WO2016122104A1

WO2016122104A1 - Heat insulating material mounting structure of steam generator of two-loop type pressurized light water reactor

Info

Publication number: WO2016122104A1
Application number: PCT/KR2015/013370
Authority: WO
Inventors: 문인득
Original assignee: 문인득
Priority date: 2015-01-29
Filing date: 2015-12-08
Publication date: 2016-08-04
Also published as: KR101619692B1

Abstract

A heat insulating material mounting structure of a steam generator of the present invention, for preventing the thermal expansion deformation of a sliding base below the steam generator by blocking the heat transferred from the steam generator provided in a nuclear reactor (1), comprises: a heat insulating material disposed along the lower surface of a stay cylinder of the steam generator and the upper inner surface of a skirt support; and a support plate that is disposed along the connection portion between the stay cylinder and the skirt support and includes a plurality of pieces for closely fixing the heat insulating material to the lower surface of the stay cylinder with a plurality of fixing bolts that pass through the skirt support from the inside to the outside thereof, thereby preventing the deflection of the heat insulating material, which is caused by vibration while the nuclear reactor (1) is being operated.

Description

Insulation structure of 2-loop pressurized water reactor steam generator

The present invention relates to a facility for insulating a steam generator provided in the reactor coolant system equipment, and more particularly, insulators, heat shields and a plurality of insulation cylinders in the stay cylinder and skirt support of the reactor steam generator. By using the supporting plate made of pieces to closely adhere the insulation to the lower part of the steam generator, the sagging of the insulation is completely prevented due to the vibration during the operation of the reactor, so that the high temperature of the steam generator is applied to the stagnated air area The present invention relates to a thermal insulation material mounting structure of a pressurized water reactor-type nuclear power plant steam generator for effectively preventing transmission to the sliding base and preventing structural vibration of the reactor coolant system according to thermal expansion deformation of the sliding base.

In general, nuclear power plants in Korea, for example, Conversetion Engineering (CE) System Plus 80 (Hanbit 3, 4), Korean standard nuclear power plants (Hanul 3, 4, 5, 6 and Hanbit 5, 6), OPR1000 (Shin-Gori 1,2), APR1400 (Shin-Gori 3,4, Shin-Uljin 1,2, UAE Nuclear Power Plants 1-4), 2-loop Pressurized Water Reactor.

Referring to Figure 1, the basic structure of such a reactor coolant system (hereinafter referred to simply as "reactor") is shown.

Such a reactor (1) is described in the Republic of Korea Patent Publication No. 10-1473665, "Pipe support device for replacing parts of nuclear power plant", the reactor coolant system (RC: Reactor Coolant System (RCS) 3: in the containment building 2) Is provided.

This reactor coolant system 3 has a reactor 5 containing a reactor and two heat transfer circuits 7 connected thereto.

In FIG. 1, two heat transfer circuits are shown connected in parallel to the reactor 5.

Each circuit 7 comprises a steam generator 9 and at least one coolant pump 11 for circulating coolant between the reactor 5 and the steam generator 9. Each circuit 7 includes three main pipes, the main pipe having a large diameter, connected to the main parts of the circuit. In addition, the circuit 7 includes a pressurizer 18 to keep the temperature and pressure of the coolant constant.

The first large diameter tubing or hot leg 13 is connected to one side of the reactor 5 and the inlet side of the coolant chamber of the steam generator 9 to be in contact with the core in the reactor 5. The heated coolant is sent to a steam generator (9).

The circulation pipe 15 called a cross-over leg connects one side of the discharge part of the coolant chamber of the steam generator 9 and one side of the vortex chamber suction part of the coolant pump 11.

The cold leg 17 connects between the vortex chamber of the coolant pump 11 and the reactor 5. In addition, the coolant cooled in the steam generator 9 and drawn out by the coolant pump 11 is transferred to the reactor 5 through the circulation pipe 15 and the low temperature pipe 7 to cool the core.

In such a reactor 1, each steam generator 9 has a substructure as shown in FIG. 2.

That is, the steam generator 9 has a stay cylinder 21 which is maintained at a high temperature, and a skirt support 23 of a cylindrical structure that supports it at the bottom thereof.

Such a skirt support 23 is fixed and supported by the stud bolt 32 on the sliding base 30 of the lower side, such a sliding base 30 is a forged anchor plate (40) And a plurality of, for example, four hemispherical sliders 42 provided on the bearing plate 41 to accommodate movement in response to thermal expansion occurring during operation of the reactor 1.

In addition, since the high temperature is generated during operation of the steam generator 9, the lower surface of the stay cylinder 21 and the heat insulating material 50 for preventing such high heat from being transmitted to the sliding base 30 of the lower part, It is attached to the skirt support 23 part.

Conventional thermal insulation material mounting structure is shown in detail in Figures 3a and 3b.

That is, in the conventional heat insulating material mounting structure, as shown in FIG. 3A, the heat insulating material 50 is generally disposed on the lower surface of the stay cylinder 21, and the cross-shaped (+) is formed to closely contact the stay cylinder 21 side. This is to utilize the insulation support 60 having the support arms (62).

The heat insulating material support 60 is the lower end is fixed to the sliding plate 30, the upper surface of the cruciform support arms 62 support the heat insulating material 50 to the stay cylinder 21 in close contact.

Alternatively, as shown in FIG. 3B, a hole is formed in the heat insulating material 50, and the heat insulating material 50 is formed by using a fixing member, for example, a plurality of mounting pins 70. ) To the bottom surface of the

However, such a conventional thermal insulation material mounting structure causes a problem that the thermal insulation material 50 sags downwardly over time due to vibration generated during operation of the reactor 1.

That is, the conventional heat insulating material mounting structure is not a structure that firmly tightly adheres the heat insulating material 50 to the bottom surface of the stay cylinder 21, it is not a structure that holds it as a whole, and as time passes, a part of the heat insulating material 50 is lowered The lower surface of the stay cylinder 21 is exposed.

In this way, when the insulation 50 sags and the lower surface of the stay cylinder 21 is exposed, high heat of the stay cylinder 21 is transferred to the inner cylindrical stagnated air area 80 of the skirt support 23. Radiation is transmitted, thereby heating the sliding base 30 causes a serious thermal deformation.

Problems related to this are described in detail below.

That is, the thermal insulation material 50 in the staganated air area 80 between the steam generator skirt support 23 and the sliding base 30 of the reactor 1 is installed in the coolant piping of the reactor. The local factor and vibration cause local dropout.

As a construction factor of the reactor piping, the final connection welding of the intermediate tube and the steam generator nozzle is left as a residual load on the sliding base 30 and the pump vertical support due to the welding shrinkage. As a result of this residual load, settlement of the sliding base 30 due to welding shrinkage occurs, and settlement typically occurs in the range of about 1 mm after installation of the steam generator 9 and after final connection welding.

This settlement can be seen as a load remaining in the sliding base 30, the residual load is characterized by increasing the frictional force on the sliding base 30 in the initial stage of the reactor 1 to inhibit the sliding operation in the lateral direction. .

In addition, when a gap occurs in the thermal insulation material 50 due to the vibration generated during the operation of the reactor (1), the thermal transfer (copy) phenomenon occurs locally in the sliding base 30 to increase the thermal deformation, usually the thermal insulation material (50) A high temperature of about 300 ° C. is transferred from the stay cylinder 21 to the sliding base 30 to cause thermal stress, and causes thermal deformation problems of the sliding base 30.

Such thermal deformation suppresses free movement due to thermal expansion of the sliding base 30 generated during operation of the nuclear power plant, or causes interference with surrounding structures on the upper part of the steam generator 9, and consequently, the steam generator 9 and the coolant pump. It causes structural vibration of (11).

As a result, this structural vibration causes the tubular wear and vibration stress of the steam generator 9, and in long cycle operation, boric acid accumulation causes boric acid embrittlement and fatigue of boron embrittlement in small diameter pipes, resulting in leakage of boric acid. .

In addition, when the sliding base 30 is thermally deformed, the steam generator 9 is inclined to operate as a result of the thermal deformation, and even after stopping at room temperature, a phenomenon in which the parts are shifted may appear in succession.

If the sliding base 30 is deformed and leveled as described above, the steam generator 9 is tilted, and as a result, the vibration stress due to the deformation and interference of the associated support structure of the reactor coolant pump 11 and the steam generator 9. This increases the (Vibration stress).

This vibration stress causes not only the tubular wear of the steam generator 9, but also the wear of the internal parts of the reactor coolant pump 11 and the fatigue cracking caused by fatigue in the pipe connected to the RCS system. It happens frequently.

Long period operation in such a state leads to the leakage of the mechanical seal of the reactor coolant pump 11 and the small diameter pipe.

Therefore, there is an urgent need in the art for the development of a technology capable of preventing the wear of the steam generator 9 due to the structural vibration of the reactor 1 and the wear of the reactor coolant system equipment.

An object of the present invention is to solve the conventional problems as described above, by improving the support structure of the thermal insulation material installed on the skirt support (skirt support) by reinforcing the structure to prevent the insulation material from falling, sliding base (sliding base) and A thermal insulation mounting structure of a nuclear reactor steam generator can be prevented from rising in the stagnated air area between skirt supports to prevent thermal deformation of the sliding base.

Another object of the present invention is to completely prevent local sagging of the thermal insulation material due to vibration of the facility during operation of the reactor, and to maintain the high temperature of the steam generator through the thermal insulation gap through the stagnated air area of the lower portion. It is to effectively prevent the transfer to the sliding base, to provide a heat insulating material mounting structure of the steam generator for preventing the occurrence of vibration of the reactor (1) due to the thermal expansion deformation of the sliding base.

In order to achieve the above object, the present invention, in the thermal insulation material mounting structure for preventing the thermal expansion deformation of the lower side sliding base by blocking the high heat transmitted from the steam generator provided in the reactor 1, the stay of the steam generator A heat insulating material disposed along the lower surface of the cylinder and the inner upper surface of the skirt support; And a support plate disposed along a connection portion of the stay cylinder and the skirt support and having a plurality of fixing bolts penetrating outwardly from the inner space of the skirt support to tightly fix the insulation to the bottom surface of the stay cylinder. It is configured to prevent sagging of the thermal insulation material due to vibration during operation of the reactor (1), wherein the support plate is made of a plurality of pieces, the support plate is made of an arcuate structure along the connecting portion of the stay cylinder and the skirt support It provides a heat insulating material mounting structure of the steam generator.

Preferably, with respect to the circumference formed by the connecting portion of the stay cylinder and the skirt support, it has a circumferential angle of 90 degrees, and four are disposed throughout the circumference and fixed along the entire rim of the insulation.

In addition, the present invention preferably, the support plate is each machined and manufactured in a curved cross-sectional structure corresponding to the contour formed by the connection portion of the stay cylinder and the skirt support, the connection portion of the stay cylinder and the skirt support With respect to the circumference to be formed, a bolt ball is formed at a circumferential angle of 30 degrees so that the fixing bolt is mounted.

And the present invention is preferably, the fixing bolt is disposed so that the head portion is disposed in the inner space of the skirt support to penetrate the support plate, the insulation and the skirt support from the inner space of the skirt support to the outside, the skirt support The penetrating threaded portion is fitted with a large diameter washer machined to have a surface coincident with the contour of the skirt support on the outside of the skirt support, and each fixed with a nut.

In addition, the present invention preferably, the heat insulating material is further provided with a heat shielding plate disposed to be in close contact with the entire lower surface, the heat shielding plate is fixed with a fixing bolt between the heat insulating material and the support plate to the heat insulating material of the stay cylinder It is in close contact with the bottom surface.

And the present invention preferably, the heat shield plate is formed with a rim of the curved cross-section whose edge coincides with the contour formed by the connecting portion of the stay cylinder and the skirt support, when joining with the support plate, This is in close contact with each other.

Preferably, further comprising a heat shield plate disposed in close contact with the surface of the sliding base, it is configured to prevent the transfer of radiant heat to the sliding base.

According to the present invention, the heat insulating material is disposed along the bottom surface of the stay cylinder of the steam generator and the inner top surface of the skirt support, and the heat insulating material is closely adhered to the bottom surface of the stay cylinder by using a heat shield plate and a support plate made of a plurality of pieces. Fix it. In addition, these support plates are each secured through a number of fastening bolts penetrating outward from the inner space of the skirt support, and through large diameter washers and nuts machined to have a surface coincident with the contour of the skirt support outside the skirt support. It is fixed.

Therefore, according to the present invention, during the operation of the reactor 1, it is possible to completely prevent the local sagging of the thermal insulation material due to the vibration of the installation, the high heat of the steam generator is sliding through the stagnated air area of the lower An improved effect can be obtained that completely prevents the transfer to the base, thereby minimizing thermal expansion deformation of the sliding base.

1 is an explanatory diagram showing a configuration of a reactor 1 facility of a general nuclear power plant.

Figure 2 is a cross-sectional view for explaining a heat insulating material mounting structure of the steam generator according to the prior art.

3A is an explanatory view showing a structure in which a heat insulating material support having a cruciform support arm supports a heat insulating material at a lower part of a stay cylinder in a heat insulating material mounting structure of a steam generator according to the related art.

3B is an explanatory view showing a structure in which a hole is formed in the heat insulating material in the steam generator according to the related art, and the heat insulating material is in close contact with the bottom surface of the stay cylinder by using mounting pins.

4 is a cross-sectional view illustrating a heat insulating material mounting structure of the steam generator according to the present invention.

5 is an exploded cross-sectional view showing a component configuration of the heat insulating material mounting structure of the steam generator according to the present invention.

Figure 6 is a perspective view of the components of the heat insulating material mounting structure of the steam generator according to the present invention, respectively showing the configuration of the heat insulating material, the heat shield plate and a plurality of support plates.

Figure 7 is an enlarged cross-sectional view showing a coupling cross section of the heat insulating material mounting structure of the steam generator according to the present invention.

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

The thermal insulation material mounting structure 100 of the steam generator according to the present invention, as shown in Figures 4 and 5 as a whole, in the lower portion of the steam generator 9 provided in the reactor 1, from the steam generator 9 to the lower By blocking the high heat transmitted to the, it is to effectively prevent the thermal expansion deformation of the lower side sliding base (30).

The heat insulating material mounting structure 100 of the steam generator according to the present invention includes a heat insulating material 110 disposed along the lower surface of the stay cylinder 21 of the reactor steam generator 9 and the inner upper surface of the skirt support 23. The heat insulating material 110 may be formed of a felt-type structure covering the entire lower surface of the stay cylinder 21.

And the thermal insulation material mounting structure 100 of the reactor steam generator according to the present invention, the heat shield plate 120 is provided on the lower surface of the thermal insulation material 110, such a heat shield plate 120 of the thermal insulation material 110 It is a disk-shaped structure arranged in close contact with the whole in the lower surface.

The structure of the heat insulating material 110 and the heat shield plate 120 is shown in detail as an exploded view in FIG.

That is, the heat insulating material 110 is made of a circular structure that corresponds to the circular lower surface of the stay cylinder 21, the heat shield plate 120 is a disc structure corresponding to the heat insulating material 110 in the lower portion of the heat insulating material (110) Is done.

The heat shield plate 120 forms an edge of a curved cross section whose edge 122 coincides with a contour formed by the connection portion of the stay cylinder 21 and the skirt support 23. The edge of the mold cross section achieves excellent results in that when the joining of the plurality of support plates 130 described below, the joining surfaces coincide with each other and are closely joined to each other.

In addition, the thermal insulation material mounting structure 100 of the reactor steam generator according to the present invention is disposed along the connecting portion of the stay cylinder 21 and the skirt support 23, the thermal insulation material 110 on the lower surface of the stay cylinder 21; It includes a support plate 130 consisting of a plurality of pieces to closely adhere to the.

Each of the support plates 130 is made of steel having an arc-shaped curved cross section, and the heat insulating material 110 and the heat through the plurality of fixing bolts 140 penetrating outward from the inner space of the skirt support 23. The blocking plate 120 is integrally fixed to the lower surface of the stay cylinder 21.

Each of the support plates 130, as shown in Figure 6, has an arc-shaped structure, the curvature of the arc-shaped structure is a circle along the connecting portion of the stay cylinder 21 and the skirt support 23 Match the arc-like structure, or curvature.

In addition, the support plates 130 preferably have a circumferential angle θ1 of 90 degrees with respect to the circumference formed by the connecting portion of the stay cylinder 21 and the skirt support 23, and four of the circumferences. It is disposed throughout and fixed along the entire edge of the thermal insulation (110).

The support plate 130 is machined and manufactured in a curved cross-sectional structure corresponding to the contour formed by the connecting portion of the stay cylinder 21 and the skirt support 23, respectively.

6, a plurality of bolt balls 132 are formed and fixed at a circumferential angle θ2 of 30 degrees with respect to the circumference formed by the connection portion of the stay cylinder 21 and the skirt support 23. Bolt 140 is mounted.

The fixing bolt 140 is arranged to penetrate outward from the inner space of the skirt support 23, such fixing bolt 140 is shown in detail in cross section in Figure 7, the head portion 142 is the It is disposed in the inner space of the skirt support 23 is disposed so as to pass through the support plate 130, the heat insulating material 110 and the skirt support 23 sequentially from the inner space of the skirt support 23.

In addition, the fixing bolt 140 is fixed to the threaded portion penetrating the skirt support 23 with the washer 144 and the nut 146 on the outside of the skirt support 23, such a washer 144 is a skirt support It consists of a large diameter washer 144 machined to have a surface consistent with the contour of 23, thereby effectively distracting the pulling stress of the fixing bolt 140 and allowing it to be more stably fixed by the nut 146.

Insulating material mounting structure 100 of the reactor steam generator according to the present invention configured as described above, as shown in the exploded view in Figure 5, arranging the insulating material 110 on the lower surface of the stay cylinder 21, heat shielding plate After the 120 is in close contact with the lower surface of the heat insulating material 110, the plurality of supporting plates 130 are disposed along the lower surface of the edge of the heat shield plate 120, and then using a plurality of fixing bolts 140 It is fixed to the skirt support (23).

When the heat insulating material 110 is fixed using the plurality of support plates 130 as described above, as shown in FIG. 4, the heat insulating material 110 is disposed on the entire bottom surface of the stay cylinder 21. It is in close contact by the state, the edge 112 of the heat insulating material 110 is firmly fixed to the connection portion of the stay cylinder 21 and the skirt support 23 over the entire circumferential direction by the support plates 130.

In addition, since the fixing bolts 140 fixing the support plates 130 are arranged such that their mounting direction penetrates outward from the inner space of the skirt support 23, the construction work is simple and very easy.

Then, the outer side of the skirt support 23 is fitted with a large diameter washer 144 machined to have a surface matching the contour of the skirt support 23, thereby more effectively dispersing the pull stress of the fixing bolt 140, The nut 146 is to be more stably fixed.

As described above, according to the present invention, since the heat insulating material 110 is tightly fixed to the lower surface of the stay cylinder 21 of the steam generator 9, the heat insulating material 110 is also caused by vibration generated during operation of the reactor 1. The local sag of) can be completely prevented.

Thus, the high heat of approximately 300 ° C. generated in the steam generator 9 can be effectively prevented from radiating transfer to the stagnated air area under the stay cylinder 21, thereby preventing heating of the sliding base 30. It is possible to minimize the thermal expansion deformation of the sliding base 30 as a result, and to achieve an excellent effect that can be stably operated by minimizing vibration of the reactor 1 facility.

Although the present invention has been described in detail with reference to the accompanying drawings, the present invention is not limited to such a specific structure. Those skilled in the art may variously modify or change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. For example, the support plates 130 may be arranged along a circumference formed by the connecting portion of the stay cylinder 21 and the skirt support 23 in the form of a plurality of pieces, not more than four pieces, or two or three or five or more shapes. It may be a structure that becomes. In addition, the fixing bolts 140 may also fix the support plates 130 through various arrangement intervals. In addition, although the heat shield plate 120 has been described with a single layer disc structure, it is a matter of course that the heat shield plate 120 may be formed of a plurality of layers or a plate layer structure of multiple layers. In addition, a heat shield plate may be installed on the sliding base surface to prevent radiant heat from being transferred to the sliding base. Nevertheless, such simple design modifications or variations will be made clear in advance that all obviously fall within the scope of the present invention.

[Revision 20.01.2016 under Rule 26]

Claims

In the thermal insulation material mounting structure for blocking the high heat transmitted from the steam generator provided in the reactor 1, to prevent thermal deformation of the lower side sliding base,

A heat insulating material disposed along the bottom surface of the stay cylinder of the steam generator and the inner top surface of the skirt support; And

And a support plate disposed along a connection portion of the stay cylinder and the skirt support, and having a plurality of fixing bolts penetrating outwardly from the inner space of the skirt support to tightly fix the insulation to the bottom surface of the stay cylinder. (1) is configured to prevent sagging of the thermal insulation material due to vibration during operation,

The support plate is composed of a plurality of pieces, the support plate is a heat generator mounting structure of the steam generator, characterized in that consisting of an arcuate structure along the connecting portion of the stay cylinder and the skirt support.
The circumference of the circumference formed by the connecting portion of the stay cylinder and the skirt support, has a circumferential angle of 90 degrees, four are arranged throughout the circumference and fixed along the entire rim of the thermal insulation material Insulation structure of steam generator.
2. The circumference of claim 1, wherein the support plate is machined and manufactured in a curved cross-sectional structure corresponding to the contour formed by the connection portion of the stay cylinder and the skirt support, and the circumference formed by the connection portion of the stay cylinder and the skirt support. And a bolt ball is formed at a circumferential angle of 30 degrees, so that the fixing bolt is mounted.
4. The fixing bolt of claim 3, wherein the fixing bolt is disposed in the inner space of the skirt support so as to penetrate the support plate, the insulation and the skirt support outward from the inner space of the skirt support. The screw portion is fitted with a large diameter washer machined to have a surface coincident with the contour of the skirt support on the outside of the skirt support, and is fixed with a nut, respectively.
The heat insulating material according to any one of claims 1 to 4, wherein the heat insulating material is further provided with a heat shielding plate arranged to be in close contact with the entire lower surface thereof, and the heat blocking plate is fixed with a fixing bolt between the heat insulating material and the support plate. Insulation material mounting structure of the steam generator, characterized in that to close contact with the heat insulating material to the lower surface of the stay cylinder.
6. The heat shielding plate according to claim 5, wherein the heat shield plate is formed with a curved cross section of edges whose edges coincide with the contours formed by the connecting portion of the stay cylinder and the skirt support, and the joining surfaces of the heat shield plates are mutually connected. Heat insulation material mounting structure of the steam generator, characterized in that the tightly coupled.
The steam generator according to any one of claims 1 to 4, further comprising a heat shield plate disposed in close contact with the surface of the sliding base to prevent radiant heat from being transferred to the sliding base. Thermal insulation material mounting structure.