JPH095484A - Method and device for handling nuclear instrumentation tube in nuclear reactor - Google Patents

Abstract

(57) [Summary] [Purpose] In the nuclear instrumentation tube exchange work in the reactor, introducing a nuclear instrumentation tube exchange device installed in the reactor simplifies the work requiring skill and shortens the process by eliminating the moving step. And to reduce incidental work. [Structure] A fuel support fitting and a shape that can be installed in one section of the upper lattice plate and a hook, and has an opening on the side surface of the body,
A used nuclear instrumentation tube storage basket equipped with a handle that has a mechanism for preventing the nuclear instrumentation tube stored when moving from falling off. It has a shape that can be installed with the upper lattice plate near the furnace wall, fuel support metal fittings, and furnace wall structure, and can install all the new nuclear instrumentation pipes to be replaced, and the new nuclear instrumentation pipes can be remotely operated from the refueling machine. A new nuclear instrumentation tube holder that can be separated. A nuclear instrumentation tube exchange method using the above two nuclear instrumentation tube exchange devices.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for handling a nuclear instrumentation pipe in the operation of replacing a nuclear instrumentation pipe in a reactor pressure vessel and an instrument used for the handling.

[0002]

2. Description of the Related Art Nuclear instrumentation tube replacement work that has been performed conventionally has been performed in the following work steps.

(A) Removal of used nuclear instrumentation pipes (omission of pedestal work) is shown in FIG. 16, an outline of the work is shown in FIG. 19, an upper end / lower end enlarged view of the nuclear instrumentation pipes is shown in FIG. The details of the steps are shown below.

In step 61, the measuring instrument handling tool 15 attached to the rotary jib crane 12 of the refueling machine 11 is hung in the furnace.

At step 62, the used nuclear instrumentation tube 1 is gripped by the measuring instrument handling tool 15.

At step 63, the plunger 52 of the used nuclear instrumentation tube 1 is removed from the upper lattice plate 3, and the used nuclear instrumentation tube 1 is removed.
To 2m above the surface of the water.

In step 64, the auxiliary winding equipment 1 for the overhead crane
Refueling machine 1 with hydraulic clamp 16 suspended from 4
Grab the used nuclear instrumentation tube from 1.

In step 65, the hydraulic clamp 16 is moved to the spent fuel pool 8 and the nose piece 53 of the nuclear instrumentation pipe is moved.
Side to be on spent fuel pool canal 7.

In step 66, the incore manipulator 1
Grab the nosepiece 53 with 7 and lift to the surface of the water.

In step 67, the nosepiece 53 is gripped by hand while the plunger 52 side gripped by the hydraulic clamp 16 is lowered to the bottom of the spent fuel pool 8 and moved to the north side wall surface of the spent fuel pool 8.

In step 68, the nosepiece 53 side is fixed to the internal structure of the spent fuel pool 8.

In step 69, the hydraulic clamp 16 is disconnected from the used nuclear instrumentation tube 1.

After the work of step 66 is completed, the second one is removed from step 61 in the same step.

In step 70, the spent nuclear instrumentation pipe 1 is cut in the spent fuel pool 8 at any time.

(B) The new nuclear instrumentation tube installation work step is shown in FIG. 20, the work outline is shown in FIG. 21, and the contents of the work step in FIG. 20 are shown below.

In step 71, the nuclear instrumentation tube installation guide 19, the in-reactor lighting, etc. are installed on the upper grid plate 3.

In step 72, the new nuclear instrumentation tube holder 18 is set to 1
Install the new nuclear instrumentation tubes 2 of the number scheduled to be installed daily.

In step 73, the new nuclear instrumentation pipe holder 18 horizontally hung is moved vertically above the furnace by the auxiliary winding equipment 14 of the overhead crane, and then the upper end of the new nuclear instrumentation pipe holder 18 is brought to the water surface. Hang it down to a position 3 m above.

In step 74, the new nuclear instrumentation tube 2 is grasped by the measuring instrument handling tool 15 attached to the fixed auxiliary hoist 13 of the fuel changer 11, and the new nuclear instrumentation tube holder 18 is manually operated from above the fuel changer 11. Detach.

In step 75, the new nuclear instrumentation tube holder 18 is moved to the dryer / separator pit 10 to prepare for the next installation.

In step 76, the new nuclear instrumentation tube 2 is inserted along the nuclear instrumentation tube installation guide 19.

In step 77, the seat portion is flushed. (Pedestal work) In step 78, measuring instrument handling tool 1
Check seating with 5.

In step 79, the measuring instrument handling tool 15 is disconnected and the processing ends.

In step 80, the nuclear instrumentation tube installation guide 19
To move.

In step 81, the new nuclear instrumentation tube holder 18 is moved from the dryer / separator pit 10 onto the furnace.

After the second line, steps 74 to 81 are repeated.

After the mounting process is completed in step 82, the new nuclear instrumentation tube holder 18 is taken out of the reactor water and decontaminated.

The number of new nuclear instrumentation tube holders 52 that can be mounted is 1
If the number of the new nuclear instrumentation tubes is less than the planned number of attachments per day, the new nuclear instrumentation tube holder 18 is taken out of the reactor water on the way and the new nuclear instrumentation tube 2 is attached after decontamination.

In such exchange work, there are many steps involving movement and re-grabbing of the nuclear instrumentation tube, and many operations require skill.

Known examples in which the number of steps involved in moving and re-grabbing are small are Japanese Patent Laid-Open Nos. 60-144695 and 56-1267.
There are contents disclosed in Japanese Patent Laid-Open No. 99 and Japanese Patent Laid-Open No. 56-137291.

First, according to the contents disclosed in JP-A-60-144695, a used nuclear instrumentation tube cutting processing device having a storage container that can be installed on an upper lattice plate and having a cutting function is provided. It is said that the nuclear instrumentation tubes vertically pulled out from the upper lattice plate are sequentially cut in the furnace, and after the cutting is completed, they are collectively stored in a storage container and can be moved to the spent fuel pool together with the storage container.

Further, JP-A-56-126799 and JP-A-56-126
According to the content disclosed in Japanese Laid-Open Patent Publication No. 137291, a plurality of notches, on which a plurality of nuclear instrumentation tubes are mounted, are combined in a multi-step manner with a plurality of disks provided around the entire outer circumference, and the nuclear instrumentation from the notches There is a holder for the nuclear instrumentation tube equipped with a steadying and pressing means to prevent the tube from falling out, and a plurality of nuclear instrumentation tubes stored in the notches are carried into the reactor pressure vessel at the same time as the holder. It is then transferred from the holder to the nuclear instrumentation tube installation position in the reactor pressure vessel. JP-A-56-126799
In the one disclosed in Japanese Patent Publication No. 56-137291, the orientation of the notch cannot be changed in the reactor, but in the one disclosed in Japanese Patent Publication No. 56-137291 the holder for the nuclear instrumentation tube is changed by rotating the disc. The removal position from can be fixed.

[0033]

In the conventional nuclear instrumentation tube removal work in the conventional nuclear instrumentation tube replacement work having the work steps shown in FIG. 16, a step of moving each used nuclear instrumentation tube (see (a) 65 above). (Indicating steps 69 to 69) must be repeated for the replacement target, so that the replacement process becomes long and a dedicated worker is required. Further, the re-gripping work by the hydraulic clamp 16 (refer to the above (a) 64)
Requires expert skills, so full-time workers are required.

Next, in the conventional nuclear instrumentation tube replacement work shown in FIG.
Since the moving steps (referring to the steps (b) 75 and 81 described above (b)) are repeated for each book for the replacement target, a dedicated worker is required. Further, when the worker leaves the site for lunch, scheduled work, or the like, the new nuclear instrumentation pipe holder 18 cannot be hung in the reactor water, so it is necessary to remove it from the water for decontamination.

The contents disclosed in Japanese Patent Laid-Open No. 60-144695, which is another conventional example, is that the removal and cutting of the nuclear instrumentation pipes are carried out in the furnace, and the nuclear instrumentation pipes are collectively moved to the spent fuel pool. However, there are the following problems.

(1) There is no record of cutting the structure in the furnace, and if the structure is cut in the furnace,
When the partial fuel is taken out, the fuel assembly is loaded in the furnace, and fragments may enter the gap between the fuel assemblies, which is a serious problem.

(2) The conventional operation for exchanging nuclear instrumentation tubes does not include the task of cutting the nuclear instrumentation tube, and can be performed at any time within the regular inspection after the completion of the exchanging operation, and is therefore treated separately. Therefore, performing the cutting operation of the nuclear instrumentation tube within the exchange operation means that the nuclear instrumentation tube exchange step is significantly extended.
Since the nuclear instrumentation tube replacement work is a critical path at the time of regular inspection, the delay of this work leads to the delay of the entire regular inspection process.

Further, Japanese Patent Laid-Open Nos. 56-126799 and 56
According to the contents disclosed in the −137291 publication, since a plurality of nuclear instrumentation tubes can be collectively carried into the reactor containment vessel by the holder, the moving distance of each nuclear instrumentation tube can be shortened. However, in JP-A-56-126799, since the take-out positions of the nuclear instrumentation tubes are scattered around the outer periphery of the disk, the means for taking out and moving the nuclear instrumentation tubes from the holder and the removal thereof. It is necessary to carefully move around the disk so that the nuclear instrumentation tube does not interfere with the disk, and in the case of JP-A-56-137291, a heavy disk is placed at the position where the nuclear instrumentation tube is taken out from the holder. Since it is troublesome to rotate up to, and the operation of taking out the nuclear instrumentation tube cannot be done unless the rotation position is matched, skill and labor are required. These problems also occur when the retainer is diverted to the retainer when removing the used nuclear instrumentation pipe, and especially the work of putting the used nuclear instrumentation pipe in the notch is done by using reactor water in the reactor pressure vessel. If it is satisfied, it will be an underwater operation, which requires skill and time.

Therefore, an object of the present invention is to easily carry out the handling of the nuclear instrumentation pipe in the replacement work of the nuclear instrumentation pipe in the reactor pressure vessel.

[0040]

[Means for Solving the Problems] A first means for achieving the above object is to provide a reactor pressure vessel in which reactor water is present.
Carrying in a basket having an opening extending to the upper end on the side surface, inserting the basket into the upper lattice plate in the reactor pressure vessel and installing the bottom portion on the fuel support fitting, and thereafter,
The spent nuclear instrumentation pipe in the reactor pressure vessel is moved by the refueling machine to be stored in the basket through the opening on the side surface of the basket, and the plurality of the plurality of the inside of the basket are stored by repeating the storing work. Stores used nuclear instrumentation tubes,
Next, it is a method of removing the nuclear instrumentation pipe in the reactor, in which the basket and the plurality of the used nuclear instrumentation pipes are moved together into the pool at the storage location.

Similarly, in the second means, in the first means, the plurality of used nuclear instrumentation tubes are stored in the basket, and at any time before the core confirmation step in the reactor pressure vessel. The basket and the plurality of the used nuclear instrumentation tubes are moved together into the pool at the storage location, and the used nuclear instrumentation tubes in the pool are cut and cut in the pool at any time thereafter. It is a method of removing the nuclear instrumentation pipe in a nuclear reactor which stores the used nuclear instrumentation pipe in the pool.

Similarly, the third means is to install a new nuclear instrumentation pipe holder in which a plurality of new nuclear instrumentation pipes are detachably mounted on one side in the reactor pressure vessel in which reactor water exists in the reactor pressure vessel. After being carried in, the new nuclear instrumentation tube holder is inserted into the upper lattice plate in the reactor pressure vessel so that the one side faces the installation position of the new nuclear instrumentation tube as much as possible, and the bottom portion is installed on the fuel support metal fitting. Of the nuclear instrumentation pipe in the reactor, which is repeated by moving the new nuclear instrumentation pipe from the new nuclear instrumentation pipe holder to the installation position with a refueling machine and installing the new nuclear instrumentation pipe at the installation position. This is the installation method.

Similarly, the fourth means removes the used nuclear instrumentation tube from the reactor pressure vessel by the method of removing the nuclear reactor internal instrumentation pipe by the first means, and after the removal, the nuclear reactor internal core by the third means is removed. It is a nuclear reactor instrumentation pipe replacement method in which the used nuclear instrumentation pipe is replaced with a new nuclear instrumentation pipe by installing a new nuclear instrumentation pipe by the instrumentation pipe installation method.

Similarly, the fifth means is a basket body having an external thickness that allows passage through the lattice of the upper lattice plate in the reactor pressure vessel from the lower end to the middle of the upward direction, and A side opening having a width larger than the thickness of the nuclear instrumentation tube, which is opened from the middle to the upper end of the basket body, and is movable on the other side of the basket body in the vertical direction of the basket body. A slide rod rotatably mounted at least at the upper end of the movement, a handle rotatably attached to the slide rod, and a slide rod disposed in the basket body and having an angle with the slide rod. Use with a fixedly mounted support and a transfer hook mounted on the side of the basket body. It is a storage basket of Sumikakukei Sokan.

Similarly, in the sixth means, in the fifth means, a fixing hook hooked on the upper lattice plate is provided on the side surface of the basket body, and the bottom of the basket body is provided with a circle of a fuel support fitting in the reactor pressure vessel. A storage basket for used nuclear instrumentation pipes, characterized in that it has a basket installation guide projecting downwardly installed in the hole.

Similarly, the seventh means includes a plurality of recesses provided on one side surface of the holder body to surround the nuclear instrumentation tube, and a position adjacent to the recesses for closing the opening of the recesses and a position for opening the recesses. A nuclear instrumentation tube holding plate mounted rotatably between
Nuclear instrumentation tube holding provided with a slit provided in the lower part of the holder body for passing an upper lattice plate in the reactor pressure vessel, and a plurality of hooks attached to the holder body at intervals in the vertical direction It is a tool.

Similarly, in the eighth means, in the seventh means, the retainer body is provided with a fixing stay projecting in the other side direction to engage with the reactor pressure vessel, and the bottom surface of the retainer body is provided with an atom. A storage basket for used nuclear instrumentation pipes, characterized in that it is provided with a downwardly projecting holder installation guide installed in a round hole of a fuel support fitting in a reactor pressure vessel.

[0048]

According to the first means, the basket is securely supported by the fuel support fitting and the upper lattice plate, and the spent nuclear instrumentation pipe is conveyed to the basket side by the fuel changer, and the spent nuclear instrumentation pipe is Is passed through the opening on the side of the basket and carried into the basket for storage. In this storage work, if the lower end of the used nuclear instrumentation tube passes through the opening on the side surface of the basket, it is simply hung and the used nuclear instrumentation tube is stored in the basket.
The storage operation is easier than storing the used nuclear instrumentation pipe in a plurality of notches that are separated from each other. By repeating this storage operation, a plurality of used nuclear instrumentation tubes are stored in the basket. After that, all the used nuclear instrumentation pipes together with the basket are moved into the pool at the storage location, and the used nuclear instrumentation pipes that should be replaced with the new nuclear instrumentation pipes are removed from the reactor pressure vessel. It is possible to obtain the effect of being able to quickly shift to the installation work of the pipe. You can move immediately, but you can move at any time before the core confirmation.
(It does not affect the work of installing new nuclear instrumentation pipes.) According to the second means, the cutting work of the used nuclear instrumentation pipes is carried out in the pool outside the reactor pressure vessel by the first means, and the cutting debris accompanying Since it is not left in the reactor pressure vessel and the cutting work is performed outside the reactor pressure vessel, it can be performed at any time separately from the work inside the reactor pressure vessel, and the periodic inspection that involves the work inside the reactor pressure vessel. Do not delay the work process. Further, if it is desired to perform the cutting work immediately, a plurality of used nuclear instrumentation pipes are brought into the cutting work site outside the reactor pressure vessel at once, so that the cutting work can be continued and the efficiency can be improved.

According to the third means, a plurality of new nuclear instrumentation tubes are attached to the new nuclear instrumentation tube holder. Insert the holder into the upper grid plate in the reactor pressure vessel (with the mounting surface facing the reactor core, that is, at the installation position of the new nuclear instrumentation tube with the mounting surface facing), and insert the upper grid plate and fuel support bracket. Securely support the holder with. After that, the refueling machine transfers the new nuclear instrumentation pipe from the holder to the installation position of the new nuclear instrumentation pipe and installs it. This installation work is repeated between the holder and the installation position of the new nuclear instrumentation tube. In the movement of the new nuclear instrumentation tube during this installation work, since the mounting surface is oriented to the installation position of the new nuclear instrumentation tube, there is no interference between the holder and the new nuclear instrumentation tube during movement, and the shortest route is possible. The effect is that the new nuclear instrumentation tube installation work that accompanies the replacement work can be performed without the skilled skill of interference avoidance operation.

According to the fourth means, by the combination of the action of the first means and the action of the third means, the spent nuclear instrumentation pipe is removed, and the replacement work with the installation of the new nuclear instrumentation pipe on the trace of the removal. It is possible to obtain the effect that the entire work can be performed easily in a short time.

According to the fifth means, the basket body is lifted by connecting a wire or rope to the handle and the moving hook. Since the lifting posture has two hanging points, the basket body can be changed between a horizontal posture in which the side surface opening of the body faces upward and a vertical posture. The basket body is inserted in the upper lattice plate halfway with the vertical suspension posture and installed in the reactor pressure vessel. A spent nuclear instrumentation tube can be received and stored in the basket body through the side opening of the body. During storage, the handle rotates and falls, retracts from above the upper opening of the basket body, and avoids accidents of interference between the used nuclear instrumentation pipe and the handle during storage work. Furthermore, during storage, the slide rod descends downward and the support also interlocks, so that the body does not block the side opening with the support. Therefore, the used nuclear instrumentation tube passes through the side opening of the body without being hindered by the support and is accommodated in the body. In this storage operation, if the lower end of the used nuclear instrumentation pipe has passed through the side opening of the body, the used nuclear instrumentation pipe is stored in the body simply by hanging it down. The body containing the used nuclear instrumentation tube is pulled out from the upper lattice plate by lifting the handle. At this time, the handle rotates and stands up, and further rises together with the slide rod to avoid interference between the handle and the upper end of the stored nuclear instrumentation tube. As the slide rod rises, the support also rises up to the body side opening to prevent the stored nuclear instrumentation tube from falling down or largely protruding from the body side opening. When the body is hung horizontally, the slide rod rotates vertically with respect to the horizontal body.Therefore, as the slide rod rotates relative to the body, the support integrated with the slide rod is also provided. It is possible to obtain an effect of preventing the used nuclear instrumentation tube from falling off or coming off the body by being pressed against the used nuclear instrumentation tube in which the support is housed by rotating relative to the body.

According to the sixth means, in addition to the action of the fifth means, the fixing hook is caught on the upper lattice plate, and further, the basket installation guide at the bottom of the body fits into the round hole of the fuel support fitting. The effect is that the body is firmly installed in the furnace pressure vessel, the body is prevented from wobbling and falling during storage work, and the work can be smoothly promoted.

According to the seventh means, the new nuclear instrumentation tube is housed in the plurality of recesses formed on one side surface (mounting surface of the new nuclear instrumentation tube) of the holder body, and the tip end side of the recessed portion is prevented from falling off. The opening is closed by rotating the nuclear instrumentation tube holding plate. In this state, using the multiple hooks as suspension points, suspend the retainer body together with the multiple new instrumentation tubes and hang it down in the reactor pressure vessel.Pass the lattice plate of the upper lattice plate through the slit of the retainer body and the retainer body and the upper part. The retainer body is installed in the reactor pressure vessel by engaging the lattice plate. When installing it, orient it so that the one side face (mounting face of the new nuclear instrumentation tube) faces the replacement work position. After that, the position of the nuclear instrumentation tube holding plate is rotated so that the tip side opening of the recess is opened, and the new nuclear instrumentation tube is moved from the holder body to the installation position (replacement work position) of the new nuclear instrumentation tube. To be used for replacement work. At the time of the movement, since the above-mentioned mounting surface faces the replacement work position, the movement can be made in the shortest path without changing the orientation of the holder body in the middle, and the avoidance operation of the interference of the holder body is not involved. The action is obtained.

According to the eighth means, in addition to the action of the seventh means, the retainer installation guide at the bottom of the retainer body fits into the round hole of the fuel support fitting, and the fixing stay engages with the reactor pressure vessel. As a result, the holding body in the reactor pressure vessel can be installed in a stronger state, and the body can be prevented from wobbling and collapsing at the time of work, and the work can be smoothly promoted.

[0055]

[Embodiment] This used nuclear instrumentation tube storage basket 27 is shown in FIG.
As shown in, the entire product is made of stainless steel and can be stored in water.

Since it is installed on the upper lattice plate 3 in the reactor pressure vessel A filled with reactor water, it is necessary to reduce the weight, and the stainless steel net 3 is used for a portion where strength is not so required.
1 or use a stainless steel plate lightened by machining.

A light and water resistant material such as aluminum or titanium steel may be used.

Since it is not necessary to store the entire nuclear instrumentation tube,
The shape is such that it can be installed in one section of the grid plate without the top lid.

A side opening 37 is provided on the side surface of the used nuclear instrumentation tube storage basket 27 at an angle of 90 ° or less when viewed from the top so that the nuclear instrumentation tube having a total length of more than 13 m is not exposed from the water surface when pulled out in the longitudinal direction.

As a result, the moving distance of the used nuclear instrumentation tube 1 in the vertical direction is reduced to facilitate storage.

In order to fix the fuel support fitting 6 on the core support plate 4 (see FIG. 18) and the upper lattice plate 3 in the reactor pressure vessel A, the bottom 29 of the basket body can be stably placed on the fuel support fitting 6. Basket installation guide 30 (Fig. 10
As shown in FIG. 9, fixing hooks 39 that can be fixed to the upper lattice plate 3 are attached to the side surfaces of the basket body 28 in four directions when viewed from above.

The moving hook 38 required for moving the spent nuclear instrumentation tube storage basket 27 was lifted by the basket grasping tool 21 attached to the fuel changer 11 and rolled over. At this time, in order to prevent the stored items from falling, the side opening 37 is attached at a position that faces upward.

The moving hook 38 has such a size that it does not interfere with the lattice plate when the used nuclear instrumentation tube storage basket 27 is installed on the upper lattice plate 3.

When the moving hook 38 is connected with a wire,
Since the side opening 37 may be closed when the used nuclear instrumentation tube 1 is stored, it is connected by a rope that can be loosened on the upper lattice plate 3.

The basket body 28 has a fuel changer 11
A handle 32 that can be grasped by the basket grasping tool 21 attached to is installed.

This handle 32 corresponds to the slide rod 3
3, the support 36 and the guide rail 35 formed on the side surface of the basket body 28, and the handle 32 is in the most contracted state when the used nuclear instrumentation tube is stored.
Defeat him.

As shown in FIG. 8, the basket gripper 21 has a structure in which the handle 32 can be inserted from the side, and the movement of the cylinder 43a operated by the air pressure supplied by the hose 24 in order to prevent the handle 32 from falling off during movement. It has a stopper 23 that operates in the vertical direction, and is provided with an attachment structure 25 that is attached to the rotary jib crane 12 of the fuel changer 11.

As shown in FIG. 22, the edge of the vertically long slot (vertical direction in FIG. 7) formed in the side surface of the basket body is used as the guide rail 35, and the slide rod 33 is used.
The slider 33 a fixed together with the support 36 is guided so as to be movable up and down without coming off from the guide rail 35.

The handle 32 is attached to the upper end of the slide rod 33.
It is rotatably attached by 2a.

When the spent nuclear instrumentation tube storage basket 27 is moved, the handle 32 is pulled up by using the basket grip 21 attached to the refueling machine 11.
As shown in (a), the support 36 is also pulled up along the guide rail 35 to close the side opening 37, so that the used nuclear instrumentation tube 1 can be prevented from falling off.

After the slide rod 33 is fully extended, the rope attached to the moving hook 38 is wound up and hung horizontally, and the support 36 fixes the used nuclear instrumentation tube 1 from above as shown in FIG. 11 (b). Because it comes to hold down,
It is possible to prevent the instrumentation pipe from falling off during movement.

The new nuclear instrumentation tube holder 40 installed in the reactor pressure vessel A of the present invention is made entirely of stainless steel as shown in FIG. 12, and is compatible with use in the reactor pressure vessel A in water. Since it is installed on the upper lattice plate 3 and the fuel support fitting 6 in the reactor pressure vessel A, the weight is reduced as compared with the conventional one.

A lightweight and water resistant material such as aluminum or titanium steel may be used.

As shown in FIG. 12, the new nuclear instrumentation pipe holder 40 installed in the reactor pressure vessel A can accommodate all the nuclear instrumentation pipes to be replaced at the time of regular inspection, and the upper lattice near the wall of the reactor pressure vessel A can be installed. The shape that can be installed on the plate 3 is used, and the surface facing the wall of the reactor pressure vessel A is difficult to separate the new nuclear instrumentation tube 2 and the workability is poor, so it is mounted on other surfaces except that surface.

The new nuclear instrumentation tube holder 40 installed inside the reactor pressure vessel A has a slit 49 for straddling the upper lattice plate 3.
And a bottom part (see FIG. 13) having a holder installation guide 48 which can be stably placed on the fuel support fitting 6 and is installed in the reactor pressure vessel A.

At this time, since the position above the position fixed by the upper lattice plate 3 becomes longer, the structure (head bolt hole etc.) on the wall of the reactor pressure vessel A and the upper part of the holder body 41 are fixed as a fall prevention measure. The fixing stay 44 that can be attached is attached.

This fixing stay 44 is, as shown in FIG. 1, a bolt 44a to the existing head bolt hole on the wall of the reactor pressure vessel A.
Fixed by.

Conventionally, the new nuclear instrumentation pipe holder 18 was hung by the auxiliary winding equipment 14 of the overhead crane, and the instrument handling tool 15 was used to grasp the new nuclear instrumentation pipe 2 on the surface of the water to disconnect the new nuclear instrumentation pipe 2. Since the nuclear instrumentation pipe holder 40 installed in the reactor pressure vessel A is placed lower than the conventional one in order to avoid interference with the refueling machine 11, it is necessary to facilitate remote operation.

Head 43 of new nuclear instrumentation tube disconnect lever 42
14 is a cornered shape as shown in FIG. 14, and a disconnecting jig 20 (see FIG. 14) having a socket-shaped tip having the same shape as that of the same is attached to the disconnecting lever head 43 from the top of the fuel changer 11. By rotating, the nuclear instrumentation tube holding plate 45 fixing the new nuclear instrumentation tube 2 can be easily rotated.

The rotation mechanism of the nuclear instrumentation tube holding plate 45 is shown in FIG.
As shown in FIG. 4 and FIG. 25, the head 43 of the new instrumentation tube disconnecting lever 42 is located above the upper end of the holder body 41 in operation, but the other portions are rotated inside the holder body 41. It is supported freely.

Worm gears 42a and 42b are attached in the middle of the new nuclear instrumentation tube disconnecting lever 42,
Gears 46a, 46b that rotate by meshing with the worm gears 42a, 42b are fixed to the rotary shafts 45a, 45b together with the respective nuclear instrumentation tube holding plates 45, and the rotary shafts 45a, 45b are attached to the holder body 41. It is rotatably installed.

Therefore, by mounting the separating jig 20 on the head 43 of the new nuclear instrumentation tube separating lever 42 and rotating it, the worm gears 42a and 42b, the gears 46a and 46b, and the rotating shafts 45a and 45b rotate in conjunction with each other. Then, the respective nuclear instrumentation tube holding plates 45, which are in a relationship of directly above and below, can rotate simultaneously.

As shown in FIG. 15, this nuclear instrumentation tube holding plate 4
Reference numeral 5 denotes a fan-shaped plate that can hold the new nuclear instrumentation tubes 2 on both sides of the holding plate, and the rotation direction of the holding plate 45 changes depending on the rotation direction of the separation lever 42, so that either one of the new nuclear instrumentation tubes 2 can be separated It

This operation can be easily carried out by separating the jig 20 from the refueling machine 11 and thrusting it into the reactor water.

When the new nuclear instrumentation tube holder 40 installed in the reactor pressure vessel A is set in or taken out from the reactor pressure vessel A, it is attached to the upper hook 50 attached to the upper end of the holder body 41 and the lower end. It is lifted using the lower hook 51.

The upper hook 50 is at the center of the body, but the lower hook 51 has the slit 49 at the center. Therefore, the upper hook 50 is mounted slightly offset from the center in consideration of the overall weight balance.

The upper hook 50 is hung by the rotary jib crane 12 of the refueling machine 11, and the lower hook 51 is hung by the auxiliary winding equipment 14 of the overhead crane.

Outside the reactor pressure vessel A, the suspension tube is horizontally hung with the mounting surface of the nuclear instrumentation pipe facing upward, and the suspension rope of the rotary jib crane 12 of the refueling machine 11 is placed at a predetermined position in the reactor pressure vessel A. Loosen it, set it upright, and then hang it straight down.

Removal is done in reverse.

The work steps when each of these is used alone are shown below.

(The numbers marked with * have been added or changed from the past.) (A) Fig. 2 shows the steps for removing used nuclear instrumentation pipes.

In step * 91, the rope attached to the moving hook 38 is hung from the auxiliary winding equipment 14 of the overhead crane, and the handle 32 held by the basket grip 21 attached to the fuel changer 11 is leveled. The used nuclear instrumentation tube storage basket 27 that has been lifted to the reactor pressure vessel A
Take it to the top, loosen the rope there and stand upright, and install it on the upper lattice plate 3 in the reactor pressure vessel A.

In step 92, the measuring instrument handling tool 15 attached to the refueling machine 11 is suspended in the reactor pressure vessel A.

In step 93, the used nuclear instrumentation tube 1 is grasped by the measuring instrument handling tool 15.

At step 94, the used nuclear instrumentation tube 1 is pulled out vertically.

In step * 95, the used nuclear instrumentation tube storage basket 27 is stored.

After the second line, steps 92 to * 95 are repeated.

After the above work is completed in step * 96, the basket gripping tool 21 is replaced with the refueling machine 11, the handle 32 is gripped and pulled up vertically to prevent the spent nuclear instrumentation tube 1 from falling off, and then lifted up vertically. .

At step * 97, the basket 27 is leveled and moved to the spent fuel pool 8.

Collectively used nuclear instrumentation tube storage basket 2
FIG. 4 shows an outline of moving 7 to the spent fuel pool 8.

(B) The steps for installing the new nuclear instrumentation tube are shown in FIG.

At step * 101, all the nuclear instrumentation tubes 2 to be replaced are mounted on the nuclear instrumentation tube holders 40 installed in the reactor pressure vessel A.

The nuclear instrumentation pipe holder 40 installed inside the reactor pressure vessel A hung horizontally in step * 102 was moved to the reactor pressure vessel A and caused to wake up, and then the upper lattice plate 3 and the wall of the reactor pressure vessel A were moved. Fixed with a part of.

In step * 103, the illumination 54 inside the reactor pressure vessel A, the television camera 26 inside the reactor pressure vessel A, etc. are installed in the vicinity of the upper lattice plate 3 of the coordinates to be replaced (in order to confirm the installation by the television camera 26, The nuclear instrumentation tube installation guide 19 is not used.)

In step 104, the new nuclear instrumentation tube 2 is grasped by the measuring instrument handling tool 15, and the lever is turned off from above the refueling machine 11 and is turned off from the new nuclear instrumentation tube holding tool 40.

In step 105, the new nuclear instrumentation tube 2 is inserted while checking the television camera 26 in the reactor pressure vessel A.

In step 106, the sheet portion is flushed. (Pedestal work) In step 107, the seating is confirmed by the measuring instrument handling tool 15.

In step 108, the measuring instrument handling tool 15 is disconnected and the process ends.

For the second and subsequent steps, steps * 103 to 108
repeat.

After the completion of all steps of the nuclear instrumentation tube replacement work in step 109, the new nuclear instrumentation tube holder 4 installed inside the reactor pressure vessel A
0 is taken out of the reactor pressure vessel A and decontaminated.

FIG. 5 shows an outline of a method of installing / removing the new nuclear instrumentation tube holder 40 installed inside the reactor pressure vessel A.

As described above, the work steps are simplified by using the two devices.

A schematic diagram of this work is shown in FIG.

According to this embodiment, in the operation of removing the nuclear instrumentation tube in the reactor pressure vessel A, the opening 37 is formed in the side surface of the body so as to be installed in one lattice of the upper lattice plate 3.
, A basket body 28 having a basket body 28, a basket body bottom 29 having a basket installation guide 30 that can be stably installed on the fuel support fitting 6, a fixing hook 39 for fixing on the upper grid plate 3, and a basket movement at the time of moving the basket. A spent nuclear instrumentation tube provided with a moving hook 38 for suspending with a rope and keeping it horizontal, and a handle 32 having a shape that can be handled by the basket gripping tool 21 and having a structure capable of fixing the spent nuclear instrumentation tube 1 to the upper portion of the basket body 28. The use of the storage basket 27 eliminates the work of re-grabbing by the water pressure clamp 16 in the water of the reactor pressure vessel A, and as a result of simplifying the work, a skilled worker becomes unnecessary.

Further, by eliminating the step of moving the spent nuclear instrumentation pipes 1 to the spent fuel pool 8 one by one, it is possible to reduce the time required for the movement and the number of dedicated workers. As shown in FIG. 6, it is sufficient to move the pipes 1 to the spent fuel pool 8 all together at any time after the nuclear instrumentation pipe replacement work and before the fuel loading, which is effective in shortening the process and reducing the incidental work. There is.

When the spent nuclear instrumentation tube storage basket 27 is not used, it can be stored in the spent fuel pool 8 as it is, and therefore the work of taking out and decontaminating can be eliminated.

In the reactor pressure vessel A inner core instrumentation pipe installation work, the reactor pressure vessel A has a slit 49 for straddling the upper lattice plate 3 and has a shape that can be installed on the upper lattice plate 3 near the wall of the reactor pressure vessel A. A holder body bottom 47 having a holder installation guide 48 that can be stably installed on the metal fitting 6,
A holder body 41 that can mount all the new nuclear instrumentation tubes 2 to be replaced on a surface that does not face the reactor pressure vessel A wall, and is fixed to the structure of the reactor pressure vessel A wall to prevent the holder body 41 from falling. In the reactor pressure vessel A, which has a fixing stay 44 that can be attached, and which is equipped with the disconnection lever 42 that can remotely remove the new nuclear instrumentation pipe 2 from the upper part of the fuel refiller 11 and the new nuclear instrumentation pipe 2 and the new nuclear instrumentation pipe 2 Suspend sideways when moving to
By using the new nuclear instrumentation pipe holder 40 installed in the reactor pressure vessel A having the upper hook 50 and the lower hook 51 that are hung straight to be installed on the upper lattice plate 3, the new nuclear instrumentation pipe holder The time for moving and waiting from the dryer / separator pit 10 into the reactor pressure vessel A and the need for a full-time operator are not required, which is effective in reducing the time and incidental work.

When the worker leaves the work site for lunch or after the work is completed, it may be installed in the reactor pressure vessel A,
There is no need to decontaminate each time.

When all the objects to be replaced are removed and then all are mounted as in the conventional case, the television camera in the reactor pressure vessel A and the illumination in the reactor pressure vessel A are installed twice at the same coordinates. By using the two devices at the same time, the illumination lamp 54 in the reactor pressure vessel A and the television camera 26 in the reactor pressure vessel A can be removed and installed at the coordinates, so that the television camera in the reactor pressure vessel A can be attached. The number of steps for moving the illumination inside the reactor pressure vessel A is halved, and when combined with the above effects, work efficiency is significantly improved, and it greatly contributes to the shortening of the critical process, which is currently a major issue of regular inspection work.

The cutting operation of the used nuclear instrumentation tube 1 is not carried out in the reactor pressure vessel A, but is used after the completion of the nuclear instrumentation tube exchange operation in the reactor pressure vessel A until the completion of the regular inspection as shown in FIG. Since it is performed in the spent fuel pool 8, there is no influence on the fuel assemblies in the reactor pressure vessel A, and the process of replacement work is not delayed.

[0121]

According to the invention of claim 1, the used nuclear instrumentation pipes can be easily accommodated from the side without dividing the basket and the plurality of used nuclear instrumentation pipes can be collectively removed after the basket. In comparison with storing spent nuclear instrumentation pipes in a plurality of notches that are separated from each other, it is possible to quickly remove work without leaving cutting waste in the reactor pressure vessel and store it in water. Is easy without requiring skill, the removal work can be performed more quickly, and the work process of the replacement work can be shortened if it is used for the removal work during the replacement work. According to the invention of claim 2, the effect of cutting the used nuclear instrumentation pipe at any time can be obtained.

According to the invention of claim 3, when installing the new nuclear instrumentation tube, the new nuclear instrumentation tube holder and the new nuclear instrumentation tube being transferred at the time of transferring the new nuclear instrumentation tube from the new nuclear instrumentation tube holder. Since it is possible to avoid the interference avoiding operation and rotating the holder each time the new nuclear instrumentation tube is taken out from the holder, the work of installing the new nuclear instrumentation tube can be done quickly without requiring skill,
If used for installation work during replacement work, the work process of replacement work can be shortened.

According to the invention of claim 4, the replacement work of the nuclear instrumentation pipe can promptly remove the used nuclear instrumentation pipe and install the new nuclear instrumentation pipe, so that the whole replacement work process can be shortened. . According to the invention of claim 5, the spent nuclear instrumentation pipes can be easily stored from the side without dividing the spent nuclear instrumentation pipes into the basket, and a plurality of the spent nuclear instrumentation pipes can be collectively removed after the basket. It can be removed quickly without leaving any debris inside, and storage work in water also requires skill compared to storing used nuclear instrumentation tubes in multiple notches that are separated from each other. Therefore, it is possible to provide a transfer and storage means for removing the nuclear instrumentation pipe, which is easy and easy, and can be used for the removal work during the replacement work, which contributes to shortening the work process of the replacement work.

According to the invention of claim 6, in addition to the effect of the invention of claim 5, the posture of the basket body can be stably maintained in the reactor pressure vessel, which contributes to the promotion of the work. According to the invention of claim 7, when installing the new nuclear instrumentation tube, avoiding interference between the new nuclear instrumentation tube holder and the new nuclear instrumentation tube during the transfer when the new nuclear instrumentation tube is transferred from the new nuclear instrumentation tube holder. Since it is possible to avoid rotating the operation and holding tool every time the new nuclear instrumentation tube is taken out from the holding tool, the work of installing the new nuclear instrumentation tube can be done promptly without requiring skill, and the installation work at the time of replacement work When used for, it is possible to provide a means for holding the nuclear instrumentation tube that can contribute to shortening the work process of the replacement work.

According to the invention of claim 8, in addition to the effect of the invention of claim 7, the posture of the holding means of the nuclear instrumentation pipe is maintained stable in the reactor pressure vessel, which can contribute to the promotion of the work.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a work site where a nuclear instrumentation tube replacement work is being performed according to an embodiment of the present invention.

FIG. 2 is a work step diagram of a used nuclear instrumentation tube removal work according to an embodiment of the present invention.

FIG. 3 is a work step diagram of a new nuclear instrumentation tube mounting work according to an embodiment of the present invention.

FIG. 4 is a schematic view of a collective movement of a used nuclear instrumentation tube storage basket according to an embodiment of the present invention.

FIG. 5 is a schematic view of installation / removal of a new nuclear instrumentation tube holder according to an embodiment of the present invention.

FIG. 6 is an explanatory diagram of a movable / cuttable period of a used nuclear instrumentation pipe in a reactor critical process according to an embodiment of the present invention.

FIG. 7 is a perspective view of a used nuclear instrumentation tube storage basket according to an embodiment of the present invention.

FIG. 8 is an external view of a basket gripping tool according to an embodiment of the present invention.

FIG. 9 is a top view of a used nuclear instrumentation tube storage basket according to an embodiment of the present invention.

FIG. 10 is a bottom view of a used nuclear instrumentation tube storage basket according to an embodiment of the present invention.

11 (a) is an external view of the nuclear instrumentation tube dropout prevention mechanism when the used nuclear instrumentation tube storage basket is moved according to an embodiment of the present invention when the handle is pulled up, and FIG. 11 (b) is an illustration of the present invention. FIG. 7 is an external view of the handle of the nuclear instrumentation tube dropout prevention mechanism when the used nuclear instrumentation tube storage basket is moved according to the embodiment.

FIG. 12 is a perspective view of a reactor-installed new nuclear instrumentation tube holder according to an embodiment of the present invention.

FIG. 13 is a bottom view of the in-reactor-type new nuclear instrumentation tube holder according to an embodiment of the present invention.

FIG. 14 is an external view of a separating jig according to an embodiment of the present invention.

FIG. 15 is an elevation view of a nuclear instrumentation tube holding plate according to an embodiment of the present invention.

FIG. 16 is a conventional step diagram for removing used nuclear instrumentation pipes.

FIG. 17 is an enlarged elevation view of the upper and lower ends of the nuclear instrumentation tube.

FIG. 18 is a perspective view of a fuel support fitting.

FIG. 19 is a vertical sectional view of a conventional used nuclear instrumentation tube removal work site.

FIG. 20 is a conventional work step diagram for installing a new nuclear instrumentation tube.

FIG. 21 is a vertical cross-sectional view of a conventional new nuclear instrumentation tube installation work site.

22 is a sectional view taken along line XX of FIG. 7.

23 is a cross-sectional view taken along the line YY of FIG.

FIG. 24 is a perspective view of a rotary drive mechanism of a nuclear instrumentation tube holding plate provided in a reactor-installed new nuclear instrumentation tube holder according to an embodiment of the present invention.

25 is a cross-sectional view taken along the line ZZ of FIG.

[Explanation of symbols]

1 ... spent nuclear instrumentation tube, 2 ... new nuclear instrumentation tube, 3 ... upper lattice plate, 4 ... core support plate, 5 ... lower lattice plate, 6 ... fuel support metal fitting, 7 ... spent fuel pool canal, 8 ... used Used fuel pool, 9 ... Dryer / separator pit canal, 10 ... Dryer / separator pit, 11 ... Fuel changer, 12 ...
Rotating jib crane, 13 ... Fixed auxiliary hoist, 14 ... Auxiliary winding equipment for overhead crane, 15 ... Measuring instrument handling tool, 16 ... Hydraulic clamp, 17 ... Incore manipulator, 18 ... New nuclear instrumentation pipe holder, 19 ... Nuclear instrumentation pipe installation Guide, 20 ... Separation jig, 21 ... Basket gripping tool, 22 ... Gripper tool body, 23 ... Stopper, 24 ... Hose, 25 ... Gripper fitting, 26 ... Reactor TV camera, 27 ... Spent nuclear instrument tube storage Basket, 28 ... Basket body, 29 ... Basket body bottom, 30 ... Basket installation guide, 31 ...
Net, 32 ... Retractable handle, 33 ... Slide rod, 34 ... Rod guide, 35 ... Guide rail, 36 ...
Support, 37 ... Side opening, 38 ... Moving hook, 3
9 ... Fixing hook, 40 ... New nuclear instrumentation tube holder in reactor, 41 ... Holder body, 42 ... Separation lever, 43 ...
Separation lever head, 44 ... Fixing stay, 45 ... Nuclear instrumentation tube holding plate, 46 ... Holding plate fulcrum, 47 ... Holder body bottom part, 48 ... Holder installation guide, 49 ... Slit, 50 ...
Upper hook, 51 ... Lower hook, 52 ... Plunger,
53 ... nose piece, 54 ... furnace lighting, 61-70 ...
Steps to remove the conventional instrumentation tube from the used nuclear reactor,
71-82 ... Conventional new nuclear instrumentation tube installation work step,
91-97 ... Used nuclear instrumentation tube removal work step using the nuclear instrumentation tube storage basket, 101-109 ... New nuclear instrumentation tube attachment work step using the reactor-installed nuclear instrumentation tube holder.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoaki Watabiki 3-2-2, Saiwaicho, Hitachi City, Ibaraki Prefecture Hitachi Engineering Service Co., Ltd.

Claims (8)

[Claims] 1. A basket having an opening extending to the upper end on the side surface thereof is carried into a reactor pressure vessel in which reactor water exists.
Insert the basket into the upper lattice plate in the reactor pressure vessel and set the bottom portion on the fuel support fitting, and then move the spent nuclear instrumentation pipe in the reactor pressure vessel with the fuel changer to move the basket. The plurality of used nuclear instrumentation tubes are stored in the basket by storing the plurality of used nuclear instrumentation tubes in the basket by accommodating them in the basket through the side opening, and then repeating the storage operation. A method of removing the nuclear instrumentation pipes inside the reactor, which moves all of the above together with the pool in the storage location. 2. The basket and the plurality of containers according to claim 1, after the plurality of used nuclear instrumentation tubes are housed in the basket, and at any time before the core confirmation step in the reactor pressure vessel. Of the used nuclear instrumentation pipe, which has been moved together with the used nuclear instrumentation pipe of, into the pool at the storage location, and which has been cut by cutting the used nuclear instrumentation pipe in the pool at any time thereafter. A method for removing the nuclear instrumentation pipes in a nuclear reactor, in which the pipes are stored in the pool. 3. A new nuclear instrumentation pipe holder in which a plurality of new nuclear instrumentation pipes are detachably mounted on one side of the reactor pressure vessel in which reactor water exists is carried into the reactor pressure vessel. , The new nuclear instrumentation tube holder is inserted into the upper lattice plate in the reactor pressure vessel so that the one side faces as much as possible to the installation position of the new nuclear instrumentation tube, and the bottom part is installed on the fuel support metal fitting, A method for installing a nuclear instrumentation pipe in a nuclear reactor, which comprises repeatedly moving the new nuclear instrumentation pipe from the new nuclear instrumentation pipe holder to the installation position with a replacement machine and installing the new nuclear instrumentation pipe at the installation position. 4. The used nuclear instrumentation tube according to claim 3 is used to remove a used nuclear instrumentation tube from the inside of a reactor pressure vessel by the method for removing a nuclear instrumentation tube according to claim 1. A method for replacing a used nuclear instrumentation tube by replacing the used nuclear instrumentation tube with a new nuclear instrumentation tube by installing a new nuclear instrumentation tube according to the installation method. 5. A basket body having a thickness of an external appearance capable of passing through a lattice of an upper lattice plate in a reactor pressure vessel from a lower end to an upper part thereof, and a basket body on a side surface of the basket body. A side opening having a width larger than the thickness of the nuclear instrumentation tube opened from the middle to the upper end, and movably and at least movable in the vertical direction of the basket body on the other side surface of the basket body. A slide rod rotatably mounted on the upper end, a handle rotatably attached to the slide rod, and a slide rod fixedly attached to the slide rod at an angle with the slide rod disposed in the basket body. Storage of used nuclear instrumentation tubes with supports and transfer hooks attached to the sides of the basket body Basket. 6. The basket body according to claim 5, wherein a side surface of the basket body is provided with a fixing hook hooked on an upper lattice plate, and a bottom surface of the basket body is installed in a round hole of a fuel support fitting in a reactor pressure vessel. A storage basket for used nuclear instrumentation pipes, characterized by having a basket installation guide protruding downward. 7. A rotating member between a plurality of recesses provided on one side of a holder body and surrounding a nuclear instrumentation tube, and a position at which a projection adjacent to the recess closes an opening of the recess and a position at which the opening is opened. A freely mounted nuclear instrumentation tube holding plate, a slit provided in the lower part of the holder body for passing an upper lattice plate in the reactor pressure vessel, and a vertically mounted space attached to the holder body. A nuclear instrumentation tube holder with a plurality of hooks. 8. The retainer body according to claim 7, further comprising a fixing stay protruding toward the other side of the retainer body to engage with the reactor pressure vessel. The nuclear instrumentation tube holder characterized in that it is provided with a downwardly projecting holder installation guide which is installed in the round hole of the fuel support fitting.