. 3 is a front view.

  In these drawings, reference numeral 11 denotes a cylindrical outer shell portion (hereinafter referred to as a core outer shell), which is not shown in the figure, but an inner structure 15 such as a shroud is provided on the inner lower portion thereof, and an upper portion thereof. A device 14 such as a separator or a dryer is installed in the apparatus. 12 is a fuel pool, 13 is a pool for temporary storage (hereinafter referred to as DS pool), which is adjacent to both sides of the core shell 11, and contains water which is an excellent radiation shield. .

  In the DS pool 13, equipment taken out from the core shell 11 for replacement work accompanying replacement of equipment is temporarily placed. In the example shown in the figure, equipment 14 such as a separator and a dryer at the upper part of the core is temporarily placed in the right part. These devices 14 are once taken out and temporarily placed in order to take out the lower core device.

  On the other hand, in the left part of the figure, the in-furnace structure 15 to be cut is taken out from the core shell 11 and temporarily placed. The furnace internal structure 15 is disposed of after being removed, but is highly radioactive, so it must be stored in a waste storage container. For this purpose, it is cut into a size that can be stored in the waste storage container. To do.

  This cutting operation is performed in the DS pool 13 underwater. That is, the in-furnace structure (hereinafter, referred to as a shroud) 15 that is the workpiece is temporarily placed on the left side of the DS pool 13 in the drawing, and the workpiece is cut in water. Therefore, this portion of the DS pool 13 (the left portion in the figure) is called a cutting work area. On the other hand, the part that is not cut and is used for temporary placement of the device 14 (the right-hand side portion of the DS pool 13 in the figure) is referred to as a temporary placement area. A support frame 16 for receiving the temporarily placed device 14 is provided inside the right side of the DS pool 13 in the figure corresponding to the temporary placement area, and a shield 17 for the outside is provided on the upper surface. Yes.

  Here, since FIG. 1 is drawn in a state in which the inside is seen through, the outer shape is unknown, but in reality, the core outer shell 11, the fuel pool 12, and the DS pool 13 that form a cylindrical shape are thick concrete. An outer shell is formed by the wall. Accordingly, a floor surface having a considerable width dimension is formed on the upper surface (so-called edge portion) of the peripheral portion of the DS pool 13.

  A carriage rail 18 is installed on the floor of the edge on both sides of the DS pool 13 in the width direction. On this rail 18, a cutting carriage 19 and a first lifting machine 20 are respectively connected to the rail 18. It is mounted so as to be movable along the laying direction.

  The cutting carriage 19 has a moving pedestal that traverses the DS pool 13, and this moving pedestal suspends a cutting head that cuts the workpiece 15 so as to move up and down, although not shown. This cutting head is configured to be able to travel along the length direction of the moving gantry, and in combination with the moving direction of the moving gantry itself (laying direction of the rails 18), the cutting head is moved in the DS pool 13. It can be moved to any position in the cutting work area.

  The first lifting machine 20 also has a moving pedestal that crosses the DS pool 13, and this moving pedestal is provided with two suspension supports that are movable along the length direction, although not shown. It has been. One of these suspension supports suspends a holding tool for holding the cut portion of the workpiece 15 in the DS pool 13 so as to move up and down during the cutting operation. In addition, the other suspension support part is arranged near the cutting part, and can move up and down a recovery tool for recovering secondary substances (cutting powder, abrasives used for cutting, etc.) that occur secondary to the cutting operation. It is suspended from. These holders and recovery devices can be moved to arbitrary positions in the DS pool 13 depending on the moving direction of the first lifting machine 20 and the moving direction of each suspension support on the moving frame.

  A storage container 22 is installed in the DS pool 13 and stores a cut piece cut from the workpiece 15 by a cutting operation. This cutting piece is held by the holding tool suspended from the first lifting machine 20 at the time of cutting work, and is carried in after the cutting by the movement of the holding tool holding the cutting piece. Reference numeral 23 denotes a recovery device, and reference numeral 24 denotes a recovery tank, which are also installed in the DS pool 13, respectively, to recover substances (cutting powder, abrasives used for cutting, etc.) that are generated secondaryly during the cutting operation. That is, at the time of cutting, a recovery device suspended from the first lifting machine 20 is arranged near the cutting portion, and the recovery device 23 is connected to the recovery device by a suction hose (not shown). Through this collection tool, the cutting powder, the abrasive used for cutting, and the like are collected by suction and stored in the collection tank 24.

  2 and 3, 26 is a large overhead traveling crane, which is installed on the ceiling of the power plant building, and is used for transporting large heavy objects such as core equipment.

  In such a nuclear facility, in the present invention, as shown in FIG. 4, a second lifting machine 27 is disposed in the vicinity of the recovery tank 24, and the recovery tank 24 and the recovery device 23 can be moved as appropriate. Configured to be possible.

  As the second lifting machine 27, a jib crane including a lifting arm 27a and a base portion 27b that holds one end of the arm 27a is used. In the example of FIG. 4, the base portion 27 b of the jib crane 27 is integrally attached and fixed to the side surface portion of the shield 17 that shields the upper surface of the temporary storage area of the DS pool 13.

  Here, the jib crane 27 has a structure in which a base portion 27b is fixed and an I-shaped beam serving as an arm 27a rotates around one end. Then, by fixing the base portion 27b to the side surface of the shield 17, the objects in the DS pool 13 can be obtained without obstructing the trajectory of the first lifting machine 20 and the cutting carriage 19 having the gate-shaped support frame on the upper side. Can be arbitrarily moved. By using this jib crane 27, the recovery device 23 and the recovery tank 24 can be connected to the vicinity of the cutting point without interrupting the cutting operation of the in-furnace structure 15 that is operated using the first lifting machine 20 and the cutting carriage 19. It is possible to move to an arbitrary position or to exchange the collection tank 24.

  In the above configuration, when replacement work of the reactor internal structure 15 is performed, the upper equipment 14 (dryer, separator, etc.) in the core shell 11 is taken out by the overhead crane 26 shown in FIGS. Temporary placement is performed in the temporary placement area on the right side of the pool 13 in the figure. Since these superstructures are also highly radioactive, they are installed in water, which is an excellent radiation shield, and a shield 17 is also installed on the upper surface of this temporary storage area using an overhead crane 26, Shield from the outside.

  Next, the core structure 15 to be cut, for example, the shroud, is taken out from the lower part of the core shell 11 using the overhead crane 26 and temporarily placed in the water of the DS pool 13. The shroud 15 is cut into fine units for disposal. For this reason, the workpiece 15 is temporarily placed as a workpiece 15 in the cutting work area (the left portion in the figure) in the DS pool 13.

  In the cutting operation, first, the first lifting machine 20 is operated, and the cut portion of the workpiece 15 is held by the holding tool suspended from the movable frame. Next, similarly, the first lifting machine 20 is operated, and the recovery tool is arranged near the cutting portion. This collection device is formed in a flat hood shape, and a suction hose from the collection device 23 is connected to the center of the collection device. For this reason, if it opposes near a cutting part, substances, such as cutting powder generated at the time of cutting mentioned below, and the abrasive used for cutting, can be caught efficiently and collected.

  Next, the cutting carriage 19 is operated, and the cutting head that is suspended in water is made to face the cutting target portion of the workpiece 15. The cutting head is equipped with a tool that directly cuts the object 15 to be cut. For example, a high-pressure water is sprayed on a portion to be cut together with a cutting abrasive, and a nozzle-like one that cuts the target portion is used. Use. Needless to say, the present invention is not limited to the nozzle-shaped cutting head, and any device that can cut the workpiece 15 such as a shroud in water may be used.

  Thereafter, the actual cutting operation is started. When a nozzle-like cutting head is used, the periphery of the portion fixed by the fixture is moved while spraying high-pressure water containing an abrasive on the portion to be cut. Cut the enclosed part. At this time, a large amount of materials such as cutting powder and abrasives used for cutting are generated from the cutting location, but these are sucked and captured by a recovery tool arranged oppositely near the cutting location and collected in the recovery tank 24 by the recovery device 23. To be recovered. Further, since the cut piece cut by this cutting work is held by the holder, the cut piece is transferred into the storage container 22 by operating the first lifting machine 20, and the holding by the holder is released. The cut pieces are stored in the storage container 22.

  Thereafter, the above operation is repeated to sequentially cut the objects to be cut, and the cut pieces are stored in the storage container 22.

  During such a cutting operation, the position of the recovery device 23 or the recovery tank 24 may have to be moved depending on the cutting position. If the collection tank 24 becomes full, the cutting operation cannot be continued unless the collection tank 24 is immediately replaced. In such a case, by using the jib crane 27 as the second lifting machine, the recovery device 23 and the recovery tank 24 can be moved or the recovery tank can be replaced immediately.

  Conventionally, since this jib crane 27 was not provided, the cutting operation must be temporarily stopped and the first lifting machine 20 must be operated to move the collection device 23 and the collection tank 24 or to exchange the collection tank. . If the cutting work is interrupted in this way, it is inevitable that the construction period will be prolonged, for example, further preparation for the cutting work is required even when the cutting work is resumed.

  On the other hand, in the present invention, since the jib crane 27 is provided, the recovery device 23 and the recovery tank 24 can be moved or the recovery tank can be exchanged immediately. Can be shortened.

  Next, the embodiment shown in FIG. 5 will be described. In this embodiment, the base 27b of the jib crane 27, which is the second hoist, is attached and fixed to the support base 16 of the temporary storage device 14 installed in the temporary storage area of the DS pool 13. That is, the support frame 16 is installed in the vicinity of the collection tank 24 in the adjacent cutting work area, and by attaching and fixing the base portion 27b of the jib crane 27 to the upper part of the support frame 16 as shown in the figure, An object in the DS pool 13 can be moved without obstructing the trajectory of the first lifting machine 20 or the cutting carriage 19 having the gate-shaped support frame at the top. Then, by using this jib crane 27, the recovery device 23 and the recovery tank 24 can be cut without interrupting the cutting operation of the in-furnace structure 15 using the first lifting machine 20 and the cutting carriage 19. It is possible to move to an arbitrary position in the vicinity of the place or to exchange the collection tank 24.

  Next, the embodiment shown in FIG. 6 will be described. In this embodiment, a base 27b of a jib crane 27, which is a second hoist, is attached and fixed to a support member (not shown) of a rail 18 installed on the edge floor of the DS pool 13.

  In this way, by attaching and fixing the base portion 27b of the jib crane 27 to the support member of the rail 18 on the edge floor of the DS pool 13, the first lifting machine 20 and the cutting carriage 19 having the portal support frame on the upper side. The object in the DS pool 13 can be moved without disturbing the trajectory. And without interrupting the cutting operation of the in-furnace structure 15 using the first lifting machine 20 and the cutting carriage 19, the recovery device 23 and the recovery tank 24 can be moved to an arbitrary position near the cutting location, The recovery tank 24 can be exchanged.

  Next, the embodiment shown in FIG. 7 will be described. In this embodiment, a base portion 27b of a jib crane 27, which is a second lifting machine, is attached and fixed to the inner wall surface of the DS pool 13. That is, as described above, since the outer shell of the DS pool 13 is formed of a thick concrete wall, the base portion 27b of the jib crane 27 is attached to the concrete wall surface.

  By comprising in this way, the thing in the DS pool 13 can be moved, without interfering with the track | orbit of the 1st lifting machine 20 and the cutting trolley | bogie 19 which have the gate-shaped support stand in the upper part. And without interrupting the cutting operation of the in-furnace structure 15 using the first lifting machine 20 and the cutting carriage 19, the recovery device 23 and the recovery tank 24 can be moved to an arbitrary position near the cutting location, The recovery tank 24 can be exchanged.

  Next, the embodiment shown in FIG. 8 will be described. In this embodiment, a base 27b of a jib crane 27, which is a second lifting machine, is installed on the floor surface of the upper surface of the edge of the DS pool 13. That is, as described above, the outer surface of the DS pool 13 is formed of a thick concrete wall, so that a floor surface having a considerable width dimension is formed on the upper surface of the edge of the DS pool 13. Therefore, the base 27b of the jib crane 27 is erected and fixed on the edge floor.

  Even if comprised in this way, the thing in the DS pool 13 can be moved, without disturbing the track | orbit of the 1st lifting machine 20 which has the gate-shaped support stand in the upper part, and the cutting trolley | bogie 19. FIG. And without interrupting the cutting operation of the in-furnace structure 15 using the first lifting machine 20 and the cutting carriage 19, the recovery device 23 and the recovery tank 24 can be moved to an arbitrary position near the cutting location, The recovery tank 24 can be exchanged.

It is a perspective view which shows the structure of a general nuclear reactor facility transparently. It is a top view of FIG. It is a front view of FIG. It is a perspective view which shows one Embodiment of the cutting equipment of the nuclear reactor structure by this invention. It is a perspective view which shows embodiment which attached the jib crane used for this invention to the support stand for temporary placement. It is a perspective view which shows embodiment which attached the jib crane used for this invention to the temporary storage pool inner wall surface. It is a perspective view which shows embodiment which attached the jib crane used for this invention to the support member of the rail. It is a perspective view which shows embodiment which attached the jib crane used for this invention on the floor surface of the edge part upper surface of a pool.

Explanation of symbols

11 Core Outer 12 Fuel Pool 13 Temporary Pool (DS Pool)
14 Dryer, separator 15 Object to be cut (furnace structure)
DESCRIPTION OF SYMBOLS 16 Supporting stand for temporary placement 17 Shield 18 Rail for trolley 19 Cutting trolley 20 First lifting machine 22 Storage container 23 Collection device 24 Collection tank 26 Overhead crane 27 Second lifting machine 27a Arm part 27b Base part

Claims (6)

Is installed in the core outer side, the water is contained water therein temporarily placed the object to be cut, have rows cutting operation for object to be cut in the water, the area cutting operation area close to the core outer And a pool in which a region far from the core shell is defined as a temporary storage region,
Rails installed at the upper edge of the pool;
An overhead crane for moving the object to be cut from the core shell to the temporary storage area of the pool;
A cutting carriage having a gate-shaped support frame that is movably installed on the rail and suspends a cutting head capable of cutting the workpiece;
On the rails, the installed core shell and the position between the cutting carriage, said secondary occurring substances with the retaining Gu及 beauty the cutting unit is placed near the cutting operation to hold the cut portion of the object to be cut A first lifting machine having a gate-shaped support frame for hanging a collection device for collecting
A temporary support stand provided in the temporary storage area of the pool;
A shield installed on the upper surface of the temporary storage area of the pool ;
A base is fixed to a side surface of the shield, the support stand for temporary placement, or an inner wall surface of the pool, and a second hoist having an arm pivotably attached to the base,
Cutting equipment of the cutting carriage and reactor structures is characterized in that it possible to move the recovery tank without interfering with the trajectory of the first crane with a pre-Symbol gantry support cradle.   The second lifting machine is a jib crane composed of a lifting arm and a base that holds one end of the arm, and the base shields the upper surface of the temporary storage area adjacent to the cutting work area of the pool. The facility for cutting a nuclear reactor structure according to claim 1, wherein the facility is fixed by being attached to a body.   The second lifting machine is a jib crane composed of a lifting arm and a base part that holds one end of the arm, and the base part is provided in a temporary placement area of the pool adjacent to the cutting work area. The facility for cutting a nuclear reactor structure according to claim 1, wherein the facility is fixed on a support frame for placement.   The second lifting machine is a jib crane composed of a lifting arm and a base that holds one end of the arm, and the base is used as a support member for a rail for a cutting carriage installed on the upper surface of the edge of the pool. The facility for cutting a nuclear reactor structure according to claim 1, wherein the facility is fixed by being attached.   The second lifting machine is a jib crane comprising a lifting arm and a base part holding one end of the arm, and the base part is attached and fixed to the inner wall surface of the pool. The reactor structure cutting equipment described.   The second lifting machine is a jib crane composed of a lifting arm and a base that holds one end of the arm, and the base is erected and fixed on the edge floor of the pool. The reactor structure cutting equipment according to claim 1.

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