JPH0455794A - Nuclear reactor containment vessel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a nuclear reactor containment vessel, and particularly to a technique for arranging a dry well and a suppression chamber adjacent to each other inside and outside a side wall.

"Prior Art" As a conventional technology for a reactor containment vessel in a boiling water reactor, there is, for example, the technology shown in FIG. 4 of Japanese Utility Model Application No. 61-091190.

In the reactor containment vessel of this example in FIG.
Pressure suppression chamber (suppression chamber) 3 that stores W
, vent pipe 4, pressure suppression chamber nozzle 5, bellows joint 6,
A vent header 7, a downcomer 8, etc. are provided, and in the event that an accident such as a pipe breakage occurs and steam is ejected, an abnormal pressure increase inside the dry well 2 will cause the steam to be transferred to the vent pipe 4, vent header, etc. 7. By discharging into the pool water W via the downcomer 8, cooling and condensing it, the internal pressure of the dry well 2 is kept below a certain level and the integrity of the nuclear reactor is maintained.

The weight of the reactor pressure vessel 1 is determined by the foundation anchor 10 buried in the foundation 9 made of cast concrete, the bottom support 11 erected from the foundation anchor IO, and the steel support 11 on the bottom support 11. It has a structure in which it is supported by a reactor pedestal 13 and I that are erected from the bottom of the vessel 12.

"Problems to be Solved by the Invention" However, the structure as shown in FIG. 4 causes various problems as follows.

■The construction work of the reactor containment vessel and the construction work of the biological shielding wall (reactor building) 14, which is formed by pouring concrete around the reactor containment vessel, are interrelated, resulting in a long overall construction period. Things that are easy to happen, ■ Suppression chamber 3
The amount of equipment and parts related to this increases, and for example, since a part of the biological shielding wall 14 is interposed between the suppression chamber 3 and the bottom of the steel container I2, it is easy for the construction work to interfere with each other. (2) The internal structure of the suppression chamber 3 is such that the vent header 7 is arranged in an annular manner with respect to the vent pipe 4, and a plurality of downcomers 8 are arranged in the vent header 7. The amount of effort required to construct something.

The present invention has been made in view of the above circumstances, and has the following objectives: (1) simplifying the structure between the dry well and the suppression chamber; (2) shortening the construction period of the reactor containment vessel; 3
) The purpose of this is to reduce the number of parts in the internal structure of the sub-lens chamber.

"Means for Solving the Problems" The present invention proposes two means for solving the problems.

The first means includes a steel container that partitions and forms a dry well around the reactor pressure vessel, and a liner plate attached around the side wall of the steel container to a part of the side wall and the inner surface of the concrete structure. a plurality of vent pipes suspended from the ceiling structure of the suppression chamber and horizontally penetrating the side walls; and a downcomer connected to the vent pipes and communicating with the pool water of the suppression chamber. The reactor containment vessel is configured to include:

The second means includes a vacuum breaker valve provided at the outer end of the vent pipe, and a platform located near the vacuum breaker valve and supported by the inner wall of the suppression chamber. It is an additional reactor containment vessel.

"Function" In the first means, a dry well and a suppression chamber are arranged inside and outside the side wall of the steel container, so pressure based on the head difference of the pool water is applied to a part of the side wall. Deformation can be suppressed by increasing the strength of the material in advance. The construction of the side walls of the steel vessel is carried out separately from the concrete pouring work of the reactor building. In the suppression chamber part, the basic functions are provided by a vent pipe and a downcomer suspended from the ceiling, and the vent header is omitted.

In the second method, the platform is used to inspect the operation of the vacuum breaker valve attached to the end of the vent pipe.

[Embodiment J] Hereinafter, an embodiment of the reactor containment vessel according to the present invention will be described with reference to FIGS. 1 to 3. In the figure, parts common to the conventional example are given the same reference numerals to simplify the explanation.

In the reactor containment vessel in this embodiment, the steel vessel 20 that defines the dry well 2 around the reactor pressure vessel l has a foundation (concrete structure) 9 formed by pouring concrete. Basic anchor 10 in
The side wall 21 of the lower part of the steel container 20 is connected by welding or the like to the bottom liner 22 affixed to the upper surface of the base part 9, making the dry well 2 a sealed structure. A suppression chamber 3 using the side wall 21 as a part of a partition wall is arranged around 21.

The suppression chamber 3 is attached to a part of the side wall 21 of the steel vessel 20 and to the inner surface of the concrete structure 23 for the pressure suppression chamber of the reactor building 14, which surrounds the horizontal outside of the side wall 2I with a disc-shaped space. A sealed annular space is formed by the side liner plate 24, ceiling liner plate 25, and a portion of the bottom liner 22.

The suppression chamber 3 includes a steel container 20.
a plurality of vent pipes 4 horizontally penetrating the side wall 21 and extending outward; a downcomer 26 connected to the vent pipes 4 and having an opening positioned in the pool water W;
The downcomer 26 is attached to the concrete structure 2 for pressure suppression chamber.
A hanging tool 27 for hanging is arranged at 3.

More specifically, the inner end of the vent pipe 4 is attached to the side wall 21 by welding or the like, and as shown in FIG. , a Noet deflector 28 is attached to its inner end.

As shown in FIGS. 1 to 3, the downcomers 26 are provided, for example, four for each of the - vent pipes 4, and their lower openings are communicated with the pool water W.

Further, the bottom liner 22 of the try-well 2 and the bottom liner 22 of the suppression chamber 3 are arranged on the same plane by matching the level of the upper surface of the base part 9.

The reactor pedestal 13, like the side wall 21 described above,
It is erected directly from the foundation anchor 10 and bottom liner 22.

In the figure, reference numeral 29 is a vacuum breaker valve, 30 is a manhole, and 31 is a platform.
are provided in the circumferential direction along the upper inner wall of the suppression chamber 3, as shown in FIGS. 1 and 2, and the vacuum breaker valve 29 is located near the top of the platform 31. .

If the reactor containment vessel is configured as described above,
Even if the pressure difference between the dry well 2 and the upper space of the suppression chamber 3 is O, the pressure based on the head difference of the pool water W will be applied to the side wall 2I of the steel container 20. Reducing deformation and supporting integrity is achieved by considering the strength of the side wall 21.

As is clear from the comparison with the example in FIG. 4, there is no concrete-casting part near the side wall 21 of the steel container 20, and the weight of the side wall 21 is absorbed by the bottom liner 22 on the two sides of the foundation 9. The reactor building 14, which is directly supported and the surrounding concrete structure, and the reactor pedestal I3
This also simplifies the structure.

In the suppression chamber 3 section, the structure of the partition wall is simplified by utilizing the side wall 21 and bottom liner 22 of the steel container 20.

Since the construction work of the side wall 21 in the steel vessel 20 is separated from the concrete structure 23 for the pressure suppression chamber in the reactor building 14, it is carried out separately from the concrete casting work for that part.

Even if the various parts of the suppression chamber 3, the vent pipe 4, the downcomer 26, the hanging tool 27, the jet deflector 28, the vacuum breaker valve 29, etc. are assembled and installed during work, etc.
The weight of these devices is supported by the side wall 21, and after the concrete structure 23 for the pressure suppression chamber is constructed, the weight is also supported by the ceiling liner 25. and,
The vacuum breaker valve 29 is attached to the end of the vent pipe 4 using the platform 31, and even when inspecting the operation, the platform 31 is used to efficiently perform the work.

Considering the volume of suppression chamber 3,
As is clear from a comparison between FIG. 1 and FIG. 4, the suppression chamber 3 in FIG. and that there is no space left behind.
It has a rectangular cross-section surrounded by the side wall 2i, the bottom liner 22, the side liner 24, and the ceiling liner 25, which makes effective use of space, making it easy to increase the capacity.

Furthermore, the reactor pedestal 13 is constructed by erecting a steel double cylinder on the foundation anchor 10 and bottom liner 22 of the foundation part 9, and filling the inside with concrete.
Since the bottom liner 22 of the dry well 2 and subrection chamber 3 is flat, the steel container 2
0 and the suppression chamber 3 and can be carried out independently or in parallel.

On the other hand, if an accident such as a pipe rupture occurs in the dry well 2 and steam spews out, increasing the internal pressure of the dry well 2, the jet deflector 28 will reduce the impact caused by the jet flow and the pressure will increase. Fluid downcomer 26
By jetting out into the pool water W, the steam is cooled and condensed, thereby suppressing the pressure increase in the dry well 2. Note that when the pressure in the upper space of the suppression chamber 3 increases due to release of the pressure fluid, the vacuum breaker valve 29 is activated to prevent a pressure difference between the dry well 2 and the suppression chamber 3 from occurring.

"Effects of the Invention" As explained above, the reactor containment vessel according to the present invention provides the following excellent effects.

In the first invention, (1) the dry well and the suppression chamber are arranged adjacent to each other inside and outside the side wall of the steel container, so the structure of the partition wall of the suppression chamber can be simplified. ■The construction work of the steel vessel does not involve direct concrete pouring work, and the construction period for the entire reactor containment vessel can be shortened. ■Since there is no concrete structure between the dry well and the suppression chamber, the volumes of the dry well and suppression chamber can be increased.

In the second invention, since a vacuum breaker valve is provided at the outer end of the vent pipe and a platform is provided in the vicinity thereof, in addition to the effects of ■■■ in the first invention, Using Baum, you can easily install the vacuum breaker valve and check its operation.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing one embodiment of the reactor containment vessel according to the present invention, FIG. 2 is a view taken along the line ■-■ in FIG. 1, and FIG. 3 is a view taken along the line III-III in FIG. The arrow view and FIG. 4 are front sectional views showing a conventional example of a nuclear reactor containment vessel. 1...Reactor pressure vessel, 2...Dry well (3...Suppression chamber (pressure suppression chamber), 4...Vent pipe, 5... ...Pressure suppression chamber nozzle, 6...Bellows joint, 7...
...Bent header, 8...Downcomer, 9
...Foundation part, 10...Foundation anchor,
11...Bottom support, 12...Steel container, 13...Reactor pedestal, 14...
... Biological shielding wall (reactor building), 20 ... Steel container, 21 ... Side wall, 22 ... Bottom liner, 23 ... Pressure Concrete structure for suppression chamber, 24...Side liner, 25...
Ceiling liner, 26... Downcomer, 27...
... Hanging fixture, 28... Jet deflector,
29... Vacuum breaker valve, 30... Manhole, 31... Platform, W...
・Pool water. Figure 2 Applicant Ishikawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] i. A steel container that defines a dry well around a reactor pressure vessel, and a liner attached around a side wall of the steel container to a part of the side wall and to the inner surface of a concrete structure. a plurality of vent pipes suspended from the ceiling structure of the suppression chamber and horizontally penetrating the side walls; and a plurality of vent pipes connected to the vent pipes and communicating with the pool water of the suppression chamber. A nuclear reactor containment vessel characterized by comprising a downcomer. ii. a vacuum breaker valve provided at the outer end of the vent pipe;
The reactor containment vessel according to claim 1, further comprising a platform located near the vacuum breaker valve and supported by an inner wall of the suppression chamber.