Displacement compensation device for resisting earthquake

Abstract

The embodiment of the present invention discloses a displacement compensation device for resisting earthquakes, which includes a first bellows, a second bellows and a support member, wherein one end of the support member is connected to the first bellows, and the other end of the support member is connected to the second bellows, so that the first bellows and the second bellows are deformed respectively when subjected to earthquake loads, and are used to compensate for lateral displacement, which is a displacement in a direction perpendicular to the axes of the first bellows and the second bellows. This displacement compensation device for resisting earthquakes helps to compensate for the displacement difference between the equipment support in the reactor and the connecting pipe of the pressure vessel under earthquakes, and can also compensate for the thermal displacement difference between the equipment support in the reactor and the connecting pipe of the pressure vessel, thereby improving the compensation capacity in a limited space.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear reactors, and in particular to a displacement compensation device for resisting earthquakes. Background Art

[0002] Nuclear power structure is a major project of national energy strategy, with high construction cost. Once damaged by earthquake, it will lead to economic losses and difficult post-earthquake repair. my country is a country with many earthquakes, and ensuring the safety of nuclear reactors under earthquakes is a key issue. This requires that the equipment support compensation device in the reactor has good compensation ability during earthquakes, and in order to reduce the height of the equipment in the reactor, the equipment support compensation device needs to improve its compensation ability within a limited space. Summary of the invention

[0003] In view of the above problems, the present invention is proposed to provide a displacement compensation device for resisting earthquakes that overcomes the above problems or at least partially solves the above problems.

[0004] According to a first aspect of the present invention, there is provided a displacement compensation device for resisting earthquakes, comprising: a first bellows; a second bellows; a support member, one end of the support member being connected to the first bellows, and the other end of the support member being connected to the second bellows, so that the first bellows and the second bellows are deformed respectively when subjected to earthquake loads, for compensating for lateral displacement, wherein the lateral displacement is a displacement in a direction perpendicular to the axes of the first bellows and the second bellows.

[0005] Optionally, the first bellows and the second bellows are the same bellows.

[0006] Optionally, the single-wave axial displacement caused by the first bellows and the second bellows compensating for the lateral displacement is:

[0007]

[0008] Among them, D m is the average diameter of the first bellows or the second bellows, N is the number of waves of the first bellows or the second bellows, L b is the length of the corrugated section of the first bellows or the second bellows, L * is the distance between the center points of the first bellows and the second bellows, x is the axial compression or tension displacement compensated by the first bellows and the second bellows, y is the lateral displacement compensated by the first bellows and the second bellows, e y The first bellows and the second bellows are compensated for the single-wave axial displacement caused by the lateral displacement.

[0009] Optionally, the first bellows and the second bellows are stretched or compressed when subjected to the seismic load to compensate for axial displacement, where the axial displacement is displacement in the direction along the axis of the first bellows and the second bellows.

[0010] Optionally, the single-wave axial displacement caused by the first bellows and the second bellows compensating the axial displacement is:

[0011]

[0012] Wherein, x is the axial tensile or compressive displacement compensated by the first bellows and the second bellows, N is the wave number of the first bellows or the second bellows, e x The first bellows and the second bellows compensate for the single-wave axial displacement caused by the axial displacement.

[0013] Optionally, the device further includes a device body, wherein the first bellows, the second bellows and the support member are connected to the device body.

[0014] Optionally, the device body includes a fixed bracket, and one end of the first bellows is connected to the fixed bracket.

[0015] Optionally, the first bellows is welded to the fixing bracket.

[0016] Optionally, a support ring is provided at one end of the first bellows welded to the fixing bracket.

[0017] According to a second aspect of the present invention, there is provided a support for equipment within a reactor, comprising: a support body; and a displacement compensation device provided by the first aspect of the present invention, wherein one end of the displacement compensation device is connected to the support body.

[0018] According to a third aspect of the present invention, there is provided a reactor, comprising: a pressure vessel; supported by the reactor internal equipment provided by the second aspect of the present invention, one end of the displacement compensation device being connected to the pressure vessel.

[0019] Optionally, the pressure vessel includes a connecting pipe, and the displacement compensation device is connected to the connecting pipe.

[0020] The displacement compensation device for resisting earthquakes provided in an embodiment of the present invention helps to compensate for the displacement difference between the equipment support in the reactor and the connecting pipe of the pressure vessel under an earthquake, and can also compensate for the thermal displacement difference between the equipment support in the reactor and the connecting pipe of the pressure vessel, thereby improving the compensation capacity in a limited space. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other objects and advantages of the present invention will become apparent from the following description of the present invention with reference to the accompanying drawings, which will help to provide a comprehensive understanding of the present invention.

[0022] Figure 1 is a schematic structural diagram of a displacement compensation device for resisting earthquakes according to an embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of a first bellows and a second bellows compensating for lateral displacement according to an embodiment of the present invention;

[0024] Figure 3 Schematic diagram of a first bellows and a second bellows compensating for axial displacement according to an embodiment of the present invention.

[0025] It should be noted that the drawings are not drawn to scale, and for illustrative purposes, elements of similar structure or function are generally represented by similar reference numerals throughout the drawings. It should also be noted that the drawings are only for the convenience of describing the preferred embodiments, not the invention itself. The drawings do not illustrate every aspect of the described embodiments and do not limit the scope of the invention.

[0026] In the figure, 10 is a first bellows, 20 is a second bellows, 30 is a support member, 40 is a device body, and 41 is a fixing bracket. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiment is one embodiment of the present invention, not all embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should have the usual meanings understood by people with ordinary skills in the field to which the invention belongs. If the full text involves descriptions such as "first", "second", etc., the descriptions such as "first", "second", etc. are only used to distinguish similar objects, and cannot be understood as indicating or implying their relative importance, order of precedence, or implicitly indicating the number of technical features indicated. It should be understood that the data described by "first", "second", etc. can be interchangeable under appropriate circumstances.

[0029] A first aspect of an embodiment of the present invention provides a displacement compensation device for resisting earthquakes, comprising a first bellows 10, a second bellows 20 and a support member 30. Figure 1FIG. 1 is a schematic diagram of a displacement compensation device for resisting earthquakes according to an embodiment of the present invention. Figure 1 , one end of the support member 30 is connected to the first bellows 10, and the other end of the support member 30 is connected to the second bellows 20. This structure is a compound bellows structure, so that the first bellows 10 and the second bellows 20 are deformed separately when subjected to seismic loads, which is used to compensate for lateral displacement. The lateral displacement is the displacement in the direction perpendicular to the axis of the first bellows 10 and the second bellows 20. When subjected to seismic loads, the support member 30 may not be deformed under the action of external force, and the first bellows 10 and the second bellows 20 at both ends of the support member 30 may be deformed separately, thereby improving the lateral compensation capacity of the displacement compensation device. Optionally, the support member 30 may be a rigid support cylinder, and a rigid support is a support whose rigidity is much higher than the rigidity of the rotating shaft.

[0030] In the embodiment of the present invention, the first bellows 10 and the second bellows 20 can be the same bellows, that is, the first bellows 10 and the second bellows 20 have the same bellows wall thickness, wave height, wave pitch, bellows inner diameter, and single wave number. In other embodiments, according to different needs of actual conditions, the first bellows 10 and the second bellows 20 can also use different bellows. The bellows refers to a tubular elastic sensitive element connected by foldable corrugated sheets along the folding and telescopic direction. The bellows can be a metal bellows or a bellows expansion joint.

[0031] The bellows has the possibility of compression and tension compensation in various working conditions. Here, the maximum axial displacement allowed by a single corrugation is used. c and e e As the rated value of the bellows, the rated value is the displacement value caused by the rated load, that is, the working displacement allowed under normal use conditions. These values ​​are set according to the physical limitations of the displacement capacity of the bellows. The physical limitations here include the size of the space where the bellows is located, etc.

[0032] Under compression, the single wave equivalent total displacement of the compound bellows is:

[0033] e c (Calculated value)≤e cmax (Rated value, maximum value)

[0034] The single-wave equivalent total displacement here refers to the equivalent displacement value generated by a single corrugation of a compound bellows under compression. Equivalent refers to a quantity equivalent to a specific or commonly established numerical value.

[0035] The compression displacement of the compound bellows is: e cmax =q-2r m -nt

[0036] Where: q is the wave distance, rm is the average radius of the compound bellows, n is the number of material layers, t is the nominal wall thickness of a single layer of material, and the nominal wall thickness is the theoretical wall thickness.

[0037] The maximum total compression displacement e allowed by a given single wave c =e cmax

[0038] The maximum allowable total compression displacement of a single wave is:

[0039]

[0040] Where: e θ K is the single-wave axial displacement caused by the compound bellows absorbing the angular displacement θ. The single-wave axial displacement is the displacement of a single corrugation in the axial direction of the compound bellows. θ is the internal pressure influence coefficient of angular displacement.

[0041] The compound bellows absorbs the total axial compression displacement x, and the resulting single-wave axial displacement is:

[0042]

[0043] The compound bellows absorbs the total lateral superposition displacement y, and the resulting single wave axial displacement is:

[0044]

[0045] Where: D m is the average diameter of the corrugation of the compound bellows, N is the number of waves of a single bellows in the compound bellows, L b L is the length of the corrugated section of a single bellows in a compound bellows. * is the distance between the center points of the two bellows in the compound bellows, x is the total displacement of the compound bellows absorbing axial compression superposition, and y is the total displacement of the compound bellows absorbing lateral superposition.

[0046] In the tensile state, the single wave equivalent total displacement of the compound bellows is:

[0047] e e (Calculated value)≤e emax (Rated value, maximum value)

[0048] The single-wave equivalent total displacement here refers to the equivalent displacement value generated by a single corrugation of the compound bellows under tension.

[0049] Tensile displacement of compound bellows: e emax =6r m -q

[0050] Where: q is the wave distance, r m is the average radius of the compound bellows.

[0051] The maximum total tensile displacement e allowed by a given single wave e =e emax

[0052] The maximum allowable tensile displacement of a single wave is calculated according to

[0053]

[0054] Where: e θ K is the single wave axial displacement caused by the compound bellows absorbing the angular displacement θ. θ is the internal pressure influence coefficient of angular displacement.

[0055] The compound bellows absorbs the total axial tensile displacement x, and the resulting single-wave axial displacement is:

[0056]

[0057] The compound bellows absorbs the total lateral superposition displacement y, and the resulting single wave axial displacement is:

[0058]

[0059] The embodiment of the present invention adopts a compound bellows structure, and the angular displacement internal pressure influence coefficient K θ =1. Since the displacement compensation device provided by the embodiment of the present invention is used on the equipment support in the reactor, and the equipment support has no torsion, the compound bellows absorbs the single-wave axial displacement e caused by the angular displacement θ. θ is 0.

[0060] In the embodiment of the present invention, a compound bellows structure is selected, that is, a first bellows 10 and a second bellows 20 are selected for displacement compensation. When the first bellows 10 and the second bellows 20 are compressed or stretched, the first bellows 10 and the second bellows 20 compensate for the lateral displacement of the single wave axial displacement caused by:

[0061]

[0062] Among them, D m is the average diameter of the corrugations of the first bellows 10 or the second bellows 20, N is the number of waves of the first bellows 10 or the second bellows 20, L b is the length of the corrugated section of the first bellows 10 or the second bellows 20, L * is the distance between the center points of the first bellows 10 and the second bellows 20, x is the compensation axial compression or tension displacement of the first bellows 10 and the second bellows 20, Figure 2 is a schematic diagram of the first bellows and the second bellows compensating for lateral displacement according to an embodiment of the present invention, see Figure 2, y is the lateral displacement compensated by the first bellows 10 and the second bellows 20, e y = L is the single wave axial displacement caused by the first bellows 10 and the second bellows 20 compensating for the lateral displacement. From the above formula, it can be seen that the distance L between the center points of the first bellows 10 and the second bellows 20 is * The lateral compensation capability can be improved by increasing the distance L between the center points of the first bellows 10 and the second bellows 20. * , so that the first bellows 10 and the second bellows 20 compensate for the single wave axial displacement e caused by the lateral displacement y Increased, thereby improving the lateral compensation ability.

[0063] The first bellows 10 and the second bellows 20 are stretched or compressed when subjected to earthquake loads to compensate for axial displacement. The axial displacement is the displacement along the axis of the first bellows 10 and the second bellows 20 .

[0064] Figure 3 is a schematic diagram of the first bellows and the second bellows compensating for axial displacement according to an embodiment of the present invention, see Figure 3 , the single-wave axial displacement caused by the first bellows 10 and the second bellows 20 compensating for the axial displacement is:

[0065]

[0066] Wherein, x is the axial tensile or compressive displacement compensated by the first bellows 10 and the second bellows 20, N is the wave number of the first bellows 10 or the second bellows 20, e x The single wave axial displacement caused by the first bellows 10 and the second bellows 20 compensating the axial displacement. In the embodiment of the present invention, a compound bellows structure is adopted, that is, the first bellows 10 and the second bellows 20 are used for displacement compensation, so that the axial compensation capacity is the sum of the two bellows.

[0067] The displacement compensation device provided by the embodiment of the present invention further includes a device body 40, and the first bellows 10, the second bellows 20 and the support member 30 are connected to the device body 40. Optionally, the first bellows 10, the second bellows 20 and the support member 30 can be connected to both sides of the device body 40.

[0068] The device body 40 includes a fixing bracket 41, and one end of the first bellows 10 is connected to the fixing bracket 41, which is used to eliminate the pressure thrust of the first bellows 10 and the second bellows 20, so that the first bellows 10 and the second bellows 20 can work normally and perform displacement compensation.

[0069] The first bellows 10 may be welded to the fixing bracket 41 .

[0070] A support ring is provided at one end of the first bellows 10 welded to the fixed bracket 41, and the support ring is used to protect the weld and improve the imbalance of heat transfer when the first bellows 10 and the fixed bracket 41 are welded. Optionally, the support ring can be a liner ring. Optionally, the first bellows 10 can be provided with a connecting end for connecting to the fixed bracket 41, and the second bellows 20 can also be provided with a connecting end for connecting to the device body 40.

[0071] According to the second aspect of the present invention, a reactor internal equipment support is provided, comprising a support body and a displacement compensation device provided by the first aspect of the present invention, one end of the displacement compensation device being connected to the support body. The displacement compensation device provided by the embodiment of the present invention can be used on the reactor internal equipment support to compensate for the displacement difference between the equipment support and the pressure vessel under earthquake. The reactor pressure vessel refers to a closed container that houses a nuclear reactor and withstands its huge operating pressure. It is one of the three radioactive protection barriers and a key core equipment of a nuclear power plant. The reactor here can be a Chinese demonstration fast reactor, which is a fast neutron reactor and refers to a nuclear fission reactor without a neutron moderator. The Chinese demonstration fast reactor is located at a location with an earthquake intensity of 9. During an earthquake, the displacement compensation of the equipment support and the pressure vessel becomes the primary functional requirement of the compensation device. The equipment in the reactor includes a main pump, a heat exchanger, etc. In order to reduce the height of the main pump, heat exchanger and other equipment in the reactor, the space of the equipment support compensation device is limited. The displacement compensation device provided by the embodiment of the present invention adopts a compound bellows structure to improve the compensation capacity in a limited space.

[0072] According to a third aspect of the present invention, there is provided a reactor, comprising a pressure vessel and the reactor internal equipment support provided by the second aspect of the present invention, wherein one end of the displacement compensation device is connected to the pressure vessel.

[0073] The pressure vessel comprises a connecting pipe, and the displacement compensation device is connected to the connecting pipe.

[0074] The displacement compensation device for resisting earthquakes provided in the embodiment of the present invention can be used on the equipment support in the reactor. When space is limited, the lateral compensation capacity of the bellows can be improved through the structural form of the compound bellows, so as to compensate for the displacement difference between the equipment support in the reactor and the pressure vessel connecting pipe under earthquake, and avoid the destruction of the containment boundary of the bellows due to insufficient compensation capacity of the seismic load. At the same time, it can also compensate for the thermal displacement difference between the equipment support in the reactor and the pressure vessel connecting pipe under different working conditions. The equipment support in the reactor generates thermal displacement due to the heat generated by the reactor core, and the pressure vessel connecting pipe generates thermal displacement due to the heat generated by the reactor core. The thermal displacement difference is the difference between the thermal displacement generated by the equipment support and the thermal displacement generated by the pressure vessel connecting pipe.

[0075] In an embodiment of the present invention, the displacement compensation device can be used on the intermediate heat exchanger support on the Chinese Demonstration Fast Reactor. The displacement compensation device is located above the intermediate heat exchanger support, one end is welded to the intermediate heat exchanger support, and the other end is welded to the connecting pipe of the corresponding pressure vessel. Since the displacement compensation device adopts a compound bellows structure, it has sufficient compensation capacity during an earthquake, and can prevent the radioactive gas in the reactor from escaping, play a sealing role, and at the same time compensate for the thermal displacement difference between the pressure vessel and the intermediate heat exchanger support. Since the thermal displacement of the intermediate heat exchanger support is greater than the thermal displacement of the reactor pressure vessel connecting pipe, the bellows is in a compressed state. The first bellows 10 and the second bellows 20 can adopt multi-layer and multi-wave bellows, the bellows wall thickness is 0.5mm, the number of layers is 5, the wave height is 40mm, the wave pitch is 55mm, the inner diameter of the bellows is 2860mm, and the number of single waves is 7 waves. After calculation and analysis, the compensation capacity that the bellows needs to achieve is: thermal displacement compensation is 32mm axial displacement and 9mm lateral displacement; 4mm axial displacement and 23mm lateral displacement under SL1 earthquake. SL1 earthquake refers to the safe operation earthquake under Chinese standards. For low-level earthquake motion, the nuclear power plant is required to maintain normal and safe operation after the earthquake; 5mm axial displacement and 33mm lateral displacement under SL2 earthquake. SL2 earthquake refers to the extreme safety earthquake under Chinese standards. For high-level earthquake motion, the nuclear power plant is required to maintain safety and prevent the leakage of radioactive materials. Through practice, the above-mentioned thermal displacement and seismic displacement compensation capabilities are achieved through the compound bellows structure. In some embodiments, the displacement compensation device provided by the present invention can be used on the support of the independent heat exchanger on the Chinese demonstration fast reactor. In other embodiments, the displacement compensation device can also be used on the support of other equipment in the fast reactor, for example, on the support of the main pump in the fast reactor.

[0076] Regarding the embodiments of the present invention, it should also be noted that, in the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0077] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A displacement compensation device for resisting earthquakes, characterized in that: include: A first bellows (10); A second bellows (20); A support member (30), one end of the support member (30) being connected to the first bellows (10), and the other end of the support member (30) being connected to the second bellows (20), so that the first bellows (10) and the second bellows (20) are deformed respectively when subjected to earthquake loads, so as to compensate for lateral displacement, wherein the lateral displacement is displacement in a direction perpendicular to the axes of the first bellows (10) and the second bellows (20); The displacement compensation device is used on a device support in a reactor, the device support is free of torsion, and the single-wave axial displacement caused by the first bellows (10) and the second bellows (20) absorbing the angular displacement is 0; The displacement compensation device further comprises a device body (40), and the first bellows (10), the second bellows (20) and the support member (30) are connected to the device body (40); The device body (40) comprises a fixing bracket (41), and one end of the first corrugated tube (10) is connected to the fixing bracket (41).

2. According to the displacement compensation device of claim 1, the first bellows (10) and the second bellows (20) are the same bellows.

3. The displacement compensation device according to claim 1, characterized in that: The single-wave axial displacement caused by the first bellows (10) and the second bellows (20) compensating for the lateral displacement is: in, is the average diameter of the corrugations of the first corrugated tube (10) or the second corrugated tube (20), N is the number of waves of the first corrugated tube (10) or the second corrugated tube (20), is the length of the corrugated section of the first corrugated tube (10) or the second corrugated tube (20), is the distance between the center points of the first bellows (10) and the second bellows (20), x is the axial compression or tension displacement compensated by the first bellows (10) and the second bellows (20), y is the lateral displacement compensated by the first bellows (10) and the second bellows (20), The first bellows (10) and the second bellows (20) are used to compensate for the single-wave axial displacement caused by the lateral displacement.

4. The displacement compensation device according to claim 1, characterized in that: The first bellows (10) and the second bellows (20) are stretched or compressed when subjected to the seismic load, so as to compensate for axial displacement, wherein the axial displacement is displacement in the direction along the axis of the first bellows (10) and the second bellows (20).

5. The displacement compensation device according to claim 4, characterized in that: The single-wave axial displacement caused by the first bellows (10) and the second bellows (20) compensating for the axial displacement is: Wherein, x is the axial tensile or compressive displacement compensated by the first bellows (10) and the second bellows (20), N is the wave number of the first bellows (10) or the second bellows (20), The first bellows (10) and the second bellows (20) are compensated for the single-wave axial displacement caused by the axial displacement.

6. The displacement compensation device according to claim 1, characterized in that: The first corrugated pipe (10) is welded to the fixing bracket (41).

7. The displacement compensation device according to claim 6, characterized in that: One end of the first bellows (10) welded to the fixing bracket (41) is provided with a supporting ring.

8. A support for equipment inside a reactor, characterized in that: include: Supporting body; The displacement compensation device according to any one of claims 1 to 7, wherein one end of the displacement compensation device is connected to the supporting body.

9. A reactor, characterized in that: include: Pressure vessels; In the reactor internal equipment support described in claim 8, one end of the displacement compensation device is connected to the pressure vessel.

10. The reactor according to claim 9, characterized in that The pressure container comprises a connecting pipe, and the displacement compensation device is connected to the connecting pipe.

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