A main circuit isolation device for a high temperature gas-cooled reactor

Abstract

The present invention discloses a main circuit isolation device for a high-temperature gas-cooled reactor, including a valve body mechanism including a valve seat, a valve seat support body, a slip-on flange, an inner flow channel valve seat, an outer flow channel valve seat, a spring, a valve cover gasket and a valve cover. The valve stem mechanism includes a wedge-shaped swivel, a valve stem, a bracket, a control part, a wedge-shaped swivel rotating cylinder, a connecting part and a wedge-shaped swivel lifting multi-stage cylinder, as well as a conducting valve flap and a sealing valve flap. The entire mechanism controls the movement of the valve stem and the wedge-shaped swivel through the cylinder to realize the switching and regulating functions of the valve. The hidden dangers of water inflow accidents in the core are eliminated, the maintainability of the steam generator is improved, and the safety and advancement of the high-temperature gas-cooled reactor are improved.

Description

Technical Field

[0001] The invention relates to the field of nuclear equipment, in particular to a main circuit isolation device for a high-temperature gas-cooled reactor. Background Art

[0002] The high temperature gas-cooled reactor is an advanced nuclear energy system with the characteristics of the fourth generation, with inherent safety and high operating temperature. The primary pressure boundary of the high temperature gas-cooled reactor demonstration project consists of the reactor pressure vessel, hot gas duct and steam generator. The outer tube of the hot gas duct is connected to the reactor pressure vessel and steam generator respectively through slip-on flanges, forming a "shoulder-to-shoulder" arrangement, and the helium coolant pipeline connected to it up to (and including) the first isolation valve constitutes the primary pressure boundary.

[0003] The main helium blower is located at the top of the steam generator. It drives the helium coolant into the core through the outer tube of the hot gas duct to take out the heat generated by the fission of the nuclear fuel in the core. The temperature of the cold helium entering the reactor is 250℃. It is heated to 750℃ after passing through the core. The hot helium enters the steam generator through the inner sleeve of the hot gas duct for heat exchange, heats the secondary circuit water in the heat transfer tube, and generates 571℃ high-pressure superheated steam to drive the steam turbine generator to generate electricity. After the heat exchange is completed, the cold helium is sent back to the reactor core through the main helium blower, forming a closed helium cycle of the primary circuit system.

[0004] At present, the main helium loop system of the high-temperature gas-cooled reactor demonstration project has the following disadvantages:

[0005] 1. During the operation of the high-temperature gas-cooled reactor, once the steam generator heat transfer tube ruptures, the water vapor in the secondary circuit will quickly enter the primary circuit and enter the reactor core through the hot gas duct channel, and produce chemical reactions with a large amount of graphite materials in the core, posing a safety hazard;

[0006] 2. Steam generator equipment is in a high temperature and high pressure operating environment, especially high temperature components are extremely difficult to manufacture, resulting in a long equipment manufacturing cycle and a significant increase in power plant construction investment;

[0007] 3. The steam generator equipment is the weak link in the main equipment of the primary circuit of the high-temperature gas-cooled reactor. It maintains a direct connection with the reactor core, and the steam generator cannot be repaired.

[0008] The above problems bring great risks to the construction, safe operation and maintenance of high-temperature gas-cooled reactor nuclear power plants. Therefore, a high-temperature gas-cooled reactor main circuit isolation device is proposed this time.

[0009] At present, in-depth research work in this field has not been carried out at home and abroad. It is necessary to give full play to the inherent safety characteristics of high-temperature gas-cooled reactors and develop a main helium loop isolation device, which can greatly improve the safety of high-temperature gas-cooled reactors. Summary of the invention

[0010] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the title of the invention of this application to avoid blurring the purpose of this section, the abstract of the specification and the title of the invention, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0011] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0012] Therefore, the technical problem to be solved by the present invention is.

[0013] In order to solve the above technical problems, the present invention provides the following technical solutions: a high temperature gas-cooled reactor main circuit isolation device, comprising: a valve body mechanism, including a valve seat, a valve seat support body located outside the valve seat, a slip-on flange located outside the valve seat support body, an inner flow channel valve seat located inside the valve seat, an outer flow channel valve seat located between the inner flow channel valve seat and the valve seat, a spring located between the outer flow channel valve seat and the valve seat support body, a valve cover gasket located at the top end of the valve seat, and a valve cover located at the top end of the valve cover gasket; and,

[0014] The valve stem mechanism includes a wedge-shaped swivel located at the inner center of the valve seat, a valve stem is arranged on the top of the wedge-shaped swivel, a bracket is connected to the top of the valve cover, a control component is arranged on the outside of the upper end of the valve stem, a wedge-shaped swivel rotating cylinder is arranged on the outside of the control component, a connecting component is arranged on the top of the valve stem, a wedge-shaped swivel lifting multi-stage cylinder is arranged on the top of the connecting component, and a conducting valve flap and a sealing valve flap are respectively arranged on the outside of the wedge-shaped swivel.

[0015] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, a heat insulation component is arranged on the outer side of the inner flow channel valve seat.

[0016] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, a sliding bearing is provided at the connection between the valve stem and the valve cover.

[0017] As a preferred solution of the main circuit isolation device of the high-temperature gas-cooled reactor described in the present invention, the control component includes a wedge-type swivel arm sleeved on the outside of the upper end of the valve stem, a thrust pad is provided between the wedge-type swivel arm and the valve stem, and a cylinder inner swivel frame is provided on the outer side of the wedge-type swivel arm.

[0018] As a preferred solution of the high-temperature gas-cooled reactor main circuit isolation device described in the present invention, the connecting piece includes a cylinder lower connecting seat arranged at the top end of the valve stem, a cylinder upper connecting seat is arranged at the upper end of the cylinder lower connecting seat, and a plane thrust bearing is arranged at the connection between the cylinder lower connecting seat and the valve stem.

[0019] As a preferred solution of the main circuit isolation device of the high-temperature gas-cooled reactor described in the present invention, a valve stem seal is arranged on the upper part of the sliding bearing, the valve stem seal includes a valve stem packing, a packing spacer ring is arranged in the middle section of the valve stem packing, a packing sleeve is arranged on the outer side of the packing spacer ring, and a packing pressure plate is arranged on the outer side of the packing sleeve.

[0020] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, a pin shaft is arranged on the outer side of the conduction valve disc.

[0021] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, the conduction valve flap and the sealing valve flap are both connected to the wedge-type rotating body through a pin shaft.

[0022] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, an inner flow channel valve seat bellows is arranged between the inner flow channel valve seats.

[0023] As a preferred solution of the main circuit isolation device of the high temperature gas-cooled reactor described in the present invention, an outer flow channel valve seat bellows is arranged between the outer flow channel valve seats.

[0024] The beneficial effects of the present invention include eliminating the hidden danger of water ingress into the core, improving the maintainability of the steam generator, and enhancing the safety and advancement of the high-temperature gas-cooled reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0026] Figure 1 A schematic diagram of the structure of a load-bearing front component in a main circuit isolation device for a high-temperature gas-cooled reactor according to an embodiment of the present invention.

[0027] Figure 2 A schematic diagram of the structure of a load-bearing side component in a main circuit isolation device for a high-temperature gas-cooled reactor according to an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of the structural status of a load-bearing component in a main circuit isolation device for a high-temperature gas-cooled reactor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0030] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] Secondly, the present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0032] Furthermore, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0033] Example 1

[0034] Reference Figures 1-2 , this embodiment provides a main circuit isolation device for a high temperature gas-cooled reactor.

[0035] The main circuit isolation device of a high temperature gas-cooled reactor includes a valve body mechanism 100 and a valve stem mechanism 200 .

[0036] Specifically, the valve body mechanism 100 includes a hollow valve seat 101, both ends of the valve seat 101 are equipped with valve seat supports 102, and the outer side of the valve seat support 102 is equipped with a slip-on flange 103 for connecting to an external pipeline, the inner part of the valve seat 101 is provided with an inner flow channel valve seat 104 for heating helium to flow, and the outer part of the inner flow channel valve seat 104 is provided with an outer flow channel valve seat 105 for cooling helium to flow, that is, the outer flow channel valve seat 105 is provided with Springs 106 are arranged between the inner flow channel valve seat 104 and the valve seat 101, and at the inner ends of the inner flow channel valve seat 104 and the outer flow channel valve seat 105. A valve cover gasket 107 for sealing the valve seat 110 is also arranged on the top of the valve seat 101. At the same time, a valve cover 108 for closing the valve seat 101 is installed on the top of the valve cover gasket 107. The valve body and the valve cover adopt a flange connection structure and are sealed by a double sealing ring to retain the detachable and maintainable nature of the isolation device.

[0037] Furthermore, the valve body and the valve cover adopt a flange connection structure and are sealed by a double sealing ring to retain the disassembly and maintainability of the isolation device.

[0038] The valve stem mechanism 200 includes a wedge-shaped swivel 201 which is located at the inner center of the valve seat 101 and is arranged in a four-sided wedge shape. A valve stem 202 is arranged on the top of the wedge-shaped swivel 201. A bracket 203 is connected to the top of the valve cover 108. A control member 204 for controlling the rotation of the valve stem 202 is arranged on the outer side of the upper end of the valve stem 202, and a wedge-shaped swivel rotating cylinder 205 for pushing the wedge-shaped swivel to rotate and open and close is arranged on the outer side of the control member 204. At the same time, a connecting member 206 for supporting is arranged on the top of the valve stem 202, and a wedge-shaped swivel lifting multi-stage cylinder 207 for driving the valve stem 202 and the wedge-shaped swivel 201 to rise and fall is connected to the top of the connecting member 206. A conducting valve flap 208 and a sealing valve flap 209 are respectively installed on the adjacent sides of the wedge-shaped swivel 201, and the conducting valve flap 208 and the sealing valve flap 209 are symmetrically arranged about the wedge-shaped swivel 201.

[0039] Furthermore, the hot gas duct of the high-temperature gas-cooled reactor is a "cold-wrapped-hot" structure, the temperature of the hot helium in the main loop reaches 750°C, the temperature of the cold helium is 250°C, and the pressures of the cold and hot helium are about 7MPa. The "cold-wrapped-hot" structure makes the hot gas duct shell containing the cold helium belong to the pressure boundary, and the parts in contact with the high-temperature hot helium do not bear high pressure, thereby ensuring the overall safety of the hot gas duct. Similarly, the middle part of the wedge-type swirl 201 adopts a dual-channel conduction setting, and the conduction valve flap 208 is also an inner and outer ring isolation setting, that is, the inner and outer rings of the conduction valve flap 208 can be connected to the inner side ends of the inner flow channel valve seat 104 and the outer flow channel valve seat 105 respectively, and then connected to the inside of the wedge-type swirl 201 to form an inner and outer double-channel structure, and cooperate with the sealing valve flap 209 on the adjacent surface of the conduction valve flap. When the isolation device is connected to the "cold-wrapped-hot" hot gas duct, the isolation device can be connected or isolated to the cold and hot helium at the same time.

[0040] The outer side of the inner flow channel valve seat 104 is provided with a heat insulation component 109, and the heat insulation component material is silicon-based aerogel. The heat insulation component 109 can isolate the high temperature of the hot helium flowing through the inner flow channel valve seat 104 to a certain extent, and prevent the cold helium flowing through the outer flow channel valve seat 105 from being affected. (Considering that the temperature difference between the inner sleeve and the outer sleeve of the hot gas conduit reaches 500°C, the internal heat insulation structure takes into account the difference in thermal expansion between different components, so that the deformation of the isolation valve structure under hot and cold alternating conditions can be controlled, and the sealing performance is stable and reliable)

[0041] A sliding bearing 210 is provided at the connection between the valve stem 202 and the valve cover 108. The provision of the sliding bearing 210 can ensure stable and smooth rotation of the wedge-type rotating body 201 and the valve stem 202 inside the valve seat 101, thereby realizing the opening and closing operation of the valve.

[0042] Example 2

[0043] Reference Figures 1 to 3 , which is the second embodiment of the present invention, is based on the previous embodiment, and is different from the previous embodiment in that:

[0044] The control member 204 includes a wedge-type swivel arm 204a sleeved on the outer portion of the upper end of the valve stem 202, a thrust pad 204b is provided between the wedge-type swivel arm 204a and the valve stem 202, and the thrust pad 204b is similar to a thrust bearing and bears the axial support load, and a cylinder inner rotating frame 204c is provided on the outer side of the wedge-type swivel arm 204a, and the wedge-type swivel arm 204a is connected to the wedge-type swivel rotating cylinder 205 through the cylinder inner rotating frame 204c.

[0045] The connecting piece 206 includes a cylinder lower connecting seat 206a arranged at the top end of the valve stem 202, and a cylinder upper connecting seat 206b is arranged at the upper end of the cylinder lower connecting seat 206a. A planar thrust bearing 206c is arranged at the connection between the cylinder lower connecting seat 206a and the valve stem 202. The planar thrust bearing plays a role in supporting and transmitting axial force. The valve stem 202 is connected to the wedge-type swivel lifting multi-stage cylinder 207 through the connecting piece 206, and the use of the valve stem 202 is controlled by the wedge-type swivel lifting multi-stage cylinder 207.

[0046] Furthermore, the valve stem 202 is controlled by two pneumatic actuators, namely the wedge-type swivel rotating cylinder 205 and the wedge-type swivel lifting multi-stage cylinder 207, so as to realize operations such as swivel lifting, valve disc rotation, and swivel pressing down. The wedge-type swivel rotating cylinder 205 can provide a torque that meets the opening and closing requirements of the isolation device. At the same time, the two cylinders have a certain buffering function, which can reduce the impact caused during the opening and closing process, and can realize the rapid opening and closing of the isolation device with a ball valve structure.

[0047] Example 3

[0048] Reference Figures 1 to 3 , which is the second embodiment of the present invention, is based on the previous embodiment, and is different from the previous embodiment in that:

[0049] A valve stem seal 211 is further provided on the upper portion of the sliding bearing 210 .

[0050] Specifically, the valve stem seal 211 includes a valve stem packing 211 a as an assembly, and generally the main body thereof is made of graphite material.

[0051] In detail, a packing spacer ring 211b is provided in the middle section of the valve stem packing 211a, a packing press sleeve 211c is provided on the outer side of the packing press sleeve 211c, and a packing pressure plate 211d is provided on the outer side of the packing press sleeve 211c. A double-stage packing + spacer ring structure is adopted between the valve stem and the valve body, and a multi-pass sealing structure is formed during the rotation of the valve stem to effectively improve the leakage performance of the isolation device.

[0052] At the same time, pin shafts 212 penetrate through the four corners of the surfaces of the conducting valve flap 208 and the sealing valve flap 209 .

[0053] Furthermore, a flat hard seal is adopted between the wedge-type swivel 201 and the valve disc, and the four sides of the wedge-type swivel are polished to the required smoothness coefficient, usually with a roughness of 0.2. At the same time, the conducting valve disc 208 and the sealing valve disc 209 are connected to the wedge-type swivel 201 through the pin shaft 212 running through the four corners of the two, and the conducting valve disc 208 and the sealing valve disc 209 are respectively tightly fitted with the four sides of the smoothly polished wedge-type swivel 201 to achieve sealing between the wedge-type swivel and the spherical valve disc.

[0054] An inner flow channel valve seat bellows 213 is arranged between the inner flow channel valve seat 104, and an outer flow channel valve seat bellows 214 is arranged between the outer flow channel valve seat 105. The bellows are respectively welded to the valve seat and the valve seat support body to play a dynamic sealing role. For the seal between the wedge-type swivel 201 and the valve seat 101, a sealing structure of a double-channel spherical conduction valve disc or a sealing valve disc + inner sleeve double valve seat + outer sleeve double valve seat + valve seat spring + valve seat bellows is adopted. This structure is conducive to compensating for deformation caused by temperature and end load under high temperature conditions. The valve seat spring is a key component to ensure a reliable seal between the spherical valve disc and the valve seat. Materials suitable for high temperature environments are selected to provide an initial sealing pressure ratio for the valve seat and the valve disc, and provide a suitable preload.

[0055] The valve seat sealing surface is welded with hard alloy to reduce the wear of the valve seat sealing surface during the rotation of the spherical valve disc, thereby ensuring the sealing of the connection surface between the spherical valve disc and the valve seat.

[0056] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure of performing the function described herein, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0057] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0058] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0059] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A high temperature gas-cooled reactor main circuit isolation device, characterized in that: include, A valve body mechanism (100), comprising a valve seat (101), a valve seat support (102) located outside the valve seat (101), a slip-on flange (103) located outside the valve seat support (102), an inner flow channel valve seat (104) located inside the valve seat (101), an outer flow channel valve seat (105) located between the inner flow channel valve seat (104) and the valve seat (101), a spring (106) located between the outer flow channel valve seat (105) and the valve seat support (102), a valve cover gasket (107) located at the top end of the valve seat (101), and a valve cover (108) located at the top end of the valve cover gasket (107); and, The valve stem mechanism (200) comprises a wedge-shaped swivel (201) located at the inner center of the valve seat (101), a valve stem (202) is arranged on the top of the wedge-shaped swivel (201), a bracket (203) is connected to the top of the valve cover (108), a control member (204) is arranged on the outside of the upper end of the valve stem (202), a wedge-shaped swivel rotating cylinder (205) is arranged on the outside of the control member (204), a connecting member (206) is arranged on the top of the valve stem (202), a wedge-shaped swivel lifting multi-stage cylinder (207) is arranged on the top of the connecting member (206), and a conducting valve flap (208) and a sealing valve flap (209) are respectively arranged on the outside of the wedge-shaped swivel (201).

2. The high temperature gas-cooled reactor main circuit isolation device according to claim 1, characterized in that: A heat insulation component (109) is arranged on the outer side of the inner flow channel valve seat (104).

3. The high temperature gas-cooled reactor main circuit isolation device according to claim 1 or 2, characterized in that: A sliding bearing (210) is provided at the connection between the valve stem (202) and the valve cover (108).

4. The high temperature gas-cooled reactor main circuit isolation device according to claim 3, characterized in that: The control member (204) comprises a wedge-type swivel arm (204a) sleeved on the outside of the upper end of the valve stem (202), a thrust pad (204b) is provided between the wedge-type swivel arm (204a) and the valve stem (202), and a cylinder inner rotating frame (204c) is provided on the outer side of the wedge-type swivel arm (204a).

5. The high temperature gas-cooled reactor main circuit isolation device according to claim 4, characterized in that: The connecting member (206) comprises a cylinder lower connecting seat (206a) arranged at the top end of the valve stem (202), a cylinder upper connecting seat (206b) is arranged at the upper end of the cylinder lower connecting seat (206a), and a plane thrust bearing (206c) is arranged at the connection between the cylinder lower connecting seat (206a) and the valve stem (202).

6. The high temperature gas-cooled reactor main circuit isolation device according to claim 5, characterized in that: A valve stem seal (211) is arranged on the upper part of the sliding bearing (210), and the valve stem seal (211) includes a valve stem packing (211a), a packing spacer ring (211b) is arranged in the middle section of the valve stem packing (211a), a packing press sleeve (211c) is arranged on the outer side of the packing press sleeve (211c), and a packing pressure plate (211d) is arranged on the outer side of the packing press sleeve (211c).

7. The high temperature gas-cooled reactor main circuit isolation device according to claim 6, characterized in that: A pin shaft (212) is arranged on the outer side of the conduction valve flap (208).

8. The high temperature gas-cooled reactor main circuit isolation device according to claim 1 or 7, characterized in that: The conducting valve flap (208) and the sealing valve flap (209) are both connected to the wedge-type rotating body (201) via a pin shaft (212).

9. The high temperature gas-cooled reactor main circuit isolation device according to claim 8, characterized in that: An inner flow channel valve seat bellows (213) is arranged between the inner flow channel valve seats (104).

10. The high temperature gas-cooled reactor main circuit isolation device according to claim 9, characterized in that: An outer flow channel valve seat bellows (214) is arranged between the outer flow channel valve seats (105).

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