JPH06230175A - Fuel and internal pump replacing machine for nuclear reactor - Google Patents

Abstract

PURPOSE:To provide a fuel and internal pump replacing machine in which the degree of freedom is ensured in the structure of an internal pump replacing unit while ensuring aseismic strength and rigid safety structure easily, and the time and manpower required for maintenance of the internal pump replacing unit are reduced while reducing the exposure to radiation. CONSTITUTION:A running truck 41 has a self-running means and constituted to allow the traverse of a traversing truck 27 mounting a fuel replacing mast 28. A running truck 42 has a powerless truck equipped with no self-running means, loaded with a nonexciting brake unit 45, and coupled with the running truck 41 through a coupling unit 44. Noncontact data transmission units 46A, 46B are disposed on the opposing side face parts of the running trucks 41, 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiling water nuclear reactor equipped with an internal pump, for example, to replace the fuel in the reactor and to use the fuel and the internal fuel for the reactor. It relates to a pump changer.

[0002]

2. Description of the Related Art Conventionally, in a general boiling water reactor, a jet pump is housed in a reactor pressure vessel and a part of the reactor water is taken out of the reactor pressure vessel. A method has been adopted in which the reactor water is pressurized by a recirculation pump, sent as drive water to a jet pump, and the reactor water in the core is circulated by the jet pump.

However, this method is not only structurally considerably complicated, but also has a problem that it is not preferable because the pipe connecting the jet pump and the recirculation pump is arranged outside the reactor. It was

Therefore, in recent years, a boiling water reactor equipped with an internal pump as shown in FIGS. 4 and 5 has been developed as a recirculation pump provided in the nuclear reactor to omit piping. ing.

In this type of boiling water nuclear reactor, as shown in FIG. 4, a shroud 2 is provided in a reactor pressure vessel 1, and a reactor core 3 is housed in the shroud 2 to form a reactor pressure vessel 1.
There are multiple internal pumps 4 (eg 10) at the bottom of the
It is arranged.

However, the reactor water in the reactor pressure vessel 1 is
It descends in the downcomer 5 formed between the outer peripheral surface of the shroud 2 and the inner peripheral surface of the reactor pressure vessel 1, and is sent to the lower side of the core 3 via the internal pump 4, and from this lower side to the inside of the core 3 It is supposed to flow into. The reactor water that has flowed into the core 3 boils due to the heat generated by the nuclear reaction, flows upward as a two-phase flow of water and steam, and flows through the steam-water separator 6 disposed above the core 3. Through which it is separated into water and steam. The separated steam is sent to a turbine (not shown) or the like after the moisture is removed by the steam dryer 7, while the separated water is supplied through the internal pump 4 together with the water supply supplied from the water supply sparger 8. And sent again into the core 3.

On the other hand, for example, about 200 control rods (not shown) and about 800 fuel rods (not shown) are inserted in the core 3 of the reactor pressure vessel 1, and the control rods drive the control rods. A nuclear reaction in the core 3 is controlled by being inserted into or extracted from the core 3 via an apparatus (not shown).

Further, the internal pump 4 is a pump portion having a diffuser 9 and an impeller 10 as shown in FIG.
Equipped with 11. The diffuser 9 is pressed onto the pump nozzle 14 of the reactor pressure vessel 1 via the stretch tube 12 and the stretch tube nut 13 and is connected to the motor casing 15 inserted into the pump nozzle 14 from below. .

A water immersion type motor 16 is housed in the motor casing 15, and a motor cover is attached to the lower end of the motor 16.
17 is installed. The motor cover 17 is arranged in close contact with the lower surface of the motor casing 15 and has a nut 19 screwed into the stud bolt 18 for mounting the motor cover 15 thereon.
The motor 16 is fixed in the motor casing 15 while being kept watertight. This motor 16 and impeller 10
Are connected to each other via a shaft 20, and the impeller 10 is driven via the shaft 20.

The internal pump 4 having the above structure
As with ordinary equipment, it is necessary to periodically disassemble and remove the components, and then inspect and repair the removed components at another location outside the containment vessel.

By the way, the procedure for disassembling the internal pump 4 and removing the components is as follows.
, The nut 19 is removed, and the motor 16 is pulled downward from the motor casing 15. Impeller 10 in this state
Then, the shaft 20 is pulled out upward, both the impeller 10 and the shaft 20 are integrally removed, and then the stretch tube nut 13 is removed and pulled out together with the diffuser 9.

[0012] The impeller of the pump unit 11 removed
10 and shaft 20, diffuser 9 and stretch tube 12
The carry-in / out port A or B formed in the top guide 25 shown in FIG. 4 through the space above the annular downcomer 5 formed by the inner peripheral surface of the reactor pressure vessel 1 and the outer peripheral surface of the shroud 2 (see FIG. 5)) to the reactor pressure vessel 1
It is carried out.

The motor 16 removed from the internal pump 4 passes through the pedestal supporting the reactor pressure vessel 1 and is carried out from an equipment carry-in / out port formed in the pedestal through another device (not shown). . Further, the assembly and mounting of the internal pump 4 are performed in the reverse order of the above.

By the way, on the inner peripheral wall surface of the reactor pressure vessel 1, as shown in FIG. 7, a large number of projecting portions such as the feed water sparger 8, the low pressure water injection sparger 22, the core spray pipe 23 and the like are attached. Further, a disk-shaped top guide 25 is housed around the upper lattice plate 24 of the cylindrical shroud 2 in proximity to the inner peripheral wall of the reactor pressure vessel 1. For this reason,
At present, the annular space formed by these elements has a very small margin, and moreover, the impeller of the pump section 11 is
10 and shaft 20, diffuser 9 and stretch tube 12
Generally, it is quite large and heavy.

Since the internal pump 4 is housed in the bottom of the reactor pressure vessel 1 and is always in the reactor water, the pump portion 11 is removed from the pump nozzle 14 and carried out of the reactor pressure vessel 1. The replacement work including the work to carry out and the work to carry the pump unit 11 into the reactor pressure vessel 1 and attach it to the pump nozzle 14 is extremely troublesome.

Therefore, as shown in FIG. 8, a fuel changer is generally used to replace the pump portion 11 of the internal pump 4. That is, the refueling machine travels on a traveling rail 33 laid on the refueling floor 32 over the reactor pressure vessel (not shown) and across the reactor pressure vessel as shown in FIG. Possible traveling carriage 26, traveling carriage 27 provided so as to be able to traverse on this traveling carriage 26, fuel replacement mast 28 provided on this traveling carriage 27, and internal pump replacement device 21. The internal pump replacement device 21 is equipped with a hoist (not shown), and the downcomer 5 to the internal pump 4 at the deep bottom part has a grip 29 and a TV camera 30. It is possible to replace the pump portion 11 of the internal pump 4 by hanging down. The operation of the refueling machine is performed via the operation panel 35 installed in the remote operation room 34, but a monitor 36, a television camera 37, etc. are used.

[0017]

By the way, the internal pump replacement device 21 has a built-in hoist for hoisting the wire rope. However, as shown in FIG. Since the wire rope 31 is hung down to the deepest part of the container 1, the extension length of the wire rope 31 is considerably longer than the size of the internal pump replacement device 21. Also, the wire rope 31, the internal pump replacement parts to be lifted up, that is, the impeller 10, the shaft 20, the diffuser 9, and the stretch tube 12 are quite large and heavy, and they do not fall due to an earthquake or the like. Therefore, a large cross section, that is, a thick one is used. Therefore, the hoist around which the wire rope 31 is wound is structurally strong and has a considerable weight.

On the other hand, since the refueling machine is located above the reactor pressure vessel 1, if a drop accident occurs due to damage of parts due to an earthquake or the like, it may cause serious troubles in the reactor structure. There is. Therefore, sufficient strength and safety must be ensured for all cases.

The refueling machine is originally installed for the purpose of refueling, and has sufficient strength and safety. However, if the internal pump replacement device is added as described above, the internal pump is replaced. Since the weight of the replacement device is considerably large, the conventional structure cannot secure sufficient strength.

Therefore, this problem can be solved by improving the structure of the refueling machine to a strong one, but in the current situation where the weight of the internal pump 4 is increasing, it is extremely difficult. is there. Further, the internal pump replacement device is, as shown in FIG.
Since it operates with a telescopic arm that swings around an axis that matches the center axis of the fuel refueling machine, it must be located exactly in the center of the refueling machine. The structure of the refueling machine is disadvantageous.

Now, in order to explain the problem of the seismic strength of the refueling machine, consider one simple model. Figure 9
At the midpoint of the beam 60 that simulates the traveling carriage 26, at the mass point 61 that simulates the traverse carriage 27 and the internal pump replacement device 21.
This is a model with (m ₁ ). In this model,
Given that the mass of the beam 60 itself is m ₂ , the natural frequency of this model is approximately represented by √k / (m ₁ + 0.49m ₂ ). Here, k is a constant indicating the rigidity of the beam 60.

As is clear from this equation, it can be seen that as the mass m ₂ of the mass point 61 increases, the natural frequency decreases and the seismic strength decreases. Beam 60 corresponding to the increase in m ₁
If the rigidity k of the beam 60 is increased, it is possible to suppress a decrease in the natural frequency, but in reality, increasing the rigidity k of the beam 60 also increases the mass m ₂ of the beam 60 itself.
As a result, the reality is that most of the problems cannot be solved.

On the other hand, the internal pump replacement device 21 is
As described above, it incorporates a considerably large winding device for winding a long wire rope, and a drive device for rotating a heavy arm protruding further long.
Since a more stable support method is required from the viewpoint of earthquake resistance, a considerably large space is required.

However, as shown in FIG. 8, the peripheral structure of the internal pump replacement device is often restricted because it is close to the passage area of the transverse carriage 27. If a large space is to be secured, the outer shape of the refueling machine itself becomes enormous, so that the overall mass increases and it becomes impossible to secure the seismic strength as described above. As such, internal pump replacement devices must be constructed with compelling choices under fairly constrained conditions.

Further, since the internal pump replacement device must be arranged below the traveling area of the transverse carriage 27,
Maintenance of each part of the hoisting mechanism and the turning drive mechanism inside thereof is difficult. This leads to an increase in the working time of the worker who performs maintenance, which causes a problem of increasing the amount of radiation exposure to the worker.

Therefore, an object of the present invention is to easily secure seismic resistance, to secure a degree of freedom in constructing an internal pump replacement device while obtaining a safe and strong structure, and to provide an internal pump replacement device. An object of the present invention is to provide a fuel and internal pump changer for a nuclear reactor, which facilitates maintenance, reduces time and labor required, and reduces exposure dose.

[0027]

In order to achieve the above object, the present invention provides a traveling carriage provided above a reactor pressure vessel so as to be capable of traveling across the reactor pressure vessel, and a traveling carriage on the traveling carriage. A traversing carriage that can traverse and an internal pump that replaces the internal pump unit arranged at the bottom of the reactor pressure vessel by operating the grips that are hung from the traverse carriage into the reactor pressure vessel A fuel and internal pump changer for a reactor, which is equipped with a change device and a fuel change mast for changing fuel, and is operated remotely from a remote control room. The present invention is characterized by comprising a traveling carriage for replacement and a traveling carriage for exclusive use of internal pump replacement equipped with an internal pump replacement device.

[0028]

[Operation] With the above configuration, the seismic resistance of the internal pump replacement traveling vehicle equipped with the internal pump replacement device can be reliably obtained by a relatively easy method, and the internal pump replacement can be performed. A wide space around the device can be secured, the maintenance of the internal pump replacement device is easy and the exposure dose can be reduced, while the refueling trolley equipped with the refueling mast is also more earthquake-resistant than before. Can be secured.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of the present invention,
In the figure, reference numeral 40 denotes a reactor fuel and internal pump changer, which is composed of a traveling carriage 41 and a traveling carriage 42. In the traveling carriage 42, the internal pump replacement device 21 is mounted near the center of the carriage, and the inspection cover 43 is detachably provided on the upper portion of the traveling carriage 41.
The traverse trolley 27 equipped with can be traversed,
It is equipped with self-propelled driving means.

The traveling carriage 42 has an unpowered carriage having no means for traveling by itself, and can travel on a set of traveling rails 33 common to the traveling carriage 41.
If the two are connected via 44, the traveling carriage 41 equipped with a self-propelled means can perform tow traveling.

The connecting device 44 includes a traveling carriage 41 to a traveling carriage 42.
It is also configured so that a power source can be connected to.
Therefore, after connecting both traveling carriages 41 and 42,
Side, power is connected to the traveling carriage 42 and power is supplied,
The internal pump replacement device 21 is adapted to be driven.

A non-excitation operation type braking device 45 is mounted on the traveling carriage 42. When the inside of the traveling vehicle 42 is in the power-off state, that is, in the non-pulling state (free state), the brake device 45 can operate to maintain the stopped state, and the connecting device 44 is connected to the brake device 45.
When the power supply is connected to and excited, the stop state is released,
It is possible to drive together.

On the other hand, data transmission devices 46A and 46B of a non-contact (for example, wireless type) data transmission system are arranged on the respective side surfaces of the traveling carriages 41 and 42 which face each other, and the internal pumps are provided. An electric signal for monitoring or controlling the replacement work of the replacement device 21 can be transmitted to the traveling carriage 41. The transmitted electric signal is sent to a control panel (not shown). The data transmission device 46
Instead of arranging A and 46B, a signal transmission means may be built in the coupling device 44 to transmit data.

Further, the traveling carriages 41, 42 are provided with obstacle detection sensors 47, 47, respectively, and the traveling rail 33
In addition to being able to detect obstacles in the vicinity, collisions are also prevented by detecting the approach of the traveling carriages 41, 42 to each other. In the figure, 29 is a grip, 30 is a television camera with a zoom lens, and 31 is a wire rope.

In the embodiment having the above structure (hereinafter, referred to as the first embodiment), in consideration of the seismic resistance of the traveling carriage 42, the weight of the internal pump replacement device 21 is generally the weight of the traverse carriage 27. Since the traveling carriage 42 is lighter than the above, and no heavy object such as this is mounted on the traveling carriage 42 except the internal pump replacement device 21 is exclusively mounted, it is possible to easily ensure the earthquake-proof strength of the traveling carriage 42. On the other hand, since the traveling carriage 41 is also not equipped with the internal pump replacement device 21, its seismic resistance is improved.

Further, the traveling carriage 42 has a structure in which there is no obstacle for restraining the internal pump replacement device 21 in the vicinity thereof, a large free space can be secured, and seismic strength is easily obtained. As a result, it is possible to easily increase the capacity and seismic performance of the internal pump replacement device 21 itself. In addition, the maintenance and inspection work of each part of the internal pump replacement device 21 is significantly easier than the conventional one.

On the other hand, the traveling carriage 42 is unpowered and cannot travel by itself, but if it is towed, the connecting device is
Even if 44 is broken and released, the non-excitation operation type braking device 45 automatically operates and stops, so that safety can be ensured.

When carrying out refueling work, the traveling carriage 42
However, the collision with the traveling carriage 42 can be prevented by the operation of the obstacle detection sensor 47. On the other hand, the internal pump replacement work has a lower frequency than the fuel replacement work, and therefore the traveling is usually performed by the traveling carriage 41 alone. Therefore, the weight of the traveling carriage 41 is lightened, so that energy is saved and an efficient fuel changer is provided. The present invention is not limited to the above-described first embodiment, and various modifications can be made.

FIG. 2 shows another embodiment of the present invention (hereinafter referred to as the second embodiment).
FIG. 3 is a front view showing the embodiment). In FIG. 2 and FIG. 3, 50 is a reactor fuel and internal pump changer, which is a traveling carriage 51 and a traveling carriage 52.
It is composed of. The traveling carriage 52 is equipped with the internal pump replacement device 21 near the center of the carriage, the inspection cover 43 is detachably provided on the upper portion, and the traveling carriage 51 is provided with the refueling mast 28 as in the conventional case. The trolley 27 can be traversed.

The traveling vehicle 52 is an unpowered vehicle that has no means for traveling by itself, and the traveling rail on which the other traveling vehicle 51 travels.
A special traveling rail 54 laid parallel to the inside of 53 is run. The traveling carriage 52 is a traveling carriage.
The height is lower than that of 51, and as shown in FIG. 3, it is possible to pass through the lower side of the traveling vehicle 51 without interference.

A connecting device 55A and a connecting device 55B are attached to the lower surface of the traveling carriage 51 and the upper surface of the traveling carriage 52, and the positional relationship in which the traveling carriage 52 is hung under the traveling carriage 51 as shown in FIG. The vehicle is connected by a connecting member and can be towed by a traveling carriage 51 equipped with a self-propelled traveling means.

The connecting devices 55A and 55B are so constructed that power can be connected from the traveling carriage 51 to the traveling carriage 52. After connecting both traveling carriages 51 and 52, traveling carriage 51
Side, power is connected to the traveling carriage 52 and power is supplied,
The internal pump replacement device 21 is adapted to be driven.

Further, the traveling vehicle 52 is provided with a non-excitation operation type brake device 56. When the inside of the traveling vehicle 52 is in the power-off state, that is, in the non-pulling state (free state), the brake device 56 can operate to maintain the stopped state, the coupling devices 55A and 55B are coupled, and the braking device 56 When the power source is connected to and is excited, the stopped state is released and it is possible to travel integrally.

On the other hand, data transmission devices 46A and 46B of a non-contact (for example, wireless) type for transmitting data are provided on the lower and upper surfaces of the traveling vehicles 51 and 52, respectively, which face each other. , An electric signal for monitoring or controlling the replacement work of the internal pump replacement device 21,
Can be transmitted to. The transmitted electric signal is sent to a control panel (not shown). Instead of disposing the data transmission devices 46A and 46B, the connection devices 55A and 55B may be provided with signal transmission means to transmit data.

In the second embodiment having the above-mentioned structure, the seismic resistance of both traveling carriages 51 and 52 can be easily ensured in the same manner as the above-mentioned embodiment, and the capacity of the internal pump replacement device 21 itself and the seismic performance can be improved. It's also easy to upgrade. In addition, since the space around the internal pump replacement device 21 can be relatively wide and arbitrarily secured, the degree of freedom in the configuration is increased, and the maintenance and inspection work of each part is significantly easier than in the conventional case.

On the other hand, the traveling vehicle 52 is unpowered and cannot travel by itself, but as in the first embodiment described above, the coupling devices 55A and 55B are broken and released during the towing traveling. Even if there is, safety can be ensured because the non-excitation operation type braking device 56 automatically operates and stops.

When carrying out refueling work, the traveling carriage 52
However, since the traveling carriage 51 and the traveling carriage 51 can pass each other,
You can drive safely without fear of collision. On the other hand, since the internal pump replacement work is less frequent than the fuel replacement work, the traveling trolley 51 is usually the main unit for traveling. Therefore, the weight of the traveling carriage 51 is reduced, so that energy is saved and the fuel refilling machine becomes efficient.

Further, both traveling carriages 51, 52 can greatly increase the seismic resistance as compared with the conventional one, and can be stored in a space which does not change much compared with the conventional one except for adding one set of traveling rails 54. .

In the first embodiment described above, the traveling carriage is
It was impossible to drive 42 without power, but this traveling trolley
42 may also be equipped with a set of self-driving means similar to the traveling carriage 41 (including connection to a power supply) so that both traveling carriages can travel independently on one set of rails. in this case,
In order to prevent both traveling vehicles from colliding with each other, the control system is configured so that both traveling vehicles do not drive by themselves at the same time, while an abnormal approach of both traveling vehicles is detected by an obstacle detection sensor (shown as 47 in Fig. 1). To prevent collisions.
When one of the traveling vehicles is operating, the other traveling vehicle is retreated to the standby position. With such a configuration, the coupling device 44 and the data transmission device 46 in the first embodiment.
A and 46B are unnecessary. Also in the third embodiment configured as described above, the same effect as that of each of the above-described embodiments can be obtained.

In the second embodiment described above, the traveling carriage is
It was impossible to drive 52 without power, but this traveling trolley
52 is also equipped with a set of self-driving means (including the connection to the power supply) similar to the traveling carriage 51, and it travels on its own on a dedicated traveling rail 54 laid parallel to the inside of the traveling rail 53 of the traveling carriage 51. It can be so. Of course, a traveling vehicle equipped with a set of self-propelled traveling means is also configured to be able to pass through the lower side of another traveling vehicle 51 without interference. With such a configuration, the connection devices 55A and 55B and the data transmission devices 46A and 46B in the second embodiment are unnecessary. Also in the fourth embodiment configured as described above, the same effects as in the above-described respective embodiments can be obtained.

[0051]

As described above, according to the present invention, the traveling carriage provided above the reactor pressure vessel so as to be capable of traveling across the reactor pressure vessel, and the traveling carriage can be traversed. And an internal pump replacement device for operating the traverse carriage and a gripping tool that is suspended from the traverse carriage into the reactor pressure vessel to replace the internal pump portion arranged at the bottom of the reactor pressure vessel. A fuel and internal pump changer for a nuclear reactor that is equipped with a fuel change mast that changes fuel, and is operated remotely from a remote control room. Since it consists of a dolly and an internal pump replacement trolley equipped with an internal pump replacement device, it provides a reactor fuel and internal pump replacement machine with the following effects. Kill.

(1) The internal pump replacement device can be installed with a large seismic resistance, and the load on the fuel refueling machine, which is the mother body, is reduced. Can be improved.

(2) Since a space around the internal pump replacement device can be secured, a structure with a high degree of freedom can be obtained,
This enables an efficient configuration and improves the seismic performance of the internal pump replacement device itself.

(3) Since the maintenance of the internal pump replacement device becomes easy and the required work time is shortened,
The radiation dose to workers is reduced, and it is safe and easy to handle.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing another embodiment of the present invention.

FIG. 3 is a front view of another embodiment of the present invention.

FIG. 4 is a sectional view showing a nuclear reactor equipped with an internal pump.

5 is a sectional view taken along line CC of FIG.

FIG. 6 is a vertical cross-sectional view of an internal pump.

FIG. 7 is an explanatory diagram showing an outline of internal pump replacement work.

FIG. 8 is a perspective view showing an outline of a conventional fuel and internal pump changer for a nuclear reactor.

FIG. 9 is a simplified vibration model diagram of the refueling machine.

[Explanation of symbols]

1 ... Reactor pressure vessel, 3 ... Reactor core, 4 ... Internal pump, 10 ... Impeller, 11 ... Pump section, 16 ... Water immersion type motor,
20 ... Shaft, 21 ... Internal pump replacement device, 27 ... Traverse carriage, 28 ... Fuel replacement mast, 29 ... Grip, 31 ... Wire rope, 34 ... Remote control room, 35 ... Control panel, 41, 42, 51, 52 ...
Traveling vehicle, 44, 55A, 55B ... Coupling device, 45, 56 ... Non-excitation operation type brake device, 46A, 46B ... Data transmission device, 47
… Obstacle detection sensor.

Claims (5)

[Claims] 1. A traveling carriage provided above the reactor pressure vessel so as to be capable of traveling across the reactor pressure vessel, a traverse carriage capable of traversing the traveling carriage, and the reactor from the traverse carriage. A fuel replacement mast for exchanging fuel with an internal pump replacement device for replacing an internal pump portion arranged at the bottom of the reactor pressure container by operating a grasping tool that is suspended in the pressure container. In a fuel and internal pump changer of a nuclear reactor which is remotely controlled from a remote control room, a traveling vehicle for refueling equipped with the traverse carriage for refueling, and the internal pump exchange A fuel and internal pump replacement machine for a nuclear reactor, comprising a traveling vehicle for internal pump replacement, which is equipped with a replacement device. 2. The reactor fuel and internal pump changer according to claim 1, wherein both traveling carriages travel while sharing a set of rails, and one of the traveling carriages is used. Equipped with a drive source for traveling on a traveling vehicle,
One set or a plurality of connecting devices are arranged on the two traveling carriages, the traveling carriages are connected to each other according to the contents of the replacement work, and the towing traveling by the traveling carriage on one drive side or the connection is performed. A fuel and internal pump changer for a nuclear reactor, characterized in that it is released to perform independent traveling to perform internal pump replacement work and fuel replacement work. 3. The fuel and internal pump changer for a nuclear reactor according to claim 1, wherein both traveling carriages run on separate rails independently and in parallel vertically.
A drive source for traveling to one of the two traveling carriages is mounted so that they do not interfere with each other, and one set or a plurality of coupling devices are arranged on the traveling carriages. According to the content of the replacement work, the two traveling carriages are connected to each other, and the traveling carriage on one drive side pulls or releases the connection to carry out the independent traveling to perform the internal pump replacement work. A fuel and internal pump changer for a nuclear reactor, which is characterized by performing a fuel change operation. 4. The fuel and internal pump changer for a nuclear reactor according to claim 1, wherein both traveling carriages travel while sharing one set of rails, and both traveling carriages independently travel independently. Reactor fuel and internal pump removal, characterized by carrying out independent traveling of the traveling carriage corresponding to the content of the replacement work to perform internal pump replacement work and fuel replacement work. Replacement machine. 5. The fuel and internal pump changer for a nuclear reactor according to claim 1, wherein both traveling carriages independently travel on separate rails and run in parallel vertically.
Configured so that they do not pass each other and interfere with each other, both of the traveling carriages have a function of independently traveling independently, and the traveling carriages perform independent traveling corresponding to the content of the replacement work, and internal pump replacement work and fuel A fuel and internal pump replacement machine for a nuclear reactor, which is characterized by performing replacement work.