High-lift double-pipe or multi-pipe water lifting system for strengthening water hammer protection effect

Abstract

The utility model belongs to the technical field of water supply and drainage, and particularly discloses a high-lift double-pipe or multi-pipe water lifting system capable of strengthening the protection effect of a water hammer. The system comprises at least two lifting pumps and two lifting pipes, water inlets of the lifting pumps are communicated with a low-position water source, water outlets of the lifting pumps are communicated with the lifting pipes, communicating pipes which are communicated with one another are arranged between the lifting pipes, groups of check valves are arranged on the lifting pipes at intervals, each group of check valves comprises a check valve arranged on the corresponding lifting pipe, and each group of check valves comprises a check valve arranged on the corresponding lifting pipe. And the upstream of any check valve in one group of check valves cannot be communicated with the downstream of other check valves in the same group of check valves. The lifting pipes are provided with groups of check valves, the water hammer effect action height is divided into a plurality of sections, the maximum pressure of water hammers is effectively reduced, and the communicating pipes enable the water hammers between the lifting pipes to collide with one another to dissipate energy so as to reduce the pressure of the water hammers. And when the bridging water hammer occurs, water in the lower pipe section can open the check valve to enter the upper part under the action of negative pressure so as to reduce harm, so that the water hammer protection effect of the water lifting system is enhanced.

Description

Technical Field

[0001] The utility model belongs to the technical field of water supply and drainage, and particularly relates to a high-lift double-pipe or multi-pipe water-lifting system for enhancing the water hammer protection effect. Background Technique

[0002] The water hammer effect is a pressure fluctuation phenomenon caused by a sharp change in the water flow velocity. The pressure increase caused by the water hammer effect can reach several times or even dozens of times the normal working pressure of the pipeline, resulting in strong vibration of the pressure inside the lifting pipeline, which can cause the pipeline joints to disconnect, and even the pipeline to burst and the valves and fixtures to be damaged. Moreover, the reverse flow of water can also reverse the water pump, thus damaging the equipment in the pump house, seriously causing the pump house to be flooded, and even triggering major accidents such as personal injuries and deaths, affecting production and life.

[0003] Since the high-lift water pump water-lifting system can reduce the number of pump stations and the number of lifts, thereby reducing the land occupation, investment, and facilitating management and automatic control; and the high-lift pump station water-lifting system can reduce the pressure relief in the intermediate links, making the energy-saving effect remarkable. With the increasingly mature technologies of high-lift water pumps such as multistage centrifugal pumps, plunger pumps, and diaphragm pumps, more and more high-lift pump station water-lifting systems are adopted in industries such as water supply, metallurgy, chemical industry, high-rise buildings, and deep well drainage. However, the water hammer hazard of the high-lift pump station water-lifting system is much higher than that of the low-lift pump station water-lifting system, and more strict and effective water hammer protection measures must be taken.

[0004] According to Article 7.1.3 of the "Design Standard for Outdoor Water Supply" (GB50013-2018): "The accident water volume for urban water supply shall be 70% of the design water volume. The raw water transmission pipeline shall adopt more than 2 pipes, and connecting pipes shall be provided according to the accident water consumption." Therefore, if the high-lift water pump water-lifting system is used for urban water supply, a double-pipe or multi-pipe water-lifting system shall be adopted, and connecting pipes shall be provided according to the accident water consumption.

[0005] In addition, according to Article 8.1.3 of the "Technical Code for Fire Wastewater and Fire Hydrant Systems" (GB50974-2014): "The water transmission main pipes supplying water to the outdoor and indoor ring-shaped fire water supply pipe networks shall not be less than two. When one of them fails, the remaining water transmission main pipes shall still be able to meet the fire water supply design flow rate." If the high-lift water pump water-lifting system is used as the water transmission main pipe for supplying water to the ring-shaped fire water supply pipe network, a double-pipe or multi-pipe water-lifting system shall also be adopted.

[0006] Compared with the single-pipe water lifting system, the double-pipe or multi-pipe water lifting system can effectively improve the water lifting guarantee rate under accident conditions. Of course, the double-pipe or multi-pipe water lifting system is not limited to urban water supply and water supply of ring fire pipe network, but is also used in metallurgy, chemical industry, high-rise buildings and deep well drainage, which can improve the water lifting guarantee rate under accident conditions in these industries. However, the water hammer protection measures of the double-pipe or multi-pipe water lifting system are basically the same as those of the single-pipe water lifting system. Compared with the single-pipe water lifting system, since the double-pipe or multi-pipe water lifting systems can be interconnected, if the traditional water hammer protection measures are simply adopted, the water hammer effect can be transmitted between the lifting pipes or connecting pipes, so that the water hammer protection effect is weakened.

[0007] In the prior art, in order to prevent the harm of water hammer effect, some methods extend the opening and closing time of pipeline valves, that is, by setting multifunctional valves and muffler slow-closing check valves, etc., to avoid opening or closing the valves too quickly, thereby reducing the rapid changes in water flow to weaken the water hammer effect; although it can alleviate the harm caused by the water hammer effect, the cost of similar special valves increases exponentially with the increase of pipeline pressure, which forms a huge obstacle to its promotion in high-lift water pumping systems. In addition, since the pump-stop water hammer effect is mainly caused by the check valve on the outlet pipe closing too quickly, there are methods to reduce the harm of water hammer by eliminating the check valve or using a check valve with a slow-closing function such as a micro-resistance slow-closing check valve; however, eliminating the check valve can only be applied to low-lift water pumping systems, and the check valve with a slow-closing function is also difficult to apply to high-lift water pumping systems because the cost increases with the pipeline pressure. In addition, there are also methods that install water hammer eliminators near the outlet pipe of the water pump, and use the pressure of the pipe itself as power to automatically release the pressure of the water hammer eliminator to balance the local pressure and prevent the impact of water hammer on equipment and pipes; but since it can only balance the local pressure, it can protect the water pump, but it is difficult to take care of the pipe. There is also a PLC automatic control system, which monitors the pressure and flow of the pipe network, feedback controls the start, stop and speed adjustment of the water pump, and then maintains the pressure of the pipe network at a certain level to avoid excessive fluctuations, thereby reducing the occurrence of water hammer; but its various control valves and sensors lead to complex structures and cumbersome wiring, making it difficult to protect the safety and reliability of operation, and it is also necessary to set up a backup power supply to deal with the water hammer effect caused by power outages, which leads to high costs. Utility Model Content

[0008] In order to make full use of the feature that double-pipe or multi-pipe water lifting systems can be interconnected, the utility model proposes a high-lift double-pipe or multi-pipe water lifting system with enhanced water hammer protection effect, so that the water hammer protection effect of the double-pipe or multi-pipe water lifting system is not weakened but enhanced.

[0009] The present utility model is realized as follows: It includes a low-level water source, at least two lift pumps, and at least two lift pipes. The water inlet of the lift pump is connected to the low-level water source, and the water outlets are respectively connected to each lift pipe. Interconnected communicating pipes are arranged at intervals in the height direction between each lift pipe. A group of check valves are arranged at intervals in the height direction on each lift pipe. A group of check valves includes one check valve respectively arranged on each lift pipe. The upstream of any one check valve in a group of check valves shall not be connected to the downstream of other check valves in the same group.

[0010] Further, the water outlet of the lift pump is connected to one of the lift pipes. The lift pipes close to the lift pump are interconnected. A check valve is arranged on the lift pipe connected to the water outlet of the lift pump.

[0011] Further, the check valve is a micro-resistance slow-closing check valve.

[0012] Further, manual valves are respectively arranged corresponding to the upstream and downstream of each check valve on the lift pipe.

[0013] Further, the lift pump is a high-lift pump.

[0014] Further, a group of the check valves are arranged in a staggered manner in the height direction on each lift pipe.

[0015] Further, a water hammer eliminator is also arranged on the lift pipe connected to the water outlet of the lift pump. Bulges are arranged on each lift pipe, and exhaust valves are arranged on the bulges.

[0016] Further, a pressure relief valve is arranged on the communicating pipe.

[0017] Further, the motor of the lift pump is a variable-frequency control motor, and the speed of the motor of the lift pump gradually increases when starting and gradually decreases when stopping.

[0018] Compared with the prior art, the beneficial effects of the present utility model are:

[0019] 1. In the present utility model, a set of check valves is arranged on each riser pipe, and the upstream of any check valve in a set of check valves shall not communicate with the downstream of other check valves in the same set of check valves. As a result, the riser pipe can be divided into multiple segments, shortening the height where the water hammer effect occurs in the riser pipe and effectively reducing the maximum water hammer pressure acting on the riser pipe and various valves on the pipeline. Although the height where the water hammer effect acts on the riser pipe is divided into several segments by the check valves, each segment of the riser pipe can be transmitted to each other through the connecting pipe, and energy dissipation can be achieved through mutual impact during the transmission process, so that the water hammer protection effect of the double-pipe or multi-pipe water lifting system is not weakened but strengthened. In addition, through the connecting pipe arranged between each riser pipe and the set of check valves, when the closing water hammer effect occurs, the water in the lower pipe section can push the check valve open under the negative pressure of the upper pipe section and enter the upper pipe section, thereby reducing the harm of the closing water hammer to the riser pipe and the check valve and further strengthening the water hammer protection effect of the double-pipe or multi-pipe water lifting system.

[0020] 2. In the present utility model, by arranging a connecting pipe that communicates with each other between the riser pipes and cooperating with a set of check valves arranged at intervals on each riser pipe, the harm of the water hammer effect can be effectively prevented. The pure mechanical structure of the connecting pipe and the check valve has better operation reliability than that controlled by PLC, and both the connecting pipe and the check valve are relatively simple and common. Therefore, the double-pipe or multi-pipe water lifting system has a simple structure, low cost, and convenient maintenance, clearing the promotion obstacles in the high-lift water lifting system, and is also applicable to the low-lift water lifting system, with strong adaptability.

[0021] 3. In the present utility model, a set of check valves is further arranged in a staggered manner along the height direction on each riser pipe, so as to avoid the concentrated force generated by the water hammer at the connecting pipe and the occurrence of water hammer resonance, and effectively improve the reliability and service life of the water lifting system.

[0022] In summary, the present utility model has the characteristics of simple structure, safety and reliability, low cost, and convenient maintenance. Description of the Drawings

[0023] Figure 1 is one of the structural schematic diagrams of the present utility model;

[0024] Figure 2 is the second structural schematic diagram of the present utility model;

[0025] In the figure: 1 - low-level water source, 2 - lift pump, 3 - riser pipe, 4 - connecting pipe, 5 - check valve, 6 - pressure relief valve, 7 - water hammer eliminator, 8 - exhaust valve. Detailed Embodiment

[0026] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the protection scope of the present invention.

[0027] As Figure 1 and 2 shown, the present invention includes a low-level water source 1, at least two lift pumps 2 and at least two lift pipes 3. The water inlet of the lift pump 2 is communicated with the low-level water source 1, and the water outlets are respectively communicated with each lift pipe 3. Interconnected communicating pipes 4 are arranged at intervals in the height direction between the lift pipes 3. A group of check valves 5 are arranged at intervals in the height direction on each lift pipe 3. A group of check valves 5 includes one check valve 5 provided on each lift pipe 3. The upstream of any one check valve 5 in a group of check valves 5 shall not be communicated with the downstream of other check valves 5 in the same group of check valves 5.

[0028] The water outlet of the lift pump 2 is communicated with one of the lift pipes 3. The lift pipes 3 close to the lift pump 2 are interconnected. A check valve 5 is provided on the lift pipe 3 communicated with the water outlet of the lift pump 2.

[0029] The check valve 5 is a micro-resistance slow-closing check valve.

[0030] Manual valves are respectively provided on the upstream and downstream of each check valve 5 on the lift pipe 3.

[0031] The lift pump 2 is a high-lift pump.

[0032] A group of the check valves 5 are arranged in a staggered manner in the height direction on each lift pipe 3.

[0033] A water hammer eliminator 7 is also provided on the lift pipe 3 communicated with the water outlet of the lift pump 2. Bulges are provided on each lift pipe 3, and exhaust valves 8 are provided on the bulges.

[0034] A pressure relief valve 6 is provided on the communicating pipe 4.

[0035] The motor of the lift pump 2 is a variable-frequency control motor. When the motor of the lift pump 2 starts, the speed is gradually increased, and when it stops, the speed is gradually decreased.

[0036] The working principle and process of the present invention:

[0037] As Figure 2As shown in the figure, during normal water pumping, the water in the low-level water source 1 is pressurized by the lifting pump 2 to open each check valve 5 on the lifting pipe 3, and the water in the low-level water source 1 is transported to a high position through the lifting pipe 3. When the lifting pump 2 stops operating abnormally and the valve is closed (such as power failure, malfunction), the water in the lifting pipe 3 flows back downstream, causing the check valve 5 to close automatically, thus dividing the lifting pipe 3 into multiple segments, shortening the water source height where the water hammer effect occurs in the lifting pipe 3, and effectively reducing the maximum water hammer pressure acting on the lifting pipe 3 and various valves on the pipeline. At the same time, since there is a connecting pipe 4 between each lifting pipe 3 and a set of check valves 5 are arranged at different heights along the height direction on each lifting pipe 3, the water hammers generated in each lifting pipe 3 of the same section can be transmitted to each other through the connecting pipe 4, and energy dissipation is achieved through mutual impact during the transmission process, further reducing the pressure of the water hammer acting on the lifting pipe 3 and various valves on the pipeline. Moreover, when the closing water hammer occurs, the water in the lower pipe section of the lifting pipe 3 can open the check valve 5 under the action of negative pressure and enter the upper pipe section, thus effectively reducing the harm of the closing water hammer. In addition, when the water hammer effect occurs, the pressure in the pipeline can also be used as power to automatically relieve the pressure of the water hammer eliminator 7 at the outlet of the lifting pump 2 to balance the local pressure and prevent the impact of the water hammer on the lifting pump 2, thereby protecting the lifting pump 2. The exhaust valves 8 provided on the raised parts of each lifting pipe 3 can automatically and quickly discharge the air in the raised parts of the lifting pipe 3 or automatically and quickly intake air, thus eliminating the damage caused by the breakage of the water column due to the water hammer generated by pump shutdown in the lifting pipe 3 and reducing the damage to the lifting pipe 3, the lifting pump 2 and various valves.

[0038] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art, within the technical scope disclosed by the present invention, can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect, characterized in that: The invention comprises a low-level water source (1), at least two lifting pumps (2) and at least two lifting pipes (3), wherein the water inlet of the lifting pump (2) is connected to the low-level water source (1), and the water outlet is respectively connected to each lifting pipe (3), and connecting pipes (4) which are connected to each other are arranged at intervals along the height direction between each lifting pipe (3), and each lifting pipe (3) is provided with a group of check valves (5) at intervals along the height direction, wherein a group of check valves (5) comprises a check valve (5) respectively arranged on each lifting pipe (3), and the upstream of any check valve (5) in a group of check valves (5) shall not be connected to the downstream of other check valves (5) in the same group of check valves (5).

2. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 1, characterized in that: The water outlet of the lift pump (2) is connected to one of the lift pipes (3), and the lift pipes (3) close to the lift pump (2) are connected to each other. A check valve (5) is provided on the lift pipe (3) connected to the water outlet of the lift pump (2).

3. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 1, characterized in that: The check valve (5) is a micro-resistance slow-closing check valve.

4. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 1, characterized in that: Manual valves are respectively provided on the lifting pipe (3) upstream and downstream of each check valve (5).

5. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 1, characterized in that: The lift pump (2) is a high-lift lift pump.

6. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to any one of claims 1 to 5, characterized in that: A group of check valves (5) are arranged on each riser (3) in a staggered manner along the height direction.

7. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 6, characterized in that: A water hammer arrester (7) is also provided on the lifting pipe (3) connected to the water outlet of the lifting pump (2), and each lifting pipe (3) is provided with a raised portion, and an exhaust valve (8) is provided on the raised portion.

8. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 6, characterized in that: The connecting pipe (4) is provided with a pressure relief valve (6).

9. The high-lift double-pipe or multi-pipe water pumping system with enhanced water hammer protection effect according to claim 6, characterized in that: The motor of the lift pump (2) is a variable frequency controlled motor, and the rotation speed of the motor of the lift pump (2) gradually increases when it is started and gradually decreases when it is stopped.

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