Combined supporting structure and dynamic constraint supporting system of nuclear power station

Abstract

A combined supporting structure comprises a first connecting rod, a second connecting rod and a damper, and the first end of the first connecting rod is hinged to a first civil engineering end; the first end of the second connecting rod is hinged to the equipment end, the second end of the second connecting rod is hinged to the second end of the first connecting rod, and the hinged position of the first connecting rod and the second connecting rod is movable. One end of the damper is hinged to the hinged position of the first connecting rod and the second connecting rod, and the other end of the damper is hinged to the second civil engineering end. The structure can be applied to specific occasions to solve the problem that the load and the stroke of the damper exceed limit values, and choices except for the damper and the check block are provided for model selection of dynamic constraint supporting in engineering design. According to the damper, free expansion of equipment under the thermal expansion working condition can be achieved, the stability of the equipment is kept under the earthquake working condition, the earthquake load borne by the damper can be greatly reduced, meanwhile, the tonnage, rigidity and stroke requirements of the damper can be reduced, the type selection process of the damper is simplified, and the purchase cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of nuclear power plant safety, and in particular to a combined support structure and a dynamic restraint support system for a nuclear power plant. Background Art

[0002] During the operation of a nuclear power plant, the high-temperature piping system and equipment will undergo large expansion displacements. To prevent the expansion of the system from causing damage to the equipment, a flexible design is required so that it can release the expansion displacement freely. However, in the event of accidental impact loads such as earthquakes, a rigid design is required so that the corresponding support can produce a rigid support effect. To resolve the above two contradictory requirements, two different forms of support, dampers and stop blocks, are generally used in the design of nuclear power plants, but both of these supports have certain shortcomings.

[0003] The damper is one of the important safety protection devices for nuclear power plant mechanical equipment. It is used to protect the nuclear power plant equipment and pipelines from damage when subjected to accidental impact loads such as earthquakes. It is installed between the equipment, pipelines and civil structures. When the equipment and pipelines are in normal working conditions, the damper can adapt to the slow movement of the equipment and pipelines due to thermal expansion and contraction, and has almost no restraining effect on the objects it supports. However, when subjected to situations such as earthquakes, water hammers, steam hammers, and safety valve exhaust, the damper becomes a rigid connection to limit displacement and protect the supported objects from damage due to accidental impact loads.

[0004] Large hydraulic dampers used in nuclear power plants have the following three shortcomings:

[0005] 1) Complex structure and extremely high cost. This type of support uses a hydraulic cylinder and a valve to achieve the function of releasing slow displacement and locking fast displacement. The internal structure is complex, the processing is difficult, and the cost is high.

[0006] 2) Too large, inconvenient to hoist and maintain. The damper must be able to withstand the dynamic load of the main equipment in earthquakes, water hammers, steam hammers, safety valve exhaust, etc., which are generally large loads, reaching hundreds or even thousands of tons. In order to withstand this load, the damper generally needs to be customized, resulting in an increase in cylinder diameter, thickness, and length, which ultimately makes processing, manufacturing, and identification difficult. Due to the sharp increase in support mass and volume, the mass can reach several tons, which poses a challenge to the installation space of the power plant and is not easy to hoist and repair.

[0007] 3) Insufficient support stiffness. When the equipment is subjected to dynamic impact, the damper needs to become a rigid connection to limit displacement and protect the supported equipment from damage due to accidental impact loads. Accordingly, the stiffness of the damper is required to be high. However, due to the limitations of the hydraulic system and components, the stiffness is less than that of a purely rigid tie rod of the same size, which increases the difficulty of seismic design of the equipment.

[0008] Use a support with a gap, with a gap between the support and the main equipment. This type of support is usually called a stopper. When the deformation of the main equipment exceeds the gap value, the stopper acts as a support. This type of support is also common in nuclear power plants. Under thermal expansion and internal pressure conditions, it does not affect the thermal expansion of the system and equipment, but under earthquake, pipeline rupture or swing conditions, when the deformation exceeds the gap value, it can limit the deformation of the equipment.

[0009] The stoppers used in nuclear power plants have the following two shortcomings:

[0010] 1) It is impossible to achieve a balance between expansion displacement and dynamic support effect. In order to protect the supported equipment from damage due to accidental impact loads under conditions of earthquake, pipeline rupture or swing, the support gap must be set small enough. Accordingly, the thermal expansion deformation of the equipment that can be absorbed by the support cannot exceed the gap. On the contrary, if the gap is increased, the free shaking deformation of the equipment will be too large under impact and vibration loads, which is not conducive to maintaining the stability of the equipment. This technology can only be used for equipment and pipeline systems with small thermal expansion displacement or directions with small expansion displacement in these equipment and pipeline systems, and has a small scope of application.

[0011] 2) Impact and vibration are generated after the gap is closed. The support stiffness is discontinuous. When the gap is not closed, the support stiffness of the equipment is zero. When the equipment shakes under dynamic load, causing the gap to close and contact, a sudden change in support stiffness will occur, which will produce an impact-like effect, causing excessive inertial response to the internal parts of the equipment and the connected auxiliary pipes and valves, which is not conducive to protecting the supported objects. Summary of the invention

[0012] In view of the shortcomings of the prior art mentioned above, the purpose of the present application is to provide a combined support structure and a dynamic constraint support system for a nuclear power plant, which is used to reduce the problems of high tonnage, stiffness, and stroke requirements of a single damper, difficulty in selection, and high cost in the existing single damper support scheme, as well as the problem of impact and flutter effects caused by the use of gap supports.

[0013] To achieve the above objectives and other related objectives, the present application provides a combined support structure, including:

[0014] a first connecting rod, wherein a first end of the first connecting rod is hinged to a first civil engineering end;

[0015] A second connecting rod, wherein a first end of the second connecting rod is hinged to the equipment end, a second end of the second connecting rod is hinged to the second end of the first connecting rod, and a hinged joint between the first connecting rod and the second connecting rod is movable;

[0016] A damper, one end of which is hinged to the hinge of the first connecting rod and the second connecting rod, and the other end of which is hinged to the second civil engineering end.

[0017] In an optional embodiment of the present application, the first connecting rod, the second connecting rod and the damper are connected at a common hinge using a pin structure.

[0018] In an optional embodiment of the present application, the damper is located in a region between the first civil engineering end and the equipment end.

[0019] In an optional embodiment of the present application, the damper is located outside the area between the first civil engineering end and the equipment end.

[0020] In an optional embodiment of the present application, the lengths of the first connecting rod and the second connecting rod are adjustable.

[0021] In an optional embodiment of the present application, the load borne by the damper is adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod.

[0022] In an optional embodiment of the present application, the optimal stroke of the damper is adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod.

[0023] In an optional embodiment of the present application, the sum of the lengths of the first connecting rod and the second connecting rod is greater than the distance between the first civil engineering end and the equipment end.

[0024] In an optional embodiment of the present application, the first connecting rod, the second connecting rod and the damper are in the same plane.

[0025] To achieve the above objectives and other related objectives, the present application also provides a nuclear power plant dynamic restraint support system, including:

[0026] Nuclear power plant equipment, wherein the nuclear power plant equipment is connected to the civil engineering by a combined support structure;

[0027] The combined support structure comprises:

[0028] a first connecting rod, wherein a first end of the first connecting rod is hinged to a first civil engineering end;

[0029] A second connecting rod, wherein a first end of the second connecting rod is hinged to the equipment end, a second end of the second connecting rod is hinged to the second end of the first connecting rod, and a hinged joint between the first connecting rod and the second connecting rod is movable;

[0030] A damper, one end of which is hinged to the hinge of the first connecting rod and the second connecting rod, and the other end of which is hinged to the second civil engineering end;

[0031] The first connecting rod, the second connecting rod and the damper are located in the same plane.

[0032] As described above, the combined support structure and the nuclear power plant dynamic restraint support system of the present application have the following beneficial effects:

[0033] The combined support structure of the present application is composed of a rigid connecting rod and a damper, and can be used in specific occasions to solve the problem of damper load and stroke exceeding the limit value, and provides an option other than dampers and stop blocks for the selection of dynamic constraint supports in engineering design. It can allow the equipment to expand freely under thermal expansion conditions and maintain the stability of the equipment under earthquake conditions, and can greatly reduce the seismic load borne by the damper. At the same time, it can also reduce the tonnage, stiffness requirements and stroke requirements of the damper, thereby simplifying the damper selection process and reducing procurement costs.

[0034] The combined support structure of the present application forms a combined support of a rigid connecting rod and a damper through the principle of force decomposition. By adjusting the length of the two rods, the load and tonnage requirements of the damper can be reduced. The damper tonnage can be reduced to 10% of the original design value in the single large damper support solution.

[0035] The combined support structure of the present application forms a combined support of a rigid link and a damper through the principle of triangular geometry, and the travel requirement of the damper can be reduced by adjusting the length of the two rigid links. The travel requirement of the damper can be reduced to 10% of the original design value in the single large damper support solution.

[0036] The stiffness required of the damper in the combined support structure of the present application is much smaller than the stiffness of the original single large damper.

[0037] The combined support structure of the present application forms a combined support of a rigid link and a damper through the principle of triangular geometry. The travel requirement of the damper can be reduced by adjusting the length of the two rigid links.

[0038] The combined support structure of the present application can adjust the lengths of the two rigid connecting rods according to design requirements, thereby flexibly arranging the installation position of the damper. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A first deployment structure diagram of the combined support structure provided in an embodiment of the present application;

[0040] Figure 2 A second deployment structure diagram of the combined support structure provided in the embodiment of the present application;

[0041] Figure 3 A third deployment structure diagram of the combined support structure provided in the embodiment of the present application;

[0042] Figure 4 An example diagram of hot and cold states of a first deployment structure of a combined support structure provided in an embodiment of the present application;

[0043] Figure 5 A simplified example diagram of hot and cold states of a first deployment structure of a combined support structure provided in an embodiment of the present application;

[0044] Figure 6 is the damper stroke coefficient curve;

[0045] Figure 7 This is an example diagram of the hot and cold states of the second deployment structure of the combined support structure provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0047] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application, and thus the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0048] In the following description, a lot of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0049] In order to solve the problems of high tonnage, stiffness, travel requirements, difficulty in selection and high cost of the damper in the existing single damper support solution of nuclear power plant mechanical equipment, as well as the problem of impact and flutter effects caused by gap support. The present application provides a nuclear power plant dynamic restraint support system, including nuclear power plant equipment and such Figure 1-3 The combined supporting structure shown, the nuclear power plant equipment is connected with the civil engineering by using the combined supporting structure.

[0050] like Figure 1-Figure 3As shown, the combined support structure is mainly composed of three parts: a first connecting rod (rod 1), a second connecting rod (rod 2) and a damper. Among them, the first end of the first connecting rod is hinged to the first civil engineering end (civil engineering 1); the first end of the second connecting rod is hinged to the equipment end, the second end of the second connecting rod is hinged to the second end of the first connecting rod, and the hinge between the first connecting rod and the second connecting rod is movable; one end of the damper is hinged to the hinge B between the first connecting rod and the second connecting rod, and the other end of the damper is hinged to the second civil engineering end (civil engineering 2). The combined support structure of the present application can adapt to the situation that the expansion direction of the nuclear power plant equipment is parallel to the line connecting the first civil engineering end and the equipment end; it can also adapt to the situation that the expansion direction of the nuclear power plant equipment forms a non-zero angle with the line connecting the first civil engineering end and the equipment end.

[0051] In the present application, the first connecting rod and the second connecting rod are composed of a rigid connecting rod. A rigid connecting rod refers to a rod whose axial deformation is less than a preset deformation value when subjected to a preset axial tensile and compressive load value. The preset axial compressive load value and the preset deformation value need to be set according to the actual application scenario of the project.

[0052] In the present application, the lengths of the first connecting rod and the second connecting rod are adjustable. The load borne by the damper can be adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod. The optimal stroke of the damper can be adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod.

[0053] In the present application, in practical applications, it is necessary to keep the axes of the first connecting rod, the second connecting rod and the damper in the same plane. This design can ensure the uniformity of force, avoid local stress concentration caused by misalignment or imbalance, and improve the overall stability of the structure. On the other hand, it can also effectively reduce the friction and wear caused by misalignment, extend the service life of the damper and the connecting rod, and at the same time, it can also improve the response speed of the system under dynamic loading conditions, so that the structure can absorb and dissipate energy faster when subjected to external excitation, thereby improving the performance of the combined support structure and ensuring the reliability and effectiveness of the combined support structure in practical applications.

[0054] In the present application, in order to keep the axes of the first connecting rod, the second connecting rod and the damper in the same plane, the common hinge B of the first connecting rod, the second connecting rod and the damper can be connected by a pin structure, thereby limiting the free movement of the hinge position in the vertical direction.

[0055] In this application, the damper can be based on the actual situation of the plant. Figure 1 As shown, it is arranged in the area between the first civil engineering end and the equipment end, and can also be arranged as shown in FIG. Figure 2 and Figure 3 As shown, it is arranged outside the area between the first civil engineering end and the equipment end, and the installation position is more flexible.

[0056] In the present application, it is necessary to ensure that the first connecting rod and the second connecting rod are not collinear during the hot and cold state switching of the equipment, so as to avoid the jamming phenomenon. To this end, it is necessary to ensure that during the hot and cold state switching, the sum of the lengths of the first connecting rod and the second connecting rod is greater than the distance between the first civil engineering end and the equipment end.

[0057] It should be noted that when the damper is arranged in the area between the first civil engineering end and the equipment end, in order to minimize the seismic load borne by the damper, the length of the first connecting rod and the second connecting rod may be slightly larger than the distance between the first civil engineering end and the equipment end. For example, the difference between the length of the first connecting rod and the second connecting rod and the distance between the first civil engineering end and the equipment end needs to be greater than 0 mm and less than or equal to 30 mm, for example, 10 mm, 20 mm, 30 mm.

[0058] The combined support structure of the present application can be used in specific occasions to solve the problem of damper load and stroke exceeding the limit value, and provides an option other than dampers and blocks for the selection of dynamic constraint supports in engineering design. It can allow the equipment to expand freely under thermal expansion conditions and maintain the stability of the equipment under earthquake conditions, and can greatly reduce the seismic load borne by the damper. At the same time, it can also reduce the tonnage, stiffness requirements and stroke requirements of the damper, thereby simplifying the damper selection process and reducing procurement costs.

[0059] The combined support structure of the present application forms a combined support of a rigid connecting rod and a damper through the principle of force decomposition. By adjusting the length of the two rods, the load and tonnage requirements of the damper can be reduced. The damper tonnage can be reduced to 10% of the original design value in the single large damper support solution.

[0060] The combined support structure of this embodiment forms a combined support of a rigid connecting rod and a damper through the principle of triangular geometry. By adjusting the length of the two rods, the stroke requirement of the damper can be reduced. The stroke requirement of the damper can be reduced to 10% of the original design value in the single large damper support solution.

[0061] The stiffness required of the damper in the combined support structure of the present application is much smaller than the stiffness required of the damper in the original single large damper support solution.

[0062] The combined support structure of the present application can adjust the lengths of the two rigid connecting rods according to design requirements, thereby flexibly arranging the installation position of the damper. The combined support structure of the present application will be described in detail below in conjunction with three specific embodiments.

[0063] Example 1

[0064] like Figure 1 As shown, in this embodiment, the damper is located in the area between the first civil engineering end and the equipment end, and the expansion direction of the equipment is parallel to the line connecting point A and point C. Figure 1 In the figure, the black solid line is a schematic diagram of the positions of the components, equipment and civil engineering in the combined support structure in the cold state; the red dotted line is a schematic diagram of the positions of the components in the combined support structure in the hot state. In the case of thermal expansion, the damper does not limit the displacement, that is, BD can be freely extended and retracted, because the first connecting rod and the equipment, the first connecting rod and the second connecting rod, and the second connecting rod and the civil engineering are hinged, so the equipment can be freely expanded from point C to point C'.

[0065] It should be noted that Figure 1 The hot and cold positions in the figure are based on the case where the equipment is thermally expanded toward the first civil engineering end (point A). If the equipment is thermally expanded away from point A, the hot and cold positions in the figure can be swapped.

[0066] The mechanical principle of the combined support component of this embodiment is explained.

[0067] Figure 4 One is the situation where the equipment expands in the direction of the civil engineering end (point A); the other is the situation where the equipment expands in the opposite direction of the civil engineering end (point A), that is, Figure 4 The cold and hot positions in the equation are interchanged. Assuming that the hot displacement is along the AC direction, we simplify the equation by assuming that AC' and AC are in a straight line, i.e. L3 = Ld.

[0068] Define the following parameters:

[0069] The length of the first connecting rod L1 = BC = B′C′;

[0070] The second connecting rod length L2 = AB = AB';

[0071] The cold distance between civil engineering and equipment is L = AC;

[0072] The thermal distance between civil engineering and equipment is L3 = AC';

[0073] Equipment thermal displacement d = CC';

[0074] The height corresponding to side AC of ΔABC is h1;

[0075] The height corresponding to the side AC' of ΔAB'C' is h2;

[0076] The damper's hot and cold stroke (referred to as stroke) h;

[0077] Original support load F;

[0078] Original support stiffness K;

[0079] Damper load f;

[0080] Damper stiffness k.

[0081] 1.1 The damper stroke is derived as follows:

[0082] 1.1.1 Thermal expansion of equipment towards the civil engineering end (point A)

[0083] In order to simplify the analysis, it is assumed that in the cold state, the first connecting rod and the second connecting rod are just straightened, that is, AB and AC are in a straight line, L2+L1=L, h1=0 (in actual application, L2+L1 should be slightly larger than L, such as 10mm, otherwise it is easy to get stuck in the cold state). The cold and hot states of the combined support structure of this embodiment are shown as follows: Figure 5 .

[0084] According to Heron's formula, the area of ​​a triangle with sides a, b, and c is

[0085] in,

[0086] Correspondingly, the height corresponding to the c side

[0087] Here a=L1, b=L2, c=L2+L1-d.

[0088] so,

[0089] Assume that L1 = γL, then L2 = (1-γ)L,

[0090]

[0091] Assuming L = AC ≤ 3200 mm, d = 60 mm, L is much larger than d, ignoring d which has an algebraic sum (or subtraction) relationship with L in the formula, these formulas can be simplified to:

[0092]

[0093] From formula (3), we can see that:

[0094] The longer L is, the larger h is; the longer d is, the larger h is; when L and d are fixed, the value of h is In a linear relationship. Figure 6 As shown, γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the smaller h is. When γ = 0.5 (the two connecting rods are of equal length), the value is the largest. That is, the shorter the first connecting rod or the second connecting rod is, the shorter the stroke of the damper is; at the same time, the first connecting rod or the second connecting rod cannot be infinitely short. In engineering applications, it can be assumed that the length of the first connecting rod or the second connecting rod is fixed to 300 mm.

[0095] 1.1.2 The equipment expands in the opposite direction to the civil engineering end (point A)

[0096] Compared with the thermal expansion of the equipment toward the civil engineering end (point A), it is just the exchange of hot and cold states. Based on the similar derivation process of 1.1.1, the hot and cold state travel of the damper can be expressed by the following formula:

[0097]

[0098] Therefore, the longer L is, the larger h is; the longer d is, the larger h is; when L and d are determined, the value of h is In a linear relationship. Figure 6 As shown, γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the smaller h is. When γ = 0.5 (the two connecting rods are of equal length), the value is the largest. That is, the shorter the first connecting rod or the second connecting rod is, the shorter the stroke of the damper is; at the same time, the first connecting rod or the second connecting rod cannot be infinitely short. In engineering applications, it can be assumed that the length of the first connecting rod or the second connecting rod is fixed to 300 mm.

[0099] 1.2 The damper load is derived as follows:

[0100] In dynamic situations, the damper load is related to the displacement, velocity, and acceleration of the system, which is different from the static equation (i.e., only the displacement term). To simplify the derivation process, the damper load is calculated based on the equivalent static force and the assumption that the damper is infinitely rigid.

[0101] 1.2.1 Thermal expansion of equipment towards the civil engineering end (point A)

[0102] Original support, stiffness K, load F, then the displacement of the equipment end point is

[0103] In the combined support scheme of this embodiment, the stiffness k of the damper, the load f of the damper, and the displacement (Y direction) of the damper are:

[0104] In static state, the damper load

[0105] Assume that, under the load, the original equipment support stiffness is large enough and the end displacement Much smaller than d, ignore The displacement stiffness of the damper of the combined support scheme is large enough. Much smaller than h, ignore but

[0106] Assume that L1 = γL, then L2 = (1-γ)L,

[0107]

[0108] Ignoring d which has an algebraic relationship with L, we can

[0109]

[0110] Therefore, the longer L is, the smaller f is; the longer d is, the larger f is; when L and d are fixed, the value of f is In an inverse relationship. γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the larger f is. When γ = 0.5 (the two rods are of equal length), the f value is the smallest. That is, the shorter the first link or the second link, the greater the load on the damper.

[0111] 1.2.2 The equipment expands in the opposite direction to the civil engineering end (point A)

[0112] Damper Load

[0113] Therefore, the longer L is, the smaller f is; the smaller h1 is, the smaller f is. When L and h1 are determined, the value of f is inversely proportional to γ(1-γ). γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the larger f is. When γ=0.5 (the two rods are of equal length), the value of f is the smallest. That is, the shorter the first link or the second link is, the greater the load on the damper.

[0114] 1.3 The damper stiffness is derived as follows:

[0115] The equivalent stiffness of the combined support scheme of this embodiment is equal to the stiffness of the original support, so the combined support scheme can achieve the effect of the original support. In order to simplify the calculation, it is assumed that the first connecting rod and the second connecting rod are infinitely stiff.

[0116] Original support, stiffness K, load F, then the displacement of the equipment end point is

[0117] In the combined support scheme of this application, the stiffness k of the damper, the load f of the damper, and the displacement (Y direction) of the damper are:

[0118] 1.3.1 Thermal expansion of equipment towards the civil engineering end (point A)

[0119] Replace h in formula (3) with Replace; d with replace

[0120]

[0121] in,

[0122] therefore,

[0124] Therefore, k is in an inverse relationship with L. The longer L is, the smaller k is. k is in an inverse relationship with γ(1-γ). γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the larger k is. When γ=0.5 (the two rods are of equal length), the k value is the smallest. That is, the shorter the first link is, the greater the stiffness of the damper is.

[0125] 1.3.2 The equipment expands in the opposite direction to the civil engineering end (point A)

[0126] Replace h in formula (3) with Replace; d with Instead, the simplified formula is as follows:

[0127]

[0128] in,

[0129] Damper Load therefore,

[0130]

[0131] Therefore, k and √L are inversely related. The longer L is, the smaller k is. In an inverse relationship. γ(1-γ) is a parabola. The closer γ is to 0 or 1, the smaller γ(1-γ), that is, the larger k is. When γ = 0.5 (the two rods are of equal length), the value of γ(1-γ) is the largest and the value of k is the smallest. That is, the shorter the first link or the second link, the greater the stiffness of the damper.

[0132] The above derivation process can be summarized as shown in Table 1 and Table 2:

[0133] Table 1 Thermal expansion of equipment towards the civil engineering end (point A)

[0134]

[0135]

[0136] Table 2, thermal expansion of equipment in the opposite direction to the civil engineering end (point A)

[0137]

[0138] Substituting the data of a certain equipment in a nuclear power plant shown in Table 3 into formula (2) and formula (3), the stroke and load of the damper under different cold distances between the civil engineering and the equipment are calculated, as shown in Table 4.

[0139] Table 3 Parameters of damper of a certain equipment in nuclear power plant

[0140] Original support bearing F(tons) 850 Equipment thermal displacement d(mm) 60 First connecting rod length L1(mm) 300 (assumption)

[0141] Table 4 Damper stroke and load at different cold spacings

[0142] Cold distance between civil engineering and equipment Damper travel Damper Load L(mm) h(mm) f(t) 1000 154.37 279.18 1200 159.30 237.56 1400 162.64 206.33 1600 165.05 182.19 1800 166.87 163.03 2000 168.29 147.47 2200 169.44 134.60 2400 170.38 123.78 2600 171.17 114.56 2800 171.83 106.61 3000 172.41 99.69 3200 172.91 93.61

[0143] Most of the damper strokes in the table above are between 160 and 170 mm. Considering the damper stroke under earthquake load (estimated to be no more than 10 mm), the total stroke is still less than 180 mm, and there are mature dampers to choose from. The damper load in the table above is much smaller than the original support load, and the damper tonnage reduction effect is obvious.

[0144] The first connecting rod is stressed Pull the second connecting rod Both are smaller than F, so the solution is feasible.

[0145] In terms of stiffness, assuming that the first link and the second link are infinitely rigid, the stiffness requirement for the damper is K is the original support stiffness. From the above table, we can see that the damper stiffness requirement is about 1 / 10 of the original support stiffness (when L is about 1800mm), and the solution is feasible.

[0146] Therefore, the combined support structure of this embodiment can achieve free expansion of the equipment under thermal expansion conditions, maintain the stability of the equipment under earthquake conditions, and can greatly reduce the seismic load borne by the damper. The damper tonnage can be reduced to 10% of the original design value. Under the limit state (two connecting rods are collinear), the damper does not bear the seismic load. The stiffness required by the damper in the combined support is much smaller than the stiffness of the original single large damper, which can be reduced to 10% of the original design value. At the same time, the stroke required by the damper in the combined support is smaller, and the damper selection is easier. This structure can be applied to specific occasions to solve the problem of damper load and stroke exceeding the limit value, and provides an option other than dampers and blocks for the selection of dynamic constraint supports in engineering design.

[0147] Example 2

[0148] like Figure 2 As shown, in this embodiment, the damper is located outside the area between the first civil engineering end and the equipment end, and the expansion direction of the equipment is parallel to the line connecting point A and point C. Figure 2 In the figure, the black solid line is a schematic diagram of the positions of the components, equipment and civil engineering in the combined support structure in the cold state; the red dotted line is a schematic diagram of the positions of the components in the combined support structure in the hot state. In the case of thermal expansion, the damper does not limit the displacement, that is, BD can be freely extended and retracted, because the first connecting rod and the equipment, the first connecting rod and the second connecting rod, and the second connecting rod and the civil engineering are hinged, so the equipment can be freely expanded from point C to point C'. Compared with the solution of Example 1, the travel requirement of the damper is reduced more significantly.

[0149] It should be noted that Figure 2 The hot and cold positions in the figure are based on the case where the equipment is thermally expanded toward the first civil engineering end (point A). If the equipment is thermally expanded away from point A, the hot and cold positions in the figure can be swapped.

[0150] The mechanical principle of the combined support component of this embodiment is explained.

[0151] Figure 7 One is the situation where the equipment expands in the direction of the civil engineering end (point A); the other is the situation where the equipment expands in the opposite direction of the civil engineering end (point A), that is, Figure 7 The cold and hot positions in the equation are interchanged. Assuming that the hot displacement is along the AC direction, we simplify the equation by assuming that AC' and AC are in a straight line, i.e. L3 = Ld.

[0152] Define the following parameters:

[0153] The length of the first connecting rod L1 = BC = B′C′;

[0154] The second connecting rod length L2 = AB = AB';

[0155] The cold distance between civil engineering and equipment is L = AC;

[0156] The thermal distance between civil engineering and equipment is L3 = AC';

[0157] Equipment thermal displacement d = CC';

[0158] The height corresponding to side AC of ΔABC is h1;

[0159] The height corresponding to the side AC' of ΔAB'C' is h2;

[0160] The damper's hot and cold stroke (referred to as stroke) h = h1-h2;

[0161] Original support load F;

[0162] Original support stiffness K;

[0163] Damper load f;

[0164] Damper stiffness k.

[0165] According to Heron's formula,

[0166] in,

[0167] Correspondingly, the height corresponding to the c side

[0168] Triangle ABC,

[0169] a=L1

[0170] b=L2

[0171] c=L

[0172] but,

[0173] Triangle AB'C',

[0174] a'=L1

[0175] b'=L2

[0176] c'=Ld

[0177] but,

[0178] Ignoring the damper deformation (under a more reasonable solution, the impact is about 10%), the damper load is:

[0179]

[0180] Therefore, the larger L1 is, the smaller f is; the smaller h2 is, the smaller f is. Therefore, h2 should be as small as possible. In practical applications, h2 cannot be infinitely small to avoid collision between the second link and the first link or equipment, for example, h2 = 200 mm.

[0181] When L, d, and h2 are all determined,

[0182] According to the Pythagorean theorem,

[0183] The larger L1 is, the larger L2 is.

[0184] Taking the data of a certain equipment in a nuclear power plant shown in Table 5 as an example, the corresponding data of the second connecting rod length, damper stroke, and cold height when the length L1 of the first connecting rod takes different values ​​can be calculated, as shown in Table 6.

[0185] Table 5 Parameters of damper of a certain equipment in nuclear power plant

[0186] Original support bearing F(t) 850 Equipment thermal displacement d(mm) 60 Cold distance between civil engineering and equipment L(mm) 3200 (maximum value) Hot height h2(mm) 200

[0187] Table 6 Second connecting rod length, damper stroke, and cold height data of the combined support structure of Example 2 at different L1

[0188]

[0189] It can be seen from this that the solution of Example 2 can greatly reduce the damper stroke requirement.

[0190] Example 3

[0191] like Figure 3 As shown, in this embodiment, the damper is located outside the area between the first civil engineering end and the equipment end, and the expansion direction of the equipment forms a non-zero angle with the line connecting point A and point C. Figure 3 In the figure, the black solid line is a schematic diagram of the positions of the components, equipment and civil engineering in the combined support structure in the cold state; the red dotted line is a schematic diagram of the positions of the components in the combined support structure in the hot state. In the case of thermal expansion, the damper does not limit the displacement, that is, BD can be freely extended and retracted, because the first connecting rod and the equipment, the first connecting rod and the second connecting rod, and the second connecting rod and the civil engineering are hinged, so the equipment can be freely expanded from point C to point C'.

[0192] The effects of this embodiment are similar to those of embodiment 2, so no further description will be given. The mechanical principle of the combined support component of this embodiment is the same as that of embodiment 2, and can be deduced according to actual parameters by referring to the above process.

[0193] In summary, the combined support structure disclosed in the present application is composed of a rigid connecting rod and a damper, which can be applied to specific occasions to solve the problem of damper load and stroke exceeding the limit value, and provides an option other than dampers and blocks for the selection of dynamic constraint supports in engineering design. It can not only realize the free expansion of the equipment under thermal expansion conditions, but also maintain the stability of the equipment under earthquake conditions, and can greatly reduce the seismic load borne by the damper. At the same time, it can also reduce the tonnage, stiffness requirements and stroke requirements of the damper, thereby simplifying the selection process of the damper and reducing procurement costs. The combined support structure of the present application forms a combined support of a rigid connecting rod and a damper through the principle of force decomposition. By adjusting the length of the two rods, the load and tonnage requirements of the damper can be reduced. The damper tonnage can be reduced to 10% of the original design value in the single large damper support solution. The stiffness required by the damper in the combined support structure of the present application is much smaller than the stiffness of the original single large damper. The combined support structure of the present application forms a combined support of a rigid connecting rod and a damper through the principle of triangular geometry. By adjusting the length of the two rods, the stroke requirement of the damper can be reduced to 10% of the original design value in the single large damper support solution. The combined support structure of the present application can adjust the length of the two rigid connecting rods according to the design requirements, so as to flexibly arrange the installation position of the damper. Therefore, the present application effectively overcomes various shortcomings in the prior art and has a high industrial utilization value.

[0194] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A combined support structure, characterized in that: include: a first connecting rod, wherein a first end of the first connecting rod is hinged to a first civil engineering end; A second connecting rod, wherein a first end of the second connecting rod is hinged to the equipment end, a second end of the second connecting rod is hinged to the second end of the first connecting rod, and a hinged joint between the first connecting rod and the second connecting rod is movable; A damper, one end of which is hinged to the hinge of the first connecting rod and the second connecting rod, and the other end of which is hinged to the second civil engineering end.

2. The combined support structure according to claim 1, characterized in that: The first connecting rod, the second connecting rod and the damper are connected at a common hinge point by a pin structure.

3. The combined support structure according to claim 1, characterized in that: The damper is located in a region between the first civil end and the equipment end.

4. The combined support structure according to claim 1, characterized in that: The damper is located outside the area between the first civil end and the equipment end.

5. The combined support structure according to claim 1, characterized in that: The lengths of the first connecting rod and the second connecting rod are adjustable.

6. The combined support structure according to claim 1, characterized in that: The load borne by the damper is adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod.

7. The combined support structure according to claim 1, characterized in that: The optimal stroke of the damper is adjusted by adjusting the length ratio of the first connecting rod and the second connecting rod.

8. The combined support structure according to claim 1, characterized in that: The sum of the lengths of the first connecting rod and the second connecting rod is greater than the distance between the first civil engineering end and the equipment end.

9. The combined support structure according to claim 1, characterized in that: The first connecting rod, the second connecting rod and the damper are located in the same plane.

10. A dynamic restraint support system for a nuclear power plant, characterized in that: include: Nuclear power plant equipment, wherein the nuclear power plant equipment is connected to the civil engineering by a combined support structure; The combined support structure comprises: a first connecting rod, wherein a first end of the first connecting rod is hinged to a first civil engineering end; A second connecting rod, wherein a first end of the second connecting rod is hinged to the equipment end, a second end of the second connecting rod is hinged to the second end of the first connecting rod, and a hinged joint between the first connecting rod and the second connecting rod is movable; A damper, one end of which is hinged to the hinge of the first connecting rod and the second connecting rod, and the other end of which is hinged to the second civil engineering end; The first connecting rod, the second connecting rod and the damper are located in the same plane.

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