Main feed pump set modular system and steam turbine generator plant

Abstract

The invention relates to the field of nuclear power plants, and discloses a main water feeding pump set modularization system and a steam turbine generator plant, multiple main water feeding pump sets are arranged in a modularization mode, structural integration, unified arrangement and function collaboration are achieved, and the design efficiency and operation reliability of a main water feeding system of the nuclear power plant are improved. The system comprises a plurality of main water feeding pump sets, the main water feeding pump sets are arranged on the bottom layer of a steam turbine generator plant deoxygenization room in the axial direction of a steam turbine generator, each main water feeding pump set comprises a booster pump, a motor, a hydraulic coupler and a main pump which are sequentially coupled, and the booster pumps are connected with the main pumps through medium-pressure water feeding pipelines. The booster pump is configured to increase the pressure of an inlet of the main pump in advance to prevent the cavitation phenomenon, the hydraulic coupler is configured to transmit the rotating speed of the motor to the main pump to adjust the rotating speed of the main pump, and the main pump is configured to sequentially send feed water in the deaerator in the deaeration room into all stages of high-pressure heaters and finally send the feed water into the nuclear island steam generator.

Description

Technical Field

[0001] The present application relates to the field of nuclear power plants, and particularly to a modular system for a main feed pump group and a steam turbine generator plant. Background Art

[0002] In the prior art, each main feed pump unit in the conventional island of a nuclear power plant is often independently arranged as multiple scattered devices, and there is a lack of a unified integrated combination method between their structures. Related equipment, pipelines, foundations, and auxiliary lifting devices are usually scattered on site, and a modular pump group with structural integrity and functional encapsulation is not formed. Especially in the case of multi-pump configurations, the existing systems usually do not have the ability to arrange in a grouped combination, which is not conducive to realizing the unified coordinated installation arrangement and functional cooperation of the equipment.

[0003] In view of this, there is an urgent need to propose a modular system for a main feed pump group that is structurally compact, functionally integrated, and suitable for overall arrangement to meet the requirements of the grouped and modular development of the nuclear power main feed water system. Summary of the Invention

[0004] The purpose of the present application is to provide a modular system for a main feed pump group and a steam turbine generator plant. By modularly arranging multiple main feed pump groups, structural integration, unified arrangement, and functional cooperation are achieved, improving the design efficiency and operation reliability of the main feed water system of the nuclear power plant.

[0005] The present application discloses a modular system for a main feed pump group, including: a plurality of main feed pump groups, which are arranged in sequence along the axial direction of the steam turbine generator in the bottom layer of the deaerator room of the steam turbine generator plant. Each main feed pump group includes a booster pump, a motor, a hydraulic coupling, and a main pump that are coupled in sequence, and the booster pump is connected to the main pump through a medium-pressure feed water pipeline;

[0006] The booster pump is configured to pre-increase the pressure at the inlet of the main pump to prevent the occurrence of cavitation. The hydraulic coupling is configured to transfer the rotational speed of the motor to the main pump to adjust the rotational speed of the main pump. The main pump is configured to sequentially send the feed water in the deaerator in the deaerator room into each stage of high-pressure heaters and finally into the nuclear island steam generator.

[0007] In a preferred example, a pre-stage medium-pressure feed water pipeline is provided on the medium-pressure feed water pipeline. The pre-stage medium-pressure feed water pipeline is a branch flow path of the medium-pressure feed water pipeline and is configured to guide the liquid in the medium-pressure feed water pipeline to drain during shutdown maintenance.

[0008] In a preferred example, the hydraulic coupling includes:

[0009] An input end for coupling with the output shaft of the booster pump through the motor;

[0010] An output end, which is used to be coupled with the input end of the main pump through a coupling;

[0011] A working chamber, which is arranged between the input end and the output end and is used to accommodate power liquid;

[0012] An impeller, which is arranged at the input end and rotates with the input end to drive the power liquid to flow;

[0013] A turbine, which is arranged at the output end and performs torque transmission with the impeller through the flow power of the power liquid;

[0014] A housing, which is used to enclose the working chamber and support the impeller and the turbine.

[0015] In a preferred example, a corresponding deep foundation pit is arranged below each main feed pump group, a plurality of anchor bolt holes are arranged in the deep foundation pit, and the bottom of the main feed pump group is fixed in the deep foundation pit through secondary grouting of the anchor bolt holes.

[0016] In a preferred example, the booster pump and the main pump are driven by the same motor.

[0017] In a preferred example, the booster pump runs at a constant speed, and the main pump runs at a variable speed through the hydraulic coupling.

[0018] In a preferred example, a single-rail hoisting combination device is arranged above each main feed pump group, which is used to perform hoisting, maintenance and replacement operations on the booster pump, the motor, the hydraulic coupling and the main pump respectively. Each main feed pump group is arranged in alignment with the corresponding single-rail hoisting combination device. The single-rail hoisting combination device includes a horizontally arranged single-rail crane and a vertically arranged single-rail crane.

[0019] In a preferred example, the deaerator in the deaeration chamber of the steam turbine generator plant is fluidly connected to the main feed pump modular system. The water outlet end of the deaerator is respectively sent into the inlet end of each main feed pump group through the inlet main pipe, and the outlet end of the main feed pump group is sequentially sent into each stage of high-pressure heaters through the outlet main pipe.

[0020] In a preferred example, a medium-pressure feed water pipe filter is arranged on the feed water pipe of each main feed pump group. The medium-pressure feed water pipe filter is used to intercept impurity particles in the main feed water. A differential pressure monitoring device is connected before and after the medium-pressure feed water pipe filter. The differential pressure monitoring device is used to monitor the differential pressure at both ends of the medium-pressure feed water pipe filter in real time to judge whether the medium-pressure feed water pipe filter is blocked and send an alarm signal to the upper-level system.

[0021] This application also discloses a steam turbine generator plant, which includes the main feed pump group modular system described above.

[0022] In the embodiments of the present application, by integrating multiple main feed pump groups into a compact module unit and arranging them axially along the steam turbine generator, the integration degree and space utilization rate of the system are significantly improved. Each main feed pump group consists of a booster pump, a motor, a hydraulic coupling, and a main pump, adopting a unified connection structure and speed regulation mechanism, which solves the problems of scattered arrangement of each device and lack of overall coordination in the prior art. By increasing the inlet pressure of the main pump through the booster pump, cavitation can be effectively prevented, and the hydraulic coupling realizes smooth speed regulation, ensuring the stability and reliability of the entire system during efficient operation. This design not only simplifies the installation and maintenance of equipment, but also reduces the cross-layout of pipelines and equipment in the system through integrated layout, improving the space utilization efficiency and the safety of system operation, and fundamentally solving the problems of poor coordination, equipment redundancy, and large floor area existing in the layout of traditional main feed pump groups.

[0023] Furthermore, the setting of the pre-positioned medium-pressure feed water pipeline can guide the liquid in the medium-pressure feed water pipeline to drain during shutdown maintenance, avoiding the problems of liquid retention and uneven pressure in the pipeline, and ensuring a safer and more efficient maintenance process. The hydraulic coupling adopts an efficient torque transmission method, coupling with the booster pump at the input end and the main pump at the output end. The flow of the power liquid in the working chamber drives the torque transmission between the pump impeller and the turbine, enhancing the speed regulation ability and operation smoothness of the system.

[0024] Furthermore, the main feed pump group is fixed through a deep foundation pit and anchor bolt holes, ensuring the stability of the system and the reliability of long-term operation. The single-rail hoisting combination device set above each pump group makes the installation, maintenance, and replacement operations of the equipment more convenient and efficient through the hoisting methods arranged horizontally and longitudinally. The feed water pipeline of the entire system is also provided with a filter screen and a differential pressure monitoring device, which can monitor the working state of the filter screen in real time. Once a blockage phenomenon is found, an alarm signal can be sent to the upper system in time, further improving the self-diagnosis ability and operation safety of the system.

[0025] Furthermore, the design of the modular system of the main feed pump group not only optimizes the functions and operability of the equipment, but also significantly improves the efficiency of engineering design and construction. The modular structure enables each component to be prefabricated in the factory and standardized interface design, greatly simplifying the on-site information provision and installation process. Through the standardized layout and connection form, each module of the system can be assembled and adjusted quickly and flexibly, reducing the on-site commissioning and installation time, and at the same time reducing the additional costs brought by on-site design changes. In addition, the hoisting combination device of the equipment and the unified foundation installation method also make the maintenance and replacement operations of the equipment more convenient, further improving the efficiency of later operation and maintenance.

[0026] A large number of technical features are described in the specification of this application, which are distributed in various technical solutions. If all possible combinations of technical features (i.e., technical solutions) of this application are listed, the specification will become overly lengthy. To avoid this problem, each technical feature disclosed in the above-mentioned invention content of this application, each technical feature disclosed in the following embodiments and examples, and each technical feature disclosed in the drawings can be freely combined with each other to form various new technical solutions (all of these technical solutions shall be regarded as having been described in this specification), unless the combination of such technical features is technically infeasible. For example, in one example, features A + B + C are disclosed, and in another example, features A + B + D + E are disclosed. Features C and D are equivalent technical means that perform the same function, and only one of them can be used technically and it is impossible to use both at the same time. Feature E can be combined with feature C technically. Then, the solution of A + B + C + D should not be regarded as having been described due to technical infeasibility, while the solution of A + B + C + E should be regarded as having been described. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the piping and instrumentation flow of the main feed pump group modular system according to an embodiment of the present application.

[0028] Figure 2 is a two-dimensional layout diagram of one main feed pump group according to an embodiment of the present application.

[0029] Figure 3 is a two-dimensional layout diagram of multiple main feed pump groups according to an embodiment of the present application.

[0030] Figure 4 is a civil engineering diagram of multiple main feed pump groups according to an embodiment of the present application.

[0031] Figure 5 is a civil engineering diagram of multiple main feed pump groups according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] In the following description, many technical details are provided to help the reader better understand the present application. However, those of ordinary skill in the art can understand that the technical solutions claimed in the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0033] To make the objectives, technical solutions, and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0034] The first embodiment of the present application relates to a main feed pump group modular system, and its structural diagram is as Figures 1-5As shown, it includes:

[0035] Multiple main feed pump sets are arranged axially along the turbine generator in the bottom layer of the deaerator room in the turbine generator building. Each main feed pump set includes a booster pump, a motor, a hydraulic coupling, and a main pump that are coupled in sequence. The booster pump and the main pump are connected by a medium-pressure feed water pipeline. The booster pump is configured to pre-increase the pressure at the inlet of the main pump to prevent cavitation. The hydraulic coupling is configured to transfer the speed of the motor to the main pump to adjust the speed of the main pump. The main pump is configured to sequentially send the feed water in the deaerator in the deaerator room into each stage of high-pressure heaters and finally into the nuclear island steam generator.

[0036] In an optional embodiment, a pre-medium-pressure feed water pipeline is provided on the medium-pressure feed water pipeline. The pre-medium-pressure feed water pipeline is a branch flow path of the medium-pressure feed water pipeline and is configured to guide the liquid in the medium-pressure feed water pipeline to drain during shutdown maintenance. Optionally, the outlet end of the pre-medium-pressure feed water pipeline is connected to a drainage collecting pipe or a drainage well. The drainage collecting structure is arranged in the deep foundation pit or the plant sump where the main feed pump set is located and is used to centrally drain the residual liquid discharged from each pump set to avoid on-site water accumulation or equipment corrosion. Optionally, the pre-medium-pressure feed water pipeline adopts a detachable structure, including quick-install flanges, clamp connections, or quick connectors, etc., so that it can be closed or replaced when the drainage channel is not in use to adapt to pump set systems with different layout forms.

[0037] In an optional embodiment, the hydraulic coupler includes: an input end, an output end, a working chamber, an impeller, a turbine, and a housing. The input end is used to be coupled with the output shaft of the pre-pump through a motor. The output end is used to be coupled with the input end of the main pump through a coupling. The working chamber is arranged between the input end and the output end and is used to accommodate the power liquid. The impeller is arranged at the input end and rotates with the input end to drive the flow of the power liquid. The turbine is arranged at the output end and performs torque transmission with the impeller through the flow power of the power liquid. The housing is used to enclose the working chamber and support the impeller and the turbine. Optionally, the input end is arranged on one side of the hydraulic coupler, is connected to the output shaft of the motor through a mechanical coupling method, and forms a coaxial transmission structure with the pre-pump at the same time to ensure a compact layout of the entire pump set system in the axial direction. The output end is arranged on the side opposite to the input end and is connected to the input shaft of the main pump through a coupling, so as to realize the drive of the main pump. The working chamber is arranged between the input end and the output end, forms a sealed hydraulic transmission space, and is used to fill a certain volume of power liquid (such as transformer oil, special hydraulic oil, etc.). The energy transfer between the impeller and the turbine is completed in this space. The impeller is fixedly installed inside the input end and rotates with the input end to stir the power liquid in the working chamber at a high speed. The turbine is fixedly installed inside the output end, opposite to the impeller, and there is no rigid connection between it and the impeller. Instead, the torque transmission from the impeller to the turbine is realized through the centrifugal force and kinetic energy generated by the flow of the power liquid. In this structure, the rotation of the impeller throws the liquid out to form an annular flow field, and this flow field impacts the turbine blades to realize non-contact drive, with good buffering and soft start characteristics. The hydraulic coupler can also be provided with a liquid guide device or an adjustable guide vane device on the housing to adjust the circulation path and flow rate of the liquid in the working chamber, so as to realize the continuously adjustable output speed and meet the operation requirements of the main pump under different load conditions. The housing forms an overall closed structure, which not only provides a mechanical support function, but also can prevent the leakage of the power liquid and withstand the internal pressure change to ensure the operation stability of the hydraulic coupler.

[0038] In an optional embodiment, a corresponding deep foundation pit is provided below each main feed water pump group. The deep foundation pit is a concrete foundation structure customized according to the layout position of the main feed water pump group, and its bottom and side walls are cast with high-strength concrete, having good bearing capacity and structural rigidity. The size of the deep foundation pit is determined according to the length, width and weight of the main feed water pump group, and the structural design is carried out in combination with the vibration load, impact load and thermal expansion requirements generated during the operation of the pump group. Multiple anchor bolt holes are provided in the deep foundation pit, and the anchor bolt holes are arranged at the corresponding positions of the base of the main feed water pump group for the installation and positioning of the main feed water pump group. The anchor bolt holes are used for embedding anchor bolts during the installation process, or inserting anchor bolts into the reserved holes and performing post-anchoring to achieve precise fixation of the pump group. After the main feed water pump group is placed, the holes around the anchor bolts are grouted twice, and the grouting material is used to fill the gap between the main pump base and the concrete foundation to form a complete and tight contact surface, improving the connection rigidity and seismic resistance. High-strength non-shrink grouting material can be used for the secondary grouting to ensure the long-term stability of the grouting layer and avoid loosening or displacement caused by foundation settlement or thermal cycle. After the grouting is completed and cured to meet the strength requirements, the main feed water pump group can enter the trial operation stage. This installation structure not only improves the overall installation accuracy and operation stability of the pump group, but also facilitates the disassembly and repositioning of the equipment during subsequent maintenance, and is applicable to the nuclear power main feed water system with high-precision and high-reliability requirements.

[0039] In an optional embodiment, the booster pump and the main pump are driven by the same motor. Specifically, the motor is arranged between the booster pump and the main pump, and is directly rigidly connected to the booster pump at one end and connected to the main pump through a hydraulic coupling at the other end, forming an integrated drive structure. The booster pump is a constant-speed pump, rigidly connected to the motor output shaft, running at a constant speed, and is used to form a certain pre-boost pressure at the inlet of the main pump to prevent cavitation of the main pump under the high-lift water absorption condition. The main pump is connected to the motor through a hydraulic coupling, and the hydraulic coupling dynamically adjusts the output speed according to the operating conditions of the main pump to achieve the adaptive regulation of the main pump flow rate and the system load. To ensure the driving stability, the motor can adopt a double-shaft extension structure, connected to the booster pump through a coupling or a rigid connection at one end, and connected to the input end of the hydraulic coupling at the other end to drive the main pump. This layout method ensures the alignment accuracy of the overall axis of the pump group and reduces the risk of equipment failure caused by eccentric load or vibration.

[0040] In an optional embodiment, the booster pump runs at a constant speed, and the main pump runs at a variable speed through a hydraulic coupling. Optionally, during the start-up and shutdown process of the system, the booster pump can be started first to establish a positive-pressure water supply environment, and then the main pump adjusts its speed to enter the target flow state, realizing soft start and smooth pressure transition, avoiding abnormal conditions such as water hammer, and further ensuring the operation safety of the main feed water system.

[0041] In an alternative embodiment, a cooler can be provided outside the motor. Specifically, the cooler can be connected to the motor housing through a coolant circulation system. The working principle of the cooler is to absorb the heat on the surface of the motor housing through circulating coolant (such as water, oil or special coolant), and release the heat to the environment through a radiator or heat exchanger. The coolant of the cooler is connected to the cooling interface on the motor housing through a pipeline. When the coolant flows through the surface of the motor housing, it absorbs heat. After passing through the heat exchanger inside the cooler, it releases the heat to the environment and continuously flows through a water pump or pump circulation method. The cooler can adopt various types, including air-cooled coolers and liquid-cooled coolers. The specific selection depends on the operating environment of the system and the required cooling capacity. The air-cooled cooler forces air to flow through an external fan to take away heat and is suitable for general low-temperature environments. The liquid-cooled cooler exchanges heat with the motor through the flow of coolant and is suitable for higher-power or high-temperature environments, capable of providing stronger cooling effects.

[0042] In an alternative embodiment, a single-rail hoisting combination device is provided above each main feed pump group for respectively performing hoisting, maintenance, and replacement operations on the booster pump, motor, fluid coupling, and main pump. Each main feed pump group is arranged in alignment with the corresponding single-rail hoisting combination device. The single-rail hoisting combination device includes a horizontally arranged single-rail crane and a vertically arranged single-rail crane. As Figure 5 shown, the horizontally arranged single-rail crane is arranged along the axial direction of the main feed pump group and is located above the booster pump and the main pump. This single-rail crane slides in the horizontal direction through a rail system and can accurately align with the equipment hoisting point. It is mainly responsible for hoisting the booster pump and the main pump from the installation position to the designated storage area, or moving the equipment to the maintenance area for further operations during maintenance. The vertically arranged single-rail crane is arranged between the two horizontally arranged single-rail cranes of the same main water pump group. The vertically arranged single-rail crane is used to lift the motor and the fluid coupling to the designated storage area, or move the equipment to the maintenance area for further operations during maintenance. By arranging the horizontal and vertical single-rail cranes in a staggered manner, the hoisting system makes better use of space and avoids the possible space waste during single-direction hoisting. This arrangement makes the equipment hoisting operation more flexible and allows more operations to be completed in a limited space.

[0043] In an alternative embodiment, the deaerator in the deaeration room of the steam turbine generator plant is fluidly connected to the main feed pump modular system. The outlet end of the deaerator is respectively fed into the inlet end of each main feed pump group through the main inlet pipe, and the outlet end of the main feed pump group is successively fed into each stage of high-pressure heaters through the main outlet pipe.

[0044] In an optional embodiment, a medium-pressure feed water pipeline strainer is provided on the feed water pipeline of each main feed water pump group. The medium-pressure feed water pipeline strainer is used to intercept impurity particles in the main feed water. A differential pressure monitoring device is connected before and after the medium-pressure feed water pipeline strainer. The differential pressure monitoring device is used to monitor the differential pressure at both ends of the medium-pressure feed water pipeline strainer in real time to determine whether the medium-pressure feed water pipeline strainer is blocked and send an alarm signal to the upper system. Optionally, the pre-positioned medium-pressure feed water pipeline can form a cooperative structure with the medium-pressure feed water pipeline strainer, be located in the front section and / or the rear section of the strainer, and work in coordination with the differential pressure monitoring system to trigger the automatic liquid discharge logic when abnormal strainer differential pressure is detected or the system needs to be shut down for maintenance, thereby enhancing the fault response ability.

[0045] In order to better understand the technical solution of the present application, a specific example will be described below. The details listed in this example are mainly for easy understanding and do not limit the protection scope of the present application.

[0046] The present application provides a modular system for main feed water pump groups, which improves the system integration, installation convenience, operation efficiency, and maintenance convenience through modular design.

[0047] In this embodiment, the modular system for main feed water pump groups includes multiple main feed water pump groups, and each main feed water pump group is arranged along the axial direction of the bottom layer of the deaerator room in the turbine generator building. Each main feed water pump group includes a booster pump, a motor, a hydraulic coupling, and a main pump. The booster pump and the main pump are also tightly connected through a medium-pressure feed water pipeline. The main function of the booster pump is to provide a stable inlet pressure for the main pump, thereby preventing the occurrence of cavitation. The motor is connected to the main pump through a hydraulic coupling, and the output flow of the main pump is adjusted by adjusting the speed of the hydraulic coupling, so as to meet the feed water requirements of the steam generator in the nuclear power plant.

[0048] Specifically, the booster pump and the main pump are driven by the same motor. The booster pump operates at a constant speed in the whole system, and its task is to continuously provide the necessary inlet pressure for the main pump. The main pump adjusts its speed through a hydraulic coupling to adapt to the flow requirements under different load conditions. The hydraulic coupling is coupled to the output shaft of the booster pump at the input end, and the output end is connected to the input end of the main pump through a coupling. The working chamber is filled with power liquid, and the liquid flow between the pump impeller and the turbine completes the torque transmission to ensure the stable speed regulation of the main pump.

[0049] To ensure the high efficiency and stability of the system operation, a corresponding deep foundation pit is provided under each main feed water pump group. Multiple anchor bolt holes are provided in the deep foundation pit, and the bottom of the main pump group is fixed in the deep foundation pit through secondary grouting, which can effectively increase the stability of the system and prevent the equipment from shifting due to vibration or thermal expansion during operation.

[0050] Above each set of main feed pump sets, a single-rail hoisting combination device is provided, which includes single-rail cranes arranged horizontally and vertically. The horizontal single-rail crane is mainly used for the horizontal movement and positioning of equipment, while the vertical single-rail crane is used for the precise longitudinal installation of equipment. Through this staggered arrangement, the hoisting device can make the most of the space, improve the hoisting efficiency and accuracy, and the hoisting in different directions does not interfere with each other, ensuring the smooth progress of equipment installation, maintenance and replacement.

[0051] To improve the maintenance and repair efficiency of equipment, the system design also includes a pre-positioned medium-pressure feed water pipe, which serves as a branch flow path of the medium-pressure feed water pipe and is specifically used to guide the liquid discharge during the repair process to avoid liquid retention affecting subsequent operations. The pre-positioned medium-pressure feed water pipe controls the liquid flow through a regulating valve and avoids impacting other systems during the liquid discharge process. Its layout ensures efficient operation during equipment maintenance and does not affect the overall operation of the system.

[0052] In addition, a filter is provided on the medium-pressure feed water pipe of each set of main feed pump sets. This filter is used to intercept impurity particles in the main feed water to prevent them from entering the system and causing blockages. Pressure difference monitoring devices are equipped before and after the filter to monitor the working status of the filter in real time. When an abnormal pressure difference is detected, the system will send an alarm signal to remind the operator to perform maintenance, thus ensuring the long-term stable operation of the system.

[0053] This embodiment can effectively meet the high reliability and high safety requirements of the nuclear power plant for the main feed water system. Through modular design and standardized interfaces, the system can be quickly installed and debugged, and at the same time provides great convenience in later maintenance and repair.

[0054] The second embodiment of this application relates to a steam turbine generator plant, which includes the main feed pump set modular system as described in any of the above embodiments. The design of this steam turbine generator plant is based on the standard layout of the conventional island plant building, where the main feed pump set modular system is arranged at the bottom of the deaerator room. The steam turbine generator plant uses this modular-designed main feed pump set system to improve the operation efficiency, stability and maintenance convenience of the entire system.

[0055] The layout of the conventional island plant building is briefly introduced below. On the turbine front side, the bottom layer of the conventional island plant building is arranged with a main steam header, main steam pipes, bypass pipes and related drain devices. Two MSR drain pumps on both sides of the high-pressure cylinder and a vertical drain flash tank at the tail of the turbine are also provided in this area to ensure the effective drainage and stable operation of the main steam system. At the generator end, three vacuum pumps, an open water motor filter, a tubular water-water heat exchanger and a cooling water pump are arranged to ensure the normal cooling of the generator and maintain the operation of the equipment.

[0056] At the bottom floor of the deaerator room in the conventional island building, the start-up feed water pump, three main feed water pump sets and four vertical low-pressure heater drain pumps are specially arranged. Among them, the modular system of the main feed water pump sets occupies the core position and provides stable feed water supply for the entire steam turbine generator set. In order to meet the high-efficiency water supply demand and deal with equipment maintenance, the modular design of the pump sets enables the system to achieve rapid equipment replacement and maintenance.

[0057] On the middle floor and the operating floor of the conventional island building, the layout of other thermal energy management and auxiliary systems cooperates with the modular system of the main feed water pump sets. For example, on the middle floor of the turbine building, equipment such as the lubricating oil system of the steam turbine generator, the seal oil system of the generator, and the stator cooling water device of the generator are all closely related to the operation of the main feed water system to ensure the stable operation of the steam turbine and the generator. And on the middle floor of the deaerator room, the layout of the high-pressure heaters and low-pressure heaters provides additional heat exchange for the system, further improving the thermal efficiency and operating capacity of the system. The water supply, drain, cooling and heat exchange equipment of the entire modular system of the main feed water pump sets are integrated through standardized interfaces and a unified control system. As the core component of the entire water supply system, the modular system of the main feed water pump sets forms a close cooperation with other thermal energy management equipment in the conventional island building to achieve efficient water supply and heat energy utilization.

[0058] This embodiment includes the technical solutions in the first embodiment, and the technical details in the first embodiment can be applied to this embodiment.

[0059] It should be noted that in the application documents of this patent, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one" does not exclude the existence of another identical element in the process, method, article or device including the said element. In the application documents of this patent, if it is mentioned that an act is performed according to a certain element, it means at least performing the act according to the said element, including two cases: performing the act only according to the said element, and performing the act according to the said element and other elements. Expressions such as multiple, many times, various include 2, 2 times, 2 kinds, and more than 2, more than 2 times, more than 2 kinds.

[0060] All documents mentioned in this application are considered to be incorporated herein in their entirety for the purpose of providing a basis for modification if necessary. In addition, it should be understood that after reading the above disclosure of this application, those skilled in the art can make various changes or modifications to this application, and these equivalent forms also fall within the scope of protection claimed in this application.

Claims

1. A modular system of main feed water pump group, characterized in that: include: A plurality of main feed water pump groups, which are arranged along the axial direction of the steam turbine generator on the bottom floor of the deaerator room of the steam turbine generator plant, each of which comprises a pre-pump, a motor, a hydraulic coupler and a main pump coupled in sequence, and the pre-pump is connected to the main pump through a medium-pressure feed water pipeline; The pre-pump is configured to pre-increase the pressure at the inlet of the main pump to prevent the occurrence of cavitation. The hydraulic coupling is configured to transmit the rotation speed of the motor to the main pump to adjust the rotation speed of the main pump. The main pump is configured to send the feed water in the deaerator in the deaerator room to each stage of high-pressure heaters in sequence, and finally to the nuclear island steam generator.

2. The main feed water pump group modular system according to claim 1, characterized in that: The medium-pressure water supply pipeline is provided with a front medium-pressure water supply pipeline, which is a branch flow path of the medium-pressure water supply pipeline. The front medium-pressure water supply pipeline is configured to guide the liquid in the medium-pressure water supply pipeline to be discharged when the medium-pressure water supply pipeline is shut down for maintenance.

3. The main feed water pump group modular system according to claim 1, characterized in that: The hydraulic coupler comprises: An input end, used for coupling with an output shaft of a front pump through the motor; An output end, used for coupling with an input end of a main pump through a coupling; A working chamber, disposed between the input end and the output end, for containing a power liquid; A pump wheel, disposed at the input end and rotating with the input end to drive the power fluid to flow; a turbine, arranged at the output end, and transmitting torque with the pump wheel through the flow power of the power fluid; The outer shell is used to close the working chamber and support the pump wheel and the turbine.

4. The main feed water pump group modular system according to claim 1, characterized in that: A corresponding deep foundation pit is provided below each of the main water supply pump groups. A plurality of anchor bolt holes are provided in the deep foundation pit. The bottom of the main water supply pump group is fixed in the deep foundation pit by secondary grouting through the anchor bolt holes.

5. The main feed water pump group modular system according to claim 1, characterized in that: The pre-pump and the main pump are driven by the same motor.

6. The main feed water pump group modular system according to claim 1, characterized in that: The front pump moves at a constant speed, and the main pump moves at a speed controlled by the hydraulic coupler.

7. The main feed water pump group modular system according to claim 1, characterized in that: A monorail lifting assembly device is arranged above each group of the main water supply pump groups, which is used to perform lifting, maintenance and replacement operations on the pre-pump, the motor, the hydraulic coupling and the main pump respectively. Each group of the main water supply pump groups is aligned with the corresponding monorail lifting assembly device, and the monorail lifting assembly device includes a horizontally arranged monorail crane and a longitudinally arranged monorail crane.

8. The main feed water pump group modular system according to claim 1, characterized in that: The deaerator in the deaerator room of the steam turbine generator plant is fluidically connected to the main feed water pump modular system. The water outlet of the deaerator is respectively sent to the inlet of each group of the main feed water pump group through the water inlet main pipe, and the outlet of the main feed water pump group is sequentially sent to each level of high-pressure heater through the water outlet main pipe.

9. The main feed water pump group modular system according to claim 1, characterized in that: A medium-pressure water supply pipe filter is provided on the water supply pipe of each group of the main water supply pump groups. The medium-pressure water supply pipe filter is used to intercept foreign particles in the main water supply. A pressure difference monitoring device is connected before and after the medium-pressure water supply pipe filter. The pressure difference monitoring device is used to monitor the pressure difference at both ends of the medium-pressure water supply pipe filter in real time to determine whether the medium-pressure water supply pipe filter is blocked and send an alarm signal to the upper system.

10. A steam turbine generator plant, characterized in that: A modular system comprising a main feed water pump group as described in any one of claims 1-9.

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