Applicable to coal mine underground water pump water-free bottom valve cavitation elimination device and system

Abstract

The present invention discloses a cavitation elimination device and system for underground water pumps in coal mines, which does not require water filling and does not require a bottom valve. The device comprises a negative pressure water storage tank and a negative pressure water inlet pipe. The negative pressure water storage tank may optionally be provided with a water inlet at the top or bottom. The first end of the negative pressure water inlet pipe extends below the liquid level of the lower water tank, and the second end of the negative pressure water inlet pipe is connected to the water inlet. A water outlet is provided on one side of the lower end of the negative pressure water storage tank, and a liquid replenishment pipe and an exhaust pipe are provided on the top of the negative pressure water storage tank. The present invention places the water suction level of the water pump in advance, and the liquid level in the device is always higher than the water pump plane, thereby increasing the cavitation margin of the water pump device and reducing or eliminating the harm of cavitation to the water pump. Before the water pump is started, the cavity is always filled with liquid, and there is no need to fill it with water. The vacuum pump and jet pump can be omitted, and the control process is optimized. At the same time, the device eliminates the bottom valve, eliminating the safety hazards of the bottom valve being damaged and unable to fill it with water and the bottom valve maintenance process, thereby achieving the purpose of rapid start-up and safe operation of the water pump.

Description

Technical Field

[0001] The present invention relates to the technical field of water pump cavitation and fluid mechanics, and in particular to a cavitation elimination device and system for a water pump in a coal mine without filling and without a bottom valve. Background Art

[0002] Coal mine safety relies on four key elements, commonly known as the "four pillars": hoisting, ventilation, drainage, and compressed air. This demonstrates the crucial importance of drainage systems to coal mine safety. Coal mine drainage equipment is a centrifugal water pump, typically located above a silo. Before starting, water must be pumped into the water pipes and pump chamber to ensure full operation. Otherwise, the pump will be unable to draw water, resulting in a "dry burn" condition, seriously impacting its service life. Each pump requires priming, a task typically performed by a jet pump or a vacuum pump. While these pumps operate on different principles, they all achieve a certain vacuum in the working chamber, drawing water into the pump's working chamber and suction pipe to ensure proper startup. To prevent water from backflowing into the suction pipe when the pump stops, a foot valve is typically installed at the bottom of the suction pipe. This valve improves the efficiency of the vacuum pump and jet pump, shortens priming time, and allows for manual priming in the event of a malfunction. Therefore, vacuum pumps and jet pumps are crucial devices for assisting with pump startup. However, this control method also presents the following challenges:

[0003] 1) Due to problems such as packing leakage, seal aging, and loose sealing in the water pump, the vacuum pump and jet pump cannot form a vacuum in the pump chamber, so that the water pump cannot be filled with water or the water filling time is too long, making the water pump unable to work normally.

[0004] 2) Since the water pump is usually placed several meters above the water surface, the cavitation margin of the water pump is small, resulting in the water inlet pressure being lower than the water outlet pressure when the water pump is running. Cavitation will occur in the water pump cavity. The impact pressure generated by the cavitation phenomenon can easily cause the impeller surface to peel off, destroying the dynamic balance of the impeller. When the impeller is running, it will generate vibration and noise, reducing the working efficiency and service life of the water pump and affecting the safe operation of the water pump. Summary of the Invention

[0005] In order to solve the technical problems in the background technology, the present invention provides a cavitation elimination device and system for a coal mine underground water pump without water filling and without a bottom valve.

[0006] One purpose of the present invention is to provide a cavitation elimination device for a coal mine underground water pump without filling and without a bottom valve, which adopts the following technical scheme: it includes a negative pressure water storage tank and a negative pressure water inlet pipe, the negative pressure water storage tank can optionally be provided with a water inlet at the top or bottom, the first end of the negative pressure water inlet pipe extends below the liquid level of the lower water tank, the second end of the negative pressure water inlet pipe is connected with the water inlet, when the water inlet is provided at the bottom of the negative pressure water storage tank, the second end of the negative pressure water inlet pipe extends from the bottom of the tank to the top of the tank; a water outlet is provided on one side of the lower end of the negative pressure water storage tank, and the water outlet is connected with the water inlet of the water pump through the outlet pipe; a liquid replenishing pipe and an exhaust pipe are provided at the top of the negative pressure water storage tank, the liquid replenishing pipe is connected with the water replenishing mechanism, and is used to replenish water into the negative pressure water storage tank, and the exhaust pipe is used to exhaust air outward, and a water level sensor is provided on the negative pressure water storage tank for detecting the water level in the negative pressure water storage tank.

[0007] As an optimization solution, the liquid replenishment pipe includes an automatic water replenishment pipe and a manual water replenishment pipe. The automatic water replenishment pipe is provided with an electric water replenishment valve, and the manual water replenishment pipe is provided with a manual water replenishment valve. The ends of the automatic water replenishment pipe and the manual water replenishment pipe are connected through a first three-way piece and are connected to the water supply pipe of the water replenishment mechanism.

[0008] As an optimized solution, the exhaust pipe includes an automatic exhaust pipe and a manual exhaust pipe. The automatic exhaust pipe is provided with an electric exhaust valve, and the manual exhaust pipe is provided with a manual exhaust valve. The ends of the automatic exhaust pipe and the manual exhaust pipe are connected through a second three-way piece and can exhaust to the outside.

[0009] As an optimization solution, a water level sensor is provided on the negative pressure water storage tank.

[0010] As an optimization solution, a negative pressure sensor is provided on the negative pressure water storage tank.

[0011] As an optimization solution, a flow sensor is provided on the water outlet pipe.

[0012] As an optimization solution, a flow sensor is provided on the negative pressure water storage tank.

[0013] As an optimization solution, the negative pressure water storage tank is provided with a sewage outlet, and the sewage outlet can be optionally provided on the side of the negative pressure water storage tank or at the bottom of the negative pressure water storage tank.

[0014] As an optimization solution, the negative pressure water storage tank is provided with a sewage outlet, and the sewage outlet can be optionally provided on the side or bottom of the negative pressure water storage tank.

[0015] As an optimization solution, a manual drain valve is provided on the bottom plate of the negative pressure water storage tank.

[0016] Another object of the present invention is to provide a cavitation elimination system for underground water pumps in coal mines without filling water and without bottom valves. The system includes the cavitation elimination device for underground water pumps in coal mines without filling water and without bottom valves described in the present invention.

[0017] Compared with the prior art, the advantages of the present invention are:

[0018] The present invention's cavitation-eliminating device for underground coal mine water pumps, which requires no priming and has no bottom valve, pre-positions the pump's suction level. This ensures that the liquid level within the device is always above the pump's surface, improving the pump's NPSH and reducing or eliminating the risk of cavitation to the pump. Before the pump starts, the chamber is always filled with liquid, eliminating the need for priming. This eliminates the need for a vacuum pump and jet pump, optimizing the control process. Furthermore, the device eliminates the need for a bottom valve, eliminating the potential safety hazards of a damaged bottom valve preventing priming and the need for bottom valve maintenance, achieving rapid startup and safe operation of the pump.

[0019] The present invention is applicable to a cavitation elimination system for a water-free bottom valve-less water pump in a coal mine, and can control the operation of the cavitation elimination device for a water-free bottom valve-less water pump in a coal mine in real time, effectively and automatically, thereby realizing precise control of the internal liquid level of a negative pressure water storage tank in each stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a right side view of an embodiment of the present invention applicable to a cavitation elimination device for underground coal mine water pumps without water filling and without a bottom valve;

[0021] Figure 2 This is a left view of an embodiment of the present invention applicable to a cavitation elimination device for underground coal mine water pumps without water filling and without a bottom valve;

[0022] Figure 3 This is a front view of an embodiment of the present invention applicable to a cavitation elimination device for underground coal mine water pumps without water filling and without a bottom valve;

[0023] Figure 4 A top view of an embodiment of the present invention for a cavitation elimination device for a water-free, bottom-valve-less water pump in a coal mine;

[0024] Figure 5 A cross-sectional view of another embodiment of the cavitation elimination device for underground water pumps in coal mines without water filling and without bottom valves;

[0025] Among them, 1-negative pressure water storage tank, 2-negative pressure water inlet pipe, 3-water inlet, 4-water outlet pipe, 5-water pump, 6-liquid supply pipe, 7-exhaust pipe, 8-first three-way fitting, 9-second three-way fitting, 10-water level sensor, 11-negative pressure sensor, 12-flow sensor, 13-sewage outlet, 14-manual drain valve,

[0026] 61-Automatic water supply pipe, 62-Manual water supply pipe, 63-Electric water supply valve, 64-Manual water supply valve,

[0027] 71-Automatic exhaust pipe, 72-Manual exhaust pipe, 73-Electric exhaust valve, 74-Manual exhaust valve. DETAILED DESCRIPTION

[0028] In order to facilitate those skilled in the art to understand the technical solution of the present invention, the following is further described with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention.

[0029] In the following detailed description, for ease of explanation, numerous specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, it is apparent that one or more embodiments may be practiced without these specific details. In addition, in the following description, descriptions of known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention.

[0030] Example 1:

[0031] Please refer to Figure 1-4 , which is a schematic structural diagram from multiple angles of the present invention's bottomless valve-free cavitation elimination device for underground coal mine water pumps. The device includes a negative pressure water tank 1 and a negative pressure water inlet pipe 2. The negative pressure water tank 1 can be a sealed metal tank, and of course, its shape is not limited to a cylindrical structure. In this embodiment, the negative pressure water tank 1 has a water inlet 3 at its top. The first end of the negative pressure water inlet pipe 2 extends below the liquid level in the lower water tank. The second end of the negative pressure water inlet pipe 2 is connected to the water inlet 3, and is used to store water in the negative pressure water tank 1 when negative pressure is formed in the tank. A water outlet is provided on one side of the lower end of the negative pressure water tank 1, and the water outlet is connected to the water inlet of the water pump 5 via an outlet pipe 4. A liquid infusion pipe 6 and an exhaust pipe 7 are provided at the top of the negative pressure water tank 1. The liquid infusion pipe 6 is connected to the water infusion mechanism and is used to add water to the negative pressure water tank 1. The exhaust pipe 7 is used to exhaust air outward. A water level sensor 10 is provided on the negative pressure water storage tank 1 , and the water level sensor 10 is used to detect whether the water level in the negative pressure water storage tank 1 meets the required water level for starting the water pump.

[0032] Normally, both the infusion pipe 6 and the exhaust pipe 7 are closed. During operation, this embodiment requires that the lowest water level in the negative pressure water storage tank 1 always be higher than the highest water level in the outlet pipe 2. Therefore, before the water pump starts, the water level sensor 10 detects the water level in the negative pressure water storage tank 1. If the water level is lower than the pump start-up requirement, both the infusion pipe 6 and the exhaust pipe 7 are opened. The infusion pipe 6 replenishes water into the negative pressure water storage tank 1 cavity through a water supply mechanism, such as a production water supply pipeline, and the gas in the negative pressure water storage tank 1 cavity is discharged through the exhaust pipe 7. When the water level in the negative pressure water storage tank 1 reaches the pump start-up requirement, the infusion pipe 6 and the exhaust pipe 7 are closed, and the water pump can start.

[0033] When the water pump is started, the water level in negative pressure water storage tank 1 drops rapidly, generating negative pressure within the tank. Atmospheric pressure then pushes the water in the lower sump into negative pressure water storage tank 1 through negative pressure water inlet pipe 2, resulting in continuous water pumping. When the water pump stops, the negative pressure in negative pressure water storage tank 1 gradually decreases, causing the water level to rise until the pressure inside and outside the tank equalizes, at which point the water level stops rising.

[0034] In this embodiment, the refill pipe 6 includes an automatic refill pipe 61 and a manual refill pipe 62. The automatic refill pipe 61 is equipped with an electric refill valve 63, while the manual refill pipe 62 is equipped with a manual refill valve 64. The ends of the automatic and manual refill pipes 61 and 62 are connected by a first T-piece 8 and communicate with the water supply pipe of the refill mechanism. This embodiment provides both an automatic refill pipe 61 and a backup manual refill pipe 62, allowing for automatic or manual activation based on actual needs, facilitating on-site construction.

[0035] Similarly, the exhaust pipe 7 includes an automatic exhaust pipe 71 and a manual exhaust pipe 72 as a backup. The automatic exhaust pipe 71 is provided with an electric exhaust valve 73, and the manual exhaust pipe 72 is provided with a manual exhaust valve 74. The ends of the automatic exhaust pipe 71 and the manual exhaust pipe 72 are connected by a second three-way piece 9 and can exhaust to the outside.

[0036] In this embodiment, a negative pressure sensor 11 is provided on the negative pressure water storage tank 1. The negative pressure sensor 11 is used to detect the negative pressure value in the negative pressure water storage tank 1 to prevent the negative pressure water storage tank 1 from being sealed improperly, causing device failure and affecting the normal use of the water pump.

[0037] In this embodiment, a flow sensor 12 is provided on the water outlet pipe 2. The flow sensor 12 is used to detect the flow in the water outlet pipe 2. If the flow is too low, it means that the water level in the negative pressure water storage tank 1 is low, which may easily cause the water pump to "dry burn". The flow sensor 12 detects when the water pump is running and does not detect when the water pump is stopped.

[0038] In this embodiment, the negative pressure water storage tank 1 is provided with a drain port 13, which can be optionally provided on the side or bottom of the negative pressure water storage tank 1. The drain port 13 is used for internal maintenance of the negative pressure water storage tank 1 and for discharging silt or foreign matter inside the negative pressure water storage tank 1.

[0039] In this embodiment, a manual drain valve 13 is further provided. The manual drain valve 13 is used to drain the accumulated water in the negative pressure water storage tank 1 , thereby facilitating internal inspection and relocation of the negative pressure water storage tank 1 .

[0040] In summary, this device has a simple structure and not only improves the reliability of water pump operation, but is also of great significance to coal mine production safety. Because the device is always filled with water and the water level is always higher than the maximum liquid level of the water pump, the chamber is always full of liquid before the water pump starts. There is no need for a vacuum pump or jet pump to evacuate the water pump before starting, nor is there a need for a bottom valve to prevent water backflow. At the same time, because the liquid level in the device is higher than the water pump level, the cavitation margin of the water pump device is improved, effectively overcoming the damage caused by cavitation to the water pump, and extending the service life and working efficiency of the water pump.

[0041] Example 2:

[0042] See also Figure 5 The figure shows a cross-sectional view of another embodiment of the present invention's cavitation elimination device for underground coal mine water pumps without filling and without a bottom valve. This embodiment differs from the first embodiment primarily in that the water inlet 3 of the negative pressure water storage tank 1 is located at the tank bottom. After the negative pressure water inlet pipe 2 is connected to the water inlet 3, the second end of the negative pressure water inlet pipe 2 extends from the tank bottom to the tank top. In this case, the negative pressure generated within the negative pressure water storage tank 1 can still be effectively utilized to pump water from the lower water tank into the tank body, thereby achieving a continuous water pumping effect.

[0043] The present invention also provides a cavitation elimination system for coal mine underground water pumps without water filling and without bottom valves, which includes the above-mentioned embodiment one or embodiment two, to better achieve the purpose of the present invention. The present invention is applicable to the cavitation elimination system for coal mine underground water pumps without water filling and without bottom valves. The device can be program-controlled by a PLC-touch screen automatic control system and a power control module. The PLC-touch screen automatic control system is electrically connected to each control valve and sensor in the device to monitor and control the automatic operation of the device. The entire processing process does not require human intervention and is completely unmanned. It can control the operation of the cavitation elimination device for coal mine underground water pumps without water filling and without bottom valves in real time, and realize precise control of the internal liquid level of the negative pressure water storage tank in each stage, which not only meets the requirements of digital coal mine construction, but also achieves the economic goal of reducing manpower and increasing efficiency.

[0044] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. Applicable to coal mine underground water pump water-free bottom valve cavitation elimination device, characterized by: The invention comprises a negative pressure water storage tank (1) and a negative pressure water inlet pipe (2), wherein a water inlet (3) is provided at the bottom of the negative pressure water storage tank (1), a first end of the negative pressure water inlet pipe (2) extends below the liquid level of the lower water tank, a second end of the negative pressure water inlet pipe (2) is communicated with the water inlet, and the second end of the negative pressure water inlet pipe (2) extends from the bottom of the tank to the top of the tank; a water outlet is provided on one side of the lower end of the negative pressure water storage tank (1), and the water outlet is communicated with the water inlet of a water pump (5) through an outlet pipe (4); a liquid replenishing pipe (6) and an exhaust pipe (7) are provided at the top end of the negative pressure water storage tank (1), the liquid replenishing pipe (6) is communicated with a water replenishing mechanism and is used to replenish water into the negative pressure water storage tank (1), and the exhaust pipe (7) is used to exhaust air outwards; a water level sensor (10) is provided on the negative pressure water storage tank (1) and is used to detect the water level in the negative pressure water storage tank (1); The liquid replenishing pipe (6) comprises an automatic water replenishing pipe (61) and a manual water replenishing pipe (62), wherein the automatic water replenishing pipe (61) is provided with an electric water replenishing valve (63), and the manual water replenishing pipe (62) is provided with a manual water replenishing valve (64), and the ends of the automatic water replenishing pipe (61) and the manual water replenishing pipe (62) are connected through a first three-way piece (8) and are connected to the water supply pipe of the water replenishing mechanism; The exhaust pipe (7) comprises an automatic exhaust pipe (71) and a manual exhaust pipe (72); the automatic exhaust pipe (71) is provided with an electric exhaust valve (73); the manual exhaust pipe (72) is provided with a manual exhaust valve (74); the ends of the automatic exhaust pipe (71) and the manual exhaust pipe (72) are connected through a second three-way piece (9) and can exhaust to the outside.

2. The cavitation elimination device for underground coal mine water pumps without filling and without bottom valve according to claim 1 is characterized in that: The negative pressure water storage tank (1) is provided with a negative pressure sensor (11).

3. The cavitation elimination device for underground coal mine water pumps without filling water and without bottom valve according to claim 2 is characterized in that: A flow sensor (12) is provided on the water outlet pipe (4).

4. The cavitation elimination device for underground coal mine water pumps without filling water and without bottom valve according to claim 3 is characterized in that: The negative pressure water storage tank (1) is provided with a sewage outlet (13), and the sewage outlet (13) can be optionally provided on the side or bottom of the negative pressure water storage tank (1).

5. The cavitation elimination device for underground coal mine water pumps without filling and without bottom valve according to claim 4 is characterized in that: A manual drain valve (14) is provided on the bottom plate of the negative pressure water storage tank (1).

6. Applicable to coal mine underground water pump water-free bottom valve cavitation elimination system, characterized by: The invention comprises the cavitation elimination device for underground water pumps in coal mines without filling water and without bottom valve as described in any one of claims 1 to 5.

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