JPH1123770A - Reactor building and lay-down method on refueling floor in the building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lay down an article including a well cover by using a large piece bring-in opening by placing beams, walls, etc., around the large piece bring-in opening and structuring so as to support the weight of articles including a reactor well cover. SOLUTION: By placing beams around a large piece bring-in opening 6 so as to support a reactor well cover 7, etc., it is made possible to lay down the cover 7 at the opening 6. By structuring so as to lay down the well cover 7 around the entrance 6 so that the upper surface of the cover 7 and the floor level of the refueling floor 2 are the same level, accessibility of the entrance is improved. Thus, by setting the opening 6 as a lay down space and laying down the cover 7 using a part of or whole opening, the space for laying down apparatus and equipments on the refueling floor 2 and working for inspection can be widely ensured and the shortening inspection period due to the improvement of the inspection work efficiency or reducing the size of the building is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a reactor building and a method of laying down a refueling floor in the building.

[0002]

2. Description of the Related Art FIG. 3 shows a lay-down situation when a refueling floor of a conventional reactor building is inspected.

[0003] In the reactor building 1, maintenance and inspection work (hereinafter referred to as "inspection") that is regularly performed every year to confirm that there is no functional problem with equipment and the like is performed. The laydown situation at the time of the inspection of the refueling floor 2 in the furnace building 1 is as follows.

[0004] Large equipment such as a nuclear reactor is arranged in the reactor building 1. At the time of annual inspection, these devices are disassembled and restored using an overhead crane installed on the refueling floor 2.

Generally, a refueling floor 2 is provided above the reactor building 1, and a reactor well 3 is provided in the center of the refueling floor 2, which is an upper space of the reactor. A spent fuel pool 4 and an equipment temporary storage pool 5 are provided on both sides of the reactor well 3.

Further, a floor opening (hereinafter, referred to as a large cargo entrance) 6 is provided on the refueling floor 2 for carrying in / out materials and tools for inspection and for carrying in / out of replacement parts. is there.

Reactor well 3, spent fuel pool 4,
The fuel replacement floor around the equipment temporary storage pool 5, the large cargo entrance 6, etc. is used as a space for laying down equipment and facilities when the reactor is opened for refueling work of the reactor during inspection. .

On the other hand, in recent years, there has been a tendency to reduce the volume of the building mainly from the viewpoint of economy, but the dimensions of the building above the refueling floor 2 of the reactor building 1 are limited to the above-mentioned equipment and facilities. The floor area required for laydown is a constraint.

Means for securing a large area for the fuel replacement floor is disclosed in Japanese Patent Publication No. Sho 63-215998, "Installation Structure of Tanks". Here, tanks provided on the fuel replacement floor are provided below the fuel replacement floor. This prior art does not disclose the effective use of the large cargo entrance.

[0010]

The conventional method of laying down the refueling floor 2 of the reactor building 1 has the following problems.

In the conventional reactor building 1, when equipment and facilities are laid down to the fuel replacement floor 2, the equipment and facilities are replaced with the reactor well 3, the spent fuel pool 4, the equipment temporary pool 5,
Lay down to a space avoiding the large cargo entrance 6 etc. For example, since the reactor well cover 7 is temporarily placed in the space shown in FIG. 2, the degree of freedom of the laydown of the operation floor is limited, which causes deterioration of work efficiency and an increase in inspection period.

In recent years, mainly from the viewpoint of economy, there has been a demand for a reduction in a building volume and a reduction in an inspection period by improving an inspection work efficiency.

As described above, in order to lay down the equipment and facilities on the refueling floor 2 and perform inspection work on those equipment and facilities, a space for equipment equipment laydown and inspection work space are required. The plane dimensions and area of the floor 2 are restricted.

Here, in order to shorten the inspection period by improving the efficiency of the laydown work at the time of the inspection, the equipment and the like to be laid down are reduced in size, or the reactor building 1 is enlarged and the refueling It is necessary to increase the area or to secure a wider laydown space in the refueling bed 2 in the same space as the conventional one.

Here, in order to secure a wider laydown space in the refueling bed 2 in the same space as the conventional refueling bed 2, the large cargo entrance 6 is set as a laydown space and the equipment and facilities are laid down. However, since the structure around the large cargo entrance 6 is not a structure capable of supporting the equipment and facilities, the equipment and facilities cannot be laid down to the large cargo entrance.

Further, when the equipment and facilities are laid down to the large-size carry-in entrance 6, articles cannot be carried in and out of the large-size carry-in entrance 6, and the function of the large-size carry-in entrance 6 cannot be provided. It was not possible to lay down to the big cargo entrance 6.

An object of the present invention is to provide a large cargo entrance 6 when equipment and facilities are temporarily placed on the refueling floor 2 during inspection of the reactor building 1.
By laying down the reactor well cover 7
The reactor building 1 and the refueling floor 2 in the building can increase the degree of freedom of laydown and reduce the inspection period by improving the work efficiency or reduce the amount of construction by reducing the size of the building. It is to provide a laydown method.

[0018]

The above object can be achieved as follows.

(1) A reactor building provided with a loading / unloading port for articles provided on the refueling floor, wherein the structure around the loading / unloading port has a structure capable of supporting the load of articles including a reactor well cover laid down. .

(2) An article including a reactor well cover is covered by a method of laying down articles on a refueling floor in a reactor building by partially or entirely covering an article loading / unloading port provided on the refueling floor. Lay down to the refueling floor.

(3) In (1) and (2), the article including the reactor well cover is provided with a hatch that can be opened and closed.

(4) The freely openable hatch provided on the article including the reactor well cover covers the article including the reactor well cover so that the hatch can be freely opened and closed so as to overlap the article entrance on the fuel replacement floor. To lay down on the refueling floor.

In the refueling floor of the reactor building, beams, walls, and the like are provided around the large-size cargo entrance so as to support the load of the articles including the reactor well cover. Can be laid down using a part or the whole of the large cargo entrance. As a result, it is possible to secure a large area for performing the laydown and inspection work of the equipment on the fuel replacement floor, and to shorten the inspection period or reduce the size of the building by improving the inspection work efficiency.

Here, when the reactor well cover is laid down using all of the large cargo entrance, the large cargo entrance is blocked by the reactor well cover, and the loading / unloading operation cannot be performed. Therefore, if it is necessary to carry in and out inspection tools and materials during the inspection period, it is necessary to temporarily lift the reactor well cover with an overhead crane and lay down to another area.

Here, by installing a hatch that can be opened and closed on the reactor well cover, even when the large cargo entrance is set as a laydown space, only the hatch is lifted by an overhead crane and laid down to another area. Inspection tools and materials can be carried in and out.

At the refueling floor of the reactor building, beams, walls, etc. are installed around the large cargo entrance to support the load of articles including the reactor well cover, and a hatch is installed at the reactor well cover. This makes it possible to set the large cargo entrance as a lay-down space and lay down the reactor well cover without impairing the function of the large cargo entrance.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

The lay-down of the reactor well cover to the large cargo entrance 6 provided on the refueling floor of the reactor building was made possible by the following changes in the building structure.

FIG. 5 shows an example of a sectional view of the first embodiment.

Reactor well cover 7 around large cargo entrance 6
Beam 9 around large cargo entrance 6 so that it can support
Is installed, it is possible to lay down the reactor well cover 7 to the large cargo entrance 6.

FIG. 6 shows another example of a sectional view of the embodiment according to the first aspect.

Reactor well cover 7 around large cargo port 6
By installing the wall 10 around the large cargo entrance 6 so as to support the reactor, the reactor well cover 7 can be temporarily placed.

Here, as shown in FIG. 6, the reactor well cover 7 is laid down around the large material entrance 6 so that the upper surface of the reactor well cover 7 and the floor surface of the refueling floor 2 are at the same level. By doing so, the accessibility around the large cargo entrance 6 is also improved.

By setting the large cargo entrance 6 as a laydown space and laying down the reactor well cover 7 using part or all of the large cargo entrance 6, the equipment and facilities are laid down and inspected on the fuel replacement floor 2. A wide space for work can be secured, and the inspection period can be shortened or the building can be reduced by improving the inspection work efficiency. FIG. 7 shows a conventional structure around a large cargo entrance.

In this structure, no consideration is given to laying down the reactor well cover 7, and the structure cannot support the reactor well cover 7.

FIG. 3 shows a laydown situation at the time of inspection of a refueling floor of a conventional reactor building. In reactor building 1,
Large equipment such as a nuclear reactor is arranged. Maintenance and inspection are carried out for these devices every year, and disassembly and restoration of the devices are performed using an overhead crane installed above the operating floor 2.

Here, the reactor well cover 7 avoids the reactor well 3, the spent fuel pool 4, the equipment temporary storage pool 5, the large cargo entrance 6, etc., and the reactor well cover 7 in FIG.
Laying down at the temporary placement position limited the freedom of laying down.

In contrast to the conventional lay-down method for the reactor building 1 and the refueling floor 2 inside the building, in the present invention, beams, walls, etc. are installed around the large cargo entrance 2 to lay down the structure around the entrance / exit. Structure that can support the load of goods including the reactor well cover, it is possible to set the large cargo entrance 6 as a laydown space, increase the flexibility of laydown, reduce the inspection period and work efficiency. Therefore, it is possible to reduce the material cost and the construction cost of the reactor building by reducing the size of the building.

FIG. 2 shows a situation in which the large cargo entrance 6 is set as a laydown space and the reactor well cover 7 is laid down using the entire large cargo entrance 3.

When the large cargo entrance 6 is set as a laydown space and the reactor well cover 7 is laid down using the entire large cargo entrance 3, the large cargo entrance 3 is blocked by the reactor well cover 7. As a result, loading and unloading operations cannot be performed. Therefore, if it is necessary to carry in and out inspection tools and materials during the inspection period, it is necessary to temporarily lift the reactor well cover with an overhead crane and lay down to another area.

FIG. 4 shows a plan view of the third embodiment. Here, a hatch 8 that can be opened and closed is installed on the reactor well cover 7.

At the time of inspection of the refueling floor 2 of the reactor building 1,
When laying down the reactor well cover 7 to the large cargo entrance 3 and when it is necessary to carry in / out the articles from the operating floor to the ground floor for inspection, use the hatch 8 installed in the reactor well cover 7. Thus, articles can be carried in and out.

FIG. 1 shows an example of a plan view of the fourth embodiment.

An openable / closable hatch 8 provided on the reactor well cover 7 is overlapped with the large cargo entrance 6 and
The reactor well cover 7 is laid down on the refueling floor 2 so as to cover the large cargo entrance 6 so that the freely openable hatch 8 provided on the reactor well cover 7 enters the operation range of the overhead crane.

As described above, when the reactor well cover 7 is temporarily placed on the large cargo entrance 6 and laid down, when it is necessary to carry out the inspection article from the refueling floor to the ground floor, the reactor well cover is required. The goods can be carried in and out by using the hatch 8 installed in the large object 7.
Has the same function as the conventional one.

[0046]

According to the present invention, it is possible to shorten the inspection work process by increasing the degree of freedom of the lay-down work at the time of refueling floor inspection in the reactor building, or reduce the cost by reducing the building.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example in which an openable hatch provided on a reactor well cover is laid down so as to overlap with a large cargo port during inspection of a fuel replacement floor of a reactor building according to the present invention.

FIG. 2 is a plan view showing an example of a laydown at the time of refueling floor inspection of a reactor building of the present invention.

FIG. 3 is a plan view showing a laydown situation at the time of inspecting the operating floor of a conventional reactor building.

FIG. 4 is a plan view of an openable / closable hatch installed on a reactor well cover.

FIG. 5 is a cross-sectional view showing a structure around a large-size carry-in entrance as a structure capable of supporting a heavy object.

FIG. 6 is a cross-sectional view showing a structure around a large-size carry-in entrance as a structure capable of supporting a heavy object.

FIG. 7 is a cross-sectional view of a structure around a conventional large-size carry-in entrance.

[Explanation of symbols]

1 ... reactor building, 2 ... fuel replacement floor, 3 ... reactor well,
4: Spent fuel pool, 5: Temporary equipment pool, 6: Large cargo entrance, 7: Reactor well cover, 8: Hatch, 9 ...
Beam, 10 ... wall.

Continued on the front page (72) Inventor Tatsuya Otoshi 3-1-1, Sachimachi, Hitachi-City, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (72) Inventor Takanori Aramaki 1-2-2, Sachimachi, Hitachi-City, Ibaraki No. Within Hitachi Life Co., Ltd. (72) Norihide Toyama, Inventor 3-2-1 Sachimachi, Hitachi City, Ibaraki Prefecture Inside Hitachi Engineering Co., Ltd. (72) Sakae Ebata 3-chome, Sachimachi, Hitachi City, Ibaraki Prefecture No. 1 Inside Hitachi, Ltd. Hitachi Plant

Claims (4)

[Claims] In a reactor building provided with a loading / unloading port for articles provided on a refueling floor, a structure around the loading / unloading port can support a load of articles including a laid-down reactor well cover. Reactor building. 2. A method of laying down an article on a refueling floor in a reactor building, wherein the article including a reactor well cover is covered so as to cover a part or the entirety of an article loading / unloading port provided on the refueling floor. A laydown method for a refueling floor in a reactor building, characterized by laying down to a replacement floor. 3. The reactor building according to claim 1, wherein the article including the reactor well cover is provided with a hatch that can be opened and closed. 4. An article including a reactor well cover is covered by a freely openable hatch provided on an article including a reactor well cover so as to cover an article inlet / outlet provided on a fuel replacement floor. Laying down on the operating floor inside the reactor building, characterized by laying down to the refueling floor.