Cavitation-preventing device of double-suction centrifugal pump

Abstract

The utility model relates to the technical field of centrifugal pumps, and discloses a double-suction centrifugal pump anti-cavitation device which comprises a bottom plate, the middle side of the top of the bottom plate is fixedly connected with a pump body, the rear side of the pump body is fixedly connected with a motor, the output end of the motor is fixedly connected with a rotating shaft, and the side, away from the motor, of the rotating shaft is fixedly connected with an eccentric wheel. An impeller is arranged on the outer wall of the rotating shaft, a pressurizing assembly is arranged on the front side of the top of the bottom plate and comprises a barrel, the barrel is fixedly connected to the front side of the top of the bottom plate, a piston is slidably connected to the interior of the barrel, a connecting rod is fixedly connected to the top of the piston, and an extrusion plate is fixedly connected to the top of the connecting rod. According to the utility model, through the design of the pressurizing assembly, the eccentric wheel is used for driving the extrusion plate and the piston to periodically move in the cylinder body, and gas is compressed and fed into the water inlet of the pump body through the exhaust pipe, so that the pressure at the water inlet is effectively improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to centrifugal pump technical field especially relates to a double suction centrifugal pump anti cavitation device. BACKGROUND

[0002] In many industrial and civil fields, double suction centrifugal pumps are widely used in liquid transportation, such as liquid material transportation in industrial production, urban water supply and drainage system, agricultural irrigation and building fire fighting system etc. Double suction centrifugal pumps have the advantages of large flow and high lift, which can meet the liquid transportation demand in different scenes. However, in the actual use process, double suction centrifugal pumps often encounter cavitation problem during operation. Cavitation refers to the phenomenon that when the pressure of liquid at the impeller inlet is lower than the saturated vapor pressure, the dissolved gas in the liquid escapes to form bubbles. These bubbles will then collapse in the high pressure area, producing strong impact force, which will cause erosion and damage to the flow parts such as impeller and pump shell. Cavitation not only reduces the efficiency of double suction centrifugal pump, but also causes the vibration and noise of the pump to increase, which seriously affects the service life and performance of double suction centrifugal pump.

[0003] The traditional method to solve the cavitation problem often has certain limitations. Some methods only adjust the shape of the impeller or the internal flow passage of the pump body, but this optimization may affect the hydraulic performance of the pump to some extent, and cannot effectively prevent the occurrence of cavitation phenomenon in some extreme working conditions. Some others prevent cavitation by increasing the inlet pressure of the whole system, but this will increase the energy consumption of the system and the complexity of the equipment. Therefore, a double suction centrifugal pump anti cavitation device is proposed. UTILITY MODEL CONTENT

[0004] In order to make up for the above shortcomings, the utility model provides a double suction centrifugal pump anti cavitation device, which aims at improving the problem that the traditional method to solve the cavitation problem in the prior art often has certain limitations.

[0005] In order to achieve the above purpose, the utility model adopts the following technical scheme: a double suction centrifugal pump anti cavitation device, comprising a bottom plate, the top middle side of the bottom plate is fixedly connected with a pump body, the rear side of the pump body is fixedly connected with a motor, the output end of the motor is fixedly connected with a rotating shaft, the side away from the motor of the rotating shaft is fixedly connected with an eccentric wheel, the outer wall of the rotating shaft is provided with an impeller, the top front side of the bottom plate is provided with a pressurizing assembly;

[0006] The pressurizing assembly comprises a cylinder body fixedly connected to the top front side of the bottom plate, a piston slidably connected inside the cylinder body, a connecting rod fixedly connected to the top of the piston, an extrusion plate fixedly connected to the top of the connecting rod, a first spring fixedly connected to the bottom of the extrusion plate, an electromagnetic one-way valve and a check valve fixedly connected to the bottom of the cylinder body, an air inlet pipe mounted on the outer wall of the electromagnetic one-way valve, and an air outlet pipe mounted on the bottom of the check valve.

[0007] Further description of the above technical solution:

[0008] The filter assembly comprises a filter box arranged on the air inlet pipe, a filter screen mounted inside the filter box, and a fixing assembly arranged inside the filter box.

[0009] Further description of the above technical solution:

[0010] The fixing assembly comprises two pressing rods and two clamping rods, the outer walls of the pressing rods and the clamping rods are slidably connected inside the filter box, the outer wall of the pressing rod is fixedly connected with a limiting block, the outer wall of the pressing rod is sleeved with a second spring, the outer wall of the clamping rod is fixedly connected with an inclined block, and the side of the clamping rod away from the filter screen is provided with a third spring.

[0011] Further description of the above technical solution:

[0012] The left side of the pump body is provided with a water inlet, and the right side of the pump body is provided with a water outlet.

[0013] Further description of the above technical solution:

[0014] The protruding part of the rotating shaft is attached to the top of the extrusion plate, and the end of the air outlet pipe away from the check valve is arranged inside the water inlet.

[0015] Further description of the above technical solution:

[0016] The bottom plate is provided with a controller, and the controller is electrically connected with the electromagnetic one-way valve.

[0017] Further description of the above technical solution:

[0018] The end of the clamping rod away from the third spring is clamped with the filter screen, and the bottom of the pressing rod is attached to the top of the inclined block.

[0019] Further description of the above technical solution:

[0020] The end of the second spring away from the limiting block is fixedly connected to the inner wall of the filter box, and the end of the third spring away from the clamping rod is fixedly connected to the inner wall of the filter box.

[0021] The utility model has the advantages of the following:

[0022] 1. In the utility model, the periodic motion of the eccentric wheel, the extrusion plate and the piston in the cylinder is utilized to compress the gas and send it into the water inlet of the pump body through the exhaust pipe, so as to effectively improve the pressure at the water inlet. The pressure increase can prevent the dissolved gas in the liquid from being precipitated to form bubbles due to the excessively low pressure when the low-pressure area is generated by the rotation of the impeller, thereby avoiding the occurrence of the cavitation phenomenon.

[0023] 2. In the utility model, the filter screen in the filter assembly can effectively intercept the impurity particles in the entering gas, so as to prevent the impurities from entering the pressurizing assembly and the pump body. The cleanliness of the gas is ensured, and the component wear caused by the impurities is avoided. Meanwhile, the elastic restoring force of the second spring and the third spring and the cooperation of the inclined block and the clamping rod can be utilized to conveniently release the clamping of the clamping rod on the filter screen, so as to realize the easy dismounting and mounting operation of the filter screen. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 FIG. 1 is a perspective view of the anti-cavitation device for the double-suction centrifugal pump according to the utility model;

[0025] Figure 2 FIG. 2 is a motor view of the anti-cavitation device for the double-suction centrifugal pump according to the utility model;

[0026] Figure 3 FIG. 3 is a sectional view of the cylinder of the anti-cavitation device for the double-suction centrifugal pump according to the utility model;

[0027] Figure 4 FIG. 4 is a sectional view of the filter box of the anti-cavitation device for the double-suction centrifugal pump according to the utility model; Figure 1 FIG. 5 is an enlarged view of position A in FIG. 4;

[0028] Figure 5 FIG. 6 is an enlarged view of position B in FIG. 4.

[0029] LEGEND

[0030] 1. bottom plate; 2. pump body; 3. motor; 4. rotating shaft; 5. eccentric wheel; 6. cylinder; 7. piston; 8. connecting rod; 9. extrusion plate; 10. first spring; 11. electromagnetic check valve; 12. air inlet pipe; 13. check valve; 14. exhaust pipe; 15. filter box; 16. filter screen; 17. pressing rod; 18. limiting block; 19. second spring; 20. clamping rod; 21. inclined block; 22. third spring; 23. water inlet; 24. water outlet; 25. controller. DETAILED DESCRIPTION

[0031] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0032] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. Figures 1-3 The utility model provides an embodiment: a kind of dual suction centrifugal pump anti cavitation device, including bottom plate 1, bottom plate 1 as the basis supporting component of entire dual suction centrifugal pump anti cavitation device, provide stable installation base for the pump body 2, motor 3 and other components on it, ensure the stability and reliability of entire device in the process of operation, bottom plate 1 top middle side is fixedly connected with pump body 2, pump body 2 is the core component of dual suction centrifugal pump, responsible for realizing liquid suction and discharge operation, motor 3 is fixedly connected in pump body 2 rear side, motor 3 is driven device, provides power source for entire dual suction centrifugal pump anti cavitation device, motor 3 output end is fixedly connected with rotating shaft 4, rotating shaft 4 is the key component of connecting motor 3 and impeller, it passes on rotating power generated by motor 3 to impeller, so that impeller can rotate at high speed in pump body 2. Rotating shaft 4 is fixedly connected with eccentric wheel 5 in the side away from motor 3, eccentric wheel 5 will produce periodic motion when rotating shaft 4 rotates, rotating shaft 4 outer wall is provided with impeller, when rotating shaft 4 rotates under the drive of motor 3, impeller rotates along with it, drives liquid in pump body 2 to rotate together, to realize liquid suction and discharge function, bottom plate 1 top front side is provided with pressurizing assembly, pressurizing assembly carries out pressure regulation to liquid in pump body 2, increases the pressure of liquid, avoids cavitation phenomenon caused by too low pressure;

[0033] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. Figures 1-3The pressurizing assembly comprises a cylinder body 6 fixedly connected to the top front side of the bottom plate 1, which provides a containing space for the pressurizing assembly, and a piston 7 slidably connected inside the cylinder body 6, which can reciprocate inside the cylinder body 6 to realize the compression and storage of gas. The piston 7 is slidably connected inside the cylinder body 6. When the piston 7 moves downward, the gas in the cylinder body 6 is compressed. When the piston 7 moves upward, a negative pressure is formed in the cylinder body 6 to suck in gas, realizing the suction and compression of gas. The piston 7 is fixedly connected to a connecting rod 8 at the top, which is used to connect the piston 7 and the extrusion plate 9 to transmit the movement of the extrusion plate 9 to the piston 7. The extrusion plate 9 is fixedly connected to the connecting rod 8 at the top. When the shaft 4 rotates the eccentric wheel 5, the eccentric wheel 5 will periodically push the extrusion plate 9 to move up and down, thereby driving the piston 7 to move up and down in the cylinder body 6. The extrusion plate 9 is fixedly connected to the first spring 10 at the bottom. When the extrusion plate 9 is extruded downward by the eccentric wheel 5, the first spring 10 is compressed to store elastic potential energy. When the eccentric wheel 5 no longer applies pressure to the extrusion plate 9, the first spring 10 releases the elastic potential energy to push the extrusion plate 9 back to position, making the movement of the piston 7 more stable. The cylinder body 6 is fixedly connected to the electromagnetic one-way valve 11 and the check valve 13 at the bottom. The electromagnetic one-way valve 11 is installed with an air inlet pipe 12 at the bottom. The electromagnetic one-way valve 11 is controlled to open and close by magnetism. When it is opened, it allows gas to enter the cylinder body 6 from the air inlet pipe 12. When it is closed, it prevents gas from flowing back, ensuring that gas can only flow into the cylinder body 6 in one direction. The check valve 13 is installed with an air outlet pipe 14 at the bottom. The check valve 13 prevents gas in the air outlet pipe 14 from flowing back into the cylinder body 6. The air inlet pipe 12 is provided with a filter assembly on the outer wall. The filter assembly can filter the incoming gas to prevent impurities from entering the pressurizing assembly, ensuring the normal operation and service life of the pressurizing assembly, and avoiding blockage or damage caused by impurities.

[0034] With reference to Figure 4 The filter assembly comprises a filter box 15 arranged on the air inlet pipe 12. The filter box 15 provides installation space for the filter screen 16 and the fixing assembly, ensuring that the gas can be effectively filtered before entering the air inlet pipe 12. The filter box 15 is installed with the filter screen 16 inside. The filter screen 16 filters the gas entering the air inlet pipe 12 and intercepts impurity particles in the gas. The filter box 15 is provided with a fixing assembly inside. The fixing assembly is used to fix the filter screen 16, ensuring the stability of the position of the filter screen 16 during work, and facilitating the installation and removal of the filter screen 16.

[0035] With reference to Figure 5The fixed assembly comprises two pressing rods 17 and two clamping rods 20, the outer walls of the pressing rods 17 and the clamping rods 20 are slidingly connected in the filter box 15, when the filter screen 16 needs to be replaced or cleaned, the pressing rods 17 can be pressed to slide, thereby releasing the fixation of the filter screen 16, facilitating the maintenance operation of the filter screen 16. The outer wall of the pressing rod 17 is fixedly connected with a limiting block 18, the limiting block 18 is used for limiting the sliding stroke of the pressing rod 17, ensuring that the pressing rod 17 moves within a certain range, the outer wall of the pressing rod 17 is sleeved with a second spring 19, when the pressing rod 17 is pressed, the second spring 19 is compressed to store elastic potential energy; when the external force disappears, the second spring 19 releases the elastic potential energy to push the pressing rod 17 back to the original state, providing elastic restoring force for the operation of the fixed assembly, ensuring the convenience and reliability of the operation of the fixed assembly, the outer wall of the clamping rod 20 is fixedly connected with an inclined block 21, when the pressing rod 17 is pressed downward, the clamping rod 20 is pushed to slide through the interaction with the inclined block 21, thereby releasing the clamping of the filter screen 16 by the clamping rod 20, the side, away from the filter screen 16, of the clamping rod 20 is provided with a third spring 22, when the filter screen 16 needs to be replaced or cleaned, the clamping of the clamping rod 20 can be released by pressing the pressing rod 17 to overcome the elastic force of the third spring 22, after the operation is completed, the third spring 22 pushes the clamping rod 20 back to ensure the automatic resetting function of the fixed assembly.

[0036] With reference to Figure 1 and Figure 2 , the left side of the pump body 2 is provided with a water inlet 23, the water inlet 23 is the inlet of the double-suction centrifugal pump for sucking liquid, the liquid enters the pump body 2 from the water inlet 23, is sucked under the rotation of the impeller and obtains energy, the right side of the pump body 2 is provided with a water outlet 24, the water outlet 24 is the outlet of the double-suction centrifugal pump for discharging the liquid pressurized by the impeller, ensuring that the liquid can be delivered to the required place.

[0037] With reference to Figures 1-3 , the convex part of the rotating shaft 4 and the top of the extrusion plate 9 are in close contact, when the rotating shaft 4 drives the eccentric wheel 5 to rotate, the eccentric wheel 5 can accurately push the extrusion plate 9 to move up and down, ensuring the reliability and accuracy of the power transmission of the pressurizing assembly. The end, away from the check valve 13, of the exhaust pipe 14 is arranged in the water inlet 23, so that the pressurized gas discharged from the cylinder body 6 can directly enter the water inlet 23, increasing the pressure at the water inlet 23, effectively preventing the formation of air bubbles due to the low pressure at the water inlet 23, and improving the anti-cavitation ability of the pump body 2.

[0038] With reference to Figures 1-3 , the bottom plate 1 is provided with a controller 25, the controller 25 is electrically connected with the electromagnetic one-way valve 11, through the intelligent control of the controller 25, the accurate adjustment of the air inlet of the air inlet pipe 12 can be realized, so that the pressurizing assembly can suck air in time as needed, ensuring the accuracy and effectiveness of the entire pressurizing process.

[0039] With reference toFigure 5 The clamping rod 20 is clamped to the filter screen 16 away from one end of the third spring 22, ensuring that the filter screen 16 is firmly fixed in the filter box 15 during normal operation, preventing the filter screen 16 from being displaced or falling due to the impact of gas flow or other external forces. The pressing rod 17 is in contact between the bottom and the top of the inclined block 21, and when the pressing rod 17 is pressed down, the clamping rod 20 can be pushed to slide through the interaction with the inclined block 21, thereby achieving the disassembly and installation operation of the filter screen 16.

[0040] Referring to Figure 5 The second spring 19 is fixedly connected to the inner wall of the filter box 15 away from the limiting block 18, ensuring that the movement trajectory and range of the pressing rod 17 are effectively controlled, ensuring the operation stability of the entire fixing assembly. The third spring 22 is fixedly connected to the inner wall of the filter box 15 away from one end of the clamping rod 20, ensuring the convenience of the installation and disassembly operation of the filter screen 16, and also ensuring the position stability of the filter screen 16 during normal operation.

[0041] Working principle: when the double-suction centrifugal pump is started, the motor 3 is energized to start, and the motor 3 drives the rotating shaft 4 to rotate after starting, and then drives the impeller to rotate. The rotation of the impeller generates centrifugal force on the liquid in the pump body 2, forming a low-pressure area at the center of the impeller. The liquid is sucked from the water inlet 23 and discharged from the water outlet 24 after being energized by the impeller. The rotating shaft 4 rotates while driving the eccentric wheel 5 to rotate, which drives the extrusion plate 9 to move up and down. The extrusion plate 9 drives the piston 7 to slide in the cylinder 6 through the connecting rod 8. When the extrusion plate 9 moves downward, the piston 7 slides downward in the cylinder 6. At this time, the gas in the cylinder 6 is compressed, and the pressure increases. The gas pressure inside the cylinder 6 is discharged through the check valve 13 and the exhaust pipe 14, and at the same time, the first spring 10 connected to the bottom of the extrusion plate 9 is compressed, storing elastic potential energy. When the movement of the eccentric wheel 5 causes the extrusion plate 9 to move upward, the first spring 10 releases the elastic potential energy, pushing the extrusion plate 9 and the piston 7 to reset, forming a negative pressure in the cylinder 6, thereby supplementing the gas pressure inside the cylinder 6 through the electromagnetic one-way valve 11 and the air inlet pipe 12.

[0042] When the gas enters the inside of the cylinder 6, it will first pass through the filter screen 16 inside the filter box 15 to filter the impurities in the air. When it is necessary to replace or clean the filter screen 16, press the pressing rod 17, and the pressing rod 17 slides downward against the elastic force of the second spring 19, the bottom of the pressing rod 17 pushes the inclined block 21, and then pushes the clamping rod 20 to slide against the elastic force of the third spring 22, releasing the clamping of the clamping rod 20 to the filter screen 16. At this time, the filter screen 16 can be easily taken out for maintenance operation. After maintenance is completed, the pressing rod 17 is loosened, and the second spring 19 and the third spring 22 reset the pressing rod 17 and the clamping rod 20 respectively, and the filter screen 16 is fixed again.

[0043] Finally, it should be noted that: the above only for the preferred embodiments of the present application, and is not intended to limit the present application, although the foregoing embodiments of the present application has been described in detail, for the skilled in the art, it still can be modified, or for part of the technical features of the equivalent replacement, the spirit and principles of the present application, made any modification, equivalent replacement, improvement, etc., should be included within the scope of the present application.

Claims

1. A dual suction centrifugal pump anti-cavitation device comprising a base plate (1), characterized in that: The bottom plate (1) top middle side is fixedly connected with the pump body (2), the pump body (2) rear side is fixedly connected with motor (3), the motor (3) output is fixedly connected with the rotating shaft (4), the rotating shaft (4) is fixedly connected with eccentric wheel (5) away from the motor (3) side, the rotating shaft (4) outer wall is provided with impeller, the bottom plate (1) top front side is provided with pressurizing assembly; The pressurizing assembly includes a cylinder (6), the cylinder (6) is fixedly connected on the top front side of the bottom plate (1), the piston (7) is slidably connected in the cylinder (6), the connecting rod (8) is fixedly connected on the top of the piston (7), the extrusion plate (9) is fixedly connected on the top of the connecting rod (8), the first spring (10) is fixedly connected on the bottom of the extrusion plate (9), the electromagnetic one-way valve (11) and the check valve (13) are fixedly connected on the bottom of the cylinder (6), the air inlet pipe (12) is installed on the bottom of the electromagnetic one-way valve (11), the exhaust pipe (14) is installed on the bottom of the check valve (13), the filter assembly is arranged on the outer wall of the air inlet pipe (12).

2. The anti-cavitation device of claim 1, wherein: The filter assembly includes a filter box (15), the filter box (15) is arranged on the air inlet pipe (12), the filter screen (16) is installed in the filter box (15), and the fixing assembly is arranged in the filter box (15).

3. The anti-cavitation device of claim 2, wherein: The fixing assembly includes two pressing rods (17) and two clamping rods (20), the pressing rods (17) and the clamping rods (20) are slidably connected in the filter box (15), the limiting block (18) is fixedly connected on the outer wall of the pressing rod (17), the second spring (19) is sleeved on the outer wall of the pressing rod (17), the inclined block (21) is fixedly connected on the outer wall of the clamping rod (20), and the third spring (22) is arranged on the side, away from the filter screen (16), of the clamping rod (20).

4. The anti-cavitation device of claim 1, wherein: The water inlet (23) is formed in the left side of the pump body (2), and the water outlet (24) is formed in the right side of the pump body (2).

5. The anti-cavitation device of claim 4, wherein: The protruding part of the rotating shaft (4) is attached to the top of the extrusion plate (9), and one end of the exhaust pipe (14), away from the check valve (13), is arranged in the water inlet (23).

6. The anti-cavitation device of claim 1, wherein: The controller (25) is installed on the bottom plate (1), and the controller (25) and the electromagnetic one-way valve (11) are electrically connected.

7. The anti-cavitation device of a double-suction centrifugal pump according to claim 3, characterized in that: The end, away from the third spring (22), of the clamping rod (20) is clamped with the filter screen (16), and the bottom of the pressing rod (17) is attached to the top of the inclined block (21).

8. The anti-cavitation device of claim 3, wherein: One end of the second spring (19), away from the limiting block (18), is fixedly connected to the inner wall of the filter box (15), and one end of the third spring (22), away from the clamping rod (20), is fixedly connected to the inner wall of the filter box (15).

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