JPS5814090A - Cooling device of reactor container - 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 The present invention relates to a cooling device for a reactor containment vessel that cools the atmosphere inside the reactor containment vessel, and particularly relates to a reactor pressure vessel (hereinafter referred to as “
The present invention relates to a cooling device for a nuclear reactor containment vessel that can uniformly cool the sides of an RPV (abbreviated as RP VJ), does not become an obstacle during periodic inspection of the RPV, and can quickly carry out inspection work.

In general, the reactor containment vessel is the RPV housed within the reactor containment vessel.
They tend to reach high temperatures due to heat dissipation from them. Therefore, the atmosphere inside the containment vessel is cooled by a cooling device in order to effectively protect other machines, measuring instruments, etc. housed within the containment vessel from thermal damage.

Here, to explain more specifically based on FIGS. 1 to 3, 1 is a conical containment vessel that houses the RPV 2, and this shields radiation from the RPV 2 and radioactive substances generated in the vicinity. It is made of concrete or steel. This containment vessel 1 is substantially RP
It is vertically divided into a dry well 3 that accommodates V2 and a subregion chamber 4 that suppresses the pressure in the dry well 3 in the event of an accident.

A cylindrical support base 6 made of steel or concrete is formed upright on the bottom 5 of the containment vessel 1, and an RPV 2 is supported and fixed to the upper end 7 of the support base 6. The upper end 7 has a side wall 2 of the RPV 2.
A heat insulating material 8 is erected so as to surround it along the direction a, and a shield wall 9 is formed to shield radiation from the RPV 2 by further surrounding it at a predetermined gap from the heat insulating material 8. has been done.

A cold air supply header 10 serving as a cooling device is installed along the circumferential direction of the gap A between the shield wall 9 and the heat insulation system 8 on the upper end 7 of the support base 6. As shown in FIG. 3, 10 forms a passage S through which materials, etc. are carried into the RPV 2 from a pair of manholes 11 (only 1 is shown in the illustrated example) provided symmetrically in the shield wall 9. Therefore, it has a shape that is divided into a pair of left and right circular arcs. And this header 1
Cold air is ejected upward from a cold air exhaust hole 12 provided at the bottom of the tank 1, thereby cooling the atmosphere on the side of the RPV 2 and inside the containment vessel 1 (dry well).

By the way, in the above-mentioned cooling device, the cold air supply header 10 is connected to two parts in order to form a passage S for carrying in materials (this is a passage that cannot be ignored because inspection equipment etc. are carried in).
Since the header 10 is divided, it is not only inconvenient that the sides of the RPV 2 cannot be cooled uniformly, but also when performing an ultrasonic flaw detection test on the RPV 2 during regular inspections, this header 10
There was also the problem that the header 10 formed of a thin plate or a thin plate was bent and deformed.

Furthermore, it was necessary to provide cold air supply pipes 13 (only 1 is shown in FIG. 2) for supplying cold air to each of the two divided headers 10.degree. 10, which was troublesome in construction.

The present invention was devised in order to effectively solve the above-mentioned problems, and its purpose is to uniformly cool the side of the RPVO and prevent it from becoming a hindrance during periodic inspections of the RPV. The object of the present invention is to provide a cooling device for a reactor containment vessel that allows this inspection work to be easily performed.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The same parts as those in the conventional example are designated by the same reference numerals and the description thereof will be omitted.

First, as shown in FIGS. 4 and 5, a cylindrical support stand 14 stands up from the bottom of the containment vessel, and is made of concrete or steel. A skirt 2b extending downward from the lower peripheral edge of the RPV 2 is mounted and fixed on the inner peripheral edge of the annularly formed upper end 14a of the support stand 14, and the skirt 2b extending downward from the lower peripheral edge of the RPV 2 is fixed to the side wall 2a and bottom 2c of the RPV2. Heat insulators 8, 8 are formed to surround the RPV 2, and are designed to minimize heat radiation from the RPV 2. This heat insulating material 8 is covered with a shield wall 9 erected at the outer peripheral edge of the support base upper end 14 with a predetermined gap therebetween, and is configured to shield radiation from the RPV 2. has been done.

A cooling device 15, which is a feature of the present invention, is provided at the upper end portion 14a of the support base 14 located between the shield wall 9 and the heat insulating material 8.

Specifically, the upper end 14 of the support stand 14. On the back surface 16 of the support base 14, that is, below the upper end surface 140 of the support base 14, an annular cold air supply means 17 and a continuous cold air supply passage 18 are formed along the circumferential direction of the upper end portion 14a of the support base 14. ing. A cold air transfer pipe 19 for supplying cold air from outside the system is connected to the supply passage 18 serving as the cold air supply means 17.

The upper end surface 14 is connected to the supply passage 18 from this point.
A large number of cold air injection holes 20 are formed along the circumferential direction of the R'PV 2 to inject cold air to the upper side of the R'PV 2 through the R'PV 2.
2 and the surrounding air inside the containment vessel 1 (dry well) can be uniformly cooled.

Next, as a modified embodiment, a configuration as shown in FIG. 6 may be adopted. That is, a large number of steel plates 21 are arranged in the vertical and horizontal directions.
... are welded together and concrete is filled between them to form the support base 22, the support base upper end 22
A section divided by the horizontal steel plate 21a and the vertical steel plate 21b is not filled with concrete, and this section is directly formed as the cold air supply passage 24 serving as the cold air supply means 23. Good too.

In this case, a ventilation hole 25 is formed in the vertical steel plate 21b to form a continuous annular passage 24 along the circumferential direction of the support base 22, and a ventilation hole 25 is formed in the horizontal steel plate 21a forming the upper end surface 26. A large number of cold air injection holes 27 are formed along the circumferential direction.

Next, the present invention will be explained in detail.

First, cold air is supplied through the cold air transfer pipe 19 into the cold air transfer passage 18 serving as the cold air supply means 17 .

The supplied cold air spreads throughout the annularly formed transfer passage 18 and passes through the seal wall 9 and the heat insulating material 8 through the cold air injection holes 20 formed above the support base 14.
It is uniformly injected into the gap between the RPV 2 and the side of the RPV 2.

This cold air uniformly cools the sides of the RPV 2 and cools the surrounding air inside the containment vessel 1 (dry well) while being discharged from the system through an exhaust system (not shown).

Further, since the entire cooling device 15 is incorporated into the support stand 14, this does not become an obstacle during periodic inspection of the RPV 2, and inspection work can be performed quickly and easily.

In the above embodiments, the shape of the cold air supply means was limited, but what would be possible if the cooling device itself could be built into a support stand and cool air could be uniformly injected to the sides of the RPV without protruding upwards? This may also be the case.

Also, as a nuclear reactor formation, so-called MARK-II
As for the shape, it goes without saying that it can be applied to other shapes as well.

In summary, according to the present invention, the following excellent effects can be achieved.

(1) There is no need to divide the cooling device or cold air supply means into two, and cold air can be injected uniformly to the RPvO side, so the RPvO side and the surrounding air inside the containment vessel (dry well) can be uniformly cooled. can do.

(2) Since the entire cooling device is built into the support stand, R
PV inspection work can be performed quickly and easily.

(3) One cold air transfer pipe to transfer cold air to the cooling device -7
- Construction is easy as only the required locations are required.

(4) By using the steel plate constituting the support stand as a cold air supply means, there is no need to manufacture a special device as a cooling device.

(5) Since the structure is simple, it can be easily designed and manufactured.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view showing the inside of the reactor containment vessel, Figure 2 is an enlarged view of section C in Figure 1 and is a vertical cross-sectional view showing a conventional cooling system, and Figure 3 is a vertical cross-sectional view of a conventional cooling system. 4 is a longitudinal sectional view showing a preferred embodiment of the present invention, FIG. 5 is a partial plan view of the same, and FIG. 6 is a longitudinal sectional view showing a modified embodiment. In the figure, 1 is the containment vessel, and 2 is the reactor pressure vessel (iPv).
), 14 and 22 are support stands, 15 is a cooling device, 16 is a back surface portion, 17.23 is a cold air supply means, and 20.27 is a cold air injection hole. Patent Applicant Ishikawajima Harima Heavy Industries Co., Ltd. Representative Patent Attorney Nobuo Kasuya 8- Ward U) Ward 470- Ward C) So

Claims (1)

[Claims] In a cooling device for a reactor containment vessel, in which a support is provided in the containment vessel, a reactor pressure vessel is supported on the support, and ambient air in a gap between the reactor pressure vessel and the containment vessel above the support is cooled. Cooling of a nuclear reactor containment vessel, characterized in that a cold air injection hole is formed in the support base below the gap, and a cold air supply means for supplying cold air to the cold air injection hole is provided on the back side of the support base. Device.