Water feeding pump device of header system boiler

Abstract

The utility model provides a header system boiler feed pump device, which relates to the technical field of power plant water supply devices, and comprises a plurality of water supply pipelines of feed pumps connected in parallel to a header pipe, the header pipe is connected with corresponding economizer assemblies through a plurality of branch pipes, and outlets of the economizer assemblies are connected with a steam pocket; a steam pocket pressure sensor is arranged at the top of the steam pocket; a water supply mother pipe pressure sensor is arranged on the mother pipe; the steam pocket pressure sensor and the water mother pipe pressure sensor are connected with the input end of the control assembly, and the output end of the control assembly is connected with the frequency converter. The technical problems that in the prior art, due to the fact that water feeding pumps are mutually independent, a water feeding adjusting door acts frequently, and energy is consumed are solved, frequent action of a valve is avoided, and throttling loss of the valve is reduced; the technical effects that multi-pump cooperative operation is achieved, and the main pipe pressure is stable when the water level of each steam pocket is independently adjusted are ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to power plant feedwater device technical field especially is a kind of mother-pipe system boiler feedwater pump device. BACKGROUND

[0002] Boiler is important energy conversion equipment, is widely used in electric power, chemical industry, heating and multiple fields. Among them, mother-pipe system boiler has the advantages of high equipment utilization, flexible operation, etc. In industrial production, it occupies an important position. Mother-pipe system boiler is a water supply system that two or more boilers share a pipeline for feedwater. In this system, the stable operation and efficient control of the feedwater pump play a key role in the safety and economy of the entire boiler system.

[0003] The existing mother-pipe system boiler feedwater structure mainly consists of a feedwater pump, a feedwater regulating valve, and a steam drum. The feedwater pump provides the power for the feedwater. The feedwater regulating valve controls the feedwater flow according to the steam drum water level requirement, thereby adjusting the steam drum water level. However, during operation, there is a lack of effective coordination mechanism between the various components. The feedwater pump pressure regulation and the steam drum water level regulation are independent of each other, and there is no close connection. When the steam drum water level changes, the feedwater pressure cannot be adjusted in time. For example, when the boiler load suddenly increases, the steam drum water level drops, and the feedwater regulating valve opens to increase the feedwater flow. However, the speed of the feedwater pump is not adjusted accordingly, causing fluctuations in the feedwater pressure.

[0004] Due to the lack of dynamic monitoring and precise control of pressure changes in the existing structure, the feedwater throttling loss is serious. The traditional feedwater regulation method relies on the throttling action of the feedwater regulating valve to control the flow. In this process, a large amount of pressure energy is converted into heat energy and wasted. Moreover, frequent throttling regulation causes the feedwater regulating valve to act frequently, which not only increases equipment wear and tear and shortens the service life of the valve, but also leads to additional energy consumption. SUMMARY

[0005] The utility model aims to provide a mother-pipe system boiler feedwater pump device to alleviate the technical problems of frequent action of feedwater regulating valve and energy consumption caused by independent feedwater pumps in the prior art.

[0006] The utility model provides a mother-pipe system boiler feedwater pump device, comprising: a feedwater pump, a mother pipe, a branch pipe, a coal economizer assembly, a steam drum, a steam drum pressure sensor, a feedwater mother pipe pressure sensor, a control assembly, and a frequency converter.

[0007] The feedwater pipelines of multiple feedwater pumps are connected in parallel to the main pipe. The main pipe is connected to the corresponding economizer components through multiple branch pipes. The outlet of the economizer components is connected to the steam drum. A steam drum pressure sensor is installed on the top of the steam drum, and a feedwater main pipe pressure sensor is installed on the main pipe. The steam drum pressure sensor and the feedwater main pipe pressure sensor are connected to the input terminal of the control component, and the output terminal of the control component is connected to the frequency converter.

[0008] Furthermore, the control components include a difference calculation module and a PID controller module;

[0009] The steam drum pressure sensor and the feedwater header pressure sensor are connected to the input of the differential calculation module, and the output of the differential calculation module is connected to the input of the PID controller module. The output of the PID controller module is connected to the frequency converter to control the feedwater pump speed.

[0010] Furthermore, a water supply valve is installed on the main pipe; manual valves are also installed on the pipelines where multiple water supply pumps are connected in parallel with the main pipe.

[0011] Furthermore, the economizer assembly includes a connected economizer inlet header and an economizer outlet header;

[0012] The economizer inlet header is connected to the branch pipe, and the economizer outlet header is connected to the steam drum.

[0013] Furthermore, the steam drum is connected to the inlet of the economizer outlet header via a downcomer.

[0014] Furthermore, the steam drum is equipped with multiple water level gauge interfaces, each with a water level gauge installed, and the water level gauge is electrically connected to the PID controller module.

[0015] Furthermore, a vibration sensor and a temperature sensor are installed on the pump body casing of the water pump, and both the vibration sensor and the temperature sensor are electrically connected to the PID controller module.

[0016] Furthermore, the frequency converter is electrically connected to the speed-regulating pumps in multiple water supply pumps.

[0017] Beneficial effects:

[0018] This utility model provides a main pipe boiler feedwater pump device, in which the feedwater pipes of multiple feedwater pumps are connected in parallel to the main pipe, and the main pipe is connected to the corresponding economizer assembly through multiple branch pipes. The outlet of the economizer assembly is connected to the steam drum. A steam drum pressure sensor is installed on the top of the steam drum, and a feedwater main pipe pressure sensor is installed on the main pipe. The steam drum pressure sensor and the feedwater main pipe pressure sensor are connected to the input end of the control component, and the output end of the control component is connected to the frequency converter.

[0019] Multiple feedwater pumps are connected in parallel to the main feedwater pipe to achieve coordinated operation. Each pump can operate flexibly according to system needs under the control of the control components, improving overall water supply efficiency, ensuring stable water supply to the boiler system, and avoiding problems such as uneven pressure and low efficiency of single pump operation. Pressure sensors in the steam drum and the feedwater main pipe monitor the pressure in real time, and the control components adjust the feedwater pump speed via frequency converters based on this information. When the flow rate changes due to independent water level adjustments in each steam drum, the system can respond quickly, maintaining stable pressure in the main pipe by adjusting the pump speed. This ensures that water level adjustments in each steam drum do not interfere with each other, guaranteeing stable operation of the entire boiler system and reducing equipment damage and failure risks caused by pressure fluctuations.

[0020] This invention also avoids pressure fluctuations caused by frequent valve operation, reduces the risk of sudden changes in steam drum water level, and extends the service life of valves and pump sets. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of the main pipe boiler feedwater pump device provided in this embodiment of the utility model;

[0023] Figure 2 A schematic diagram of the control components connection in the main pipe boiler feedwater pump device provided in this embodiment of the utility model.

[0024] Icons: 1 - Feedwater pump; 101 - Variable speed pump; 2 - Main pipe; 201 - Feedwater valve; 202 - Manual valve; 3 - Branch pipe; 4 - Economizer assembly; 401 - Economizer inlet header; 402 - Economizer outlet header; 5 - Steam drum; 6 - Steam drum pressure sensor; 7 - Feedwater main pipe pressure sensor; 8 - Control components; 801 - Differential calculation module; 802 - PID controller module; 9 - Frequency converter. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0032] like Figure 1 , Figure 2As shown, this utility model provides a main pipe boiler feedwater pump device, including: feedwater pump 1, main pipe 2, branch pipe 3, economizer assembly 4, steam drum 5, steam drum pressure sensor 6, feedwater main pipe pressure sensor 7, control assembly 8 and frequency converter 9.

[0033] Multiple feedwater pumps 1 have their feedwater pipes connected in parallel to the main pipe 2. The main pipe 2 is connected to the corresponding economizer assembly 4 through multiple branch pipes 3. The outlet of the economizer assembly 4 is connected to the steam drum 5.

[0034] A steam drum pressure sensor 6 is installed on the top of the steam drum 5, and a water supply main pipe pressure sensor 7 is installed on the main pipe 2; the steam drum pressure sensor 6 and the water supply main pipe pressure sensor 7 are connected to the input end of the control component 8, and the output end of the control component 8 is connected to the frequency converter 9.

[0035] Specifically, multiple feedwater pumps 1 are connected in parallel to the main pipe 2. The outlet pipes of each feedwater pump 1 are connected to the main pipe 2 via specialized connecting fittings, either by welding or flange connection. Multiple branch pipes 3 are led out from the main pipe 2 at appropriate locations via tee fittings. The connection between the branch pipes 3 and the main pipe 2 must be airtight to prevent water leakage and ensure that each branch pipe 3 receives water evenly from the main pipe 2. The end of the branch pipe 3 is connected to the economizer inlet header 401 in the economizer assembly 4. The connection method is welding or sealed threaded connection to ensure that the connection can withstand the pressure and temperature during economizer operation, allowing water from the main pipe 2 to smoothly enter the economizer assembly 4 for preheating. The outlet of the economizer assembly 4, i.e., the economizer outlet header 402, is connected to the steam drum 5 via a pipe. This connecting pipe must have high temperature and high pressure resistance, and the connection parts must use reliable welding technology to ensure the safe delivery of water preheated by the economizer to the steam drum 5. The steam drum pressure sensor 6 is installed at the center of the top of the steam drum 5 and is securely fixed to the steam drum 5 using a mounting bracket. The connection between the mounting bracket and the steam drum 5 is sealed to prevent steam leakage from affecting measurement accuracy. The steam drum pressure sensor 6 can directly and accurately measure the steam pressure inside the steam drum 5. The feedwater header pressure sensor 7 is installed on the straight section of the header 2, away from bends, valves, and other areas prone to water flow disturbance. It is connected to the header 2 via a threaded connection or a welded mounting bracket to ensure that the measured pressure is the stable water flow pressure inside the header 2.

[0036] The steam drum pressure sensor 6 and the feedwater main pipe pressure sensor 7 are connected to the input terminal of the control component 8 via signal transmission lines. Shielded cables are used in the signal transmission lines to prevent signal interference. The output terminal of the control component 8 is connected to the frequency converter 9 via a control cable to ensure accurate transmission of control commands.

[0037] Multiple feedwater pumps 1 are connected in parallel to the main pipe 2, enabling coordinated operation of multiple pumps. Under varying load demands, the speed of feedwater pumps 1 can be flexibly adjusted to ensure a stable and sufficient water supply, improving the reliability and efficiency of the entire boiler feedwater system. For example, during high-load boiler operation, more feedwater pumps 1 can be started or their speed increased to meet the large water demand; during low-load operation, the number of operating pumps or their speed can be reduced accordingly to avoid energy waste.

[0038] Steam drum pressure sensor 6 and feedwater header pressure sensor 7 monitor the pressure in real time and feed the data back to control component 8. Based on the sensor data, control component 8 calculates and adjusts the speed of feedwater pump 1 via frequency converter 9. When the pressure in steam drum 5 changes, such as when the steam load demand in steam drum 5 increases, and steam drum pressure sensor 6 detects a pressure increase, control component 8 quickly determines the direction and controls frequency converter 9 to increase the speed of feedwater pump 1, thereby increasing the feedwater flow to meet the water requirements for steam generation. Conversely, if the steam drum pressure decreases, control component 8 controls frequency converter 9 to decrease the speed of feedwater pump 1, reducing the feedwater flow.

[0039] When the pressure in main pipe 2 fluctuates, the system can also respond quickly. If the pressure in main pipe 2 increases, it indicates that the water supply capacity is relatively excessive, and the control component 8 will control the frequency converter 9 to reduce the speed of the water supply pump 1, thereby reducing the water supply; if the pressure in main pipe 2 decreases, the control component 8 will control the frequency converter 9 to increase the speed of the water supply pump 1, thereby increasing the water supply. In this way, the system can quickly and accurately adjust the speed of the water supply pump 1 to maintain the stability of the pressure in main pipe 2.

[0040] Throughout the adjustment process, frequent valve actuation is avoided. Because the speed adjustment of feedwater pump 1 can quickly and effectively meet the system's water volume and pressure requirements, frequent valve throttling is unnecessary. This significantly reduces valve throttling losses, lowering energy consumption and extending valve lifespan. For example, in traditional systems, valves may need to actuate dozens or even hundreds of times per hour. In this invention, due to the reduced number of valve actuations, system pressure fluctuations are effectively suppressed, ensuring that each steam drum 5 can independently adjust its water level without pressure interference. This ensures safe and stable boiler operation and improves boiler efficiency and reliability.

[0041] In an embodiment of this utility model, the control component 8 includes a difference calculation module 801 and a PID controller module 802;

[0042] The steam drum pressure sensor 6 and the feedwater header pressure sensor 7 are connected to the input terminal of the differential calculation module 801. The output terminal of the differential calculation module 801 is connected to the input terminal of the PID controller module 802. The output terminal of the PID controller module 802 is connected to the frequency converter 9 to control the speed of the feedwater pump 1.

[0043] Specifically, the signal output terminals of the steam drum pressure sensor 6 and the feedwater header pressure sensor 7 are connected to the input terminals of the differential calculation module 801 via shielded signal lines. The shielded signal lines effectively reduce external electromagnetic interference, ensuring accurate and stable transmission of pressure data to the differential calculation module 801. The output terminal of the differential calculation module 801 (e.g., differential pressure = header pressure - steam drum pressure) is connected to the input terminal of the PID controller module 802 via an internal data bus. This allows the difference between the steam drum pressure and the feedwater header pressure obtained by the differential calculation module 801 to be smoothly transmitted to the PID controller module 802, providing key input parameters for the PID controller module 802's calculations, enabling the PID controller module 802 to implement control strategies based on the pressure difference deviation. The output terminal of the PID controller module 802 is connected to the frequency converter 9 via a control cable, sending control commands to the frequency converter 9 to control the frequency converter 9 and thereby adjust the speed of the feedwater pump 1.

[0044] It should be noted that, based on the total boiler load and drum water level requirements, the differential setpoint (e.g., differential pressure = main pipe pressure - drum pressure) is dynamically calculated through an optimized algorithm to ensure that safety margins are met under different operating conditions. State-space predictive control and other algorithms are employed to incorporate parameters such as the flow rate, speed, and efficiency of the speed-regulating pump 101 on feedwater pump 1 into a multivariate coupled model, achieving rapid response and anti-interference capabilities for differential control (e.g., when the pressure in drum 5 rises due to combustion fluctuations, the algorithm automatically increases the speed of feedwater pump 1 to maintain the set differential, avoiding valve adjustment requirements caused by a passive increase in the pressure in main pipe 2). The real-time pressure difference and the speed-regulating pump operating parameters are fed back to the control algorithm to dynamically correct the speed command, avoiding overshoot or undershoot problems; closed-loop control is achieved through the DCS system.

[0045] It replaces traditional manual or single-variable control modes, enabling multi-pump coordinated operation and reducing operational intensity. Single boiler operation: The speed of a single feedwater pump 1 is directly controlled via frequency converter 9 to maintain a constant differential pressure. Multiple boilers operating in parallel: A pressure difference-flow decoupling algorithm is used to coordinate the speed distribution of multiple speed-regulating pumps 101, ensuring stable pressure in the main pipe 2 when each boiler drum 5 independently adjusts its water level.

[0046] In an embodiment of this utility model, a water supply valve 201 is provided on the main pipe 2; a manual valve 202 is also provided on the pipeline in parallel with the main pipe 2 for multiple water supply pumps 1.

[0047] Specifically, the water supply valve 201 (electric) is installed on the main pipe 2, positioned in a straight section of the pipe for easy operation and maintenance, and as close as possible to the connection area between the main pipe 2 and the water supply pump 1, facilitating centralized control of the water flow within the main pipe 2. The water supply valve 201 is tightly connected to the main pipe 2 via flange connection or welding. Each outlet pipe of the multiple water supply pumps 1 is equipped with a manual valve 202 on its parallel connection line with the main pipe 2.

[0048] Feedwater valve 201 and manual valve 202 serve as backup valves, playing a crucial role in the event of sudden system failures. For example, if the frequency converter 9 or control component 8 of feedwater pump 1 malfunctions, preventing automatic adjustment of the pump's speed, manual valve 202 can be manually operated to adjust the feedwater flow rate based on experience or site conditions, maintaining basic boiler operation. Feedwater valve 201, on the other hand, can be quickly closed in emergencies such as abnormal pressure fluctuations or pipe ruptures in the main pipe 2, cutting off water flow, preventing further escalation of the accident, and ensuring the safety of the entire system.

[0049] In an embodiment of this utility model, the economizer assembly 4 includes an economizer inlet header 401 and an economizer outlet header 402 connected together.

[0050] The economizer inlet header 401 is connected to the branch pipe 3, and the economizer outlet header 402 is connected to the steam drum 5.

[0051] The steam drum 5 is connected to the inlet of the economizer outlet header 402 via a downcomer.

[0052] Specifically, the economizer inlet header 401 is located at the water inlet end of the economizer assembly 4, and its connection to the branch pipe 3 is achieved through welding or flange connection. To ensure uniform water flow into the economizer assembly 4, the branch pipe 3, when connected to the economizer inlet header 401, will have connection points evenly distributed on the header according to the header's structure and water flow distribution requirements. The steam drum 5 is connected to the inlet of the economizer outlet header 402 via a downcomer. The downcomer is generally installed at the bottom of the steam drum 5, with the connection point located on the bottom of the steam drum 5 near the economizer outlet header 402. The connection between the downcomer and the steam drum 5 is achieved through welding or expansion joints to ensure a firm and sealed connection.

[0053] The connection between the economizer inlet header 401 and the branch pipe 3 ensures a uniform water flow distribution into the economizer assembly 4, allowing full utilization of the heat exchange surfaces within the economizer. The connection between the economizer outlet header 402 and the steam drum 5 ensures that the heated working fluid can enter the steam drum 5 in a timely manner, providing sufficient heat for steam generation.

[0054] In an embodiment of this utility model, the steam drum 5 is provided with multiple water level gauge interfaces, and a water level gauge is installed at each water level gauge interface. The water level gauge is electrically connected to the PID controller module 802.

[0055] Vibration sensors and temperature sensors are installed on the pump body casing of water pump 1. Both vibration sensors and temperature sensors are electrically connected to PID controller module 802.

[0056] The frequency converter 9 is electrically connected to the speed regulating pump 101 of the multiple water supply pumps 1.

[0057] Specifically, multiple water level gauge interfaces are distributed on the wall of the steam drum 5. These interfaces connect to the interior of the steam drum 5 and are used to install water level gauges. The water level gauges are tightly installed at the interfaces using mounting devices to ensure a good seal at the connection and prevent steam or water leakage from the steam drum. The water level gauges are electrically connected to the PID controller module 802 via signal lines. Multiple water level gauges installed on the steam drum 5 monitor the steam drum water level from different locations, improving the accuracy and reliability of water level monitoring. The water level gauges transmit real-time water level data to the PID controller module 802. Based on this data and parameters such as the steam drum pressure and the pressure difference between the feedwater header and the feedwater pump, the PID controller module 802 precisely controls the speed of the feedwater pump 1, thereby adjusting the feedwater flow in a timely manner and maintaining the water level in the steam drum 5 within a reasonable range.

[0058] Vibration and temperature sensors are installed on the pump casing of water pump 1, in locations that effectively monitor the pump's operating status, such as near the pump bearing housing or in critical parts of the pump casing. They are electrically connected to the PID controller module 802 via signal lines. This allows for real-time monitoring of the operating status of water pump 1.

[0059] Inverter 9 and Speed-Regulating Pump 101: Inverter 9 is connected to the speed-regulating pump 101 among the multiple feedwater pumps 1 via a power cable. During connection, the output terminal of inverter 9 is connected to the motor input terminal of speed-regulating pump 101, enabling inverter 9 to control the speed of speed-regulating pump 101. This allows the PID controller module 802 to precisely adjust the speed of speed-regulating pump 101 based on system pressure difference and other operating parameters via inverter 9. When the boiler load changes, the speed of speed-regulating pump 101 can be adjusted promptly, matching the flow rate and pressure of feedwater pump 1 with the actual needs of the boiler. Compared to traditional valve throttling regulation, this significantly reduces throttling losses, lowers motor power consumption, achieves energy saving and consumption reduction, and improves the energy utilization efficiency of the entire main pipe 2-controlled boiler system.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A boiler feedwater pump device with a main control system, characterized in that, include: Feedwater pump (1), main pipe (2), branch pipe (3), economizer assembly (4), steam drum (5), steam drum pressure sensor (6), feedwater main pipe pressure sensor (7), control assembly (8) and frequency converter (9); The feedwater pipes of multiple feedwater pumps (1) are connected in parallel to the main pipe (2), and the main pipe (2) is connected to the corresponding economizer assembly (4) through multiple branch pipes (3). The outlet of the economizer assembly (4) is connected to the steam drum (5). The steam drum pressure sensor (6) is installed on the top of the steam drum (5), and the water supply main pipe pressure sensor (7) is installed on the main pipe (2); the steam drum pressure sensor (6) and the water supply main pipe pressure sensor (7) are connected to the input end of the control component (8), and the output end of the control component (8) is connected to the frequency converter (9).

2. The boiler feedwater pump device according to claim 1, characterized in that, The control component (8) includes a difference calculation module (801) and a PID controller module (802); The steam drum pressure sensor (6) and the water supply main pipe pressure sensor (7) are connected to the input terminal of the difference calculation module (801), and the output terminal of the difference calculation module (801) is connected to the input terminal of the PID controller module (802); the output terminal of the PID controller module (802) is connected to the frequency converter (9) for controlling the speed of the water supply pump (1).

3. The boiler feedwater pump device according to claim 1, characterized in that, A water supply valve (201) is provided on the main pipe (2); a manual valve (202) is also provided on the pipeline in parallel with the main pipe (2) for multiple water supply pumps (1).

4. The boiler feedwater pump device according to claim 1, characterized in that, The economizer assembly (4) includes an economizer inlet header (401) and an economizer outlet header (402) connected together; The economizer inlet header (401) is connected to the branch pipe (3), and the economizer outlet header (402) is connected to the steam drum (5).

5. The boiler feedwater pump device according to claim 4, characterized in that, The steam drum (5) is connected to the inlet of the economizer outlet header (402) via a downcomer.

6. The boiler feedwater pump device according to claim 2, characterized in that, The steam drum (5) is provided with multiple water level gauge interfaces, and a water level gauge is installed at each water level gauge interface. The water level gauge is electrically connected to the PID controller module (802).

7. The boiler feedwater pump device according to claim 2, characterized in that, The water pump (1) is equipped with a vibration sensor and a temperature sensor on its pump body casing. Both the vibration sensor and the temperature sensor are electrically connected to the PID controller module (802).

8. The boiler feedwater pump device according to claim 1, characterized in that, The frequency converter (9) is electrically connected to the speed regulating pump (101) of the multiple water supply pumps (1).

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