Pipe assembly and coolant pipe system

Abstract

The invention discloses a pipeline assembly and a coolant pipeline system.The pipeline assembly comprises a main pipeline, a restraining pipe fitting and a branch pipe, the restraining assembly comprises a barrel and a plurality of restraining parts, the restraining parts are arranged in the barrel, and a plurality of restraining cavities arranged side by side in the radial direction of the barrel are defined between the adjacent restraining parts and / or between the restraining parts and the barrel; the two ends of the restraining pipe fitting are connected to the main pipeline and the branch pipe. The restraining pipe fitting is arranged between the main pipeline and the branch pipe, when high-temperature and high-speed fluid in the main pipeline flows into the restraining pipe fitting, vortexes formed by the fluid are damaged by the restraining part, are distributed into the different restraining cavities and then flow into the branch pipe in the extending direction of the restraining cavities under the guidance of the restraining cavities, and by arranging the restraining pipe fitting, the flowing speed of the fluid is increased. Turbulent flow permeation of fluid can be restrained and eliminated fundamentally, thermal stratification in the branch pipe can be relieved or eliminated, and then the probability that thermal stress or thermal fatigue effect occurs in the pipeline is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power pipeline systems, and in particular to a pipeline system, namely a coolant pipeline system. Background Art

[0002] When the high-temperature fluid in the main pipe flows through the branch pipe in a stagnant state, due to the high flow rate of the fluid in the main pipe, the fluid generates a high-speed vortex in the branch pipe. Driven by the inertia of the water body, the vortex develops toward the closed end of the branch pipe and transfers the heat in the main pipe to the branch pipe, thereby causing temperature stratification in the branch pipe. When thermal stratification occurs in the horizontal pipe and is superimposed on temperature fluctuations, it will cause thermal stress and thermal fatigue to the system pipes, thereby creating the risk of cracks and even leakage in the pipes. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a pipeline assembly that can reduce the probability of thermal stratification in branch pipes and reduce the probability of thermal stress and thermal fatigue in the pipelines.

[0004] The present invention also provides a coolant piping system having the piping assembly.

[0005] A pipeline assembly according to an embodiment of the first aspect of the present invention comprises:

[0006] Main road;

[0007] A restraining pipe, comprising a cylinder and a plurality of restraining portions, wherein the restraining portions extend along the length direction of the cylinder and are arranged inside the cylinder, and a plurality of restraining cavities arranged side by side along the radial direction of the cylinder are defined between adjacent restraining portions and / or between the restraining portions and the cylinder;

[0008] The branch pipe has two ends connected to the main pipe and the branch pipe, and the branch pipe is communicated with the main pipe along the radial direction of the main pipe through the constraint cavity.

[0009] The pipeline assembly according to the embodiment of the present invention has at least the following beneficial effects:

[0010] In an embodiment of the present invention, a constraint pipe fitting is provided between the main pipe and the branch pipe. When the high-temperature, high-speed fluid in the main pipe flows into the constraint pipe fitting, the vortex formed by the fluid is destroyed by the constraint portion and diverted to different constraint cavities. Then, guided by the constraint cavity, the fluid flows into the branch pipe along the extension direction of the constraint cavity. By providing the constraint pipe fitting, the turbulent penetration of the fluid can be curbed and eliminated at the source, and the thermal stratification in the branch pipe can be alleviated or eliminated, thereby reducing the probability of thermal stress or thermal fatigue effects in the pipeline.

[0011] According to some embodiments of the present invention, the length of the restraining pipe is L1, the nominal diameter of the restraining pipe is D, and 2D≤L1≤5D.

[0012] According to some embodiments of the present invention, the thickness of the constraint portion is T1, the wall thickness of the cylinder is T2, and 0.5T2≤T1≤T2.

[0013] According to some embodiments of the present invention, the pipeline assembly further includes a connecting pipe fitting, two ends of which are respectively connected to the main pipe and the restraining pipe fitting.

[0014] According to some embodiments of the present invention, the restraining portion protrudes toward one end of the main pipe to the outside of the cylinder and is inserted into the connecting pipe.

[0015] According to some embodiments of the present invention, the length of the connecting pipe is L2, the length of the restraining pipe is L1, and 0<L2≤0.5L1.

[0016] According to some embodiments of the present invention, the inner diameter of the connecting pipe gradually decreases in a direction toward the restraining pipe, and the outer diameter of one end of the connecting pipe facing the restraining pipe is the same as the outer diameter of the restraining pipe;

[0017] Alternatively, the nominal diameter of the connecting pipe is the same as the nominal diameter of the restraining pipe.

[0018] According to some embodiments of the present invention, one end of the connecting pipe is integrally connected to the main pipe, and the other end is welded to the restraining pipe;

[0019] Alternatively, one end of the connecting pipe is welded to the main pipe, and the other end is welded to the restraining pipe.

[0020] According to some embodiments of the present invention, the restraining pipe is an integrally formed structure.

[0021] According to some embodiments of the present invention, one side of a plurality of the constraint portions is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder, and the other opposite sides of each of the constraint portions are butted against each other, and adjacent constraint portions and the inner wall of the cylinder define the constraint cavity;

[0022] Alternatively, one side of a plurality of the constraint portions is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder, and the other side opposite to each constraint portion is connected to the side of an adjacent constraint portion, and the constraint cavity is defined between adjacent constraint portions and the inner wall of the cylinder and between all the constraint portions;

[0023] Alternatively, a plurality of the restraining portions are connected end to end, and the connection points of adjacent restraining portions are all connected to the inner wall of the cylinder, and the restraining cavity is defined between the restraining portion and the inner wall of the cylinder and between all the restraining portions.

[0024] According to some embodiments of the present invention, the constraint tube further includes a center column, which is located inside the cylinder, and the constraint portion is located between the center column and the inner wall of the cylinder. One side of a plurality of the constraint portions is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder, and the other side of the plurality of the constraint portions is connected to the circumferential side of the center column. The adjacent constraint portions, the circumferential side of the center column and the inner wall of the cylinder define the constraint cavity.

[0025] According to some embodiments of the present invention, the radial center of the central column coincides with the radial center of the cylinder.

[0026] According to some embodiments of the present invention, a central cavity is provided inside the central column.

[0027] According to some embodiments of the present invention, the restraining portions are arranged at equal intervals around the inner wall of the cylinder;

[0028] And / or, the included angles between adjacent constraint portions are equal.

[0029] A coolant piping system according to an embodiment of a second aspect of the present invention includes:

[0030] The pipeline assembly of the first aspect embodiment;

[0031] A coolant pipeline is connected to one end of the main pipeline.

[0032] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0034] Figure 1 is a schematic diagram of an embodiment of a pipeline assembly of the present invention;

[0035] Figure 2 A three-dimensional schematic diagram of an embodiment of a restraining pipe fitting;

[0036] Figure 3 This is the velocity distribution diagram of the fluid in the lower part of the branch pipe before the restraining pipe fittings are installed;

[0037] Figure 4 This is the velocity distribution diagram of the fluid in the lower part of the branch pipe after the constraint fitting is set;

[0038] Figure 5 A schematic diagram of the distribution of an embodiment of a restraining portion within a restraining pipe;

[0039] Figure 6 To constrain the department Figure 5 A comparison of the pressure differences between the upper and lower ends of the branch pipe after different embodiments are set up as shown in FIG;

[0040] Figure 7 Schematic diagram of the distribution of other embodiments of the restraining portion within the restraining pipe;

[0041] Figure 8 Schematic diagram of the distribution of other embodiments of the restraining portion within the restraining pipe;

[0042] Figure 9 Schematic diagram of the distribution of other embodiments of the restraining portion within the restraining pipe;

[0043] Figure 10 Schematic diagram of the distribution of other embodiments of the restraining portion within the restraining pipe;

[0044] Figure 11 FIG. 1 is a schematic diagram of an embodiment of a coolant piping system according to the present invention.

[0045] Reference numerals:

[0046] Pipe assembly 100, main line 110, restraining pipe 120, cylinder 121, restraining portion 122, restraining cavity 123, center column 124, center cavity 125, branch pipe 130, vertical section 131, horizontal section 132, connecting pipe 140; coolant pipe 200; connecting pipe 300; heat exchanger 400; drive pump 500; valve 600. DETAILED DESCRIPTION

[0047] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0048] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0049] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0050] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0051] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0052] When the high-temperature fluid in the main pipe flows through a branch pipe in a stagnant state, the fluid generates high-speed vortices in the branch pipe due to the high flow velocity of the fluid in the main pipe. Taking the branch pipe connected to the reactor coolant system in a pressurized water reactor nuclear power plant as an example, one end of the branch pipe is connected to the main pipe of the reactor coolant system and is disturbed by the high-temperature, high-speed fluid. The other end is usually in a stagnant state due to long-term closure. Because the flow velocity in the main pipe of the reactor coolant system is relatively high, usually greater than 10m / s, when the high-temperature, high-speed fluid flows into the branch pipe, a high-speed vortex is generated in the branch pipe. Driven by the inertia of the water body, the vortex continues to develop toward the closed end of the branch pipe, thereby transferring the heat from the branch pipe to the branch pipe and triggering a series of thermal hydraulic phenomena. For example, under certain operating conditions, natural convection is generated in the branch pipe and temperature stratification (thermal stratification) is formed. When thermal stratification occurs in the lateral part of the branch pipe and is superimposed on the temperature fluctuations caused by turbulent penetration, it will cause thermal stress and thermal fatigue to the entire reactor coolant system, causing cracks in the pipeline and even leakage risks, posing a threat to the safety of the nuclear power plant.

[0053] Based on this, an embodiment of the present invention provides a pipeline assembly 100 for reducing the probability of thermal stratification in the branch pipe 130 and the probability of thermal stress and thermal fatigue in the pipeline. Figure 1 and Figure 2The pipeline assembly 100 includes a main line 110, a restraining pipe 120 and a branch pipe 130. The main line 110 can be used as the main circulation line in the system and should circulate the main fluid of the system, such as reactor coolant. The branch pipe 130 is a branch of the main line 110 in the system and is used to divert and discharge the main fluid.

[0054] Branch pipe 130 communicates with main pipe 110 via constraint fitting 120, which includes a barrel 121 and multiple constraint portions 122. Barrel 121 is hollow, with its inner cavity extending along the direction of barrel 121. The ends of barrel 121 are connected to main pipe 110 and branch pipe 130, respectively. Fluid in main pipe 110 flows into branch pipe 130 through the inner cavity of barrel 121. Constraint portions 122 are disposed within barrel 121 and extend along the length of barrel 121. Adjacent constraint portions 122 and the spaces between them and the inner wall of barrel 121 define multiple constraint cavities 123, which are arranged side by side along the radial direction of barrel 121. The branch pipe 130 is connected to the main line 110 along the radial direction of the main line 110 through the constraint cavity 123, that is, the constraint pipe 120 is connected to one side of the radial direction of the main line 110, and the extension direction of the constraint cavity 123 has an angle with the extension direction of the main line 110. In some embodiments, the extension direction of the constraint cavity 123 can be set to be perpendicular to the extension direction of the main line 110, for example, the main line 110 extends in the horizontal direction and the constraint cavity 123 extends in the vertical direction.

[0055] The applicant has studied the thermal stratification, thermal cycle and thermal shock in the branch pipe 130 and found that the turbulent penetration of the fluid in the main line 110 in the branch pipe 130 is the main reason for the formation of thermal stratification. Therefore, a constraint pipe 120 is set between the main line 110 and the branch pipe 130. When the high-temperature and high-speed fluid in the main line 110 flows into the constraint pipe 120, the vortex formed by the fluid is destroyed by the constraint part 122 and diverted to different constraint chambers 123. Then, guided by the constraint chamber 123, the fluid flows along the constraint chamber 123. The fluid flows into the branch pipe 130 in the extension direction; in this way, by setting the restraining pipe 120, the turbulent penetration of the fluid can be curbed and eliminated at the root, and the thermal stratification in the branch pipe 130 can be alleviated or eliminated, thereby reducing the probability of thermal stress or thermal fatigue effects in the pipeline, providing a guarantee for the safe operation of the nuclear power plant and the prevention of radioactive release; and, for nuclear power plants in service, it is only necessary to set the restraining pipe 120 between the main line 110 and the branch pipe 130 to eliminate thermal stratification, which is easy to operate, has low modification cost and high reliability.

[0056] Reference Figure 3 and Figure 4 , Figure 3 This is the velocity distribution diagram of the fluid in the lower part of the branch pipe 130 before the constraint pipe 120 is set. Figure 4The velocity distribution diagram of the fluid in the lower part of the branch pipe 130 after the constraint pipe 120 is set. Figure 3 It can be seen that before the restraining pipe 120 is set, turbulence occurs at Figure 3 In the fault area of ​​the middle branch pipe 130, where the turbulence occurs, the fluid velocity in the branch pipe 130 drops suddenly and shows obvious stratification. The temperature fluctuation caused by the turbulence penetration in the stratified area causes cracks and penetration in the pipe. Figure 4 It can be seen that after the constraint pipe 120 is installed, the turbulence is destroyed and constrained by the constraint portion 122 in the constraint pipe 120, and the flow velocity of the fluid in the branch pipe 130 gradually decreases and drops to zero at the lower end of the branch pipe 130. It can be seen that the turbulent penetration is curbed, and the heat of the main line 110 is terminated at the lower end of the branch pipe 130 and cannot continue to be transferred to other areas of the branch pipe 130 (such as the lateral part), so it will not cause natural convection and thermal stratification in other areas, thereby eliminating thermal stress and thermal fatigue of the pipeline.

[0057] like Figure 1 As shown, main line 110 extends horizontally, while the upper end of restraining pipe 120 is connected to a radial side of main line 110 and extends vertically. The lower end of restraining pipe 120 is connected to the upper end of branch pipe 130. Branch pipe 130 comprises a vertical section 131 and a transverse section 132. Vertical section 131 extends vertically, while transverse section 132 extends horizontally. The upper end of vertical section 131 is connected to the lower end of restraining pipe 120, while the lower end of vertical section 131 is connected to one end of transverse section 132. The junction between vertical section 131 and transverse section 132 forms a curved pipe. Because turbulent infiltration is suppressed by restraining pipe 120, the fluid velocity at the lower end of vertical section 131 drops to zero. Heat from main line 110 is terminated at the lower end of branch pipe 130 and cannot be transferred to transverse section 132. Consequently, natural convection and thermal stratification in transverse section 132 are prevented.

[0058] In some embodiments, the end of the constraint portion 122 facing the main line 110 is flush with the end face of the cylinder 121 facing the main line 110, so that the constraint cavity 123 extends to the end of the cylinder 121 facing the main line 110. When the fluid in the main line 110 is affected by turbulent penetration and temperature heat transfer and partially flows into the cylinder 121, the vortex is immediately constrained by the constraint portion 122, so that the vortex is quickly destroyed and contained. Furthermore, the two ends of the constraint portion 122 can be further arranged to be flush with the two end faces of the cylinder 121, and the constraint cavity 123 extends to the two ends of the cylinder 121. Thus, any end of the constraint pipe 120 can be selected to be connected to the main line 110, and the other end to be connected to the branch pipe 130, making the assembly between the constraint pipe 120 and the main line 110 and between the constraint pipe 120 and the branch pipe 130 more convenient.

[0059] In other embodiments, the end of the constraint portion 122 facing the main line 110 can also be retracted compared to the end face of the cylinder 121, that is, the end of the constraint portion 122 is located inside the cylinder 121, and a connecting cavity is provided in the cylinder 121. The constraint cavity 123 is connected to the connecting cavity at one end facing the main line 110, and the end of the constraint pipe 120 can be directly connected to the main line 110. The setting of the connecting cavity can play an avoidance role during the assembly process of the two, making the connection between the constraint pipe 120 and the main line 110 more convenient.

[0060] In one embodiment, referring to Figure 1 The pipeline assembly 100 also includes a connecting pipe fitting 140, through which the restraining pipe fitting 120 is connected to the main pipeline 110. The two ends of the connecting pipe fitting 140 are respectively connected to the main pipeline 110 and the restraining pipe fitting 120. One end of the connecting pipe fitting 140 is connected to the radial surface of the main pipeline 110, and the other end of the connecting pipe fitting 140 has the same nominal diameter as the restraining pipe fitting 120, which facilitates the docking and assembly of the connecting pipe fitting 140 and the restraining pipe fitting 120, making the assembly of the pipeline assembly 100 more convenient.

[0061] The connection method between the connecting pipe 140 and the main line 110 is not limited to welding, integral molding, etc. For example, the nominal diameter of the connecting pipe 140 is smaller than the nominal diameter of the main line 110, and the end of the connecting pipe 140 is butted against the radial surface of the main line 110 and welded, so that the inner cavity of the main line 110 is connected to the inner cavity of the connecting pipe 140; or the connecting pipe 140 is integrally connected to the main line 110, and the connecting pipe 140 and the main line 110 are assembled as a whole with the restraining pipe 120. On the one hand, the connection strength between the connecting pipe 140 and the main line 110 is high, and on the other hand, the assembly steps of the connecting pipe 140, the main line 110, and the restraining pipe 120 are simplified. By connecting the restraining pipe 120 with the connecting pipe 140, the fluid in the main line 110 can flow to the restraining pipe 120 and the branch pipe 130, thereby improving the assembly efficiency and convenience of the pipeline assembly 100.

[0062] The end of the connecting pipe 140 facing away from the main line 110 is welded to the restraining pipe 120 to ensure the connection strength between the connecting pipe 140 and the restraining pipe 120. The ends of the connecting pipe 140 and the restraining pipe 120 that butt against each other have the same nominal diameter. This not only facilitates welding between the two, but also allows the inner wall of the connecting pipe 140 to be radially aligned with the inner wall of the barrel 121. This eliminates the need for a stepped end surface on the inner side of the connecting pipe 140 and the restraining pipe 120, thereby reducing resistance and pressure drop during fluid flow and preventing fluid disturbance caused by obstruction of the stepped inner wall.

[0063] In one embodiment, the connecting pipe 140 and the cylinder 121 of the restraining pipe 120 are both configured as straight pipes, and the nominal diameters of the two are the same, and the nominal diameters remain unchanged along their own extension direction. The end of the connecting pipe 140 can be directly connected to the end of the cylinder 121, which is convenient for material acquisition and low in production cost. In another embodiment, the inner diameter of the connecting pipe 140 gradually decreases in the direction toward the constraining pipe 120, that is, the inner cavity of the connecting pipe 140 is in a trumpet shape, and the opening of the inner cavity gradually decreases toward the constraining pipe 120. The outer diameter of the end of the connecting pipe 140 facing the constraining pipe 120 is the same as the outer diameter of the constraining pipe 120, so that the two are directly connected; it is understandable that setting the inner diameter of the connecting pipe 140 to a gradual form can, on the one hand, increase the diameter of the connection point between the connecting pipe 140 and the main pipeline 110, reduce the vortex formed due to the reduction in the flow channel opening, and thereby reduce the influence of turbulent penetration on the thermal stratification of the branch pipe 130; on the other hand, after the fluid enters the connecting pipe 140, it is guided by the inner wall of the connecting pipe 140 and gradually flows toward the constraining pipe 120, so that the fluid is constrained in the connecting pipe 140, further reducing the probability of thermal stratification of the branch pipe 130 due to turbulent penetration.

[0064] It should be noted that, for the case where the restraining pipe fitting 120 is connected to the main line 110 through the connecting pipe fitting 140, in one embodiment, the end of the restraining portion 122 facing the main line 110 protrudes toward the outside of the cylinder 121 toward the main line 110 and is inserted into the connecting pipe fitting 140, and the end of the cylinder 121 facing the main line 110 is docked with the end of the connecting pipe fitting 140 facing away from the main line 110; in this way, the connection between the restraining pipe fitting 120 and the connecting pipe fitting 140 can be achieved, so that the restraining pipe fitting 120 does not need to be directly connected to the main line 110, making the assembly of the restraining pipe fitting 120 and the main line 110 simpler and easier, and the restraining portion 122 can be closer to the main line 110, so that the fluid can be quickly restrained by the restraining portion 122 after flowing out of the main line 110, thereby destroying the vortex and thereby curbing turbulent penetration, so as to more effectively eliminate pipeline thermal stress and thermal fatigue.

[0065] In one embodiment, referring to Figure 5 One side of the multiple constraint parts 122 faces the inner wall of the cylinder 121 and is connected to the inner wall of the cylinder 121, and the corresponding sides of the multiple constraint parts 122 are arranged at intervals along the circumference of the cylinder 121, and the other opposite sides of each constraint part 122 are connected to each other, that is, the constraint parts 122 are respectively connected to the inner wall of the cylinder 121 and other constraint parts 122 on both sides along the radial direction of the cylinder 121, so that a constraint cavity 123 is defined between the opposite sides of adjacent constraint parts 122 and the inner wall of the cylinder 121. Figure 5 As shown in FIG. 1 (a), four constraint portions 122 are provided. The four constraint portions 122 are arranged in a cross shape in the cylinder 121 and define four constraint cavities 123. Figure 5 As shown in Figure (b), there are eight constraint parts 122, which are arranged in a "M" shape in the cylinder 121 and define eight constraint cavities 123; it can be understood that the number of constraint parts 122 is not limited to four or eight, and can also be set to three, six or other numbers.

[0066] It should be noted that, in this embodiment, since the opposing sides of the constraint portion 122 are docked with each other, the docking area of ​​the constraint portion 122 is columnar. When the fluid flows to the end of the docking area of ​​the constraint portion 122, it is restricted by the area and the fluid is diverted and enters different constraint cavities 123 respectively. The docking area of ​​the constraint portion 122 destroys the vortex of the fluid while diverting the fluid, thereby curbing the turbulent penetration of the fluid.

[0067] Reference Figure 6 ,exist Figure 5 After the two configurations of the constraint portion 122 are applied to the constraint pipe 120, the applicant compared the pressure difference between the upper end and the lower end of the branch pipe 130. The upper curve is based on the constraint portion 122 according to the Figure 5 The lower curve is set as shown in Figure (b), with the constraint portion 122 according to Figure 5 Set up as shown in Figure (a) in the figure, from Figure 6 It can be seen that Figure 5 The structure of the "cross"-shaped constraint portion 122 shown in Figure (a) is relatively stable, has little obstruction to the flow of fluid, is easy to process, and can simultaneously meet the requirements of the fluid system for curbing turbulent penetration and reducing fluid pressure drop.

[0068] In another embodiment, referring to Figure 7 , one side of the plurality of constraint portions 122 is arranged at intervals along the circumference of the cylinder 121 and connected to the inner wall of the cylinder 121, and the other side opposite to each constraint portion 122 is connected to the side of the adjacent constraint portion 122, that is, the two opposite sides of each constraint portion 122 are respectively connected to the inner wall of the cylinder 121 and the side of the adjacent constraint portion 122, thereby defining a constraint cavity 123 between the adjacent constraint portion 122 and the inner wall of the cylinder 121, and the sides of all the constraint portions 122 together enclose to form the constraint cavity 123. Figure 7 Four restraining portions 122 are provided. The side portions of adjacent restraining portions 122 and the inner wall of the barrel 121 jointly define a restraining cavity 123. The side portions of four restraining portions 122 jointly define one restraining cavity 123, thereby forming five restraining cavities 123 within the restraining tube 120. The restraining cavity 123 jointly defined by the side portions of the four restraining portions 122 is located in the central area of ​​the barrel 121. It is understood that the number of restraining portions 122 is not limited to four, and may also be five, six, or other numbers.

[0069] In another embodiment, referring to Figure 8 , multiple constraint parts 122 are connected end to end in sequence and enclosed to form a closed ring. The side of all constraint parts 122 facing away from the cylinder 121 jointly defines a constraint cavity 123. The connection points of adjacent constraint parts 122 are all connected to the inner wall of the cylinder 121. Therefore, the constraint cavity 123 is defined between the side of the constraint part 122 facing the inner wall of the cylinder 121 and the inner wall of the cylinder 121. Figure 8 Three restraining portions 122 are provided, and a restraining cavity 123 is defined between the side of each restraining portion 122 and the barrel 121. All restraining portions 122 together define a restraining cavity 123 on the side facing away from the barrel 121, thereby forming four restraining cavities 123 within the restraining tube 120. It is understood that the number of restraining portions 122 is not limited to three, and may also be four, five, six, or other numbers.

[0070] In another embodiment, referring to Figure 9 and Figure 10 The constraint pipe 120 further includes a center column 124, which is located inside the cylinder 121. The constraint portion 122 is located between the center column 124 and the inner wall of the cylinder 121. One side of the plurality of constraint portions 122 is arranged at intervals along the circumference of the cylinder 121 and connected to the inner wall of the cylinder 121. The other side of the plurality of constraint portions 122 is arranged around the circumference of the center column 124 and connected to the circumferential side of the center column 124. Thus, the side portions of adjacent constraint portions 122, the circumferential side of the center column 124 and the inner wall of the cylinder 121 define a constraint cavity 123. Figure 9 As shown in FIG. 1( c ), three constraint portions 122 are provided. The three constraint portions 122 are spaced apart and arranged around the circumference of the central column 124 in the cylinder 121. The three constraint portions 122, the central column 124, and the inner wall of the cylinder 121 define three constraint cavities 123. Figure 9 As shown in Figure (d), there are four constraint parts 122, and the four constraint parts 122 are arranged at intervals around the circumference of the central column 124 in the cylinder 121. The three constraint parts 122 and the central column 124 and the inner wall of the cylinder 121 define four constraint cavities 123; it can be understood that the number of constraint parts 122 is not limited to three or four, and can also be set to five, six or other numbers.

[0071] It can be understood that the center column 124 can be formed by connecting multiple constraint parts 122 at one end facing away from the cylinder 121. In this embodiment, when the fluid flows to the center column 124, it is restricted by the center column 124 and the fluid is diverted and enters different constraint cavities 123 on the side of the center column 124 respectively. While the center column 124 diverts the fluid, it destroys the vortex of the fluid, thereby curbing the turbulent penetration of the fluid.

[0072] The center column 124 is not limited to being configured in the form of a cylinder, a prism, etc. Figure 9 As shown in FIG. 1( c ), the central column 124 is configured as a cylindrical shape. Figure 9 As shown in FIG. 5(d), the central column 124 is configured as a regular quadrangular prism. Figure 10 As shown in FIG. (e), the central column 124 is configured as a flat quadrangular prism. In addition, the central column 124 can be configured as a solid or hollow column. Figure 10 As shown in Figures (e) and (f), the interior of the central column 124 is solid, as shown in Figures (e) and (f). Figure 9 As shown in Figures (c) and (d), the interior of the central column 124 is hollow and forms a central cavity 125 that penetrates the central column 124. The central cavity 125 can play a similar role to the constraint cavity 123. When the fluid flows to the central column 124, it is restricted by the central column 124 and the fluid is diverted and enters different constraint cavities 123 and the central cavity 125 on the side of the central column 124 respectively. While the central column 124 diverts the fluid, it destroys the vortex of the fluid, thereby curbing the turbulent penetration of the fluid.

[0073] The center column 124 can be arranged at the radial center of the cylinder 121, or offset relative to the radial center of the cylinder 121. Figure 10 As shown in FIG. 5( f ), the center column 124 deviates from the center of the cylinder 121 in the radial direction; or Figure 10 In Figure (e), the constraint portions 122 are arranged at intervals around the inner wall of the cylinder 121, and the intervals between adjacent constraint portions 122 are different, or the angles between adjacent constraint portions 122 are different, which makes the constraint cavities 123 defined by the constraint portions 122, the center column 124 and the inner wall of the cylinder 121 different in size; when the constraint pipe 120 is applied to the pipeline assembly 100, the positions of the constraint cavities 123 of different sizes can be adjusted according to the flow direction of the fluid in the main line 110, thereby reducing turbulence. For example, the smaller constraint cavity 123 is set on one side of the cylinder 121 along the flow direction of the fluid in the main line 110, and the larger constraint cavity 123 is set on the other side opposite to the cylinder 121. When the fluid flows through the constraint pipe 120, it will preferentially enter the larger constraint cavity 123. On the one hand, it ensures that the fluid can enter the constraint pipe 120 more smoothly, and on the other hand, it avoids the generation of large vortices due to the fluid impacting the constraint portion 122 in a smaller space.

[0074] In another embodiment, Figure 9As shown in Figures (c) and (d), the radial center of the central column 124 coincides with the radial center of the cylinder 121, or the constraint portions 122 are arranged at equal intervals around the inner wall of the cylinder 121, or the angles between adjacent constraint portions 122 are equal. This makes the constraint cavity 123 formed by the constraint portions 122, the central column 124 and the inner wall of the cylinder 121 uniform in size, so that the fluid entering the constraint pipe 120 can be evenly diverted to different constraint cavities 123, and the flow of the fluid in the constraint pipe 120 is smoother, thereby eliminating turbulent infiltration in the branch pipe 130.

[0075] It should be noted that the constraint pipe fitting 120 is an integrally formed structure. The constraint pipe fitting 120 can be formed by casting, machining, etc., so that the constraint part 122 and the cylinder 121, or the constraint part 122 and the constraint part 122, or the constraint part 122 and the center column 124 are all connected as one piece, so that the constraint pipe fitting 120 has a higher structural strength, simplifies the assembly process of the constraint pipe fitting 120, and can prevent the structure inside the constraint pipe fitting 120 from falling off due to flow resistance and turbulence, thereby adding foreign matter into the pipeline.

[0076] In one embodiment, the length of the constraint pipe 120 is L1, the nominal diameter of the constraint pipe 120 is D, and 2D≤L1≤5D. On the one hand, the constraint pipe 120 has a sufficient length to eliminate eddies and curb turbulent penetration. On the other hand, it avoids the constraint pipe 120 being too long and increasing the difficulty of processing the constraint pipe 120, making the production of the constraint pipe 120 more convenient.

[0077] Furthermore, the thickness of the restraining portion 122 is T1, and the wall thickness of the cylindrical body 121 is T2, with 0.5T2≤T1≤T2. This ensures that the restraining portion 122 has sufficient structural strength to resist turbulence, while also reducing the manufacturing precision of the restraining pipe 120 and improving processing efficiency. The length of the connecting pipe 140 is L2, with 0<L2≤0.5L1. This facilitates the connection of the restraining pipe 120 to the main pipeline 110 through the connecting pipe 140, while also positioning the restraining pipe 120 in the concentrated area of ​​turbulent infiltration within the pipeline to maximize the destruction of vortices and curb turbulent infiltration.

[0078] The present invention also provides a coolant pipe 200 system, referring to Figure 11The coolant pipe 200 system includes the above-mentioned pipe assembly 100 and the coolant pipe 200. The coolant pipe 200 is connected to one end of the main pipe 110. During the operation of the nuclear power plant, the hot fluid flows in the reactor coolant pipe 200 and flows into the main pipe 110. Affected by turbulent penetration and temperature heat transfer, part of the hot fluid enters the constraint pipe 120 through the connecting pipe 140. The turbulence is constrained and rapidly weakened in the constraint pipe 120, and the fluid velocity gradually decreases and drops to almost zero at the lower end of the vertical section 131 of the branch pipe 130, so that the turbulent penetration is effectively curbed. The heat of the hot fluid cannot reach the horizontal section 132 of the branch pipe 130, thereby eliminating the thermal stratification of the branch pipe 130 and reducing the thermal stress and thermal fatigue probability of the coolant pipe 200 system.

[0079] The coolant piping system 200 also includes a connecting line 300, a heat exchanger 400, and a drive pump 500. The two ends of the connecting line 300 are connected to the transverse section 132 and the heat exchanger 400, respectively. The drive pump 500 is used to provide flow power for the fluid in the connecting line 300, allowing the fluid to enter the heat exchanger 400 for temperature adjustment and further processing. In addition, the main line 110, connecting pipe 140, restraining pipe 120, and branch pipe 130 can all be arranged inside the containment, while the connecting line 300, heat exchanger 400, and drive pump 500 are all arranged outside the containment. In addition, a valve 600 is provided between the transverse section 132 and the connecting line 300. The valve 600 can switch the on / off state of the transverse section 132 and the connecting line 300. When the valve 600 is closed, the fluid in the transverse section 132 is in a stagnant state. When the valve 600 is open, the fluid in the transverse section 132 flows into the connecting line 300.

[0080] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A pipe assembly, characterized in that include: Main road; A restraining pipe, comprising a cylinder and a plurality of restraining portions, wherein the restraining portions extend along the length direction of the cylinder and are arranged inside the cylinder, and a plurality of restraining cavities arranged side by side along the radial direction of the cylinder are defined between adjacent restraining portions and / or between the restraining portions and the cylinder; The branch pipe has two ends connected to the main pipe and the branch pipe, and the branch pipe is communicated with the main pipe along the radial direction of the main pipe through the constraint cavity.

2. The pipe assembly according to claim 1, wherein: The length of the restraining pipe is L1, the nominal diameter of the restraining pipe is D, and 2D≤L1≤5D.

3. The pipe assembly according to claim 1, wherein: The thickness of the constraint portion is T1, the wall thickness of the cylinder is T2, and 0.5T2≤T1≤T2.

4. The pipe assembly according to claim 1, wherein: The pipeline assembly further includes a connecting pipe fitting, two ends of which are respectively connected to the main pipe and the restraining pipe fitting.

5. The pipe assembly according to claim 4, wherein: The restraining portion protrudes toward one end of the main pipe to the outside of the cylinder and is inserted into the connecting pipe.

6. The pipe assembly according to claim 4, wherein: The length of the connecting pipe is L2, the length of the restraining pipe is L1, and 0<L2≤0.5L1.

7. The pipe assembly according to claim 4, wherein: The inner diameter of the connecting pipe gradually decreases in a direction toward the restraining pipe, and the outer diameter of one end of the connecting pipe facing the restraining pipe is the same as the outer diameter of the restraining pipe; Alternatively, the nominal diameter of the connecting pipe is the same as the nominal diameter of the restraining pipe.

8. The pipe assembly according to claim 4, wherein: One end of the connecting pipe is integrally connected to the main pipe, and the other end is welded to the restraining pipe; Alternatively, one end of the connecting pipe is welded to the main pipe, and the other end is welded to the restraining pipe.

9. The pipe assembly according to claim 1, wherein: The restraining pipe is an integrally formed structure.

10. The pipe assembly according to any one of claims 1 to 9, characterized in that One side of the plurality of constraint portions is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder, and the other side of each constraint portion is butted against each other, and the adjacent constraint portions and the inner wall of the cylinder define the constraint cavity; Alternatively, one side of a plurality of the constraint portions is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder, and the other side opposite to each constraint portion is connected to the side of an adjacent constraint portion, and the constraint cavity is defined between adjacent constraint portions and the inner wall of the cylinder and between all the constraint portions; Alternatively, a plurality of the restraining portions are connected end to end, and the connection points of adjacent restraining portions are all connected to the inner wall of the cylinder, and the restraining cavity is defined between the restraining portion and the inner wall of the cylinder and between all the restraining portions.

11. The pipe assembly according to any one of claims 1 to 9, characterized in that The constraint tube also includes a center column, which is located inside the cylinder. The constraint part is located between the center column and the inner wall of the cylinder. One side of the multiple constraint parts is arranged at intervals along the circumference of the cylinder and connected to the inner wall of the cylinder. The other side of the multiple constraint parts is connected to the circumferential side of the center column. The adjacent constraint parts, the circumferential side of the center column and the inner wall of the cylinder define the constraint cavity.

12. The pipe assembly according to claim 11, wherein The radial center of the central column coincides with the radial center of the cylinder.

13. The pipe assembly according to claim 11, wherein A central cavity is provided inside the central column.

14. The pipe assembly according to any one of claims 1 to 9, characterized in that The restraining parts are arranged at equal intervals around the inner wall of the cylinder; And / or, the included angles between adjacent constraint portions are equal.

15. Coolant piping system, characterized in that, include: The pipe assembly according to any one of claims 1 to 14; A coolant pipeline is connected to one end of the main pipeline.

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