Isolation method and isolation system of feed pump turbine

Abstract

The invention relates to an isolation method and an isolation system of a feed pump steam turbine, and belongs to the technical field of thermal power generating unit feed pumps, and the isolation method comprises the following steps: a, when the unit is reduced to 50% of BMCR load, the faulted feed pump steam turbine is shut down; b, checking tight closing of a steam inlet electrically operated gate and a control valve of the water feed pump; c, after the rotating speed of the water-feeding pump turbine is reduced to 0, a steam exhaust butterfly valve of the water-feeding pump turbine is closed; d, checking that the steam exhaust butterfly valve is completely closed in place, closing a drainage electrically operated gate in front of the steam exhaust butterfly valve, and powering off the electrically operated gate; e, a condenser vacuum pressure adjusting valve is opened, and the unit condenser vacuum is reduced to-90 kPa; f, unfastening a movable joint behind a primary door of a vacuum pressure transmitter of the water feed pump turbine, connecting a hose to a condensation pit, and monitoring the water level of an exhaust hood of the water feed pump; the system has the advantages that online isolation overhaul of the water feeding pump turbine is achieved, non-stop of a unit is avoided, and the safety and economic benefits of unit operation are enhanced.

Description

Technical Field

[0001] The invention relates to an isolation method and an isolation system for a feedwater pump steam turbine, belonging to the technical field of feedwater pumps for thermal power generation units. Background Art

[0002] In traditional thermal power plant operations, the fault handling of feedwater pump turbines usually involves the shutdown of the entire unit, which is particularly disadvantageous in the electricity spot market. Shutdowns for maintenance not only lead to a direct reduction in power generation, but may also result in fines for failure to meet contracted power supply. In addition, frequent shutdowns will also affect the competitiveness of power plants in the power market because it limits the power plant's ability to respond to market changes.

[0003] Another problem with shutdowns is the increase in maintenance costs. Each shutdown means additional manpower and material resources are required to restart the unit, which includes not only fuel costs, but also labor costs and equipment wear. In addition, shutdowns may also result in heat and pressure losses, which will increase the operating costs of the power plant.

[0004] Furthermore, shutdowns for maintenance also have a certain impact on the environment. Frequent start-ups and shutdowns of units will increase fuel consumption, thereby increasing emissions of greenhouse gases and other pollutants. As we pay more and more attention to environmental protection, this impact may be subject to more supervision and restrictions.

[0005] It is also reflected in the impact on equipment life. Frequent start and stop will bring additional mechanical stress to the steam turbine and other equipment, which may shorten the service life of the equipment and increase future maintenance and replacement costs.

[0006] In addition, traditional maintenance processes often lack flexibility. During peak electricity demand periods, unit shutdowns may cause tight electricity supply and even lead to instability in the power system. During low demand periods, unit shutdowns may not have much impact on the market, but will still cause unnecessary economic losses. Summary of the invention

[0007] In order to overcome the defects of the prior art, the present invention provides an isolation method and an isolation system for a feedwater pump turbine. The technical solution of the present invention is:

[0008] A method for isolating a feedwater pump turbine comprises the following steps:

[0009] a. When the unit is reduced to 50% BMCR load, shut down the faulty feedwater pump turbine;

[0010] b. Check that the steam inlet electric door and regulating valve of the water supply pump are closed tightly;

[0011] c. After the speed of the feedwater pump steam turbine drops to 0, close the feedwater pump steam turbine exhaust butterfly valve;

[0012] d. Check that the exhaust butterfly valve is fully closed, close the drain electric door in front of the exhaust butterfly valve, and cut off the power to the electric door;

[0013] e. Open the condenser vacuum pressure regulating valve to reduce the unit condenser vacuum to -90kPa;

[0014] f. Unlock the joint behind the primary door of the feedwater pump turbine vacuum pressure transmitter, connect the hose to the condensate pit, and monitor the water level of the feedwater pump discharge cylinder;

[0015] g. Insert the exhaust pipe spring bracket stop pin into the exhaust pipe and lock it to form a rigid support to prevent the turbine exhaust pipe from being overloaded and deformed during water injection;

[0016] h. Open the electric door for cooling water from the exhaust pipe of condensate to the feedwater pump turbine to inject water into the feedwater pump turbine;

[0017] i. Open the exhaust pipe of the feedwater pump turbine, lead out the stainless steel pipe to the exhaust pipe of the feedwater pump turbine, and add a manual door;

[0018] j. Open the manual valve for filling the water supply from the feedwater pump to the exhaust pipe of the feedwater pump, adjust the opening of the manual valve, and control the water level;

[0019] k. Test-stop the feedwater pump turbine shaft seal and check the condenser vacuum drop;

[0020] l. After the vacuum is stable, close the manual steam inlet and return doors of the feedwater pump turbine shaft seal;

[0021] m. After judging that the exhaust butterfly valve is tightly closed, the main engine vacuum is maintained stable, and the exhaust pressure reaches zero, open the cylinder for inspection.

[0022] In the step a, specifically:

[0023] a1. Load monitoring and adjustment: Before shutting down the feedwater pump turbine, first monitor the load of the entire power plant unit in real time to ensure that the current load has been reduced to below 50% BMCR;

[0024] a2. Fault diagnosis: Conduct detailed fault diagnosis on the feedwater pump turbine to confirm whether there is a fault, as well as the type and severity of the fault;

[0025] a3. Advance preparation: After confirming that the faulty feedwater pump turbine needs to be shut down, the operator needs to carry out advance preparation work, including but not limited to checking the status of the standby feedwater pump turbine to ensure that it can be started at any time to take over the work of the faulty unit; notifying relevant maintenance personnel and engineers to prepare maintenance tools and equipment; and preparing necessary safety measures and emergency plans;

[0026] a4. Shutdown operation: The operator will perform the shutdown operation, close the steam valve entering the feedwater pump turbine, cut off the steam supply, and reduce the load of the feedwater pump until it stops running completely;

[0027] a5. System isolation: After the feedwater pump turbine is shut down, the system is isolated, including closing all pipes and valves connected to the feedwater pump turbine to ensure that no medium continues to flow into or out of the feedwater pump turbine, so as to facilitate subsequent maintenance work;

[0028] a6. Safety inspection: After the shutdown and isolation operations are completed, conduct a safety inspection of the feedwater pump turbine and its surrounding areas to ensure that there are no leaks, overheating or other potential safety hazards;

[0029] a7. Records and reports: The operator needs to keep detailed records of the shutdown operation process and report to the superior management in order to arrange subsequent maintenance work and adjust the unit operation plan.

[0030] The step e is specifically as follows:

[0031] e1. Evaluate the current vacuum degree: Evaluate the current vacuum degree of the condenser, check the real-time vacuum reading of the condenser through the monitoring system, and ensure that it is within the normal operating range;

[0032] e2. Prepare the regulating equipment: ensure that the driving mechanism of the condenser vacuum pressure regulating door is in good condition; check the limit switch and position indicator of the regulating door to ensure that they accurately reflect the state of the regulating door;

[0033] e3. Open the regulating door: Open the condenser vacuum pressure regulating door to avoid the impact of rapid pressure changes on the unit; the regulating door is opened in stages, and the change of vacuum degree must be checked after each adjustment;

[0034] c4. Monitor vacuum changes: During the adjustment process, continuously monitor the vacuum gauge of the condenser to ensure that the vacuum changes meet expectations;

[0035] e5. Reach the target vacuum: Continue to fine-tune the regulating door until the vacuum of the condenser drops to -90kPa; once the target vacuum is reached, stabilize the door opening to ensure that the vacuum remains at the set value;

[0036] e6. Record the operation process: record the data during the operation, including the final opening of the regulating door, the change process of the condenser vacuum degree and the operation time;

[0037] e7. Notify subsequent operators: When the condenser vacuum stabilizes at -90kPa, notify subsequent operators to isolate and repair the feedwater pump turbine.

[0038] The step j is specifically as follows:

[0039] j1. Open the manual water injection door: Open the manual water injection door for the feedwater pump to inlet the sealing water to the exhaust pipe of the feedwater pump, and start injecting water into the exhaust pipe;

[0040] j2. Monitor water level changes: Use water level monitoring equipment to monitor water level changes in the exhaust pipe of the feedwater pump in real time;

[0041] j3. Adjust the opening of the manual door: adjust the opening of the manual door according to the water level monitoring results;

[0042] j4. Maintain a stable water level: adjust the opening of the manual door to keep the water level below the height of the feedwater pump turbine blades;

[0043] j5. Record operation data: record the start and end time of water injection, the opening degree of the manual door, and the change of water level.

[0044] The step m is specifically as follows:

[0045] m1 Measure the vacuum of the main engine: Use a vacuum monitoring instrument to monitor the vacuum status of the main engine in real time to ensure that there is no abnormal change in the vacuum degree of the main engine after the exhaust butterfly valve is closed;

[0046] m2. Check exhaust steam pressure: Check the pressure of the exhaust steam pipe through the pressure monitoring instrument to confirm that it has dropped to zero or close to zero pressure level;

[0047] m3. Stable vacuum degree: After the exhaust pressure drops to zero, continue to monitor the vacuum degree to ensure that it remains stable without fluctuation or decline;

[0048] m4. Cylinder opening operation: After confirming that all safety measures are in place, start the cylinder opening operation.

[0049] A feedwater pump turbine isolation system, comprising:

[0050] Speed ​​monitoring module, used to monitor the real-time speed of the feedwater pump turbine;

[0051] Vacuum monitoring module, used to monitor the vacuum degree of the unit condenser;

[0052] Water level monitoring module, used to monitor the water level of the discharge cylinder of the feedwater pump;

[0053] A water injection control module, used to control the water injection operation of the feedwater pump turbine;

[0054] The valve operation module is used to perform the opening and closing operations of the feedwater pump turbine exhaust butterfly valve and valve components.

[0055] The speed monitoring module speed sensor.

[0056] The vacuum monitoring module is a vacuum sensor.

[0057] The water level monitoring device is a water level sensor.

[0058] The water injection control device is a water injection valve connected to the exhaust pipe of the feedwater pump turbine; the valve operation module includes an electric actuator and a manual operating mechanism.

[0059] The advantages of the present invention are: achieving online isolation and maintenance of the feedwater pump turbine, avoiding unplanned shutdown of the unit, and enhancing the safety and economic benefits of the unit operation.

[0060] Improve safety: Reduce operational risks and ensure the safety of personnel and equipment through precise control and monitoring.

[0061] Reduce downtime: Realize online isolation, avoid the shutdown of the entire unit due to maintenance, and reduce downtime.

[0062] Improve efficiency: The automation module reduces the need for manual operations and improves operational efficiency and response speed.

[0063] Reduced costs: Reduced downtime and increased efficiency help reduce financial losses due to maintenance.

[0064] Environmentally friendly: Reduce fuel consumption and emissions caused by frequent starts and stops, which is more environmentally friendly.

[0065] Extend equipment life: Avoiding the extra stress on equipment caused by frequent starts and stops helps extend equipment life. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a schematic diagram of the main structure of the present invention. DETAILED DESCRIPTION

[0067] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, these embodiments are exemplary only and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of protection of the present invention.

[0068] See also Figure 1 The present invention relates to a method for isolating a feedwater pump turbine, comprising the following steps:

[0069] a. When the unit is reduced to 50% BMCR load, shut down the faulty feedwater pump turbine;

[0070] b. Check that the steam inlet electric door and regulating valve of the water feed pump are closed tightly;

[0071] c. After the speed of the feedwater pump steam turbine drops to 0, close the feedwater pump steam turbine exhaust butterfly valve;

[0072] d. Check on-site that the exhaust butterfly valve is fully closed, close the drain electric door in front of the exhaust butterfly valve, and cut off the power to the electric door;

[0073] e. Slightly open the condenser vacuum pressure regulating valve to reduce the unit condenser vacuum to -90kPa, which can reduce the vacuum leakage;

[0074] f. Unlock the joint behind the primary door of the feedwater pump turbine vacuum pressure transmitter, connect the hose to the condensate pit, monitor the water level of the feedwater pump discharge cylinder, and control the water level below the height of the feedwater pump turbine blades to prevent it from affecting the maintenance work;

[0075] g. Insert the exhaust pipe spring bracket stop pin into the exhaust pipe and lock it to form a rigid support to prevent the turbine exhaust pipe from being overloaded and deformed during water injection;

[0076] h. Open the electric door for cooling water of the exhaust pipe of condensate to the feedwater pump turbine to inject water into the feedwater pump turbine; realize temporary water seal of the exhaust butterfly valve to prevent the vacuum drop of the unit caused by the loose exhaust butterfly valve. Since the pipe is relatively thin (Φ20), the condensate pressure is only 1.5MPa, the water volume is small, and the water level cannot be maintained. It can only slow down the speed of vacuum drop, but it is convenient for the next step of opening the exhaust pipe of the feedwater pump turbine;

[0077] i. The exhaust pipe opening of the feedwater pump turbine is Φ50, and a Φ50 stainless steel pipe is led out to the exhaust pipe of the feedwater pump turbine, and a manual door is added. A rough pipe can use sealing water with a pressure of 2.7MPa. The water volume is sufficient to meet the sealing requirements of the exhaust butterfly valve;

[0078] j. Open the manual water injection valve for the feedwater pump's sealing water to flow into the feedwater pump's exhaust pipe, adjust the manual door opening, and control the water level; adjust the manual door opening according to the vacuum drop value to control the water level below the height of the feedwater pump's turbine blades. The vacuum starts at -90kPa, and the water level increases by 0.1 meters for every 1kPa drop. When the water level drops quickly, increase the water injection valve opening and increase the water replenishment. A balance is formed through the water replenishment and the leakage from the exhaust butterfly valve to the condenser to maintain a stable water level;

[0079] k. Test-stop the feedwater pump turbine shaft seal and check the condenser vacuum drop. When the vacuum drops, open the water injection gate. When the vacuum is stable, maintain the water level stable. The water level must not exceed the feedwater pump turbine blades. Control the condenser vacuum to above -85kPa;

[0080] l. After the vacuum is stable, close the manual steam inlet and return doors of the feedwater pump turbine shaft seal;

[0081] m. After judging that the exhaust butterfly valve is tightly closed, the main engine vacuum is stable, and the exhaust pressure reaches zero, the cylinder opening inspection work can be carried out. After the main engine vacuum is stable above -85kPa and the exhaust pressure reaches zero, loosen the bolts of the manhole door of the small engine exhaust cylinder, and further observe and test the main engine vacuum change from slightly open to fully open the manhole door. After confirming that it does not affect the opening of the cylinder, the cylinder opening inspection work can be carried out.

[0082] In the step a, specifically:

[0083] a1. Load monitoring and adjustment: Before shutting down the feedwater pump turbine, first monitor the load of the entire power plant unit in real time to ensure that the current load has been reduced to below 50% BMCR; this step is to ensure that when the feedwater pump turbine is shut down, it will not cause too much impact on the stable operation of the unit.

[0084] a2. Fault diagnosis: Conduct detailed fault diagnosis on the feedwater pump turbine to confirm whether there is a real fault, as well as the type and severity of the fault. This step is crucial to determine whether the feedwater pump turbine needs to be shut down;

[0085] a3. Advance preparation: After confirming that the faulty feedwater pump turbine needs to be shut down, the operator needs to carry out advance preparation work, including but not limited to checking the status of the standby feedwater pump turbine to ensure that it can be started at any time to take over the work of the faulty unit; notifying relevant maintenance personnel and engineers to prepare maintenance tools and equipment; and preparing necessary safety measures and emergency plans;

[0086] a4. Shutdown operation: The operator will perform the shutdown operation, close the steam valve entering the feedwater pump turbine, cut off the steam supply, and reduce the load of the feedwater pump until it stops running completely;

[0087] a5. System isolation: After shutting down the feedwater pump turbine, isolate the system, including closing all pipes and valves connected to the feedwater pump turbine to ensure that no medium (such as steam, water, etc.) continues to flow into or out of the feedwater pump turbine, so as to facilitate subsequent maintenance work.

[0088] a6. Safety inspection: After the shutdown and isolation operations are completed, conduct a safety inspection of the feedwater pump turbine and its surrounding areas to ensure that there are no leaks, overheating or other potential safety hazards;

[0089] a7. Records and reports: The operator needs to keep detailed records of the shutdown operation process and report to the superior management in order to arrange subsequent maintenance work and adjust the unit operation plan.

[0090] The step e is specifically as follows:

[0091] e1. Evaluate the current vacuum degree: Evaluate the current vacuum degree of the condenser, check the real-time vacuum reading of the condenser through the monitoring system, and ensure that it is within the normal operating range;

[0092] e2. Prepare the regulating equipment: ensure that the driving mechanism (such as electric or pneumatic actuator) of the condenser vacuum pressure regulating door is in good condition; check the limit switch and position indicator of the regulating door to ensure that they accurately reflect the state of the regulating door;

[0093] e3. Open the regulating door: Open the condenser vacuum pressure regulating door to avoid the impact of rapid pressure changes on the unit; the regulating door is opened in stages, and the change of vacuum degree must be checked after each adjustment;

[0094] c4. Monitor vacuum changes: During the adjustment process, continuously monitor the vacuum gauge of the condenser to ensure that the vacuum changes meet expectations;

[0095] e5. Reach the target vacuum: Continue to fine-tune the regulating door until the vacuum of the condenser drops to -90kPa; once the target vacuum is reached, stabilize the door opening to ensure that the vacuum remains at the set value;

[0096] e6. Record the operation process: record the data during the operation, including the final opening of the regulating door, the change process of the condenser vacuum degree and the operation time;

[0097] e7. Notify subsequent operators: When the condenser vacuum stabilizes at -90kPa, notify subsequent operators to isolate and repair the feedwater pump turbine.

[0098] The step j is specifically as follows:

[0099] j1. Open the manual water injection door: Open the manual water injection door for the feedwater pump to inlet the sealing water to the exhaust pipe of the feedwater pump, and start injecting water into the exhaust pipe;

[0100] j2. Monitor water level changes: Use water level monitoring equipment (such as water level gauge or sensor) to monitor water level changes in the exhaust pipe of the feedwater pump in real time;

[0101] j3. Adjust the opening of the manual door: According to the water level monitoring results, adjust the opening of the manual door. If the water level rises too fast, reduce the opening; if the water level rises too slowly, increase the opening.

[0102] j4. Maintain a stable water level: adjust the manual door opening to keep the water level below the height of the feed pump turbine blades to prevent it from affecting maintenance work; maintain a stable water injection rate to ensure that the water level does not rise too quickly due to excessive water injection.

[0103] j4. Record operation data: record the start and end time of water injection, the opening degree of the manual door, and the change of water level.

[0104] The step m is specifically as follows:

[0105] m1 Measure the vacuum of the main engine: Use a vacuum monitoring instrument to monitor the vacuum status of the main engine in real time to ensure that there is no abnormal change in the vacuum degree of the main engine after the exhaust butterfly valve is closed;

[0106] m2. Check exhaust steam pressure: Check the pressure of the exhaust steam pipe through the pressure monitoring instrument to confirm that it has dropped to zero or close to zero pressure level;

[0107] m3. Stable vacuum degree: After the exhaust pressure drops to zero, continue to monitor the vacuum degree to ensure that it remains stable without fluctuation or decline;

[0108] m4. Cylinder lifting operation: After confirming that all safety measures are in place, start the cylinder lifting operation. This usually includes loosening the cylinder fastening bolts, using a jack or other equipment to lift and remove the cylinder.

[0109] The present invention also relates to a feedwater pump steam turbine isolation system for implementing the isolation method, comprising: a speed monitoring module 1, for monitoring the real-time speed of the feedwater pump steam turbine;

[0110] Vacuum monitoring module 2, used to monitor the vacuum degree of the unit condenser;

[0111] Water level monitoring module 3, used to monitor the water level of the exhaust cylinder of the feedwater pump;

[0112] A water injection control module 4, used to control the water injection operation of the feedwater pump turbine;

[0113] The valve operation module 5 is used to perform the opening and closing operations of the exhaust butterfly valve and valve components of the feedwater pump turbine.

[0114] The speed monitoring module speed sensor.

[0115] The vacuum monitoring module is a vacuum sensor.

[0116] The water level monitoring device is a water level sensor.

[0117] The water injection control device is a water injection valve connected to the exhaust pipe of the feedwater pump turbine; the valve operation module includes an electric actuator and a manual operating mechanism.

[0118] The working principle of the present invention is:

[0119] Load monitoring and adjustment: Real-time monitoring and adjustment of unit load ensures that the unit load has been safely reduced to below 50% BMCR before shutting down the faulty feedwater pump turbine.

[0120] Fault diagnosis and advance preparation: Diagnose the faulty feedwater pump turbine, confirm the type and severity of the fault, and perform necessary advance preparations, including checking spare equipment, notifying maintenance personnel, and preparing safety measures.

[0121] Shutdown operation: Perform shutdown operation, close the steam valve, cut off the steam supply, and gradually reduce the feed water pump load until it stops running completely.

[0122] System isolation: After shutdown, the feedwater pump turbine is isolated and all related pipes and valves are closed to prevent the medium from continuing to flow.

[0123] Vacuum regulation: By opening the condenser vacuum pressure regulating door, the vacuum degree can be accurately controlled to -90kPa to create conditions for subsequent operations.

[0124] Water level monitoring and water injection: Open the manual water injection door, monitor the water level changes in real time through the water level monitoring equipment, and adjust the manual door opening to maintain a stable water level.

[0125] Cylinder opening inspection: After confirming that the exhaust butterfly valve is tightly closed, the main engine vacuum is stable, and the exhaust pressure has dropped to zero, the cylinder opening inspection is carried out.

[0126] Automation module: Utilize the speed monitoring module, vacuum monitoring module, water level monitoring module, water injection control module and valve operation module to realize automatic control of the entire isolation process.

[0127] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for isolating a feedwater pump turbine, characterized in that: The following steps are involved: a. When the unit is reduced to 50% BMCR load, shut down the faulty feedwater pump turbine; b. Check that the steam inlet electric door and regulating valve of the water supply pump are closed tightly; c. After the speed of the feedwater pump steam turbine drops to 0, close the feedwater pump steam turbine exhaust butterfly valve; d. Check that the exhaust butterfly valve is fully closed, close the drain electric door in front of the exhaust butterfly valve, and cut off the power to the electric door; e. Open the condenser vacuum pressure regulating valve to reduce the unit condenser vacuum to -90kPa; f. Unlock the joint behind the primary door of the feedwater pump turbine vacuum pressure transmitter, connect the hose to the condensate pit, and monitor the water level of the feedwater pump discharge cylinder; g. Insert the exhaust pipe spring bracket stop pin into the exhaust pipe and lock it to form a rigid support to prevent the turbine exhaust pipe from being overloaded and deformed during water injection; h. Open the electric door for cooling water from the exhaust pipe of condensate to the feedwater pump turbine to inject water into the feedwater pump turbine; i. Open the exhaust pipe of the feedwater pump turbine, lead out the stainless steel pipe to the exhaust pipe of the feedwater pump turbine, and add a manual door; j. Open the manual valve for filling the water supply from the feedwater pump to the exhaust pipe of the feedwater pump, adjust the opening of the manual valve, and control the water level; k. Test-stop the feedwater pump turbine shaft seal and check the condenser vacuum drop; l. After the vacuum is stable, close the manual steam inlet and return doors of the feedwater pump turbine shaft seal; m. After judging that the exhaust butterfly valve is tightly closed, the main engine vacuum is maintained stable, and the exhaust pressure reaches zero, open the cylinder for inspection.

2. The method for isolating a feedwater pump turbine according to claim 1, characterized in that: In the step a, specifically: a1. Load monitoring and adjustment: Before shutting down the feedwater pump turbine, first monitor the load of the entire power plant unit in real time to ensure that the current load has been reduced to below 50% BMCR; a2. Fault diagnosis: Conduct detailed fault diagnosis on the feedwater pump turbine to confirm whether there is a fault, as well as the type and severity of the fault; a3. Advance preparation: After confirming that the faulty feedwater pump steam turbine needs to be shut down, the operator needs to carry out advance preparation work, including but not limited to checking the status of the standby feedwater pump steam turbine to ensure that it can be started at any time to take over the work of the faulty unit; Notify relevant maintenance personnel and engineers to prepare maintenance tools and equipment; and prepare necessary safety measures and emergency plans; a4. Shutdown operation: The operator will perform the shutdown operation, close the steam valve entering the feedwater pump turbine, cut off the steam supply, and reduce the load of the feedwater pump until it stops running completely; a5. System isolation: After the feedwater pump turbine is shut down, the system is isolated, including closing all pipes and valves connected to the feedwater pump turbine to ensure that no medium continues to flow into or out of the feedwater pump turbine, so as to facilitate subsequent maintenance work; a6. Safety inspection: After the shutdown and isolation operations are completed, conduct a safety inspection of the feedwater pump turbine and its surrounding areas to ensure that there are no leaks, overheating or other potential safety hazards; a7. Records and reports: The operator needs to keep detailed records of the shutdown operation process and report to the superior management in order to arrange subsequent maintenance work and adjust the unit operation plan.

3. The method for isolating a feedwater pump turbine according to claim 1 or 2, characterized in that: The step e is specifically as follows: e1. Evaluate the current vacuum degree: Evaluate the current vacuum degree of the condenser, check the real-time vacuum reading of the condenser through the monitoring system, and ensure that it is within the normal operating range; e2. Prepare the regulating equipment: ensure that the driving mechanism of the condenser vacuum pressure regulating door is in good condition; check the limit switch and position indicator of the regulating door to ensure that they accurately reflect the state of the regulating door; e3. Open the regulating door: Open the condenser vacuum pressure regulating door to avoid the impact of rapid pressure changes on the unit; the regulating door is opened in stages, and the change of vacuum degree must be checked after each adjustment; c4. Monitor vacuum changes: During the adjustment process, continuously monitor the vacuum gauge of the condenser to ensure that the vacuum changes meet expectations; e5. Reach the target vacuum: Continue to fine-tune the regulating door until the vacuum of the condenser drops to -90kPa; once the target vacuum is reached, stabilize the door opening to ensure that the vacuum remains at the set value; e6. Record the operation process: record the data during the operation, including the final opening of the regulating door, the change process of the condenser vacuum degree and the operation time; e7. Notify subsequent operators: When the condenser vacuum stabilizes at -90kPa, notify subsequent operators to isolate and repair the feedwater pump turbine.

4. The method for isolating a feedwater pump turbine according to claim 3, characterized in that: The step j is specifically as follows: j1. Open the manual water injection door: Open the manual water injection door for the feedwater pump to inlet the sealing water to the exhaust pipe of the feedwater pump, and start injecting water into the exhaust pipe; j2. Monitor water level changes: Use water level monitoring equipment to monitor water level changes in the exhaust pipe of the feedwater pump in real time; j3. Adjust the opening of the manual door: adjust the opening of the manual door according to the water level monitoring results; j4. Maintain a stable water level: adjust the opening of the manual door to keep the water level below the height of the feedwater pump turbine blades; j5. Record operation data: record the start and end time of water injection, the opening degree of the manual door, and the change of water level.

5. The method for isolating a feedwater pump turbine according to claim 4, characterized in that: The step m is specifically as follows: m1 Measure the vacuum of the main engine: Use a vacuum monitoring instrument to monitor the vacuum status of the main engine in real time to ensure that there is no abnormal change in the vacuum degree of the main engine after the exhaust butterfly valve is closed; m2. Check exhaust steam pressure: Check the pressure of the exhaust steam pipe through the pressure monitoring instrument to confirm that it has dropped to zero or close to zero pressure level; m3. Stable vacuum degree: After the exhaust pressure drops to zero, continue to monitor the vacuum degree to ensure that it remains stable without fluctuation or decline; m4. Cylinder opening operation: After confirming that all safety measures are in place, start the cylinder opening operation.

6. A feedwater pump turbine isolation system for implementing the method according to any one of claims 1 to 5, characterized in that: include: Speed ​​monitoring module, used to monitor the real-time speed of the feedwater pump turbine; Vacuum monitoring module, used to monitor the vacuum degree of the unit condenser; Water level monitoring module, used to monitor the water level of the discharge cylinder of the feedwater pump; A water injection control module, used to control the water injection operation of the feedwater pump turbine; The valve operation module is used to perform the opening and closing operations of the feedwater pump turbine exhaust butterfly valve and valve components.

7. The feedwater pump turbine isolation system according to claim 6, characterized in that: The speed monitoring module speed sensor.

8. The feedwater pump turbine isolation system according to claim 6, characterized in that: The vacuum monitoring module is a vacuum sensor.

9. The feedwater pump turbine isolation system according to claim 6, characterized in that: The water level monitoring device is a water level sensor.

10. The feedwater pump turbine isolation system according to claim 3, characterized in that: The water injection control device is a water injection valve connected to the exhaust pipe of the feedwater pump turbine; the valve operation module includes an electric actuator and a manual operating mechanism.

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