Direct-connection horizontal cantilever double-suction pump

Abstract

The utility model discloses a direct-connection horizontal cantilever double-suction pump which comprises a pump body, a pump cover and a motor, and further comprises a double-suction impeller arranged in the pump body and a suction inlet formed in the end of the pump body in the horizontal direction, a flow dividing partition plate is arranged in the suction inlet, and a flow channel of the suction inlet is divided into two flow dividing flow channels by the flow dividing partition plate. One end of the straight connecting shaft is connected with the motor, and the other end of the straight connecting shaft penetrates through the pump body and is connected with the double-suction impeller; according to the utility model, the two sides of the double-suction impeller are symmetrical, so that the axial forces are mutually counteracted to realize balance; meanwhile, a flow channel of the suction inlet is divided into two flow dividing flow channels by the flow dividing partition plate, so that liquid can equally divide the total flow of the pump body from inlets in the two sides of the double-suction impeller, the cavitation specific speed is reduced, and the risk that the pump generates cavitation is reduced; the motor and the pump body are directly connected through the straight connecting shaft, a pump body rotating shaft and a motor main shaft are integrated, the length of a pump body unit shaft system and the overall length of the unit are reduced, and the occupied area of the pump is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of double-suction pumps, in particular to a direct-connected horizontal cantilever double-suction pump. Background Art

[0002] Due to the advantages of simple structure, wide application and easy maintenance, single-stage single-suction cantilever pumps are widely used in construction, water treatment and other fields, and are usually used to transport large amounts of clean water, circulating water, cooling water and other liquids. Single-stage single-suction horizontal cantilever pumps use only one impeller set in the center of the pump body, sucking the liquid from one side of the impeller, and discharging the liquid from the outlet located in the center of the pump body through the rotation of the impeller.

[0003] The impeller of the existing single-stage single-suction cantilever pump adopts a single suction inlet structure, which leads to asymmetry of the front and rear covers of the impeller. Therefore, the forces that the front and rear covers of the impeller can withstand are inconsistent. When the liquid enters the impeller, a force pointing to the inlet will be generated, namely the axial force. The existence of axial force is very harmful to the pump. The unbalanced axial force will increase the workload of the bearing, causing rapid wear or even damage to the bearing, affecting the normal operation of the pump body. At the same time, under the same flow rate, the volume of the single-stage single-suction cantilever pump increases significantly, resulting in a significant increase in the pump shaft load, resulting in reduced efficiency and hidden dangers in safe operation; under the same parameters, the single-stage single-suction cantilever pump has a large specific speed and a small impeller blade inlet area. The impeller has a potential risk of cavitation, resulting in reduced operating reliability.

[0004] In order to solve the above problems, a balancing hole or a rear ring is usually added to the impeller to increase the blade inlet area, or the single-suction pump is replaced with a horizontal split double-suction pump with the same parameters.

[0005] For example, a Chinese patent with the publication number CN 211174737 U discloses an axial force balancing structure of a single-stage single-suction cantilever centrifugal pump, which includes a pump body 1', an impeller 4', a pump cover 5' and a pump shaft 10'. The impeller 4' is installed in the pump body 1', and the pump body 1' is connected to the bearing box 9' through the pump cover 5'. The impeller 4' is fixed on the pump shaft 10' in the pump body 1'. The impeller 4' consists of an impeller front cover plate 11', an impeller rear cover plate 12', blades and auxiliary blades 13'. A plurality of balancing holes 14' are added on the impeller rear cover plate 12'; the diameter of the auxiliary blades 13' on the impeller rear cover plate 12' is increased by 15% compared with the original auxiliary blade diameter, such as Figure 1a and Figure 1b shown.

[0006] However, although adding a balancing hole to the impeller has a better axial force balancing ability, the leakage and backflow problems of the balancing hole itself will lead to a decrease in impeller efficiency and then an increase in unit power, thereby increasing costs; and although increasing the blade inlet area can achieve improved cavitation resistance, under the same parameters, to achieve this goal, it is bound to significantly increase the radial size of the impeller, increase the overall size of the impeller, and increase the mass, thereby leading to potential operating risks of the cantilever pump and increased processing and manufacturing costs; further, using a double-suction pump with the same parameters as a substitute, although it solves the above problems, its components are configured in large quantities and the cost is high, the product is large in size, and occupies a large area, which significantly increases the processing and manufacturing cost and installation space.

[0007] Therefore, how to effectively balance the axial force of the cantilever pump, reduce the risk of cavitation, and make the cantilever pump compact and stable in operation has become an urgent problem to be solved in this field. Utility Model Content

[0008] In view of the defects of the prior art, the purpose of the utility model is to provide a direct-connected horizontal cantilever double-suction pump which can balance the axial force, reduce the risk of cavitation and has a compact structure.

[0009] In order to achieve the above object, the utility model provides a direct-connected horizontal cantilever double-suction pump, comprising

[0010] Pump body,

[0011] a pump cover disposed on the pump body, and

[0012] The electric motor also includes

[0013] A double-suction impeller is arranged in the pump body,

[0014] A suction port is arranged at the end of the pump body in a horizontal direction, and a flow dividing partition is arranged in the suction port, and the flow dividing partition divides the flow channel of the suction port into two flow dividing flow channels,

[0015] A direct-connection shaft connected to the motor, one end of the direct-connection shaft is connected to the motor, and the other end passes through the pump body and is connected to the double-suction impeller.

[0016] A discharge port is provided on the pump body and is perpendicular to the suction port.

[0017] Furthermore, sealing rings are provided on both side inlets of the double-suction impeller, and the sealing rings are connected to the pump body by interference fit.

[0018] Furthermore, the direct-connection shaft is formed by the main shaft of the motor.

[0019] Furthermore, a water retaining ring is provided at the connection between the direct-connection shaft and the pump body.

[0020] Furthermore, it also includes a container-type mechanical seal arranged on the pump body.

[0021] Furthermore, the rotating component of the cartridge mechanical seal is arranged on the direct-connection shaft.

[0022] Furthermore, a sealing flushing pipe component is provided on the discharge port.

[0023] Furthermore, one end of the sealing flushing pipe component is connected to the discharge port, and the other end is connected to the containerized mechanical seal.

[0024] Furthermore, it also includes a unit base, and the unit base is used to support the motor and the pump body.

[0025] Furthermore, the pump cover is composed of an annular hydraulic structure.

[0026] The utility model provides a direct-connected horizontal cantilever double-suction pump, which adopts a double-suction impeller arranged in a pump body. Since the double-suction impeller is symmetrical on both sides, the axial forces offset each other to achieve balance, so there is no need to set a balancing hole, so as to reduce pump body leakage and improve operating efficiency.

[0027] At the same time, the direct-connected horizontal cantilever double-suction pump provided by the utility model is provided with a diversion baffle in the suction port to divide the flow channel of the suction port into two diversion flow channels, so that the liquid can enter the two side inlets of the double-suction impeller from the suction port respectively, and the two side inlets equally divide the total flow entering the pump body. Under the condition of unchanged head, the cavitation specific speed is reduced, thereby reducing the risk of cavitation in the pump.

[0028] Furthermore, the direct-connected horizontal cantilever double-suction pump provided by the utility model adopts a direct-connected shaft to directly connect the motor and the pump body, integrating the pump body rotating shaft and the motor main shaft. There is no need to align the pump body rotating shaft and the motor main shaft through a coupling, thereby reducing the axial length of the pump body unit shaft system and the overall unit, effectively reducing the footprint of the pump, and making the pump body structure compact. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is further described below in conjunction with the accompanying drawings and specific implementations.

[0030] Figure 1a and Figure 1b It is a structural schematic diagram of an existing single-stage single-suction cantilever centrifugal pump;

[0031] Figure 2 This is a cross-sectional view of the overall structure of the direct-connected horizontal cantilever double-suction pump provided by the utility model;

[0032] Figure 3 It is a side view of the direct-connected horizontal cantilever double-suction pump in the utility model;

[0033] Reference numerals:

[0034] 1. Rotor components; 2. Pump body; 21. Suction port; 22. Discharge port; 23. Flow channel; 231. First branch flow channel; 232. Second branch flow channel; 24. Branch baffle; 3. Sealing ring; 4. Double-suction impeller; 41. First inlet; 42. Second inlet; 5. Pump cover; 6. Integrated mechanical seal; 7. Sealing flushing pipe components; 8. Motor; 81. Direct-connected shaft; 9. Unit base; 10. Water retaining ring. DETAILED DESCRIPTION

[0035] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to specific illustrations.

[0036] See also Figure 2 and Figure 3 , which shows an example of a direct-connected horizontal cantilever double-suction pump provided by the utility model.

[0037] As can be seen from the figure, the direct-connected horizontal cantilever double-suction pump of this example mainly includes a pump body 2, a pump cover 5, a motor 8 and a unit base 9.

[0038] The pump body 2 and the motor 8 are arranged on the unit base 9. The pump body 2 is provided with a pump cover 5 and is connected to the motor 8. The motor 8 is configured to drive the pump body 2 to suck liquid from the suction port 21 and discharge the liquid from the discharge port 22.

[0039] Among them, the suction port 21 is arranged in the horizontal direction of the end of the pump body 2, and the discharge port 22 is arranged in the vertical direction of the pump body 2. In order to allow the liquid to enter the suction port 21 horizontally, the pump body 2 can drive the liquid to be discharged from the vertical discharge port 22, and a double-suction impeller 4 is provided in the pump body 2.

[0040] The double-suction impeller 4 is arranged in the middle of the pump body 2, and a first inlet 41 and a second inlet 42 are respectively provided on both sides of the double-suction impeller 4. The first inlet 41 and the second inlet 42 have the same structure and opposite directions, and are arranged in the same horizontal direction as the suction port 21, so that the liquid in the suction port 21 can enter the double-suction impeller 4 through the flow channel 23 of the suction port 21.

[0041] Furthermore, a diverter baffle 24 is provided in the suction port 21, and the diverter baffle 24 is arranged at the top of the first inlet 41 of the double-suction impeller 4, dividing the flow channel 23 into a first diverter flow channel 231 and a second diverter flow channel 232. The first diverter flow channel 231 connects the suction port 21 and the first inlet 41 of the double-suction impeller 4, and the second diverter flow channel 232 connects the suction port 21 and the second inlet 42, so that when the blades of the double-suction impeller 4 rotate, the liquid in the suction port 21 can flow to the first diverter flow channel 231 and the second diverter flow channel 232 respectively through the diverter baffle 24, thereby entering the double-suction impeller 4 from the first inlet 41 and the second inlet 42 respectively.

[0042] As the blades of the double-suction impeller 4 rotate, the liquid sucked into the first inlet 41 and the second inlet 42 generates centrifugal force to increase its flow energy. The pressure difference generated in the double-suction impeller 4 pushes the liquid toward the discharge port 22 so that the liquid is discharged from the discharge port 22.

[0043] At the same time, the flow dividing baffle 24 buffers the liquid entering the suction port 21, which can effectively reduce the impact and vortex loss of the liquid flow before entering the double-suction impeller 4, and reduce the potential risk of vibration and noise of the pump.

[0044] In order to prevent the liquid from generating a large amount of vortex loss due to the collision with the inner wall of the pump cover 5 when entering the second inlet 42 through the second diversion channel 232, the pump cover 5 is configured to be composed of annular hydraulic structure, and its inner wall is annular. Therefore, when the liquid enters the second diversion channel 232, the flow energy on the annular inner wall of the pump cover 5 reduces the vortex loss and flows into the second inlet 42 along the internal ring.

[0045] Therefore, since the inlet structures on both sides of the double-suction impeller 4 are identical and symmetrical, the axial force can be effectively balanced. At the same time, due to the bidirectional design of the double-suction impeller 4, the pressure inside the double-suction impeller 4 is relatively uniform, so that the stability of the liquid flow is improved. At the same time, the flow dividing baffle 24 divides the liquid entering the suction port 21 into two parts, which enter the double-suction impeller 4 from the inlets on both sides of the double-suction impeller 4, and divides the total flow entering the pump equally, so as to reduce the cavitation specific speed, thereby reducing the risk of cavitation in the pump.

[0046] Furthermore, sealing rings 3 are provided on the first inlet 41 and the second inlet 42 on both sides of the double-suction impeller 4. The sealing ring 3 is connected to the pump body 2 by interference fit, so that when the sealing leakage gap of the double-suction impeller 4 increases due to water erosion after long-term operation, the sealing ring 3 can further seal the double-suction impeller 4 to avoid efficiency reduction due to leakage of the double-suction impeller 4.

[0047] Since the double-suction impeller 4 uses suction ports on both sides to increase the volume of the pump body 2, in order to reduce the overall footprint of the pump, make its structure compact and reduce manufacturing costs, the pump body 2 is connected to the motor 8 through a direct-connection shaft 81.

[0048] The direct-connection shaft 81 is composed of the main shaft of the motor 8, one end of which is connected to the motor 8, and the other end passes through the pump body 2 to be connected to the double-suction impeller 4. The direct-connection shaft 81 directly connects the pump body 2 and the motor 8, and there is no need to align the rotating shaft of the pump body 2 and the main shaft of the motor 8 through a coupling, thereby reducing the axial length of the pump body unit shaft system and the entire unit, effectively reducing the footprint of the pump, and making the pump body structure compact.

[0049] Furthermore, when the direct-connection shaft 81 rotates, the liquid will leak through the gap at the connection between the pump body 2 and the direct-connection shaft 81. An integrated mechanical seal 6 and a water retaining ring 10 are provided at the connection between the direct-connection shaft 81 and the pump body 2 to seal the direct-connection shaft 81 to effectively prevent leakage of the pump body 2 and improve the working efficiency of the pump.

[0050] Therefore, the rotor component 1 composed of the double-suction impeller 4, the integrated mechanical seal 6 rotating components and the main shaft of the motor 8 (directly connected shaft 81) greatly reduces the axial length of the unit shaft system and the entire unit while improving the operating reliability, effectively reducing the pump footprint.

[0051] Furthermore, a sealing flushing pipe component 7 is provided on the discharge port 22, one end of the sealing flushing pipe component 7 is connected to the discharge port 22, and the other end is connected to the integrated mechanical seal 6, so that part of the liquid in the discharge port 22 can enter the integrated mechanical seal 6 through the sealing flushing pipe component 7 to flush the integrated mechanical seal 6, so as to effectively reduce the temperature of the friction surface in the integrated mechanical seal 6 and reduce the friction coefficient, thereby improving the sealing effect of the mechanical seal and reducing leakage.

[0052] The direct-connected horizontal cantilever double-suction pump provided by the utility model adopts a double-suction impeller 4 to effectively balance the axial force, and a diversion baffle is arranged at the suction port 21 to divide the total flow entering the pump body equally, so that the liquid enters the double-suction impeller 4 from the inlets on both sides, reducing the cavitation specific speed, thereby reducing the risk of cavitation in the pump. At the same time, a direct-connected shaft 81 is used to connect the pump body 2 and the motor, effectively reducing the pump footprint increased by the use of the double-suction impeller 4, making the pump structure compact.

[0053] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A direct-connected horizontal cantilever double-suction pump, comprising Pump body (2), a pump cover (5) disposed on the pump body (2), and The electric motor (8) is characterized in that Also includes a double-suction impeller (4) disposed in the pump body (2), A suction port (21) is arranged at the end of the pump body (2) in a horizontal direction, wherein a flow dividing partition (24) is arranged in the suction port (21), and the flow dividing partition (24) divides the flow channel (23) of the suction port (21) into two flow dividing flow channels, a direct-connection shaft (81) connected to the motor (8), one end of the direct-connection shaft (81) being connected to the motor (8), and the other end of the direct-connection shaft (81) passing through the pump body (2) being connected to the double-suction impeller (4), a discharge port (22) disposed on the pump body (2) and perpendicular to the suction port; The inlet structures on both sides of the double-suction impeller (4) are identical and symmetrical. The pump cover (5) is composed of an annular hydraulic structure, the inner wall of which is annular. Sealing rings (3) are provided on both side inlets of the double-suction impeller (4), and the sealing rings (3) are connected to the pump body (2) by interference fit. It also includes a container-type mechanical seal (6) arranged on the pump body (2), and the rotating component of the container-type mechanical seal (6) is arranged on the direct-connection shaft (81).

2. The direct-connected horizontal cantilever double-suction pump according to claim 1, characterized in that: The direct-connection shaft (81) is formed by the main shaft of the electric motor (8).

3. The direct-connected horizontal cantilever double-suction pump according to claim 2, characterized in that: A water retaining ring (10) is provided at the connection between the direct-connection shaft (81) and the pump body (2).

4. The direct-connected horizontal cantilever double-suction pump according to claim 1, characterized in that: The discharge port (22) is provided with a sealing flushing pipe component (7).

5. The direct-connected horizontal cantilever double-suction pump according to claim 4, characterized in that: One end of the sealing flushing pipe component (7) is connected to the discharge port (22), and the other end is connected to the container-type mechanical seal (6).

6. The direct-connected horizontal cantilever double-suction pump according to claim 1, characterized in that: It also comprises a machine unit base (9), wherein the machine unit base (9) is used to support the motor (8) and the pump body (2).

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