JPH04122393U - Reactor containment vessel vent pipe structure - Google Patents

Abstract

(57) [Summary] [Purpose] By forming a gap around the outer periphery of the vent pipe buried in concrete within the pedestal, a vent pipe structure for the reactor containment vessel is obtained in which thermal displacement is not restricted. [Configuration] Pedestal 2 supporting reactor pressure vessel 1
In the vent pipe structure in which a vent pipe 9 is provided for blowing steam generated in the upper dry well 4 into the suppression chamber 8, a lining 16 made of a sublimation agent is applied to the outer periphery of the vent pipe 9, and then the vent pipe is It is characterized in that the pipe 9 is buried in the concrete 10 of the pedestal 2.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention has been developed to prevent the occurrence of heat dissipation in the upper dry well of the pedestal supporting the reactor pressure vessel. A nuclear reactor with a vent pipe for blowing the steam into the suppression chamber. Regarding the vent pipe structure of the storage container.

0002

[Conventional technology]

In nuclear power generation facilities, etc., as shown in Figures 4 and 5, the reactor pressure vessel 1 is It is supported by a pedestal 2 and housed within a reactor containment vessel 3.

0003 Inside this reactor containment vessel 3, there is a An upper dry well 4 is formed in which piping (not shown) such as a main steam pipe is arranged, Below the diaphragm floor 5 of the dry well 4, the pedestal 2 and the outer A suppression chamber 8 containing pool water 7 divided by a peripheral wall 6 is formed. ing.

0004 In addition, as shown in the figure, there is a support in the pedestal 2 from the upper dry well 4. A vent pipe 9 communicating with the pool water 7 in the pressure chamber 8 extends in the circumferential direction. The vent pipes 9 are installed at appropriate intervals in the concrete of the pedestal 2. The steam generated in the upper dry well 4 is buried at the bottom of the well 10. (For example, steam leaking from the main steam pipe, etc.) is removed from the pool water in suppression chamber 8. A plurality of air outlets 11 are formed for blowing air into the air.

[0005] Since the reactor containment vessel 3 is constructed as described above, in the unlikely event that the upper dry well If leakage steam occurs in the suppression chamber 8, the steam is removed from the suppression chamber 8. It is designed so that it can be blown into the cooled water 7 and cooled and condensed.

[0006]

[Problem that the idea aims to solve] However, in the above-mentioned method, the steam in the upper dry well 4 is suppressed. When introducing the steam into the chamber 8, the vent pipe 9 is heated by the passing steam. Because the concrete 10 installed restricts thermal displacement, there is an excessive There is a problem that stress is generated and damages the branch part, and thermal expansion is restricted. Because they are bundled, the vent pipe 9 buckles inward, reducing the cross-sectional area of the flow path and impeding its function. There is a problem of being exposed.

[0007] Therefore, in order to solve the above problems, this invention was developed to solve the above problem. Reactor containment vessel vents that can tolerate thermal displacement of vent pipes buried in It is in providing the tube structure.

[0008]

[Means to solve the problem]

In order to achieve the above purpose, this invention has been developed for the vedestal that supports the reactor pressure vessel. , for blowing steam generated in the upper drywell into the suppression chamber. In a vent pipe structure with a vent pipe, a sublimation agent is added to the outer periphery of the vent pipe. After lining the vent pipe, the vent pipe is buried in the concrete of the pedestal. It is composed of

[0009]

[Effect]

According to the above configuration, when steam is generated in the upper dry well, the steam is is blown into the pool water of the suppression chamber from the upper dry well to cool it. It can be condensed.

0010 In addition, the vent pipe structure is preliminarily lined with a sublimation agent around the outside of the vent pipe. The vent pipe was buried in the concrete of the pedestal, so the sublimation agent naturally released. It can sublimate and form a gap between the outer circumference of the vent pipe and the concrete. This gap also allows steam to pass through the vent pipe and heat it. buckling as it can be thermally displaced freely without being constrained by concrete. In addition, the stress generated at branch parts, etc. can be significantly reduced. .

[0011]

【Example】

Hereinafter, one embodiment of the present invention will be described in detail based on the accompanying drawings.

0012 Figures 1 to 3 are diagrams illustrating an embodiment of the vent pipe structure of the reactor containment vessel of the present invention. It shows.

[0013] In the figure, 1 is a reactor pressure vessel, and this pressure vessel 1 is supported by a pedestal 2. and is housed inside the reactor containment vessel 3.

[0014] Inside this reactor containment vessel 3, there is a An upper dry well 4 is formed in which piping (not shown) such as a main steam pipe is arranged, Below the diaphragm floor 5 of the dry well 4, the pedestal 2 and the outer A suppression chamber 8 containing pool water 7 divided by a peripheral wall 6 is formed. ing.

[0015] Also, in the hedestal 2, there is a suppression check from the upper dry well 4. Vent pipes 9 communicating with the pool water 7 in the chamber 8 are installed at intervals in the circumferential direction. When the vent pipes 9 are buried in the concrete 10 of the pedestal 2, In both cases, the steam generated in the upper dry well 4 (e.g. from the main steam pipe, etc.) is A plurality of pipes for blowing out leaked steam) into the pool water 7 of the suppression chamber 8. An air outlet 11 is formed.

[0016] The pedestal 2 has an outer liner plate 12 and an inner liner plate 12, as shown in the figure. The outer liner plate 12 and the inner liner plate are formed into a double shell cylindrical shape. Concrete 10 is held between the side liner plates 13 at intervals in the circumferential direction. A partition plate 14 is provided, and each space partitioned by this partition plate 14 is Concrete 10 is placed in 15.

[0017] On the other hand, the vent pipe 9 is coated with a lining 16 of sublimation agent on its outer periphery. Concrete is placed intermittently in the spaces 15 and poured into these spaces 15. It is buried within the REIT 10.

[0018] The sublimation agent lining 16 is made of camphor, naphthalene, etc. at room temperature. A sublimating agent that naturally sublimates is used, and this is layered to surround the outer periphery of the vent pipe 9. lining to form a sublimation agent lining 16.

[0019] Note that cardboard or adhesive tape 17 is wrapped around the outer circumference of the sublimation lining 16. The outer periphery may also be protected.

[0020] Next, the operation of the above embodiment will be explained.

[0021] After applying sublimation agent lining 16 to the outer periphery of vent pipe 9 in advance, A pipe 9 is placed in the space 15 of the pedestal 2, and concrete 10 is poured around it. If provided, a vent pipe structure is formed.

[0022] If left in this state for a predetermined period of time, the sublimating agent line 16 will naturally sublimate and become as shown in Figure 4. As shown, a gap 18 is formed between the outer periphery of the vent pipe 9 and the concrete 10. be able to.

[0023] On the other hand, steam leaked from piping (not shown) such as the main steam pipe and the upper dry well 4 If steam is generated in the interior, the steam is guided to the vent pipe 9 and is supplied from the outlet 11. The water is blown into the pool water 7 of the compression chamber 8 to be cooled and condensed.

[0024] At this time, the vent pipe 9 is heated by the steam passing through the pipe, causing thermal displacement. Since a gap 18 is formed around the outer tube 9, the gap 18 allows the automatic Thermal displacement can be caused by

[0025] As a result, thermal displacement of the vent pipe 9 is not restricted, so it does not buckle. Furthermore, the stress generated at the branch portion can be reduced to an extremely low level.

[0026] Note that cardboard or adhesive tape 17 is wrapped around the outer circumference of the sublimation lining 16. If this is done, the external shape of the sublimation agent lining 16 will be checked when pouring the concrete 10. is maintained and a uniform gap 18 can be formed, and the poured concrete 1 The shape is not damaged by 0.

[0027]

[Effect of the idea]

In summary, according to the present invention, a lining made of a sublimation agent is placed around the outer circumference of the vent pipe. After that, the vent pipe was buried in the concrete of the pedestal. A gap can be formed around the vent tube.

[0028] Additionally, this gap allows for free thermal displacement without being constrained by concrete. This prevents the occurrence of buckling of the vent pipe, and also prevents the vent pipe from buckling. It is possible to reduce the stress generated at the branch part of the pipe to an extremely low level.

[Brief explanation of drawings]

FIG. 1 is a sectional view illustrating an embodiment of the vent pipe structure of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG. 1;

FIG. 3 is a sectional view taken along line BB in FIG. 2;

FIG. 4 is a sectional view illustrating the function of the vent pipe structure.

FIG. 5 is a sectional view illustrating a conventional example.

FIG. 6 is a sectional view taken along line CC in FIG. 5;

[Explanation of symbols]

1 Reactor pressure vessel 2 Pedestal 3 Reactor containment vessel 4 Upper dry well 7 Pool water 8 Suppression chamber 9 Vent pipe 10 Concrete 16 Sublimation agent lining

Claims (1)

[Scope of utility model registration request] Claim 1: A vent pipe structure in which a pedestal supporting a reactor pressure vessel is provided with a vent pipe for blowing steam generated in an upper dry well into a suppression chamber, wherein the outer periphery of the vent pipe is made of a sublimating agent. A vent pipe structure for a reactor containment vessel characterized by lining the vent pipe and then burying the vent pipe in concrete of a pedestal.