JP3419252B2 - Method of constructing substructure inside PCV - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is in the technical field of construction of a containment vessel.

[0002]

2. Description of the Related Art Improved boiling water reactor (hereinafter referred to as ABWR
Called. ) In the construction of a plant, a cylindrical R in which a reactor pressure vessel (hereinafter referred to as RPV) is installed.
The PV foundation (hereinafter referred to as the pedestal) is made of a cylindrical steel plate that serves as a concrete pouring formwork inside and outside so that it can support the load of the RPV and withstand vibration sufficiently. In the space sandwiched by each cylindrical steel plate of
It has a structure filled with high-strength concrete, and is divided into several blocks of about 5 steps in the vertical direction,
Each is loaded into the PV and set.

The equipment, pipes, support structures, etc. arranged in the inner space of the steel plate of the inner cylinder of the pedestal have been loaded and set individually before the RPV suspension after the completion of the pedestal construction.

As for the personnel access tunnel (hereinafter referred to as a tunnel), the building side and the pedestal side rise above the height at which the tunnel is set, and the tunnel is above the tunnel when the tunnel can be carried into the set position. Before the setting of the diaphragm floor to be installed at, starts by the lifting machine and is set.

Until the tunnel is completely set up, the tunnel is supported by a temporary mount or the like.

After the tunnel is set up, the inside of the tunnel is painted, and then the site area is handed over to a worker who installs electricity and equipment, and piping, support members, ceiling structural members, etc. are installed.

Most of the pipes (small diameter) in the tunnel are installed densely on the ceiling of the tunnel, and the amount of the material is large.

[0008] The construction of the piping requires scaffold assembly after the area is handed over from the building side, and there is a limit to a large amount of personnel due to the special situation (the working space is narrow) inside the tunnel.

Therefore, a considerable amount of time is required for piping work, which is critical in the process of constructing the containment vessel.

Since the tunnel is the only product / personnel access route leading to the lower part of the dry well (hereinafter referred to as D / W) in the reactor containment vessel, frequent product / personnel access to the D / W. The work inside the access tunnel had to be carried out at different times.

[0011]

As a recent trend of nuclear power plant construction, shortening of construction period is required.

In order to shorten the construction period, it is necessary to shorten the building process on the building construction worker side, which is a critical path, and the RPV and in-furnace work on the equipment installation worker side, which are subcritical.

The work contracted by the former tends to be shortened due to the progress of technology.

Accordingly, RP which is a sub-critical
It has become necessary to shorten V and in-core work concurrently.

At present, the number of personnel is put in and a work system for day and night is used to cope with the shortening process, but this measure is also limited.

As an improved countermeasure, there is a method of bringing in the reactor internal structure in the factory with the RPV installed in advance and carrying it in. However, in this case, even in the present situation, the lifting machine for suspending the RPV is used. Considering that the capacity is full, it is necessary to improve the capacity of the lifting machine for hanging the RPV.

On the other hand, in order to shorten the process without changing the assembly range of the reactor internal structure, it is necessary to carry in the RPV for carrying out the reactor internal work in advance.

In order to carry out this, it is necessary to speed up the construction of the RPV pedestal and its surroundings and cope with the early loading of the RPV.

On the other hand, there is a demand for accelerating the construction of piping for RPV.

The RPV needs to accommodate a myriad of pipes inside the building, and particularly in order to drive and control the control rod drive mechanism (hereinafter referred to as CRD) provided in the lower D / W portion. A large number of small-diameter pipes are used for RPV.

That is, the CRD piping work inside the RPV pedestal and inside the access tunnel is becoming a sub-critical process.

In addition, since many small-diameter pipes are densely packed in the ceiling of these pipes, it takes a lot of labor and steps to complete the work.

On the other hand, in the working environment, concrete is driven into the surrounding area during the construction, resulting in high temperature and high humidity, which is not a good environment.

One of the solutions in such a situation is to make an access tunnel module (with a pipe, a supporting member, a pedestal, etc.).
Since the RPV pedestal and access tunnel are carried in separately, there are many piping joints and the piping module must be a loose module.

Therefore, the number of man-hours for setting work increases,
The advantages of modularization are reduced.

In order to increase the merit of modularization under such conditions, it is important to reduce the work on site for the products (pipes, supporting members, main frame, etc.) that make up the module, Need to be a tighter module.

Therefore, an object of the present invention is to construct a substructure of a reactor containment vessel at an early stage to shorten the construction period of a nuclear power plant including the reactor containment vessel.

[0028]

A first means for achieving the object of the present invention is to provide a member for forming a foundation of a reactor pressure vessel, which is provided around the outer periphery of the foundation, for access to personnel .
The lower part inside the reactor containment vessel
In the method of constructing the tunnel in the part of the foundation
A part of the reactor is attached to form a module,
Install a metal liner on the inner wall of the containment
Attach the other part of the part to the installed metal liner,
Then, hang the module in the installation position.
And carry in the part of the tunnel part to the tunnel part.
Wherein a construction method of the reactor containment vessel lower structure which is characterized in that connected to the other portion, and a portion of the access portion and personnel basis of the reactor pressure vessel tunnel is incorporated hanging installation position simultaneously As a result, the construction of the upper part of the reactor containment vessel, such as the installation of the reactor pressure vessel, can be installed ahead of time, and the construction process of the nuclear power plant can be shortened . Furthermore, that
The action will move the module toward the mounting position
Assemble it into the module as you lower it along the liner
Due to the short length of the part of the tunnel
Built-in tunnel part contacts metal liner
Ru can be suppressed to cause that accident.

Similarly, the second means is to carry in the module.
Previously surrounded by the reactor pressure vessel or the foundation
Inside the internal space, which is in communication with equipment installed in the internal space
And piping arranged in the part of the tunnel portion,
Wherein a construction method of this <br/> and reactor containment vessel bottom structure was characterized by placing equipped with a structural framework that is installed in the inner space, in addition to the effects by the first means, wherein Since the piping, equipment and structural frame in the internal space or tunnel can be brought into the installation location and installed at the same time by suspending the module, piping work, equipment installation work and structural structure installation work can be greatly omitted. The effect of avoiding the time zone when the tunnel is used as an access route to the internal space and eliminating the troublesome work of plumbing inside the tunnel with a bad working environment, further shortening the construction process of the nuclear plant can get.

Similarly, the third means is to carry in the module.
Is a vertical suspension of the module from the suspension balance.
Hanging in flop, a construction method of this <br/> and reactor containment vessel bottom structure was characterized by performing hanging the hanging balance by the crane, in addition to the effects by the first means, the reactor Since the foundation of the pressure vessel and the tunnel are hung vertically with a rope that hangs vertically from the suspension balance, it is not possible to use both the rope and the foundation of the reactor pressure vessel or tunnel as compared with the case where the rope is hung diagonally. It has the effect that it is difficult to add, and when a large and heavy module is hung by attaching a tunnel to the foundation of the reactor pressure vessel, the module can be hung and installed in the installation position without deformation without causing deformation. can get.

Similarly, the fourth means is the inside of the reactor containment vessel.
Of the tunnel portion of the module that has been loaded into
Part is received in a temporary stand installed in the reactor containment vessel in advance.
A method for constructing a lower structure in a reactor containment vessel, characterized in that the module is installed for the first time.
In addition to the effect of the step, the module suspended in the reactor containment vessel receives the tunnel part protruding from the foundation of the reactor pressure vessel on the temporary mount and removes the suspending means at the time of suspension from the tunnel. The effect that the tunnel can be attached to a predetermined partner without deformation is obtained, and the effect that accurate installation work can be performed quickly is obtained.

[0032]

[0033]

[0034]

[0035]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an example of a nuclear power plant, a reactor building 1 shown in FIG. 1 is adopted in a plant of a nuclear power plant.

In the reactor building 1, a reactor containment vessel 25 for housing the reactor pressure vessel 2 is constructed, and a metal liner 3 is installed on the inner wall of the reactor containment vessel 25. There is.

A cylindrical pedestal 4 which is a base for mounting the reactor pressure vessel 2 is installed inside the metal liner 3 to be installed on the inner wall of the reactor containment vessel 25.

The space surrounded by the pedestal 4 and the reactor pressure vessel 2 is a space called a lower dry well 5.

In the lower dry well 5, a control rod drive mechanism 6 which is a device for operating a control rod for controlling the reactor core in the reactor pressure vessel 2 and many other devices are provided. .

A pipe 8 for passing a pressure fluid or an electric wire is connected to these devices.

A structural frame 7 made of steel is constructed in the space inside the lower dry well 5 to support these devices and the support of the pipe 8.

These pipes 8 are passed from the inside of the lower dry well 5 through the tunnel 9 for access to personnel to the inside of the reactor building 1 outside the reactor containment vessel 25.

The tunnel 9 is used as an access route (passage) between the inside of the reactor building 1 and the lower dry well 5.

A diaphragm floor 10 is installed above the tunnel 9.

In such a reactor building 1, unless the tunnel 9 and the pedestal 4 which are the substructures inside the reactor containment vessel 25 are constructed, the upper structure such as the diaphragm floor 10 and the like located above the tunnel 9 and the pedestal 4 are not constructed. It cannot be built, and installation of the reactor pressure vessel 2 on the pedestal 4 will be delayed.

In order to eliminate the factor that delays the construction of such a plant, the following construction method is adopted.

The pedestal 4 is divided into five stages in total, but in this embodiment, considering the load capacity that can be handled by the crane, as shown in FIG. 3, the first stage and the second stage from the bottom are grounded. They are piled up in the assembly yard 13 and integrated by welding or the like.

The pedestal 4 has a double cylindrical structure composed of an inner cylinder 11 made of a steel plate and an outer cylinder 12 made of a steel plate, and the inner cylinder 11 and the outer cylinder 12 are connected by a partition wall made of a steel plate. Are manufactured integrally.

If the crane has the capacity to handle all stages of the pedestal 4 at a stretch, it is ideal for shortening the process to integrate all stages of the pedestal 4 in the ground yard 13.

Between the outer cylinder 12 and the inner cylinder 11 of the pedestal 4, there is incorporated a vent passage 14 for allowing the fluid in the dry well space above the diaphragm floor 10 to pass into the pressure suppression chamber space below the diaphragm floor 10. Has been.

The lower end of the vent channel 14 is constituted by a pipe 15 installed horizontally, and the fluid discharge port is oriented horizontally so as to discharge the fluid horizontally.

As shown in FIG. 3, such a pedestal 4 is erected vertically in an outdoor yard 13 near the construction position of the reactor building 1, and around the pedestal 4, a temporary pedestal 16 is installed. Is placed.

As shown in the upper right side of FIG. 3, a portion of the tunnel 9 made at another place is hung by a crane and carried on the upper part of the temporary mount 16.

The tip of the tunnel 9 is attached to the metal liner 3 at a part thereof, and the divided tunnel 26 is preliminarily attached to the metal liner 3 at a position where the tunnel is attached as shown in FIG. Is attached to.

The carried tunnel 9 is placed on the temporary mount 16 and fixed to the pedestal 4 by welding or the like like the part of the tunnel 9 on the left side of FIG.

The tunnel 9 carried on the temporary mount 16
2, the plurality of pipes 8 are installed in advance on the inner ceiling part via the supports 17 of the pipes 8 as shown in FIG.
It is said to have built in a group of.

Further, below the inside of the tunnel 9, a permanent pedestal 18 is installed as a scaffold for both walking and working.

As described above, the main installation frame 18 and the pipe 8 may be installed in the tunnel 9 in advance before the tunnel 9 is brought into the ground yard 13,
The tunnel 9 may be installed after being attached to the pedestal 4.

When the pipes 8 and the like are installed in advance in the tunnel 9 before the tunnel 9 is brought into the ground yard 13, the work in the ground yard 13 is simplified and the work in the ground yard 13 is simplified. Assembly work in 13 can be done quickly.

Further, as for the pedestal 4, a structural frame 7 made of a steel beam is fixedly installed on the pedestal 4 in a space surrounded by the pedestal 4, and the structural frame 7 supports the pipe 8 as shown in FIG. Pipe 8 supported via
Is installed.

The pipe 8 and the structural frame 7 in the pedestal 4
May be installed before or after fixing the tunnel 9 part and the pedestal 4 part.

Since the pipe 8 installed in the tunnel 9 and the pipe 8 installed in the space surrounded by the pedestal 4 are connected to each other in a large number, both pipes 8 are connected in the ground yard 13. You can leave it.

In this case, after connecting and fixing the tunnel 9 to the pedestal 4, the pipe 8 is connected to the pedestal 4.
The pedestal 4 can be installed at once in the tunnel 9
In comparison with connecting the pipes 8 to the tunnel 9 and the tunnel 9 individually and then connecting the pipes 8 to each other lastly, the work is easy because the work of adjusting the connection position and the angle of the pipe 8 is not required. The installation of 8 can be installed with the main contents for most of the entire length.

When the assembly in the ground yard 13 is completed, the module structure 19 in which the part of the pedestal 4 and the part of the tunnel 9 are integrally assembled is completed.

On the module structure 19, a plurality of suspension fittings on which the wire rope 20 is hooked are dispersed and fixed to the pedestal 4 and the tunnel 9.

The construction of the reactor building 1 is proceeded even while the modular structure 19 is being prepared, and as shown in FIG.
1 is installed on the metal liner 3 installed on the inner wall of the reactor containment vessel 25 and the reactor building 1, and the metal liner 3 installed on the inner wall of the reactor containment vessel 25 can also accommodate the module structure 19. It has been built so much.

When constructing the metal liner 3,
The split tunnel 26 may be attached to the metal liner 3 in advance, and the metal liner 3 attached with the split tunnel 26 may be hung by a crane to be carried into the construction position of the metal liner 3. Alternatively, the split tunnel 26 may be attached to the metal liner 3 and placed after the metal liner 3 is hung by a crane and carried into the construction position of the metal liner 3 and the installation of the metal liner is completed.

Thereafter, the module structure 19 in the ground yard 13 is lifted by the outdoor crane 22 and is hung in the metal liner 3.

The state of the hanging operation is shown in FIG.

The module structure 19 is used for hanging.
Is large and the tunnel 9 protrudes horizontally and is easily collapsed or deformed. Therefore, in order to prevent this, the following hanging method is adopted.

That is, as shown in FIG. 4, the hanging balance 23 is hung from the crane 22, and the wire rope 20 is hung vertically from the hanging balance 23 to form a hanging fitting attached to the pedestal 4 and the tunnel 9. Cross over.

The suspension balance 23 has a cross-shaped planar shape so that the wire rope 20 is vertical.

In this way, the module structure 19 is hoisted by the crane 22. In the suspended state, the wire rope 20 is vertical, so that the wire rope 20 is inclined and a horizontal component force is applied to the module structure 19. There is no phenomenon that occurs, and module structure 1
It is possible to prevent the module structure 19 from collapsing or deforming without applying an unreasonable force to the module 9.

The module structure 19 hoisted by the crane 22 is mounted on the inner wall of the reactor containment vessel 25 by the crane 22 as shown in FIG.
Carried directly above.

Before the carrying operation, the reactor containment vessel 2
A temporary mount 16 for receiving the tunnel 9 without bending is installed at the bottom of the tunnel 5.

The module structure 19 carried directly above the metal liner 3 to be installed on the inner wall of the reactor containment vessel 25.
Is hung by the crane 22 and the reactor containment vessel 25
The pedestal 4 is installed on the bottom of the pedestal, and the tunnel 9 is supported by the temporary mount 16 and connected in series by welding to the split tunnel 26 attached to the metal liner 3 as shown in FIG. It

The hatch 21 can enter and exit the tunnel 9 thus connected.

The reason why the split tunnel 26 is used is that if the tunnel is handled without being split, when the module structure 19 is suspended in the metal liner 3, it is between the inner wall surface of the metal liner 3 and the tip of the tunnel 9. This is to avoid this, as it will cause an interference accident.

The temporary pedestal 16 which supports the tunnel 9 portion of the module structure 19 during the installation is removed to the outside of the reactor building 1 after the installation of the tunnel 9 is completed. .

The module structure 19 is the metal liner 3
When installed inside, the pipe 8 and the structural skeleton 7 and equipment are brought into the space surrounded by the pedestal 4 and the tunnel 9 at the same time. It is possible to significantly reduce the carrying-in work and the construction related to the articles such as, and to promote the construction work above the module structure 19.

Further, the bottom of the reactor containment vessel 25 is located in a deep portion of the reactor building 1, and a large amount of moisture is released from the surrounding concrete or the like during the construction to cause a large amount of moisture, but the moisture is large and narrow. The amount of work in the work environment can be reduced.

After the module structure 19 is installed, the tunnel 9 can be used early as an access route for personnel and equipment to the space surrounded by the pedestal 4, so that the interior of the space, that is, the lower dry well 5 can be used. Work can be promoted.

After installation of the modular structure 19,
As the number of stages above the third stage of the pedestal 4 is built up and concrete is filled between the inner cylinder 11 and the outer cylinder 12 of the pedestal 4, it is possible to install the reactor pressure vessel 2 on the pedestal 4 early. Become.

Further, the construction of the reactor building 1 portion around the metal liner 3 is also advanced.

According to this embodiment, the following effects can be obtained.

According to this embodiment, since the pipe 8 on the ceiling of the tunnel 9 is preset and carried into the tunnel 9,
In addition to labor saving installation work of the pipe 8 in the building,
Since the pipe 8 can be set in the tunnel 9 in a place where the working environment is prepared, the installation accuracy can be improved.

As a result, the construction period of the piping 8 after setting the access tunnel 9 is significantly shortened, and the construction period of the plant construction process of the nuclear power plant can be shortened.

Further, since the amount of work in the reactor building 1 is reduced, the work efficiency is improved and the work period shortening effect is also obtained.

Since the part of the pedestal 4 and the part of the tunnel 9 are integrated and carried in, it becomes possible to access personnel and equipment early after the carry-in, that is, to start the construction in the lower dry well 5. The effect of shortening the construction period can be obtained.

[0090]

According to the present invention, since a portion of the part of the foundation and personnel for access tunnel of the reactor pressure vessel is mounted is incorporated hanging in installed position at the same time, on the construction process of the nuclear plant can be shortened, Modules and atoms
Prevents contact accidents with the metal liner of the reactor containment vessel and reduces safety.
The effect of being complete is obtained.

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a reactor building in a plant of a nuclear power plant.

FIG. 2 is an elevation view showing a module structure of an access tunnel used in an embodiment of the present invention in a partial sectional view.

FIG. 3 is an elevational view with a partial cross-sectional view showing a situation in which a module structure according to an embodiment of the present invention is manufactured in a ground yard.

FIG. 4 is an elevational view with a partial cross-sectional view showing a state in which a module structure according to an embodiment of the present invention is suspended in an installation position.

FIG. 5 is an elevational view with a partial cross-sectional view showing a situation in which the module structure according to the embodiment of the present invention is installed at an installation position.

[Explanation of symbols]

1 ... Reactor building, 2 ... Reactor pressure vessel, 3 ... Metal liner, 4 ... Pedestal, 5 ... Lower dry well, 6 ... Control rod drive mechanism, 7 ... Structural frame, 8 ... Piping, 9 ... Tunnel, 10 ... diaphragm floor, 11 ... inner cylinder, 12 ... outer cylinder, 13 ... ground yard, 14 ... vent passage, 15 ... pipe,
16 ... Temporary mount, 17 ... Support, 18 ... Main mount, 1
9 ... Modular structure, 20 ... Wire rope, 21 ...
Hatch, 22 ... Crane, 23 ... Suspended balance, 25 ... Reactor containment vessel, 26 ... Split tunnel.

Front Page Continuation (72) Koichi Gota, 1-1 1-1 Sachimachi, Hitachi City, Ibaraki Hitachi Ltd. Hitachi factory, Hitachi (72) 3-1-1, Koichi Murayama, Inventor, Koichi Murayama, Hitachi City, Ibaraki Prefecture Stock company Hitachi Ltd. In Hitachi factory (56) Reference JP-A-4-128694 (JP, A) JP-A-9-113667 (JP, A) JP-A-60-100793 (JP, A) JP-A-64- 75749 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G21C 13/00 G21C 13/024

Claims (6)

(57) [Claims] 1. A tunnel for access to personnel, which is provided on a member constituting a foundation of a reactor pressure vessel and is provided around an outer periphery of the foundation.
Parts to build the substructure inside the reactor containment vessel.
In the method of
Parts to form a module, and
Install a metal liner on the inner wall of the vessel and
Parts to the installed metal liner, then
Bring the module into the installation position by hanging it
The part of the tunnel part and the part of the tunnel part
A method for constructing a lower structure in a containment vessel characterized by connecting to another part . 2. A member forming the basis of a reactor pressure vessel
Tunnel for access to personnel deployed around the outside of the foundation
Parts to build the substructure inside the reactor containment vessel.
In the method of
Parts to form a module,
Bring in the metal liner with other parts attached to the construction position,
Then, hang the module in the installation position.
And carry in the part of the tunnel part to the tunnel part.
A method for constructing a lower structure in a reactor containment vessel, which is characterized in that it is connected to another part . 3. A member forming a foundation of a reactor pressure vessel.
Tunnel for access to personnel deployed around the outside of the foundation
Parts to build the substructure inside the reactor containment vessel.
In the method of
Parts to form a module,
Install the metal liner with the other parts attached, and then
Carry the module into the installation position by hanging it.
Connect the part of the tunnel part to another part of the tunnel part.
A method for constructing a substructure inside a containment vessel characterized by being continued . 4. The odor according to any one of claims 1 to 3.
Prior to loading the module, the reactor pressure vessel or
Is for equipment installed in the internal space surrounded by the foundation
The inside of the internal space and the one of the tunnel portions are communicated with each other.
Piping installed inside the unit and the structure installed in the internal space
A method for constructing a lower structure in a nuclear reactor containment vessel, characterized by being equipped with a structure. 5. The odor according to any one of claims 1 to 4.
When loading the module, suspend the module from the ceiling.
Suspend with a rope that hangs vertically from the scale and lift the suspension balance.
A method for constructing a lower structure inside a containment vessel characterized by being hung by a heavy machine . 6. The odor according to any one of claims 1 to 5.
The module loaded in the reactor containment vessel
The part of the tunnel part of the reactor containment vessel
Install the module by receiving it on the temporary frame installed inside
A method for constructing a lower structure in a reactor containment vessel, which is characterized by carrying out a mortar .