KR102510475B1 - Core catcher assembly and manufacturing method thereof - Google Patents

Abstract

A core catcher assembly is provided. The core catcher assembly includes a body plate; a subplate coupled to the body plate; and a tubular water box in which a core catcher body in a state in which the body plate and the sub plate are coupled is installed thereon.

Description

Core catcher assembly and manufacturing method thereof

The present invention relates to a modular core catcher assembly that can be easily installed and inspected in a common area of a reactor vessel and a manufacturing method thereof.

A core catcher is required among the handling facilities to ensure the safety of the containment building in the event of a major nuclear reactor accident. The co-current flow type core catcher is designed in the form of a rectangular pedestal with an inclination in consideration of the jet ejection effect, thermal erosion effect, spreadability and cooling capacity of the core melt released at the time of reactor vessel failure.

In the event of an accident, the melt discharged from the reactor vessel is uniformly distributed in the core catcher. After that, the cooling water stored in the reload water storage tank (IRWST) is supplied to the water box and the downcomer under the core catcher, and when the coolant is evaporated by heat transfer in the lower cooling channel, the reload water storage tank and the downcomer It is designed to be supplied to the lower cooling channel by natural force by the head pressure.

Since this core catcher is disposed under the reactor vessel, there are technical limitations for manufacturing and installation. For example, when the core catcher is manufactured in a separate form and supplied to the site, it is very difficult to weld and install the core catcher at the site because the common area of the reactor where the core catcher is installed is very narrow.

In addition, non-destructive (NDE) inspection and post-weld heat treatment (PWHT) work must be performed after installation, but these inspections and work are very difficult. In addition, since the period required for on-site installation of the core catcher increases, there is a problem that affects the economics of the nuclear power plant.

Korean Patent Publication No. 10-2016-0046134

The problem to be solved by the present invention is to improve the on-site welding and installation method, manufacture the modular core catcher in a modular form, post-heat treatment and inspection, and install it on the site, thereby shortening the construction period and reducing manufacturing / installation costs. It is to provide a catcher assembly and a manufacturing method thereof.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the following description.

A core catcher assembly according to one aspect of the present invention for achieving the above object includes a body plate; a subplate coupled to the body plate; and a tubular water box in which a core catcher body in a state in which the body plate and the sub plate are coupled is installed thereon.

In addition, a downcomer pipe facing upward may be installed on a side circumference of the water box.

In addition, a mounting frame for holding the water box may be further included, and the mounting frame may include a mounting portion provided under the water box and a vertical bar provided upward from a circumferential portion of the holding portion.

In addition, the body plate includes a central body and side bodies installed on a side surface of the central body. The central body has cladding performed on an upper surface of the central base, and the sub-side body comprises: After cladding is performed on the upper surface of, it may be subjected to a bending process.

In addition, the side body, based on the center body, the bottom portion is bent so that at least partially lifted to the upper side, the side portion may be bent to form a wall from the bottom portion toward the top.

Further, the sub-plate includes a sub-central body and a sub-side body installed on a side surface of the sub-central body, wherein the sub-central body has a cladding performed on an upper surface of the sub-central body, and the sub-central body is The body is bent after cladding is performed on the upper surface of the sub-side body, and cover plates may be installed on the outer sides of the sub-central body and the sub-side body.

In addition, the sub-side body may be bent so that the bottom part is lifted upwards at a certain angle with respect to the sub-central body, and the side part may be bent from the bottom part toward the top to form a wall.

In addition, the body plate and the sub plate may be previously welded together and transported to an installation site.

In addition, the welded parts of the body plate and the subplate may be transported to an installation site after post-heat treatment of a local heat treatment method and non-destructive inspection are performed.

In addition, a sacrificial material may be applied to an upper surface of the core catcher body.

A method for manufacturing a core catcher assembly according to an aspect of the present invention for achieving the above object includes: obtaining a core catcher body by combining a sub plate with a body plate to obtain a core catcher body; and obtaining a core catcher assembly by installing the core catcher body in a tubular water box to obtain a core catcher assembly.

In addition, the core catcher body and the water box may be transported to an installation site in a prefabricated state, and then combined and installed in the lower part of the reactor cavity.

In addition, a downcomer pipe facing upward may be installed on a side circumference of the water box.

In addition, a support frame 150 for holding the water box is provided, and the support frame may include a support portion provided under the water box and a vertical bar extending upward from a circumference of the support portion.

In addition, a central body processing step of performing cladding on the upper surface of the central body, a side body processing step of performing cladding on the upper surface of the side body and bending the cladding side body, A body plate acquisition step of acquiring the body plate by installing the central body and the side body to each other may be further included.

In addition, the side body, based on the center body, the bottom portion is bent so that at least partially lifted to the upper side, the side portion may be bent to form a wall from the bottom portion toward the top.

Also, the cladding may be made of a material including stainless steel.

In addition, the body plate and the sub plate may be made of a material including carbon steel.

In addition, a sub-central body processing step of performing cladding on the upper surface of the sub-central body, a sub-side body processing step of performing cladding on the upper surface of the sub-side body and bending the cladding of the sub-side body, , Further comprising a sub-plate obtaining step of obtaining the sub-plate by combining the sub-central body and the sub-side body, wherein a cover plate for closing the upper outer surface of the sub-central body and the sub-side body may be installed. .

In addition, the sub-side body may be bent so that the bottom part is lifted upwards at a certain angle with respect to the central body, and the side part may be bent from the bottom part toward the top to form a wall.

In addition, the body plate and the sub plate may be previously welded together and transported to a site.

In addition, in a state in which the body plate and the subplate are coupled, a post-heat treatment may be performed on a welded portion of the body plate and the subplate using a local heat treatment method.

According to the core catcher assembly and manufacturing method of the present invention as described above, there are one or more of the following effects.

According to the present invention, a core catcher assembly capable of shortening the construction period and reducing manufacturing/installation costs by manufacturing a modular core catcher in a modular form by improving the on-site welding and installation method, performing post-heat treatment and inspection, and installing the core catcher in the field, and its Manufacturing method can be provided.

1 is a perspective view showing a core catcher assembly according to an embodiment of the present invention.
Figure 2 is a cross-sectional view showing some of the components according to Figure 1;
Figure 3 is a perspective view showing some of the components according to Figure 1;
4 is an exploded perspective view illustrating components according to FIG. 3;
Figure 5 is a perspective view showing some of the components according to Figure 1;
6 is an exploded perspective view illustrating components according to FIG. 5;
Figure 7 is a combined perspective view showing the components according to Figure 1;
8 is an exploded perspective view illustrating components according to FIG. 7 .
9 is a flowchart sequentially illustrating a method for manufacturing a core catcher assembly according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention, and methods for achieving them, will become clear with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms, only the present embodiments make the disclosure of the present invention complete, and the common knowledge in the art to which the present invention belongs It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numbers designate like elements throughout the specification.

The spatially relative terms "below", "beneath", "lower", "above", "upper", etc. It can be used to easily describe the correlation between elements or components and other elements or components. Spatially relative terms should be understood as encompassing different orientations of elements in use or operation in addition to the orientations shown in the figures. For example, when flipping elements shown in the figures, elements described as “below” or “beneath” other elements may be placed “above” the other elements. Thus, the exemplary term “below” may include directions of both below and above. Elements may also be oriented in other orientations, and thus spatially relative terms may be interpreted according to orientation.

Although first, second, etc. are used to describe various elements, components and/or sections, it is needless to say that these elements, components and/or sections are not limited by these terms. These terms are only used to distinguish one element, component or section from another element, component or section. Accordingly, it goes without saying that the first element, first element, or first section referred to below may also be a second element, second element, or second section within the spirit of the present invention.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. As used herein, "comprises" and/or "comprising" means that a stated component, step, operation, and/or element is present in the presence of one or more other components, steps, operations, and/or elements. or do not rule out additions.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used in a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, the same or corresponding components regardless of reference numerals are given the same reference numerals, Description is omitted.

1 is a perspective view showing a core catcher assembly according to an embodiment of the present invention.

Referring to FIG. 1 , the core catcher assembly 100 may include a body plate 110, a sub plate 120, a water box 140, and a mounting frame 150. The body plate 110 may include a central body 111 and a side body 112 .

Here, the sub plate 120 may include a sub-center body 121 and a sub-side body 122 . The water box 140 may be provided with a down comer pipe 141. The mounting frame 150 may include a mounting portion 151 and a vertical bar 152 .

The body plate 110 is a tubular body having a predetermined shape, and an inside of the body plate 110 may be bent to form an inclined receiving space. The sub plate 120 may be coupled to the body plate 110 to form the core catcher body 130 .

Here, the body plate 110 and the sub plate 120 may be previously welded and transported to an installation site. The welded parts of the body plate 110 and the subplate 120 may be transported to an installation site after post-heat treatment in a local heat treatment method and non-destructive inspection are performed.

The central body 111 of the body plate 110 may be provided in the form of a board, for example. The side body 112 of the body plate 110 may be installed on at least one of both sides of the central body 111.

Figure 2 is a cross-sectional view showing some of the components according to Figure 1;

Referring to FIG. 2 , cladding may be performed on the upper surface of the central body 111 . In addition, cladding may also be performed on the upper surfaces of the side body 112, the sub-central body 121, and the sub-side body 122.

Figure 3 is a perspective view showing some of the components according to Figure 1; 4 is an exploded perspective view illustrating components according to FIG. 3;

Referring to Figures 3 to 4, the core catcher assembly 100 may be made of a partitioned structure. For example, it may be largely provided with a central body plate 110 and a sub plate 120 positioned on the side of the body plate 110.

Here, the subplate 120 may be installed on both sides of the body plate 110, respectively. For example, when one body plate 110 is composed of two subplates 120, these three parts are welded into one module in a factory, and the final post-heat treatment is to perform local heat treatment in consideration of the size of the electric furnace. can

Figure 5 is a perspective view showing some of the components according to Figure 4; Figure 6 is an exploded perspective view showing some of the components according to Figure 1;

Referring to FIGS. 5 and 6 , after cladding is performed on the upper surface of the central body 111, bending may be performed. The side body 112 may be bent so that the bottom portion 1121 is lifted at a certain angle to the upper side of the side with respect to the central body 111. The side portion 1122 of the side body 122 may be bent upward from the bottom portion 1121 to form a wall.

Figure 7 is a perspective view showing some of the components according to Figure 1; 8 is an exploded perspective view illustrating components according to FIG. 7 .

Referring to FIGS. 7 to 8 , the sub-side body 122 may be subjected to bending after cladding is performed on the upper surface of the side body 112 . More specifically, in the sub-side body 122, based on the sub-central body 121 of the sub-side body 122, the second bottom part 1221 of the sub-side body 122 is at a certain angle to the upper side of the side. It can be bent to be heard.

The second side portion 1222 of the sub-side body 122 may be bent upward from the second bottom portion 1221 of the sub-side body 122 to form a wall. Here, a cover plate 135 may be installed outside the sub-central body 121 and the sub-side body 122 .

In the water box 140, the body plate 110 and the sub plate 120 are coupled, that is, the core catcher body 130 may be installed upward. The water box 140 may be formed in a shape corresponding to the body plate 110 as a tubular body.

The water box 140 can also be manufactured as one module in a factory using the same manufacturing method as the body plate 110 and the sub plate 120, and post-heat treatment and inspection can be performed.

Here, a sacrificial material for in-depth defense may be provided on the upper surface of the core catcher body 130 . For example, such a sacrificial material may be installed with Lime Stone or the like. Meanwhile, the sacrificial material and the downcomer pipe 141 may be installed on site.

The downcomer pipe 141 may be installed on the side circumference of the water box 140. In this way, the downcomer pipe may be installed to face upward from the side circumference. The mounting frame 150 may mount the water box 140 .

The mounting portion 151 of the mounting frame 150 may be provided below the water box 140 . The vertical bar 152 of the mounting frame 150 may be provided upward from the circumference of the mounting portion 151 .

Meanwhile, hereinafter, a method for manufacturing a core catcher assembly (S100) will be described based on the foregoing.

1 to 8, the core catcher assembly manufacturing method (S100) of the present invention includes a central body processing step (S110), a side body processing step (S120), a body plate acquisition step (S130), and a sub-central body processing step. (S140), a sub-side body processing step (S150), a sub-plate acquisition step (S160), a core catcher body acquisition step (S170), and a core catcher assembly acquisition step (S180) may be included.

First, in the central body processing step (S110), cladding may be performed on the upper surface of the side body 112, which performs cladding on the upper surface of the central body 111 (see FIGS. 2 and 9).

In the side body processing step (S120), the cladding side body 112 may be bent. In the body plate acquisition step (S130), the body plate 110 may be obtained by installing the central body 111 and the side body 112 to each other (see FIGS. 5, 6 and 9).

In the sub-central body processing step (S140), cladding may be performed on the upper surface of the sub-central body 121 (see FIGS. 2 and 9).

In the sub-side body processing step (S150), cladding may be performed on the upper surface of the sub-side body 122 (see FIGS. 2 and 9). In the sub-side body processing step (S150), cladding is performed on the upper surface of the sub-side body 122, and the clad sub-side body 122 may be bent (see FIGS. 2, 7, 8, and 9 ).

In the sub-plate obtaining step (S160), the sub-plate 120 may be obtained by combining the sub-central body 121 and the sub-side body 122. Here, the sub-central body 121 and the sub-side body 122 may be provided with a cover plate 135 that closes the upper outside (see FIGS. 7, 8 and 9).

In the core catcher body acquisition step (S170), the core catcher body 130 may be obtained by combining the subplate 120 with the body plate 110 (see FIGS. 3, 4, and 9).

In the step of acquiring the core catcher assembly, the core catcher assembly 100 may be obtained by installing the core catcher body 130 in the tubular water box 140 . Here, the core catcher body 130 and the water box 140 may be respectively prefabricated, transported to an installation site, and then combined and installed in the lower part of the reactor cavity (see FIGS. 1 and 9 ).

A downcomer pipe facing upward may be installed on a side circumference of the water box 140 . Here, mounting frames 150 and 150 for holding the water box 140 may be provided.

The mounting frame 150 may include a mounting portion 151 provided under the water box 140 and a vertical bar 152 upward from the circumference of the mounting portion 151 (FIGS. 1 and 9). reference).

The side body 112 is bent so that the bottom part 1121 is at least partially lifted upwards on the side, based on the central body 111, and the side part 1122 is bent from the bottom part 1121 toward the top to form a wall. It can be (see FIGS. 5, 6 and 9).

Meanwhile, the cladding may be made of a material including stainless steel. The body plate 110 and the sub plate 120 may be made of a material including carbon steel.

The body plate 110 and the sub plate 120 may be previously welded together and transported to a site. In a state in which the body plate 110 and the subplate 120 are coupled, the welded portion of the body plate 110 and the subplate 120 may be subjected to post-heat treatment using a local heat treatment method.

Through the above description, in preparation for partial fabrication and on-site welding and installation methods, it is manufactured in a modular form at the factory, post-heat treatment and inspection, and installed on the site, thereby shortening the construction period as well as reducing the manufacturing / The effect of significantly reducing the installation cost can be derived.

Although the embodiments of the present invention have been described with reference to the above and accompanying drawings, those skilled in the art to which the present invention pertains can implement the present invention in other specific forms without changing the technical spirit or essential features. You will understand that there is Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting.

110: body plate
120: subplate
130: core gatcher body
140: water box
150: mounting frame

Claims (10)

body plate;
a subplate coupled to the body plate; and
Including a tubular water box in which a core catcher body in a state in which the body plate and the sub plate are coupled is installed on the top,
A core catcher assembly in which a downcomer pipe facing upward is installed on the side circumference of the water box. delete According to claim 1,
Further comprising a mounting frame for mounting the water box,
The mounting frame,
A core catcher assembly comprising a holder provided under the water box and a vertical bar provided upward from the circumference of the holder. According to claim 1,
The body plate,
It includes a central body and a side body installed on the side of the central body,
The central body has cladding performed on the upper surface of the central base,
The core catcher assembly, wherein the sub-side body is subjected to bending after cladding is performed on the upper surface of the side body. According to claim 4,
The side body,
Based on the central body, the bottom portion is bent so as to be lifted at least partially to the upper side, and the side portion is bent from the bottom portion toward the top to form a wall. According to claim 1,
The subplate,
It includes a sub-center body and a sub-side body installed on the side of the sub-center body,
In the sub-central body, cladding is performed on the upper surface of the sub-central body,
The sub-side body is bent after cladding is performed on the upper surface of the sub-side body,
A core catcher assembly, wherein cover plates are installed outside the sub-central body and the sub-side body. A core catcher body acquisition step of obtaining a core catcher body by combining the subplate with the body plate; and
A core catcher assembly obtaining step of obtaining a core catcher assembly by installing the core catcher body in a tubular water box,
A method of manufacturing a core catcher assembly, wherein a downcomer pipe facing upward is installed on the side circumference of the water box. According to claim 7,
A central body processing step of performing cladding on the upper surface of the central body;
A side body processing step of performing cladding on the upper surface of the side body and bending the cladding side body;
Further comprising a body plate obtaining step of obtaining the body plate by installing the central body and the side body to each other, the core catcher assembly manufacturing method. According to claim 8,
The side body,
Based on the central body, the bottom portion is bent so as to be lifted at least partially to the upper side, and the side portion is bent from the bottom portion toward the top to form a wall. According to claim 7,
A sub-central body processing step of performing cladding on the upper surface of the sub-central body;
A sub-side body processing step of performing cladding on the upper surface of the sub-side body and bending the cladding of the sub-side body;
Further comprising a sub-plate acquiring step of obtaining the sub-plate by combining the sub-central body and the sub-side body;
The core catcher assembly manufacturing method, wherein the sub-central body and the sub-side body are provided with a cover plate that closes the outer surface of the upper part.

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