Floating access door for draining and overhauling sluice chamber of hydropower station sluice and using method of floating access door for draining and overhauling sluice chamber of hydropower station sluice

Abstract

The floating access door comprises a floating door body, a sealing structure arranged at the bottom end of the floating door body, a pump cabin arranged at the bottom of the floating door body and ballast tanks arranged around the pump cabin, the ballast tanks are arranged in mirror symmetry along the middle of the floating door body, and the pump cabin is connected with the ballast tanks. Side face sealing structures are arranged on the two sides of the floating door body. The effects that the posture stability, the operation automation degree, the sealing effect, the drainage efficiency, the safety, the maintenance efficiency and the operation convenience of the floating door are improved are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of floating inspection doors, and in particular to a floating inspection door used for draining and inspecting a sluice chamber of a hydropower station and a use method thereof. Background Art

[0002] During the regular maintenance of the sluice gate chamber of a hydropower station, a floating inspection door (referred to as: floating door) is a commonly used device. The main function of the floating door is to isolate the lock chamber from the outside world during the maintenance period. By aligning the floating door with the gate hole and making the floating door fit tightly with the gate hole to form a seal, the water in the lock chamber is drained to facilitate the maintenance of the lock chamber. However, there are some problems with the existing floating door during use, especially when the floating door sinks or floats, it is easy to deviate or tilt, which affects the construction efficiency and safety.

[0003] Specifically, they are as follows: 1. During the sinking or floating process of the floating door, it is necessary to ensure that the center of gravity of the floating door is at the center of the floating door structure, that is, the floating door as a whole remains horizontal to avoid tilting or shifting of the floating door posture. Although the cabins inside the floating door are arranged symmetrically, the consistency of the corresponding cabins during the water inlet and outlet process cannot be guaranteed, resulting in unstable floating door posture.

[0004] 2. It is usually necessary to manually monitor the water level in the cabin and contact personnel in real time to control the valve, which leads to high labor intensity for the staff and poses a safety hazard.

[0005] 3. The sealing effect between the float valve and the gate hole is greatly affected by the posture of the float valve. If the posture of the float valve is unstable, the sealing effect will deteriorate, causing water leakage and affecting maintenance work.

[0006] 4. The drainage process of the lock chamber is divided into the first and second phases. The first phase uses the main pump for preliminary drainage, and the second phase uses the submersible pump for fine drainage. Due to the unstable attitude of the floating gate, the drainage efficiency may be reduced and the maintenance time may be extended. Summary of the invention

[0007] The technical problem to be solved by the present invention is that the floating door is prone to deviation or tilt during its descent, which poses a potential safety hazard.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: a floating inspection door for draining and repairing the sluice chamber of a hydropower station, comprising a floating valve body, a sealing structure arranged at the bottom of the floating valve body, a pump cabin at the bottom of the floating valve body, and a ballast tank arranged around the pump cabin, the ballast tanks are arranged in a mirror-symmetrical manner along the middle of the floating valve body, the pump cabin is connected to the ballast tanks, and side sealing structures are arranged on both sides of the floating valve body.

[0009] Preferably, the floating door body includes a base and a control platform located in the middle of the top of the base, the ballast tank is located in the base, the base is an octagonal structure, the control platform is a rectangular structure, and the outer side of the control platform is connected to the base through a ladder.

[0010] Preferably, a connecting pipeline is provided in the base, the connecting pipeline connects the front side wall and the rear side wall of the base, and the pump cabin is located on the connecting pipeline.

[0011] Preferably, two main pumps are provided in the pump room, and the two main pumps are arranged in parallel on the drainage pipeline, the output end of the drainage pipeline is connected to the bottom of the float body, and the output end is connected to the ballast tank. A water inlet pipeline is also provided in the pump room, and the water inlet pipeline is connected to the ballast tank.

[0012] Preferably, the ballast tanks include a first ballast tank, a second ballast tank and a third ballast tank, the first ballast tank is distributed at the front and rear sides of the pump cabin, the second ballast tank is distributed at the four corners of the pump cabin, and the third ballast tank is distributed at the left and right sides of the pump cabin.

[0013] Preferably, the sealing structure comprises a first sealing structure disposed at the front edge of the floating valve body and a second sealing structure arranged in the middle of the floating valve body.

[0014] The method for using the floating inspection door for draining and inspecting the sluice chamber of a hydropower station comprises the following steps: S1. Floating gate towing: Use a push tugboat to tow the floating gate body to the lock chamber maintenance area; S2, the floating gate is shifted, and the floating gate body is moved to the front of the gate hole aligned with the gate chamber of the sluice gate; S3, the floating gate sinks, controls the water inflow into the ballast tank in the floating gate body, makes the floating gate body sink, fits tightly with the gate hole bottom plate and gate pier, sits on the bottom stably, and forms a seal with the gate hole by relying on the sealing structure on both sides and bottom of the floating gate body; S4, the first phase of the lock chamber is partially drained. The valves upstream and downstream of the floating gate body are opened, and the two main pumps in the pump room are started to pump out the lock chamber. When the water depth in the lock chamber is less than 110cm, the main pump of the floating gate is closed, and a submersible pump is arranged in the lock chamber near the floating gate upstream of the floating gate. The submersible pump is started to continue draining water; S5. Leakage plugging in the drainage area: During the drainage process, the water-stopping parts of the floating valve body and the leakage parts of the inspection door upstream of the lock chamber are plugged to reduce the infiltration water upstream and downstream of the lock chamber; S6. The lock chamber is drained in the second phase, and the main pump and submersible pump are used for partial drainage in the first phase until the water depth in the lock chamber is below 20 cm. The submersible pump is then turned off, and the maintenance personnel enter the lock chamber. A small temporary water retaining cofferdam with a height of not less than 50 cm and parallel to the floating gate and the inspection gate is set up in two areas upstream of the floating gate and near the floating gate, and downstream of the inspection gate and near the inspection gate, respectively, to form two closed water storage areas. At the same time, a submersible pump is arranged in the water storage area near the inspection gate to pump the water flow in the water storage area near the inspection gate to the water storage area near the floating gate, and micro submersible pumps are arranged on the periphery of the two water storage areas to pump the residual water in the lock chamber with a depth of less than 20 cm to the water storage area, forming dry land maintenance conditions in the lock chamber except for the two water storage areas; S7, filling and leveling. After the lock chamber is overhauled, the lock chamber is leveled and leveled. The connecting pipe in the floating valve body is opened, and the river water downstream of the floating valve body enters the lock chamber. S8, the floating valve floats up, and when the water levels upstream and downstream of the floating valve body reach the same level, all valves on the floating valve body are closed, and the floating valve body is controlled to discharge the water in the ballast tank, and the floating valve body floats up, and finally a pusher is used to move the floating valve body out.

[0015] Preferably, in the step S1, the accumulated water in the ballast tank of the floating valve body is drained, and then the floating valve body is moved.

[0016] Preferably, in step S3, the two ballast tanks at the left and right ends of the floating valve body are first controlled to be filled with water. After the two ballast tanks are full of water, the two ballast tanks at the front and rear sides of the floating valve body are controlled to be filled with water. Finally, the four ballast tanks at the angle of the floating valve body are controlled to be filled with water.

[0017] Preferably, in step S7, after the internal and external water filling and pressure equalization of the lock chamber is completed, the outer side pipelines of the lock chamber and the relatively grouped ballast tanks are connected in sequence to equalize the pressure of the ballast tanks. After the equalization is completed, the lock chamber is drained in sequence in the reverse order of water inflow into the lock chamber.

[0018] The present invention provides a floating inspection door for draining and repairing the sluice chamber of a hydropower station and a method for using the same. Through a number of innovative designs and technical means, the attitude stability, degree of operation automation, sealing effect, drainage efficiency, safety, inspection efficiency and operation convenience of the floating door are significantly improved, while the reliability of the system is improved. The specific beneficial effects are as follows: 1. The ballast tanks are arranged in a mirror-symmetrical manner along the middle of the floating door body to ensure that the center of gravity of the floating door always remains at the center of the structure during the water inlet and outlet process, avoiding tilting or offset of the floating door posture. The phased water inlet method (first control the water inlet of the ballast tanks at the left and right ends, then control the water inlet of the ballast tanks on the front and rear sides, and finally control the water inlet of the ballast tanks at the angle) further ensures that the floating door always remains horizontal and improves the stability of the floating door posture. Two main pumps and water inlet pipelines are installed in the pump room. The water inlet and outlet of the ballast tanks are monitored and controlled by the automatic control system, reducing human intervention and reducing the labor intensity of the staff. The real-time monitoring system monitors the water level of each compartment of the floating door in real time through sensors and control systems to ensure the consistency and accuracy of the water inlet and outlet process and improve the degree of automation of operation.

[0019] 2. Multi-layer sealing structures are set on both sides and the bottom of the floating gate body, including the first sealing structure on the front edge and the second sealing structure in the middle, to ensure that the floating gate and the gate hole form a tight seal to prevent water leakage. Multiple sealing measures are set at each water-stopping part of the floating gate body to ensure the sealing effect between the floating gate and the gate hole during the drainage process, reduce the infiltration water upstream and downstream of the lock chamber, and improve the sealing effect. The lock chamber drainage is divided into the first and second phases. The first phase uses the main pump and submersible pump for partial drainage, and the second phase uses a small temporary water retaining cofferdam and a micro submersible pump for fine drainage to ensure that the water depth in the lock chamber drops below 20cm, forming dry land maintenance conditions. The two main pumps in the pump room are arranged in parallel to improve drainage efficiency, shorten drainage time, and improve the efficiency of maintenance operations, thereby improving drainage efficiency.

[0020] 3. Monitor and control the inflow and outflow of ballast tanks through automatic control systems to reduce human intervention and personal safety risks during operation. Staged inflow and outflow ensure that the floating gate is always in a safe and controllable state, avoiding safety accidents caused by unstable posture and improving safety. Use a push tugboat to quickly tow the floating gate body to the maintenance area of ​​the lock chamber, shorten the transportation time and improve maintenance efficiency. Through staged drainage and efficient drainage system, the water in the lock chamber can be quickly drained, creating good working conditions for maintenance operations, shortening maintenance time and improving maintenance efficiency.

[0021] 4. A control platform is set on the top of the floating valve body to facilitate the operator to operate and monitor, and improve the convenience of operation. The outside of the control platform is connected to the base through a ladder, which is convenient for operators to get on and off the floating valve body to perform necessary operations and maintenance, and improve the convenience of operation. Two main pumps are arranged in parallel in the pump room to ensure that when one pump fails, the other pump can still work normally, thereby improving the reliability of the system. The water level and status of each compartment of the floating valve are monitored in real time through sensors and control systems to ensure the normal operation of the system, prevent unexpected situations caused by failures, and improve the reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 It is the front view of the present invention.

[0023] Figure 2 It is a top view of the present invention.

[0024] Figure 3 It is a side view of the present invention.

[0025] Figure 4 It is a structural schematic diagram of the bottom cabin of the present invention.

[0026] In the figure: 1. floating valve body; 2. first sealing structure; 3. second sealing structure; 4. pump room; 5. first ballast tank; 6. second ballast tank; 7. third ballast tank. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be described more clearly below in conjunction with the accompanying drawings and embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0028] Embodiment 1: like Figure 1-4 As shown, the present invention provides a floating inspection door for draining and repairing a sluice chamber of a hydropower station, comprising a floating valve body 1, a sealing structure arranged at the bottom end of the floating valve body 1, a pump cabin 4 arranged at the bottom of the floating valve body 1, and a ballast tank arranged around the pump cabin 4, the ballast tanks are arranged in a mirror-symmetrical manner along the middle of the floating valve body 1, the pump cabin 4 is connected to the ballast tanks, and side sealing structures are arranged on both sides of the floating valve body 1.

[0029] The side sealing structure is made of MC nylon material, which is processed into a strip structure and fixedly installed on both sides of the floating valve body 1. It has high strength and corrosion resistance. Compared with the hard miscellaneous wood originally used, it reduces the material and processing costs. Water level monitoring sensors are installed in each compartment inside the floating valve body 1, and the water level monitoring sensor signals are connected to the control system.

[0030] like Figure 2 and Figure 4 The floating door body 1 includes a base and a control platform located in the middle of the top of the base, the ballast tank is located inside the base, the base is an octagonal structure, the control platform is a rectangular structure, and the outside of the control platform is connected to the base through a ladder.

[0031] The operating platform includes a balance detection unit arranged on the floating valve body 1. The balance detection unit is distributed at the two ends and the edges of the two sides of the floating valve body 1, and is used to detect whether the floating valve body 1 is balanced as a whole. After detecting that the floating valve body 1 is tilted, the corresponding ballast tank is controlled to flow in with water, so that the upturned end is lowered to level the floating valve body 1.

[0032] like Figure 4 As shown. A connecting pipeline is arranged in the base, and the connecting pipeline connects the front side wall and the rear side wall of the base, and the pump cabin 4 is located on the connecting pipeline. After the floating valve body 1 seals the lock chamber, the connecting pipeline is used to connect the lock chamber with the outside through the connecting pipeline when the lock chamber is drained or filled with water, and assist the lock chamber main pump to drain or fill the lock chamber, and will not affect the sealing of the floating valve body 1. like Figure 4 As shown. Two main pumps are arranged in parallel on the drainage pipeline in the pump room 4. The output end of the drainage pipeline is connected to the bottom of the floating valve body 1, and the output end is connected to the ballast tank. A water inlet pipeline is also arranged in the pump room 4, and the water inlet pipeline is connected to the ballast tank. One of the two main pumps is on and the other is on standby. The main pump draws water from the side of the floating valve body 1, and the water flows by itself and is introduced into the ballast tank.

[0033] like Figure 4 As shown. The ballast tanks include a first ballast tank 5, a second ballast tank 6 and a third ballast tank 7. The first ballast tank 5 is distributed at the front and rear sides of the pump room 4, the second ballast tank 6 is distributed at the four corners of the pump room 4, and the third ballast tank 7 is distributed at the left and right sides of the pump room 4. When the floating valve body 1 is sinking, the ballast tanks at the left and right ends are controlled to be filled with water, that is, the two third ballast tanks 7 are filled with water synchronously, so that the floating valve body 1 sinks. After the two third ballast tanks 7 are completely filled with water, the water inlet pipe of the third ballast tank 7 is closed, and the four second ballast tanks 6 are controlled to be filled with water. Finally, the first ballast tank 5 is filled with water to achieve the sinking of the floating valve body 1.

[0034] like Figure 3 The sealing structure comprises a first sealing structure 2 arranged at the front edge of the floating valve body 1 and a second sealing structure 3 arranged in the middle of the floating valve body 1. The first sealing structure 2 and the second sealing structure 3 perform double-layer sealing to improve the sealing performance between the floating valve body 1 and the bottom of the gate chamber.

[0035] The method for using the floating inspection door for draining and inspecting the sluice chamber of a hydropower station is characterized by comprising the following steps: S1, floating gate towing, using a push tugboat to tow the floating gate body 1 to the lock chamber maintenance area; S2, the floating valve is shifted, and the floating valve body 1 is moved to the front of the gate hole aligned with the gate chamber of the sluice gate; S3, the floating gate sinks, controls the water inflow into the ballast tank in the floating gate body 1, makes the floating gate body 1 sink, fits tightly with the bottom plate of the gate hole and the gate pier, sits on the bottom stably, and forms a seal with the gate hole by relying on the sealing structure on both sides and the bottom of the floating gate body 1; S4, the first phase of partial drainage of the lock chamber, open the valves upstream and downstream of the floating gate body 1, start the two main pumps in the pump room to pump out the lock chamber, when the water depth in the lock chamber is less than 110cm, close the floating gate main pump, arrange a submersible pump in the lock chamber near the floating gate upstream of the floating gate, start the submersible pump to continue drainage; S5. Leakage plugging in the drainage area: During the drainage process, the water-stopping parts of the floating valve body 1 and the leakage parts of the inspection door upstream of the lock chamber are plugged to reduce the infiltration water upstream and downstream of the lock chamber; S6. The lock chamber is drained in the second phase, and the main pump and submersible pump are used for partial drainage in the first phase until the water depth in the lock chamber is below 20 cm. The submersible pump is then turned off, and the maintenance personnel enter the lock chamber. A small temporary water retaining cofferdam with a height of not less than 50 cm and parallel to the floating gate and the inspection gate is set up in two areas upstream of the floating gate and near the floating gate, and downstream of the inspection gate and near the inspection gate, respectively, to form two closed water storage areas. At the same time, a submersible pump is arranged in the water storage area near the inspection gate to pump the water flow in the water storage area near the inspection gate to the water storage area near the floating gate, and micro submersible pumps are arranged on the periphery of the two water storage areas to pump the residual water in the lock chamber with a depth of less than 20 cm to the water storage area, forming dry land maintenance conditions in the lock chamber except for the two water storage areas; S7, filling and leveling. After the lock chamber is overhauled, the lock chamber is leveled and leveled. The connecting pipe in the floating valve body 1 is opened, and the river water downstream of the floating valve body 1 enters the lock chamber. S8, the floating valve floats up, and when the water levels upstream and downstream of the floating valve body 1 reach the same level, all valves on the floating valve body 1 are closed, and the floating valve body is controlled to discharge the water in the ballast tank, and the floating valve body 1 floats up, and finally a pusher is used to move the floating valve body 1 out.

[0036] Submersible pumps are required to be deployed upstream and downstream of the lock chamber to assist in pumping out water and water accumulation in the lock chamber cofferdam. The number of submersible pumps to be started is determined by the amount of water leakage. During the pumping operation, the floating gate operator needs to check the operation of the submersible pump at any time. If the cable insulation is damaged or the operation is abnormal, the cable or pump body must be replaced.

[0037] When the water depth in the lock chamber drops to 1.1m, the ballast tank valve is closed, the main pump of the lock chamber stops running, and the submersible pump continues to pump out water. When the water depth in the lock chamber drops below 40cm, the floating gate operation staff on duty cleans up the floating objects in the lock chamber to prevent the floating objects from blocking the water inlet of the water pump. When the water depth in the lock chamber drops below 30cm, the cofferdam in the lock chamber is erected.

[0038] In the step S1, the accumulated water in the ballast tank of the floating valve body 1 is drained, and then the floating valve body 1 is moved.

[0039] In step S3, the two ballast tanks at the left and right ends of the floating valve body 1 are first controlled to be filled with water. After the two ballast tanks are full of water, the two ballast tanks diagonally opposite to the floating valve body 1 are controlled to be filled with water. Finally, the two ballast tanks at the front and rear ends of the floating valve body 1 are controlled to be filled with water.

[0040] In step S5, after the internal and external water filling and pressure of the lock chamber are completed, the outer pipeline of the lock chamber and the relatively grouped ballast tanks are connected in sequence to perform pressure equalization of the ballast tanks. After the pressure equalization is completed, the lock chamber is drained in sequence in the reverse order of water inflow into the lock chamber.

Claims

1. A floating inspection door used for draining and repairing the sluice chamber of a hydropower station, characterized by: The invention comprises a floating valve body (1), a sealing structure arranged at the bottom end of the floating valve body (1), a pump cabin (4) arranged at the bottom of the floating valve body (1), and a ballast tank arranged around the pump cabin (4), the ballast tank being arranged in mirror symmetry along the middle of the floating valve body (1), the pump cabin (4) being connected to the ballast tank, and side sealing structures being arranged on both sides of the floating valve body (1).

2. The floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 1, characterized in that: The floating door body comprises a base and a control platform located in the middle of the top of the base. The ballast tank is located inside the base. The base is in an octagonal structure, and the control platform is in a rectangular structure. The outer side of the control platform is connected to the base through a ladder.

3. The floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 2, characterized in that: A connecting pipeline is arranged in the base, the connecting pipeline connects the front side wall and the rear side wall of the base, and the pump cabin (4) is located on the connecting pipeline.

4. The floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 3, characterized in that: Two main pumps are arranged in the pump room (4), and the two main pumps are arranged in parallel on a drainage pipeline. The output end of the drainage pipeline is connected to the bottom of the floating valve body (1), and the output end is connected to the ballast tank. A water inlet pipeline is also arranged in the pump room (4), and the water inlet pipeline is connected to the ballast tank.

5. The floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 1, characterized in that: The ballast tanks include a first ballast tank (5), a second ballast tank (6) and a third ballast tank (7); the first ballast tank (5) is distributed at the front and rear sides of the pump cabin (4); the second ballast tank (6) is distributed at the four corners of the pump cabin (4); and the third ballast tank (7) is distributed at the left and right sides of the pump cabin (4).

6. The floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 1, characterized in that: The sealing structure comprises a first sealing structure (2) arranged at the front edge of the floating valve body (1) and a second sealing structure (3) arranged in the middle of the floating valve body (1).

7. The method for using the floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 1, characterized in that: The steps include: S1. Towing of the floating gate: using a push tugboat to tow the floating gate body (1) to the lock chamber maintenance area; S2, the floating valve is shifted, and the floating valve body (1) is moved to the front of the gate hole aligned with the gate chamber of the sluice gate; S3, the floating gate sinks, and the ballast tank in the floating gate body (1) is controlled to enter with water, so that the floating gate body (1) sinks, fits tightly with the bottom plate of the gate hole and the gate pier, sits on the bottom stably, and forms a seal with the gate hole by relying on the sealing structure on both sides and the bottom of the floating gate body (1); S4: Drain the first phase of the lock chamber. Open the valves upstream and downstream of the floating gate body (1), start the two main pumps in the pump room to pump out the lock chamber. When the water depth in the lock chamber is less than 110 cm, turn off the main pump of the floating gate, arrange a submersible pump in the lock chamber near the floating gate upstream of the floating gate, and start the submersible pump to continue draining water. S5. Leakage plugging in the drainage area: During the drainage process, the water-stopping parts of the floating valve body (1) and the leakage parts of the inspection door upstream of the lock chamber are plugged to reduce the infiltration water upstream and downstream of the lock chamber; S6. The lock chamber is drained in the second phase, and the main pump and submersible pump are used for partial drainage in the first phase until the water depth in the lock chamber is below 20 cm. The submersible pump is turned off, and the maintenance personnel enter the lock chamber. A small temporary water retaining cofferdam with a height of not less than 50 cm and parallel to the floating gate and the inspection gate is set up in two areas upstream of the floating gate and near the floating gate, and downstream of the inspection gate and near the inspection gate, respectively, to form two closed water storage areas. At the same time, a submersible pump is arranged in the water storage area near the inspection gate to pump the water flow in the water storage area near the inspection gate to the water storage area near the floating gate, and micro submersible pumps are arranged on the periphery of the two water storage areas to pump the residual water in the lock chamber with a depth of less than 20 cm to the water storage area, forming dry land maintenance conditions in the lock chamber except for the two water storage areas; S7, filling the lock chamber with water and pressurizing it. After the lock chamber is repaired, the lock chamber is filled with water and pressurized. The connecting pipe in the floating valve body (1) is opened, and the river water downstream of the floating valve body (1) enters the lock chamber. S8, the floating valve floats up. When the water levels upstream and downstream of the floating valve body (1) reach the same level, all valves on the floating valve body (1) are closed, and the floating valve body is controlled to discharge the water in the ballast tank. The floating valve body (1) floats up, and finally a pusher is used to move the floating valve body (1) out.

8. The method for using the floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 7, characterized in that: In the step S1, the accumulated water in the ballast tank of the floating valve body (1) is drained, and then the floating valve body (1) is moved.

9. The method for using the floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 7, characterized in that: In step S3, the two ballast tanks at the left and right ends of the floating valve body (1) are first controlled to be filled with water. After the two ballast tanks are full of water, the four ballast tanks at the four corners of the floating valve body (1) are controlled to be filled with water. Finally, the two ballast tanks at the front and rear sides of the floating valve body (1) are controlled to be filled with water.

10. The method for using the floating inspection door for draining and repairing the sluice chamber of a hydropower station as claimed in claim 7, characterized in that: In step S7, after the internal and external water level of the lock chamber is filled and pressurized, the outer pipeline of the lock chamber and the relatively grouped ballast tanks are connected in sequence to pressurize the ballast tanks. After the pressurization is completed, the lock chamber is drained in sequence in the reverse order of water inflow into the lock chamber.

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