Reactor coolant loop and installation method thereof

Abstract

The invention discloses a reactor coolant loop and a mounting method thereof. The reactor coolant loop comprises a pressure vessel, a steam generator, a main pump, a hot section main pipeline and a cold section main pipeline. The end face of the steam generator inlet pipe nozzle is parallel to the end face of the steam generator outlet pipe nozzle, the end face of the pressure container inlet pipe nozzle is perpendicular to or parallel to the end face of the pressure container outlet pipe nozzle, and the end face of the pressure container outlet pipe nozzle is parallel to the end face of the steam generator inlet pipe nozzle. And when the main pipeline of the reactor coolant loop is installed and welded, the welding positions of four welding seams at the two ends of the hot-section main pipeline and the two ends of the cold-section main pipeline are in pipeline horizontal fixed butt joint. According to the technical scheme, the reactor coolant loop structure is simplified, the structural restraint degree is further reduced, the welding stress can be further reduced, construction is simplified, the cost is reduced, the construction period is shortened, and the safety and economical efficiency of nuclear power station construction and operation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of nuclear industry coolant pipelines, and in particular to a reactor coolant loop and an installation method thereof. Background Art

[0002] At present, the reactor coolant loop design of domestic pressurized water reactor nuclear power plants is mainly as follows: Figure 1 As shown, this is a "hot section-transition section-cold section" method of the M310 reactor type, which is composed of a reactor pressure vessel, a steam generator, a main pump, a hot section main pipeline, a transition section main pipeline, and a cold section main pipeline. Its disadvantage is that the number of main pipeline installation welds is relatively large. In one loop, there are 2 installation welds in the hot section and cold section respectively, and 4 installation welds in the transition section, with a total of 8 welds. There are 24 welds in the three loops of the million-kilowatt unit, as well as 2G (vertical fixed butt joint of pipelines), 5G (horizontal fixed butt joint of pipelines), and 6G (fixed butt joint of pipelines inclined at 45 degrees), a total of 3 welding positions, resulting in a large workload of main pipeline welding preparation, welding process assessment, welding, non-destructive testing, witnessing parts, etc., and a long installation and welding period.

[0003] Patent CN111599496B proposes a reactor coolant loop that can reduce the number of welds and improve the safety and economy of nuclear power plants. It can reduce the number of three loop installation welds of a million-kilowatt unit from 24 to 12. If the reactor coolant loop of a million-kilowatt unit adopts a two-loop solution with an increased capacity steam generator, the total number of loop installation welds can be further reduced to 8. However, its disadvantages are that it has strict requirements on the manufacturing and installation accuracy of the main equipment, and the construction is difficult; secondly, the reactor coolant loop closed-loop installation weld has a large constraint degree and high welding stress, so a special steam generator temporary support may be required, which makes the construction complicated and the cost increased.

[0004] Patent CN113871036B further proposes a reactor coolant loop that can reduce weld constraint, reduce welding stress, and improve the safety and economy of nuclear power plant construction and operation. However, its disadvantages are that the reactor coolant loop closed-loop installation welds are set at the reactor coolant outlet nozzle and inlet nozzle of the reactor pressure vessel. The shrinkage of the loop closed-loop welds during welding requires the steam generator and the main pipeline to move, which increases the difficulty of construction; second, when the cold section-transition section is set up for adjustment, additional on-site measurement and processing space and transportation and movement are required; third, the loop installation welding needs to be carried out in multiple steps in sequence, and the construction efficiency is low, resulting in extended construction period and increased costs.

[0005] In view of the above technical problems, the present invention is specially introduced. Summary of the invention

[0006] The main purpose of the present invention is to provide a reactor coolant loop and an installation method thereof, which is used to provide a reactor coolant loop and an installation method thereof that can further reduce the constraint degree of the closed-loop installation weld of the reactor coolant loop, reduce the closed-loop installation welding stress and simplify the installation process, and improve the safety and economy of nuclear power plant construction and operation.

[0007] To achieve the above object, according to one aspect of the present invention, a reactor coolant loop is provided, comprising a reactor pressure vessel and a steam generator, the reactor pressure vessel comprising a pressure vessel outlet nozzle and a pressure vessel inlet nozzle, the steam generator comprising a steam generator inlet nozzle and a steam generator outlet nozzle, the reactor coolant loop also comprising a main pipeline, the main pipeline comprising a hot section main pipeline connecting the pressure vessel outlet nozzle and the steam generator inlet nozzle, and a cold section main pipeline connecting the steam generator outlet nozzle and the pressure vessel inlet nozzle;

[0008] The steam generator inlet nozzle end face and the steam generator outlet nozzle end face are parallel to each other, the pressure vessel inlet nozzle end face and the pressure vessel outlet nozzle end face are perpendicular or parallel to each other, and the pressure vessel outlet nozzle end face is parallel to the steam generator inlet nozzle end face; and when the main pipeline of the reactor coolant loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline and both ends of the cold section main pipeline are all horizontal fixed butt joints of the pipelines.

[0009] Further, the reactor coolant loop also includes a main pump, and the hot section main pipeline and / or the cold section main pipeline and the pump casing of the main pump are prefabricated into an integrated structure;

[0010] Alternatively, the main pump is located at the bottom of the steam generator to obtain a steam generator with attached main pump.

[0011] Furthermore, the attached main pump steam generator includes an inlet main pump and an outlet main pump, the inlet main pump includes an inlet main pump pump casing and an inlet main pump motor, the outlet main pump includes an outlet main pump pump casing and an outlet main pump motor, the axial direction of the impeller in the inlet main pump pump casing and the inlet main pump motor is parallel or perpendicular to the horizontal plane, and the axial direction of the impeller in the outlet main pump pump casing and the outlet main pump motor is perpendicular to the horizontal plane.

[0012] Furthermore, an adjustment section is provided at the pipe end of the main pipeline.

[0013] Furthermore, during the installation of the reactor coolant loop, the equipment used includes a steam generator nozzle shadow body, which includes two shadow nozzles corresponding to the steam generator inlet nozzle and the steam generator outlet nozzle, respectively, and the end face dimensions and position dimensions of the two shadow nozzles are consistent with the dimensions of the corresponding nozzles of the steam generator.

[0014] Furthermore, the steam generator nozzle shadow body also includes a shadow body bottom head and a shadow table top. The shadow body bottom head corresponds to the bottom head of the steam generator, and the shadow table top has the same size as the table top supporting the steam generator. The steam generator nozzle shadow body is installed on the steam generator support through the shadow table top of the shadow body bottom head. Two shadow nozzles are arranged on one side of the shadow body bottom head, and a balancing weight is provided on the other side of the shadow body bottom head.

[0015] In order to achieve the above object, according to another aspect of the present invention, a method for installing a reactor coolant loop is provided, which is used to install the above reactor coolant loop. The installation method comprises the following steps:

[0016] The steps of manufacturing and installing the nozzle shadow body are as follows: manufacturing the steam generator nozzle shadow body according to the steam generator, and installing the steam generator nozzle shadow body on the steam generator support;

[0017] The measuring and processing step is to measure and process the adjustment section of the main pipeline end based on the shadow nozzle of the steam generator nozzle shadow body and the nozzle measurement data of the installed reactor pressure vessel;

[0018] A post-processing positioning step is to introduce the measured processed main pipeline into the installation position;

[0019] A nozzle shadow removal step, removing the steam generator nozzle shadow from the steam generator support;

[0020] The steam generator installation step includes introducing the steam generator into the installation position and placing it in position on the steam generator support;

[0021] The installation steps of nozzle and main pipeline group, steam generator nozzle, pressure vessel nozzle and main pipeline group installation;

[0022] Welding step: welding the weld between the nozzle and the main pipe.

[0023] Further, when the end face of the pressure vessel inlet nozzle and the end face of the pressure vessel outlet nozzle are perpendicular to each other, the installation method includes the following steps:

[0024] Before the measurement process step, the reactor pressure vessel and the hot section main pipeline are introduced into the installation position, and the weld between the pressure vessel outlet nozzle end face and the hot section main pipeline pressure vessel side end face is welded;

[0025] In the measuring and processing step, after the steam generator side end face of the hot section main pipeline and the inlet shadow nozzle of the steam generator nozzle shadow body are assembled and installed, the adjustment section of the cold section main pipeline end is measured and processed based on the measured data of the outlet shadow nozzle of the steam generator nozzle shadow body and the inlet nozzle of the pressure vessel and the welding shrinkage amount of the pressure vessel inlet nozzle and the cold section main pipeline weld after correction;

[0026] After the post-processing positioning step, the two ends of the cold section main pipeline are respectively installed with the outlet shadow nozzle of the steam generator nozzle shadow body and the inlet nozzle of the pressure vessel. The end face of the outlet shadow nozzle of the steam generator nozzle shadow body and the end face of the cold section main pipeline are offset by the welding shrinkage amount of the weld between the inlet nozzle of the pressure vessel and the cold section main pipeline.

[0027] Furthermore, the installation method also includes the following steps:

[0028] In the nozzle main pipeline assembly pair installation step, the end face of the steam generator outlet nozzle and the end face of the cold section main pipeline are offset by a welding shrinkage amount of the weld between the pressure vessel inlet nozzle and the cold section main pipeline;

[0029] In the welding process, the weld between the pressure vessel inlet nozzle and the cold section main pipeline is welded first. After the weld shrinks, the end face of the steam generator outlet nozzle is aligned with the end face of the cold section main pipeline, and then the welds between the steam generator inlet nozzle and the hot section main pipeline, and the welds between the steam generator outlet nozzle and the cold section main pipeline are welded simultaneously.

[0030] Furthermore, before the steam generator installation step, the main pipeline room and the steam generator room construction step are also included, and the steam generator room and the main pipeline room can adopt a modular design.

[0031] Further, when the end face of the pressure vessel inlet nozzle and the end face of the pressure vessel outlet nozzle are parallel to each other, the installation method includes the following steps:

[0032] In the measuring and processing step, the adjustment sections of the hot section main pipeline and the cold section main pipeline are measured and processed respectively based on the shadow nozzle of the steam generator nozzle shadow body and the measurement data of the inlet and outlet nozzles of the installed reactor pressure vessel;

[0033] In the nozzle main pipeline assembly and installation step, the cold section main pipeline and the hot section main pipeline are first assembled and installed with the inlet and outlet nozzles of the reactor pressure vessel, and then the cold section main pipeline and the hot section main pipeline are assembled and installed with the inlet and outlet nozzles of the steam generator;

[0034] In the welding step, the pipe ends on both sides of the hot section main pipe and the cold section main pipe are respectively welded to the two nozzles of the reactor pressure vessel and the four welds between the inlet and outlet nozzles of the steam generator at the same time for balance welding.

[0035] By applying the above technical solution of the present invention, at least the following beneficial effects are achieved:

[0036] 1. The present invention adopts a steam generator with inlet and outlet nozzle end faces parallel to each other, a reactor pressure vessel with inlet and outlet nozzle end faces perpendicular to each other, and a special main pump arrangement. When the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline connecting the reactor pressure vessel and the steam generator and at both ends of the cold section main pipeline are all horizontal fixed butt joints of the pipelines, which not only simplifies the reactor coolant loop structure, but also allows the reactor coolant loop closed-loop installation welds to be arranged at the coolant outlet nozzle and the coolant inlet nozzle of the steam generator. When the closed-loop installation welding shrinks, only the steam generator needs to be moved without moving the main pipeline, which further reduces the structural constraint and reduces the welding stress.

[0037] 2. The reactor coolant loop installation method of the present invention is equivalent to installing the actual steam generator to the specified position by designing and installing the steam generator nozzle shadow, so that the relevant dimensional data of the adjustment sections at both ends of the main pipeline can be measured in advance to ensure that the steam generator can be matched with the main pipeline with high precision, and the additional on-site measurement and processing space and transportation movement can be avoided.

[0038] 3. When the reactor coolant loop of the present invention adopts a reactor pressure vessel with inlet and outlet nozzle end faces parallel to each other, the installation welds of the loop can be optimized from multiple steps of sequential welding to one step of simultaneous welding, thereby greatly improving the construction efficiency.

[0039] 4. The embodiment of the present invention simplifies the reactor coolant loop structure and the installation and construction process and complexity, which is conducive to reducing costs, shortening construction period, and improving the safety and economy of nuclear power plant construction and operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0041] Figure 1 A schematic diagram of a reactor coolant loop in the prior art is shown;

[0042] Figure 2 A bottom schematic diagram of a reactor coolant loop of Example 1 is shown;

[0043] Figure 3 A side view of the reactor coolant loop of Example 1 is shown;

[0044] Figure 4 A schematic diagram of a steam generator of Example 1 is shown;

[0045] Figure 5 A schematic diagram of the pressure vessel of Example 1 is shown;

[0046] Figure 6 A schematic diagram showing the prefabrication of the main pump casing and the cold section main pipeline of Example 1 into one piece;

[0047] Figure 7 A front view of the steam generator nozzle shadow after installation is shown;

[0048] Figure 8 A side view of the steam generator nozzle shadow after installation is shown;

[0049] Fig. 9 A bottom schematic diagram of a reactor coolant loop of Example 2 is shown;

[0050] Fig.10 A side view of the reactor coolant loop of Embodiment 2 or Embodiment 4 is shown;

[0051] Fig.11 A schematic diagram of a steam generator with a main pump according to Embodiment 2 is shown;

[0052] Fig.12 A bottom schematic diagram of a reactor coolant loop in Embodiment 4 is shown;

[0053] Fig.13 A schematic diagram of a pressure vessel of Example 4 is shown;

[0054] Fig.14 Another bottom schematic diagram of a reactor coolant loop of Embodiment 4 is shown;

[0055] Fig.15 Another reactor coolant loop side view expansion schematic diagram of Example 4 is shown.

[0056] The above drawings include the following reference numerals:

[0057] 1. Reactor pressure vessel; 2. Pressure vessel inlet nozzle end face; 3. Pressure vessel inlet nozzle; 4. Pressure vessel outlet nozzle end face; 5. Pressure vessel outlet nozzle; 6. Main pump pressure vessel side cold section main pipeline end face; 7. Main pump pressure vessel side main pipeline; 8. Main pump; 9. Main pump steam generator side cold section main pipeline end face; 10. Main pump steam generator side main pipeline; 11. Steam generator outlet nozzle end face; 12. Steam generator outlet nozzle; 13. Steam generator; 14. Steam generator inlet nozzle; 15. Steam generator inlet nozzle end face; 16. Hot section main pipeline steam generator side end face; 17. Hot section main pipeline; 1 8. Side end face of the pressure vessel of the hot section main pipeline; 19. Side end face of the pressure vessel of the cold section main pipeline; 20. Cold section main pipeline; 21. Side end face of the steam generator of the cold section main pipeline; 22. End face of the outlet nozzle of the attached main pump steam generator; 23. Outlet nozzle of the attached main pump steam generator; 24. Pump casing of the outlet main pump; 25. Motor of the outlet main pump; 26. Steam generator of the attached main pump; 27. Motor of the inlet main pump; 28. Pump casing of the inlet main pump; 29. ​​Inlet nozzle of the attached main pump steam generator; 30. End face of the inlet nozzle of the attached main pump steam generator; 31. Shadow nozzle; 32. Bottom cover of the shadow body; 33. Balance weight; 34. Shadow table; 35. Steam generator support. DETAILED DESCRIPTION

[0058] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0059] The present invention is further described in detail below in conjunction with specific embodiments, and these embodiments cannot be understood as limiting the scope of protection claimed by the present invention. The term "including" when used indicates the existence of a feature, but does not exclude the existence or addition of one or more other features; the orientation or position relationship indicated by the terms "lateral", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention; in addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0060] In the description, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0061] Embodiment 1:

[0062] like Figure 2 and Figure 3 As shown, a specific embodiment 1 of the present invention provides a reactor coolant loop, including a reactor pressure vessel 1 and a steam generator 13. Figure 4 As shown, the bottom end of the steam generator 13 is provided with a steam generator inlet nozzle 14 and a steam generator outlet nozzle 12. The steam generator inlet nozzle end face 15 is parallel to the steam generator outlet nozzle end face 11. Figure 5 As shown, the reactor pressure vessel 1 is provided with a pressure vessel inlet nozzle 3 and a pressure vessel outlet nozzle 5, and the pressure vessel inlet nozzle end face 2 and the pressure vessel outlet nozzle end face 4 are perpendicular to each other.

[0063] The reactor coolant loop also includes a hot section main pipeline 17 connecting the pressure vessel outlet nozzle 5 and the steam generator inlet nozzle 14, and a cold section main pipeline connecting the steam generator outlet nozzle 12 and the pressure vessel inlet nozzle 3.

[0064] like Figure 6 As shown, the reactor coolant loop also includes a main pump 8. The main pipeline 7 on the pressure vessel side of the main pump, the main pipeline 10 on the steam generator side of the main pump and the pump casing of the main pump 8 are prefabricated into an integrated structure, namely, the cold section main pipeline. The end face 6 of the cold section main pipeline on the pressure vessel side of the main pump and the end face 9 of the cold section main pipeline on the steam generator side of the main pump are perpendicular to each other.

[0065] Figure 2In the figure, the end face 16 on the steam generator side of the hot section main pipe and the end face 18 on the pressure vessel side of the hot section main pipe are the two end faces of the hot section main pipe 17. The hot section main pipe 17 is connected between the steam generator inlet nozzle end face 15 and the steam generator side end face 16 of the hot section main pipe and the pressure vessel outlet nozzle end face 4 and the pressure vessel side end face 18 of the hot section main pipe, and is connected between the steam generator inlet nozzle 14 and the pressure vessel outlet nozzle 5. The cold section main pipe of the integrated structure is connected between the pressure vessel inlet nozzle 3 and the steam generator outlet nozzle 12 by welding the pressure vessel inlet nozzle end face 2 and the main pump pressure vessel side cold section main pipe end face 6 and the main pump steam generator side cold section main pipe end face 9 and the steam generator outlet nozzle end face 11, and the pressure vessel outlet nozzle end face 4 is parallel to the steam generator inlet nozzle end face 15.

[0066] The reactor coolant loop as described above, such as Figure 3 As shown, when the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline 17 and both ends of the cold section main pipeline are all fixedly butted horizontally.

[0067] Further, the reactor coolant loop as described above, such as Figure 2 As shown, the pipe end of the main pipeline 10 on the main pump steam generator side and the pipe end of the main pipeline 7 on the main pump pressure vessel side are both provided with adjustment sections.

[0068] like Figure 7 and Figure 8 As shown, during the installation of the reactor coolant loop, a steam generator nozzle shadow body is made, and the steam generator nozzle shadow body includes an inlet shadow nozzle and an outlet shadow nozzle corresponding to the steam generator inlet nozzle 14 and the steam generator outlet nozzle 12 respectively. The end face size and position size of the two shadow nozzles 31 are consistent with the size of the corresponding nozzle of the steam generator 13.

[0069] Furthermore, the steam generator nozzle shadow body also includes a shadow body bottom head 32 and a shadow table 34. The shadow body bottom head 32 corresponds to the bottom head of the steam generator 13. The shadow table 34 has the same size as the table supporting the steam generator 13. The shadow body bottom head 32 is installed on the steam generator support 35 through the shadow table 34. Two shadow nozzles 31 are arranged on one side of the shadow body bottom head 32. A balancing weight 33 is arranged on the other side of the shadow body bottom head 32. In specific implementation, the steam generator nozzle shadow body can be manufactured and used in a mechanical or electromechanical entity manner, or in an electronic virtual body manner using three-dimensional scanning technology.

[0070] Preferably, the reactor coolant loop as described above, the steam generator 13 room and the main pump 8, the main pipeline 7 on the main pump pressure vessel side, the main pipeline 10 room on the main pump steam generator side and the hot section main pipeline 17 room adopt a modular design.

[0071] like Figure 2 and Figure 3 As shown, a method for installing a reactor coolant loop as described above comprises the following steps:

[0072] (1) The reactor pressure vessel 1 and the hot section main pipeline 17 are respectively introduced into the installation position.

[0073] (2) Install the weld between the pressure vessel outlet nozzle end face 4 and the hot section main pipeline pressure vessel side end face 18.

[0074] (3) Nozzle shadow production and installation steps, such as Figure 7 and Figure 8 As shown, after the shadow table 34 of the steam generator nozzle shadow and the end face dimensions and position dimensions of the two shadow nozzles 31 are adjusted and copied to be identical to the corresponding dimensions of the actual steam generator 13 support table and nozzle end faces 11, 15, the steam generator nozzle shadow is installed on the steam generator support 35. This step is equivalent to installing the actual steam generator 13 on the steam generator support 35.

[0075] (4) The end face 16 of the steam generator side of the hot section main pipeline is assembled with the end face of the inlet nozzle of the steam generator nozzle shadow body; the data between the end face of the outlet nozzle of the steam generator nozzle shadow body and the end face 2 of the inlet nozzle of the pressure vessel are measured, and after correction according to the welding shrinkage amount of the weld between the inlet nozzle 3 of the pressure vessel and the cold section main pipeline, the measured processing dimensions of the main pipeline 10 on the steam generator side of the main pump with the pump casing of the main pump 8 and the main pipeline 7 on the pressure vessel side of the main pump are obtained, which are suitable for the installation in step (7).

[0076] (5) Based on the measured and processed dimensional data of the main pipeline 10 on the steam generator side of the main pump with the pump casing of the main pump 8 and the main pipeline 7 on the pressure vessel side of the main pump, which are suitable for installation, the adjustment sections of the pipe ends of the cold section main pipeline of the integrated structure are measured and processed to obtain the cold section main pipeline suitable for installation in step (7).

[0077] (6) After processing, the cold section main pipeline suitable for step (7) is introduced into the installation position and put into place after measurement and processing.

[0078] (7) Assemble and install the steam generator nozzle shadow body outlet nozzle end face, the main pump steam generator side main pipeline 10 with the main pump 8 pump shell and the main pump pressure vessel side main pipeline 7, and the pressure vessel inlet nozzle end face 2; wherein, the steam generator nozzle shadow body outlet nozzle end face and the main pump steam generator side cold section main pipeline end face 9 are offset by a section to obtain the welding shrinkage of the weld between the pressure vessel inlet nozzle end face 2 and the main pump pressure vessel side cold section main pipeline end face 6.

[0079] (8) Construction of modules in the steam generator room and main pipeline room.

[0080] (9) Nozzle shadow removal step, removing the steam generator nozzle shadow.

[0081] (10) Steam generator installation step: the steam generator 13 is introduced into the installation position and positioned on the steam generator support 35.

[0082] (11) The nozzle main pipeline assembly installation step, the steam generator inlet nozzle end face 15 is assembled with the hot section main pipeline steam generator side end face 16, and the steam generator outlet nozzle end face 11 is assembled with the main pump steam generator side cold section main pipeline end face 9, wherein the steam generator outlet nozzle end face 11 and the main pump steam generator side cold section main pipeline end face 9 are offset by a welding shrinkage amount of the weld between the pressure vessel inlet nozzle end face 2 and the main pump pressure vessel side cold section main pipeline end face 6.

[0083] (12) Weld the weld between the pressure vessel inlet nozzle end face 2 and the main pipeline end face 6 of the cold section on the pressure vessel side of the main pump.

[0084] (13) After the weld seam between the pressure vessel inlet nozzle end face 2 and the main pipe end face 6 of the cold section on the pressure vessel side of the main pump is shrunk, the steam generator outlet nozzle end face 11 is aligned with the main pipe end face 9 of the cold section on the steam generator side of the main pump.

[0085] (14) At the same time, the weld between the cold section main pipe end face 9 on the main pump steam generator side and the steam generator outlet nozzle end face 11 and the weld between the hot section main pipe steam generator side end face 16 and the steam generator inlet nozzle end face 15 are welded to complete a reactor coolant loop installation welding.

[0086] During the welding contraction, only the steam generator 13 moves, which reduces the structural constraint, welding stress and construction complexity compared with the prior art which requires the steam generator and the cold section main pipeline and the hot section main pipeline to move together.

[0087] Embodiment 2:

[0088] like Fig. 9 and Fig.10 As shown, the present invention also provides another specific embodiment of the reactor coolant loop, connecting the reactor pressure vessel 1 and the attached main pump steam generator 26 through a hot section main pipeline 17 and a cold section main pipeline 20, the hot section main pipeline 17 is connected between the pressure vessel outlet nozzle 5 and the attached main pump steam generator inlet nozzle 29, and the cold section main pipeline 20 is connected between the attached main pump steam generator outlet nozzle 23 and the pressure vessel inlet nozzle 3.

[0089] The cold section main pipeline pressure vessel side end face 19 and the cold section main pipeline steam generator side end face 21 are perpendicular to each other, wherein, Figure 5 As shown, the reactor pressure vessel 1 is provided with a pressure vessel inlet nozzle 3 and a pressure vessel outlet nozzle 5, and the pressure vessel inlet nozzle end face 2 and the pressure vessel outlet nozzle end face 4 are perpendicular to each other. Fig.11 As shown, the attached main pump steam generator inlet nozzle end face 30 of the attached main pump steam generator 26 of the inlet main pump pump housing 28 and the attached main pump steam generator outlet nozzle end face 22 of the attached main pump steam generator 26 of the outlet main pump pump housing 24 are parallel to each other.

[0090] The reactor coolant loop as described above, such as Fig.10 As shown, the axial direction of the main pump impeller in the inlet main pump casing 28 and the inlet main pump motor 27 attached to the main pump steam generator 26 is parallel to the horizontal plane, and the axial direction of the main pump impeller in the outlet main pump casing 24 and the outlet main pump motor 25 attached to the main pump steam generator 26 is perpendicular to the horizontal plane. This main pump impeller axial setting adopts the same shaft inlet and outlet method as the existing main pump, which can make full use of the existing main pump and hydraulic design to achieve an equivalent pumping effect, and the bottom head water chamber structure of the main pump steam generator can be simplified from one inlet and two outlets to one inlet and one outlet, reducing the head opening.

[0091] Alternatively, after modifying the hydraulic design to adopt a radial-in and axial-out method, the main pump propeller blades in the inlet main pump casing 28 and the axial direction of the inlet main pump motor 27 can also be arranged perpendicular to the horizontal plane.

[0092] A reactor coolant loop as described above, wherein Fig.10 As shown, when the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline 17 and the two ends of the cold section main pipeline 20 are all horizontal fixed butt joints of the pipelines.

[0093] Preferably, wherein Fig. 9 As shown, the pipe ends of the cold section main pipeline 20 are respectively provided with adjustment sections near the cold section main pipeline pressure vessel side end face 19 and the cold section main pipeline steam generator side end face 21.

[0094] Further, such as Figure 7 and 8 As shown, a steam generator nozzle shadow body is made, and the steam generator nozzle shadow body includes two shadow nozzles 31 corresponding to the outlet nozzle 23 of the attached main pump steam generator and the inlet nozzle 29 of the attached main pump steam generator respectively. The end face size and position size of the two shadow nozzles 31 are consistent with the corresponding sizes of the end faces 22 and 30 of the corresponding nozzles of the attached main pump steam generator 26.

[0095] Furthermore, the shadow body of the steam generator nozzle also includes a shadow body bottom head 32 and a shadow table 34. The shadow body bottom head 32 corresponds to the bottom head of the attached main pump steam generator 26. The shadow table 34 has the same size as the table supporting the attached main pump steam generator 26. The shadow body bottom head 32 is installed on the steam generator support 35 through the shadow table 34. Two shadow nozzles 31 are arranged on one side of the shadow body bottom head 32. A balancing weight 33 is arranged on the other side of the shadow body bottom head 32. In specific implementation, the steam generator nozzle shadow body can be made and used in a mechanical or electromechanical entity manner, or it can be made and used in an electronic virtual body manner using three-dimensional scanning technology.

[0096] Preferably, the reactor coolant loop as described above, the room with the main pump steam generator 26 and the rooms of the hot section main pipeline 17 and the cold section main pipeline 20 adopt a modular design.

[0097] like Fig. 9 and Fig.10 As shown, the installation method of the reactor coolant loop in this embodiment includes the following steps:

[0098] (1) The reactor pressure vessel 1 and the hot section main pipeline 17 are respectively introduced into the installation position.

[0099] (2) Install the weld between the pressure vessel outlet nozzle end face 4 and the hot section main pipeline pressure vessel side end face 18.

[0100] (3) Figure 7 and Figure 8 As shown, after the end face dimensions and position dimensions of the shadow table 34 and shadow nozzle 31 of the steam generator nozzle shadow are adjusted and copied to be identical to the corresponding dimensions of the support table and nozzle end faces 22 and 30 of the actual attached main pump steam generator 26, the steam generator nozzle shadow is installed on the steam generator support 35. This step is equivalent to installing the actual attached main pump steam generator 26 on the steam generator support 35.

[0101] (4) The steam generator side end face 16 of the hot section main pipeline is assembled with the inlet shadow nozzle 31 end face of the steam generator nozzle shadow body; the data between the outlet shadow nozzle end face of the steam generator nozzle shadow body and the inlet nozzle end face 2 of the pressure vessel are measured, and after correction according to the welding shrinkage amount of the pressure vessel inlet nozzle 3 and the cold section main pipeline weld, the measured processing dimensions of the cold section main pipeline 20 suitable for installation in step (7) are obtained.

[0102] (5) Based on the measured and processed dimension data of the cold section main pipeline 20 suitable for installation obtained in step (4), the pipe end adjustment section of the cold section main pipeline 20 is measured and processed to obtain the cold section main pipeline 20 suitable for installation in step (7).

[0103] (6) The cold section main pipeline 20 suitable for installation in step (7) is introduced into the installation position after processing.

[0104] (7) Assemble and install the outlet nozzle end face of the steam generator nozzle shadow body, the cold section main pipeline 20, and the pressure vessel inlet nozzle end face 2; wherein, the outlet nozzle end face of the steam generator nozzle shadow body and the steam generator side end face 21 of the cold section main pipeline are offset by a section of the welding shrinkage amount of the weld between the pressure vessel inlet nozzle end face 2 and the pressure vessel side end face 19 of the cold section main pipeline.

[0105] (8) Construction of modules in the steam generator room and main pipeline room.

[0106] (9) Remove the steam generator nozzle shadow.

[0107] (10) The main pump steam generator 26 is introduced into the installation position and placed in place on the steam generator support.

[0108] (11) The inlet nozzle end face 30 of the attached main pump steam generator is paired with the side end face 16 of the hot section main pipeline steam generator, and the outlet nozzle end face 22 of the attached main pump steam generator is paired with the side end face 21 of the cold section main pipeline steam generator; wherein, the outlet nozzle end face 22 of the attached main pump steam generator and the side end face 21 of the cold section main pipeline steam generator are offset by the welding shrinkage of the weld between the inlet nozzle end face 2 of the pressure vessel and the side end face 19 of the cold section main pipeline pressure vessel.

[0109] (12) Weld the weld between the pressure vessel inlet nozzle end face 2 and the cold section main pipeline pressure vessel side end face 19.

[0110] (13) After the weld seam between the pressure vessel inlet nozzle end face 2 and the cold section main pipeline pressure vessel side end face 19 is shrunk, the main pump steam generator outlet nozzle end face 22 is aligned with the cold section main pipeline steam generator side end face 21.

[0111] (14) At the same time, the weld seam between the outlet nozzle end face 22 of the steam generator of the attached main pump and the side end face 21 of the steam generator of the cold section main pipeline and the weld seam between the side end face 16 of the steam generator of the hot section main pipeline and the inlet nozzle end face 30 of the steam generator of the attached main pump are welded to complete the installation welding of a reactor coolant loop. During welding, this welding contraction only drives the steam generator of the attached main pump 26 to move. Compared with the reference technology welding contraction that needs to drive the steam generator and the main pipeline to move, the structural constraint is relatively reduced, the welding stress can be reduced, and the construction complexity is simplified.

[0112] Embodiment 3:

[0113] Under the condition that both the hot section main pipeline 17 and the cold section main pipeline 20 can be introduced from the steam generator room into the main pipeline room, another method for installing a reactor coolant loop as described in Example 2 includes the following steps:

[0114] (1) After the construction of the reactor pressure vessel room, steam generator room and main pipeline room is completed, Fig. 9 and Fig.10 As shown, the reactor pressure vessel 1 and the hot section main pipeline 17 are respectively introduced into the installation positions.

[0115] (2) Install the weld between the pressure vessel outlet nozzle end face 4 and the hot section main pipeline pressure vessel side end face 18.

[0116] (3) Figure 7 and Figure 8 As shown, after the end face dimensions and position dimensions of the shadow table 34 and shadow nozzle 31 of the steam generator nozzle shadow are adjusted and copied to be identical to the corresponding dimensions of the support table and nozzle end faces 22 and 30 of the actual attached main pump steam generator 26, the steam generator nozzle shadow is installed on the steam generator support 35. This step is equivalent to installing the actual attached main pump steam generator 26 on the steam generator support 35.

[0117] (4) The steam generator side end face 16 of the hot section main pipeline is assembled with the inlet shadow nozzle 31 end face of the steam generator nozzle shadow body; the data between the outlet shadow nozzle end face of the steam generator nozzle shadow body and the inlet nozzle end face 2 of the pressure vessel are measured, and after correction, the measured processing dimensions of the cold section main pipeline 20 suitable for installation in step (9) are obtained.

[0118] (5) Based on the measured and processed dimension data of the cold section main pipeline 20 suitable for installation obtained in step (4), the pipe end adjustment section of the cold section main pipeline 20 is measured and processed to obtain the cold section main pipeline 20 suitable for installation in step (9).

[0119] (6) Remove the steam generator nozzle shadow.

[0120] (7) The cold section main pipeline 20 installed in step (9) is introduced into the installation position.

[0121] (8) The steam generator 26 of the attached main pump is introduced into the installation position and placed in place on the steam generator support.

[0122] (9) The inlet nozzle end face 30 of the attached main pump steam generator is paired with the side end face 16 of the hot section main pipeline steam generator, and the outlet nozzle end face 22 of the attached main pump steam generator is paired with the side end face 21 of the cold section main pipeline steam generator; wherein, the outlet nozzle end face 22 of the attached main pump steam generator and the side end face 21 of the cold section main pipeline steam generator are offset by the welding shrinkage of the weld between the inlet nozzle end face 2 of the pressure vessel and the side end face 19 of the cold section main pipeline pressure vessel.

[0123] (10) Weld the weld between the pressure vessel inlet nozzle end face 2 and the cold section main pipeline pressure vessel side end face 19.

[0124] (11) After the weld seam between the pressure vessel inlet nozzle end face 2 and the cold section main pipeline pressure vessel side end face 19 is shrunk, the main pump steam generator outlet nozzle end face 22 is aligned with the cold section main pipeline steam generator side end face 21.

[0125] (12) At the same time, the weld seams between the outlet nozzle end face 22 of the steam generator of the attached main pump and the side end face 21 of the steam generator of the cold section main pipeline and the weld seams between the side end face 16 of the steam generator of the hot section main pipeline and the inlet nozzle end face 30 of the steam generator of the attached main pump are welded to complete the installation welding of a reactor coolant loop. The beneficial effect of embodiment 3 is that there is no installation of embodiment 1 and embodiment 2, and the civil engineering is cross-constructed, which is more conducive to ensuring the installation quality.

[0126] Embodiment 4:

[0127] Based on Example 1, Example 2, and Example 3, Fig.12 , 13 and Fig.14 As shown, a specific embodiment of the present invention provides a reactor coolant loop in which the reactor pressure vessel outlet nozzle end face 4 and the reactor pressure vessel inlet nozzle end face 2 are parallel to each other, and the steam generator inlet nozzle end face and the outlet nozzle end face are also parallel to each other.

[0128] Among them, Fig.14 and 15 As shown, a main pump 8 is provided on each of the hot section main pipeline and the cold section main pipeline, and the main pipeline 7 on the main pump pressure vessel side, the main pipeline 10 on the main pump steam generator side and the pump casing of the main pump 8 are prefabricated as an integrated structure. This arrangement can utilize the existing main pump design to increase the pumping capacity and increase the capacity of the nuclear power unit.

[0129] Preferably, the main pump 8 is arranged away from the center line of the reactor pressure vessel and the steam generator, which can reduce the distance between the reactor pressure vessel 1 and the steam generator 13 and make the reactor coolant loop more compact. Adjustment sections are respectively provided at the ends of the hot section main pipeline and the cold section main pipeline. When the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline and the cold section main pipeline are all fixedly butted horizontally.

[0130] The pressure vessel outlet nozzle 5 is welded to the main pipeline 7 on the pressure vessel side of the hot section main pipeline through the pressure vessel outlet nozzle end face 4 and the end face 18 on the pressure vessel side of the hot section main pipeline, and the pressure vessel inlet nozzle 3 is welded to the main pipeline 7 on the pressure vessel side of the main pump pressure vessel through the pressure vessel inlet nozzle end face 2 and the main pipeline end face 6 on the cold section main pipeline on the pressure vessel side of the main pump pressure vessel. The steam generator inlet nozzle 14 is welded to the main pipeline 10 on the steam generator side of the hot section main pipeline through the steam generator inlet nozzle end face 15 and the end face 16 on the steam generator side of the hot section main pipeline, and the steam generator outlet nozzle 12 is welded to the main pipeline 10 on the steam generator side of the cold section main pipeline on the steam generator side of the main pump steam generator. The pressure vessel outlet nozzle end face 4 and the pressure vessel inlet nozzle end face 2 are parallel to each other, and are also parallel to the steam generator inlet nozzle end face 15 and the steam generator outlet nozzle end face 11.

[0131] like Fig.10 and 12 As shown, the hot section main pipeline 17 and the cold section main pipeline 20 are connected at Fig.13 The reactor pressure vessel 1 and Fig.11 As shown, between the attached main pump steam generator 26, the pressure vessel outlet nozzle 5 is welded via the pressure vessel outlet nozzle end face 4 and the pressure vessel side end face 18 of the hot section main pipeline to be connected to the hot section main pipeline 17, the pressure vessel inlet nozzle 3 is welded via the pressure vessel inlet nozzle end face 2 and the pressure vessel side end face 19 of the cold section main pipeline to be connected to the cold section main pipeline 20, the attached main pump steam generator inlet nozzle 29 is welded via the attached main pump steam generator inlet nozzle end face 30 and the steam generator side end face 16 of the hot section main pipeline to be connected to the hot section main pipeline 17, and the attached main pump steam generator outlet nozzle 23 is welded via the attached main pump steam generator outlet nozzle end face 22 and the steam generator side end face 21 of the cold section main pipeline to be connected to the cold section main pipeline 20.

[0132] The pressure vessel outlet nozzle end face 4 and the pressure vessel inlet nozzle end face 2 are parallel to each other, and are also parallel to the attached main pump steam generator inlet nozzle end face 30 and the attached main pump steam generator outlet nozzle end face 22. When the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline 17 and the two ends of the cold section main pipeline 20 are all fixedly butted horizontally.

[0133] The two reactor coolant loop installation methods described above specifically include the following steps:

[0134] like Fig.10 and Fig.12 As shown, or as Fig.14 and Fig.15 As shown,

[0135] (1) The reactor pressure vessel 1 is introduced into the installation position.

[0136] (2) The steps of making and installing the nozzle shadow body are as follows: the table top, nozzle end face dimensions and position dimensions of the nozzle shadow body of the steam generator 13 or the steam generator with main pump 26 are made, adjusted and copied to be the same as the corresponding dimensions of the table top and nozzle of the actual steam generator, and then the nozzle shadow body of the steam generator 13 or 26 is installed on the steam generator support 35.

[0137] (3) Fig.12 The measurement shown is of the nozzle shadow inlet and outlet nozzle end faces of the steam generator 26 of the main pump, the pressure vessel inlet nozzle end face 2, and the pressure vessel outlet nozzle end face 4.

[0138] or Fig.14 The nozzle shadow inlet and outlet shadow nozzle end faces of the steam generator 13 and the pressure vessel inlet nozzle end face 2 and the pressure vessel outlet nozzle end face 4 are measured.

[0139] (4) Based on the measurement data between the inlet and outlet nozzle end faces of the nozzle shadow body of the attached main pump steam generator 26 and the pressure vessel inlet nozzle end face 2 and the pressure vessel outlet nozzle end face 4, the pipe end adjustment sections of the hot section main pipeline 17 and the cold section main pipeline 20 are measured and processed.

[0140] or Fig.14 As shown, the pipe end adjustment sections of the main pipeline 7 on the main pump pressure vessel side and the main pipeline 10 on the main pump steam generator side are measured and processed based on the measurement data between the nozzle end faces of the steam generator 13 and the pressure vessel inlet nozzle end face 2 and the pressure vessel outlet nozzle end face 4.

[0141] (5) Nozzle shadow removal steps, removing the steam generator nozzle shadow.

[0142] (6) After processing, the hot section main pipeline and the cold section main pipeline are measured and processed and then introduced into the installation position.

[0143] (7) Fig.12 As shown, the hot section main pipeline pressure vessel side end face 18 and the pressure vessel outlet nozzle end face 4, the cold section main pipeline pressure vessel side end face 19 and the pressure vessel inlet nozzle end face 2 are installed in pairs.

[0144] or Fig.14 As shown, the main pipeline end face 6 of the cold section on the pressure vessel side of the main pump and the pressure vessel inlet nozzle end face 2, and the main pipeline end face 18 of the hot section on the pressure vessel side and the pressure vessel outlet nozzle end face 4 are installed in pairs.

[0145] (8) Construction of steam generator room and main pipeline room.

[0146] (9) The steam generator 13 or the steam generator with main pump 26 is introduced into the installation position.

[0147] (10) Fig.12 As shown, the hot section main pipeline steam generator side end face 16, the cold section main pipeline steam generator side end face 21 and the attached main pump steam generator inlet nozzle end face 30, and the attached main pump steam generator outlet nozzle end face 22 are installed in pairs.

[0148] or Fig.14 As shown, the hot section main pipeline steam generator side end face 16, the main pump steam generator side cold section main pipeline end face 9 and the steam generator inlet nozzle end face 15, the steam generator outlet nozzle end face 11 are installed in pairs.

[0149] (11) Fig.12 As shown, the weld between the inlet nozzle end face 30 of the attached main pump steam generator and the side end face 16 of the hot section main pipeline steam generator, the weld between the outlet nozzle end face 22 of the attached main pump steam generator and the side end face 21 of the cold section main pipeline steam generator, the weld between the inlet nozzle end face 2 of the pressure vessel and the side end face 19 of the cold section main pipeline pressure vessel, and the weld between the outlet nozzle end face 4 of the pressure vessel and the side end face 18 of the hot section main pipeline pressure vessel are welded simultaneously and evenly, thereby completing a reactor coolant loop installation welding.

[0150] or Fig.14 As shown, the welds of the steam generator inlet nozzle end face 15 and the hot section main pipe steam generator side end face 16, the welds of the steam generator outlet nozzle end face 11 and the main pump steam generator side cold section main pipe end face 9, the welds of the pressure vessel inlet nozzle end face 2 and the main pump pressure vessel side cold section main pipe end face 6, and the welds of the pressure vessel outlet nozzle end face 4 and the hot section main pipe pressure vessel side end face 18 are balanced and welded at the same time, thus completing a reactor coolant loop installation welding.

[0151] The balanced welding described above is to minimize the difference in welding shrinkage of each weld by symmetrical welding, monitoring welding heat input and welding deformation, so as to avoid excessive welding stress.

[0152] Compared with the reference technology which requires multiple steps to complete the installation welding of a reactor coolant loop, this solution can complete the installation welding of a reactor coolant loop in one step, greatly improving the construction efficiency.

[0153] In summary, from the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0154] 1. The present invention adopts a steam generator with inlet and outlet nozzle end faces parallel to each other, a reactor pressure vessel with inlet and outlet nozzle end faces perpendicular to each other, and a special main pump arrangement. When the main pipeline of the entire loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline connecting the reactor pressure vessel and the steam generator and at both ends of the cold section main pipeline are all horizontal fixed butt joints of the pipelines, which not only simplifies the reactor coolant loop structure, but also allows the reactor coolant loop closed-loop installation welds to be arranged at the coolant outlet nozzle and the coolant inlet nozzle of the steam generator. When the closed-loop installation welding shrinks, only the steam generator needs to be moved without moving the main pipeline, which further reduces the structural constraint and reduces the welding stress.

[0155] 2. The reactor coolant loop installation method of the present invention is equivalent to installing the actual steam generator to the specified position by designing and installing the steam generator nozzle shadow, so that the relevant dimensional data of the adjustment sections at both ends of the main pipeline can be measured in advance to ensure that the steam generator can be matched with the main pipeline with high precision, avoiding the additional on-site measurement and processing space and transportation movement.

[0156] 3. When the reactor coolant loop of the present invention adopts a reactor pressure vessel with inlet and outlet nozzle end faces parallel to each other, the installation welds of the loop can be optimized from multiple steps of sequential welding to one step of simultaneous welding, thereby greatly improving the construction efficiency.

[0157] 4. The embodiment of the present invention simplifies the reactor coolant loop structure and the installation and construction process and complexity, which is conducive to reducing costs, shortening construction period, and improving the safety and economy of nuclear power plant construction and operation.

[0158] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A reactor coolant loop, comprising a reactor pressure vessel and a steam generator, wherein the reactor pressure vessel comprises a pressure vessel outlet nozzle and a pressure vessel inlet nozzle, the steam generator comprises a steam generator inlet nozzle and a steam generator outlet nozzle, the reactor coolant loop further comprises a main pipeline, the main pipeline comprises a hot section main pipeline connecting the pressure vessel outlet nozzle and the steam generator inlet nozzle, and a cold section main pipeline connecting the steam generator outlet nozzle and the pressure vessel inlet nozzle; Features: The steam generator inlet nozzle end face and the steam generator outlet nozzle end face are parallel to each other, the pressure vessel inlet nozzle end face and the pressure vessel outlet nozzle end face are perpendicular or parallel to each other, and the pressure vessel outlet nozzle end face is parallel to the steam generator inlet nozzle end face; and when the main pipeline of the reactor coolant loop is installed and welded, the welding positions of the four welds at both ends of the hot section main pipeline and the two ends of the cold section main pipeline are all horizontal fixed butt joints of the pipelines.

2. The reactor coolant loop according to claim 1, characterized in that: The reactor coolant loop further comprises a main pump, and the hot section main pipeline and / or the cold section main pipeline and the pump casing of the main pump are prefabricated into an integrated structure; Alternatively, the main pump is located at the bottom of the steam generator to obtain a steam generator with a main pump.

3. The reactor coolant loop according to claim 2, characterized in that: The attached main pump steam generator includes an inlet main pump and an outlet main pump, the inlet main pump includes an inlet main pump pump casing and an inlet main pump motor, the outlet main pump includes an outlet main pump pump casing and an outlet main pump motor, the impeller in the inlet main pump pump casing and the axial direction of the inlet main pump motor are parallel or perpendicular to the horizontal plane, and the impeller in the outlet main pump pump casing and the axial direction of the outlet main pump motor are perpendicular to the horizontal plane.

4. The reactor coolant loop according to any one of claims 1 to 3, characterized in that: The pipe end of the main pipeline is provided with an adjustment section.

5. The reactor coolant loop according to claim 2, characterized in that: During the installation of the reactor coolant loop, the equipment used includes a steam generator nozzle shadow body, and the steam generator nozzle shadow body includes two shadow nozzles corresponding to the steam generator inlet nozzle and the steam generator outlet nozzle respectively, and the end face dimensions and position dimensions of the two shadow nozzles are consistent with the dimensions of the corresponding nozzles of the steam generator.

6. The reactor coolant loop according to claim 5, characterized in that: The steam generator nozzle shadow body also includes a shadow body bottom head and a shadow table top, the shadow body bottom head corresponds to the bottom head of the steam generator, the shadow table top has the same size as the table top supporting the steam generator, and the steam generator nozzle shadow body is installed on the steam generator support through the shadow table top of the shadow body bottom head.

7. A method for installing a reactor coolant loop, characterized in that: For installing a reactor coolant loop according to any one of claims 1 to 6, the installation method comprises the following steps: A nozzle shadow manufacturing and installation step, manufacturing a steam generator nozzle shadow according to the steam generator, and installing the steam generator nozzle shadow on a steam generator support; a measuring and processing step, measuring and processing the adjustment section of the main pipeline end based on the shadow nozzle of the steam generator nozzle shadow body and the nozzle measurement data of the installed reactor pressure vessel; A post-processing step of introducing the measured processed main pipeline into an installation position; a nozzle shadow removal step, removing the steam generator nozzle shadow from the steam generator support; A steam generator installation step, introducing the steam generator into an installation position and placing it in place on the steam generator support; A nozzle main pipeline assembly pair installation step, wherein the steam generator nozzle, the pressure vessel nozzle and the main pipeline assembly are installed in pairs; Welding step: welding the weld between the nozzle and the main pipe.

8. The installation method according to claim 7, characterized in that: When the end face of the pressure vessel inlet nozzle and the end face of the pressure vessel outlet nozzle are perpendicular to each other, the installation method comprises the following steps: Before the measuring and processing step, the reactor pressure vessel and the hot section main pipeline are introduced into the installation position, and the weld between the outlet nozzle end face of the pressure vessel and the side end face of the hot section main pipeline pressure vessel is welded; In the measuring and processing step, after the side end face of the steam generator of the hot section main pipeline is paired with the inlet shadow nozzle of the steam generator nozzle shadow body, the adjustment section of the pipe end of the cold section main pipeline is measured and processed based on the measured data of the outlet shadow nozzle of the steam generator nozzle shadow body and the inlet nozzle of the pressure vessel and corrected according to the welding shrinkage amount of the inlet nozzle of the pressure vessel and the weld of the cold section main pipeline; After the post-processing positioning step, the two ends of the cold section main pipeline are respectively installed in pairs with the outlet shadow nozzle of the steam generator nozzle shadow body and the inlet nozzle of the pressure vessel, and the end face of the outlet shadow nozzle of the steam generator nozzle shadow body is offset from the end face of the cold section main pipeline by a welding shrinkage amount of the weld between the inlet nozzle of the pressure vessel and the cold section main pipeline.

9. The installation method according to claim 8, characterized in that: The installation method also includes the following steps: In the nozzle main pipeline assembly pair installation step, the end face of the steam generator outlet nozzle and the end face of the cold section main pipeline are offset by a welding shrinkage amount of the weld between the pressure vessel inlet nozzle and the cold section main pipeline; In the welding step, the weld between the pressure vessel inlet nozzle and the cold section main pipeline is welded first, and after the weld shrinks during welding, the end face of the steam generator outlet nozzle is aligned with the end face of the cold section main pipeline, and then the welds between the steam generator inlet nozzle and the hot section main pipeline, and between the steam generator outlet nozzle and the cold section main pipeline are welded simultaneously.

10. The installation method according to claim 7, characterized in that: Before the steam generator installation step, the main pipeline room and the steam generator room construction step are also included.

11. The installation method according to claim 7, characterized in that: When the end face of the pressure vessel inlet nozzle and the end face of the pressure vessel outlet nozzle are parallel to each other, the installation method comprises the following steps: In the measuring and processing step, the adjustment sections of the pipe ends of the hot section main pipe and the cold section main pipe are measured and processed respectively based on the shadow nozzle of the steam generator nozzle shadow body and the measurement data of the inlet and outlet nozzles of the reactor pressure vessel installed in place; in the nozzle main pipe pair installation step, the cold section main pipe and the hot section main pipe are first assembled and installed with the inlet and outlet nozzles of the reactor pressure vessel, and then the cold section main pipe and the hot section main pipe are assembled and installed with the inlet and outlet nozzles of the steam generator; in the welding step, the four welds between the pipe ends on both sides of the hot section main pipe and the cold section main pipe and the inlet and outlet nozzles of the reactor pressure vessel and the inlet and outlet nozzles of the steam generator are simultaneously and evenly welded.

Images