CN205401257U - Low noise multistage centrifugal pump - Google Patents

Abstract

The utility model discloses a liquid-cooled low-noise multistage centrifugal pump, which comprises a pump body, a liquid-cooled motor, a pump shaft sleeved with a shaft sleeve and a spacer ring, a sliding bearing sleeved outside the shaft sleeve, and the pump shaft. The connected coupling, the motor that drives the pump shaft to rotate through the coupling, the impeller inserted on the pump shaft, and a plurality of guide vanes that are fastened by steel belts and matched in series with each other. The liquid-cooled low-noise multi-stage centrifugal pump of the utility model adopts a liquid-cooled motor to eliminate the noise caused by the traditional motor using a cooling fan, and at the same time, the motor is double-enclosed by the inner casing and the outer casing of the motor to hinder the transmission of motor noise , thereby reducing the noise of the centrifugal pump; in addition, since the cooling liquid cools the stator and bearings of the motor at the same time, the heat generated by the motor is taken away in time, the temperature of the motor is reduced, and the efficiency of the motor is improved, thereby improving the performance of the multistage centrifugal pump. s efficiency.

Description

Low noise multistage centrifugal pump

technical field

The utility model relates to the fields of industrial liquid transportation and urban water supply and drainage, in particular to a low-noise stainless steel multistage centrifugal pump driven by a liquid-cooled motor.

Background technique

Multi-stage centrifugal pumps are used in the transportation of industrial liquids and urban water supply and drainage, pressurized water supply for high-rise buildings, garden sprinkler irrigation, fire pressurization, long-distance water supply, heating, bathrooms, etc. delivery etc.

At present, most of the motors used in multistage centrifugal pumps are standard industrial motors. It is difficult for standard industrial motors to meet customer requirements for applications with high noise requirements, such as residences, business offices, hotels, etc. There are two main ways to reduce noise: one is to reduce the vibration power of the noise source, and the other is to hinder or cut off its transmission path. Reducing the vibration power of noise sources has always been the pursuit of designers, but it is difficult and costly. Obstructing or cutting off the noise transmission path can also effectively reduce the noise level, but requires a large space and is expensive.

The liquid-cooled multi-stage centrifugal pump of the utility model adopts a liquid-cooled motor and removes a cooling fan on the traditional motor, thus eliminating a noise source. At the same time, the motor is double-enclosed by the inner shell and the outer shell of the motor, which hinders the noise of the motor. The transmission path reduces the noise of the motor, thereby reducing the noise of the centrifugal pump; on the other hand, the stator and the support bearing of the motor are cooled by the liquid at the same time, and the heat generated by the motor is taken away in time, which reduces the temperature of the motor and improves the performance of the motor. The efficiency, thereby improving the efficiency of the multistage centrifugal pump.

Utility model content

In order to solve the above technical problems, the utility model provides a solution for reducing the noise of a multistage centrifugal pump.

In order to achieve the above object, the technical scheme of the utility model is as follows:

A low-noise multi-stage centrifugal pump comprising:

a pump body, located at the bottom of the centrifugal pump, the pump body includes a liquid suction port and a discharge port;

The pump shaft is axially accommodated in the pump body, and the pump shaft is sleeved with a shaft sleeve and an impeller spacer ring;

a sliding bearing, sleeved on the outside of the bushing, and slidingly supporting the pump shaft;

The impeller is inserted on the pump shaft and axially positioned by the impeller spacer ring, and the pump shaft drives the impeller to rotate, thereby pressurizing the fluid entering from the suction port of the pump body;

The guide vane is installed outside the shaft sleeve. The liquid pressurized by the impeller is collected by the guide vane at the first stage and the flow rate is reduced, and then enters the next stage of the impeller to continue to pressurize until the liquid is discharged from the discharge port And sent to the water supply system;

A liquid-cooled motor, which is axially installed on the upper end of the pump body through a motor bracket, and the motor bracket and the pump body are locked by tension bolts; the motor bracket has a bracket inner shell and a bracket outer shell, and the bracket inner shell is connected to the A liquid introduction hole and a liquid return hole communicating with the pump body chamber are formed between the bracket shells; the shell of the liquid-cooled motor is composed of a motor inner shell containing a motor stator and a motor shell, and the inner shell of the motor and the electrode shell A motor liquid return pipe is formed between them for the circulation of the motor coolant; the chamber for accommodating the impeller and the guide vane has an outer cylinder and an inner cylinder, and a passage connecting the liquid return hole is formed between the outer cylinder and the inner cylinder. A liquid return pipe, the outlet of the liquid return pipe is connected to the discharge port of the pump body;

The motor shaft is axially accommodated in the middle of the motor inner shell of the liquid-cooled motor, and is driven to rotate by the liquid-cooled motor;

rolling bearings rolling to support the motor shaft;

A shaft coupling is used to connect the motor shaft and the pump shaft, and the liquid-cooled motor drives the pump shaft to rotate through the motor shaft and the coupling;

Mechanical seals are used where the pump shaft passes through the two sides of the motor bracket, so as to block the fluid in the pump body from entering the motor bracket.

Wherein, the rolling bearing includes a front rolling bearing and a rear rolling bearing, which are respectively used to roll and support the front end and the rear end of the motor shaft, the front rolling bearing is arranged on the top of the motor support, and the motor shaft passes through the front end The rolling bearing extends into the motor bracket and is connected with the pump shaft through the shaft coupling.

Wherein, the rolling bearing is an angular contact deep groove ball bearing, so that it has the bearing capacity of axial load.

Further, the motor bracket is also provided with a sealing plate sleeved on the motor shaft, and the sealing plate forms a cooling liquid circulation channel between the sealing ring and the motor bracket to take away the front end The heat generated between the rolling bearing and the motor bracket and the motor shaft; the inlet and outlet of the cooling liquid channel between the sealing plate, the sealing ring and the motor bracket are respectively connected to the outlet of the liquid introduction hole and the inlet of the liquid return hole.

Wherein, the impeller of the first stage is axially positioned by the shaft nut, the impeller of the first stage and the second stage are axially positioned by the bushing, and the impellers of the other stages are axially positioned by the impeller spacer ring. Further, there are multiple protrusions on the inner ring of the impeller radially fixed on multiple grooves on the outer wall of the pump shaft.

Wherein, one end of the guide vane in the first stage is inserted into the shaft sleeve, and the other end of the guide vane in the first stage is positioned with the rest of the guide vanes through cascading cooperation of steel belts.

Wherein, the shaft sleeve and the guide vane are assembled together through an interference fit, and the sliding bearing and the shaft sleeve are fitted with a clearance.

The low-noise multi-stage centrifugal pump of the utility model adopts a liquid-cooled motor, which removes the cooling fan on the traditional motor and eliminates a noise source. At the same time, the motor is double-enclosed by the motor inner shell and the motor shell, which hinders the transmission of noise and reduces the noise. The noise of the motor, thereby reducing the noise of the centrifugal pump; on the other hand, during the working process of the multi-stage centrifugal pump, the stator and the supporting bearing of the motor are cooled through the liquid circulation at the same time, and the heat generated by the motor is taken away in time, reducing the motor. The temperature improves the efficiency of the motor, thereby improving the efficiency of the multistage centrifugal pump.

Description of drawings

Fig. 1 is a schematic structural view of a low-noise multi-stage centrifugal pump disclosed in an embodiment of the present invention.

The numbers in the figure indicate:

1. Steel belt 2. Impeller 3. Sliding bearing

4. Shaft sleeve 5. Guide vane 6. Tension bolt

7. Mechanical seal 8. Liquid introduction hole 9. Front end rolling bearing

10. Motor housing 11. Liquid-cooled motor 12. Rear end rolling bearing

13. Pump body 14. Outer cylinder 15. Liquid return pipe

16. Impeller spacer ring 17. Pump shaft 18. Liquid return hole

19. Coupling 20. Motor bracket 21. Sealing ring

22. Sealing plate 23. Motor inner shell 24. Motor return pipe

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention.

Figure 1 is a schematic diagram of a low-noise multi-stage centrifugal pump of the present invention taking two stages as an example. As shown in the figure, the low-noise multi-stage centrifugal pump of the present invention specifically includes: steel belt 1, impeller 2, sliding bearing 3, shaft Sleeve 4, guide vane 5, tension bolt 6, mechanical seal 7, liquid introduction hole 8, front rolling bearing 9, motor casing 10, liquid-cooled motor 11, rear rolling bearing 12, pump body 13, outer cylinder 14, liquid return pipe 15. Impeller spacing ring 16, pump shaft 17, liquid return hole 18, coupling 19, bracket 20, sealing ring 21, sealing plate 22, motor inner shell 23, motor return pipe 24.

The pump shaft 17 is accommodated in the impeller 2 and the guide vane 5 , the impeller 2 is plugged on the pump shaft 17 , and the pump shaft 17 is sleeved with the shaft sleeve 4 and the impeller spacer ring 16 . The sliding bearing 3 is sleeved on the inner side of the shaft sleeve 4 to slide and support the pump shaft 17, and the sliding bearing 3 and the shaft sleeve 4 are clearance fit. The shaft sleeve 4 is assembled on the guide vane 5 by interference fit. The machining accuracy of the shaft sleeve 4 is relatively high. The machining requirements of the impeller spacer ring 16 are relatively much lower, and its main function is the axial positioning between the impellers 2 .

The pump shaft 17 is supported by the sliding bearing 3 through the shaft sleeve 4 . The motor shaft of the liquid-cooled motor 11 is supported by the front-end rolling bearing 9 and the rear-end rolling bearing 12. The front-end rolling bearing 9 is generally an angular contact deep groove ball bearing with axial load bearing capacity, while the rear-end rolling bearing 12 adopts a common deep-groove ball bearing, and sometimes the rear-end rolling bearing 12 Angular contact deep groove ball bearings are used. The pump shaft 17 is connected to the motor shaft through a coupling 19, the external liquid-cooled motor 11 drives the pump shaft 17 to rotate through the coupling 19, and the pump shaft 17 drives the impeller 2 to rotate, thereby pressurizing the fluid sucked from the pump body 13. The guide vanes 5 are matched with each other in series and fastened together by the steel belt 1 , the pressurized liquid passing through the impeller 2 is collected by the guide vanes 5 and the flow velocity is reduced, and discharged through the outlet of the pump body 13 .

The first-stage impeller 2 is axially positioned by the shaft nut, the first-stage and second-stage impellers are axially positioned by the bushing 4 , and the rest of the impellers 2 are axially positioned by the impeller spacer ring 16 . There are a plurality of projections on the inner ring of the impeller 2 and are radially fixed on a plurality of grooves of the pump shaft 17 .

The function of the guide vane 5 is to collect the liquid thrown out by the impeller 2, reduce the flow velocity of the liquid, convert part of the velocity energy into pressure energy, and then evenly introduce it into the next stage or discharge the incoming fluid through the outlet of the pump body 13 pipe network system. The guide vane 5 makes the liquid flow in the continuous flow channel, which is not easy to form dead angle and sudden diffusion, the change of fluid velocity is relatively uniform, and the hydraulic performance is good.

One end of some guide vanes 5 is plugged on the shaft sleeve 4 , and the other end is positioned through the cascade fit between the guide vanes 5 , for example, the first stage guide vanes 5 . The shaft sleeve 4 and the guide vane 5 are assembled together through an interference fit, and the sliding bearing 3 and the shaft sleeve 4 are clearance fit. Some guide vanes 5 do not need to be assembled with shaft sleeves 5 , and are positioned through cascading cooperation with other guide vanes 5 , that is, the other ends of guide vanes 5 of each level are fixed by steel belts 1 in cascade.

According to different impeller diameters and different stages, the multi-stage centrifugal pump can be equipped with multiple sliding bearings 3, and by adjusting the number of sliding bearings 3, the safe and stable operation of the multi-stage centrifugal pump can be ensured.

A liquid introduction hole 8 and a liquid return hole 18 are opened on the motor bracket 20 as circulation channels for cooling the motor liquid. The liquid is introduced into the closed cavity between the motor inner shell 23 and the motor shell 10 from the high-pressure chamber of the centrifugal pump through the liquid introduction hole 8 on the motor bracket 20, and the cooling liquid passes through the motor bracket 20 after passing through the motor liquid return pipe 24. The liquid return hole 18 communicates with the low-pressure cavity of the multi-stage pump through the liquid return pipe 15 to form a circulation system. The liquid for cooling the motor is separated from the outside world by the sealing plate 22 through the sealing ring 21, and part of the cooling liquid flows through the liquid introduction hole 8 into the cavity formed by the motor bracket 20, the sealing plate 22 and the sealing ring 21, and then flows into the liquid return hole 18 Internal cooling is done inside. During the working process of the multi-stage centrifugal pump, the circulating liquid promptly takes away the heat generated by the stator of the motor and the heat generated by the mechanical friction of the supporting bearing during the working process, so that the temperature of the motor and the supporting bearing is always kept at a temperature that is relatively low compared to the air-cooled motor. Low temperature, which improves the efficiency of the motor, thereby improving the efficiency of the low-noise multi-stage pump.

The two sides where the pump shaft 17 passes through the motor bracket 20 adopt mechanical seals 7 to block the fluid in the pump body 13 from entering the inside of the motor bracket 20 .

The pump shaft 17 of the low-noise multi-stage centrifugal pump of the present invention is directly driven by the liquid-cooled motor 11 through the coupling 19, and the pump shaft 17 drives the impeller 2 to pump the liquid to a specified lift. The low-noise multi-stage centrifugal pump sucks the liquid into the low-noise multi-stage centrifugal pump through the suction port of the pump body 13 and through the impeller 2. After the liquid is pressurized by the impeller 2, it enters the lower impeller 2 through the guide vane 5 to continue to pressurize, and then passes through the lower guide vane. 5 enters the next stage impeller to pressurize until it passes through the final stage impeller 2 and then discharges through the final guide vane 5 after the pressurization process is completed. Finally, the low-noise multi-stage centrifugal pump passes the high-pressure liquid through the gap between the guide vane 5 and the outer cylinder 14 The flow channel of the pump body 13 is sent into the pipeline system from the discharge port.

According to the requirements of the conveying medium, the low-noise multi-stage centrifugal pump of the present invention can use corresponding materials, such as rust-resistant and corrosion-resistant materials such as stainless steel and titanium alloy.

Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. a low noise centrifugal multistage pump multiple centrifugal pump, it is characterised in that including:

The pump housing, is positioned at bottom described centrifugal pump, and the described pump housing includes fluid intake and outlet；

Pump shaft, is axially contained in the described pump housing, and described pump shaft is socketed with axle sleeve and wheel space ring；

Sliding bearing, is socketed in outside described axle sleeve, pump shaft described in sliding support；

Impeller, is plugged on described pump shaft and by described wheel space annulate shaft to location, and described pump shaft drives described wheel rotation, thus the fluid pressurization that will enter from described pump housing suction inlet；

Stator, is arranged on outside described axle sleeve, and flow velocity is collected and reduced to the liquid stator described in chopped-off head pressurizeed by described impeller, enters impeller described in next stage and continues pressurization until liquid being discharged from described outlet and sending into water supply system；

Fluid-cooled electrical machine, it is axially mounted to described pump housing upper end by electric machine support, and described electric machine support and the pump housing are locked by turnbuckle；Described electric machine support has support inner shell and rack shell, forms the guiding fluid hole and the hole for back flow that connect described pump housing chamber between described support inner shell and rack shell；The housing of described fluid-cooled electrical machine is made up of the motor inner shell comprising motor stator and motor housing, forms the circulation for motor coolant of the motor liquid back pipe between described motor inner shell and electrode shell；Chamber for housing described impeller and stator has urceolus and inner core, forms the liquid back pipe connecting described hole for back flow between described urceolus and inner core, the outlet of the outlet of the described liquid back pipe extremely described pump housing；

Motor shaft, is axially contained in the middle of the described motor inner shell of described fluid-cooled electrical machine, described fluid-cooled electrical machine drive and rotate；

Rolling bearing, motor shaft described in rolling support；

Shaft coupling, is used for coupling described motor shaft and pump shaft, and described fluid-cooled electrical machine drives described pump shaft to rotate by described motor shaft and shaft coupling；

Described pump shaft adopts mechanical seal through two side positions of described electric machine support, to cut off the fluid described electric machine support of entrance in the described pump housing.

2. low noise centrifugal multistage pump multiple centrifugal pump according to claim 1, it is characterized in that, described rolling bearing includes front end rolling bearing and rear end rolling bearing, it is respectively used to front end and the rear end of motor shaft described in rolling support, described front end rolling bearing is arranged on the top of described electric machine support, and described motor shaft is stretched in described electric machine support after the rolling bearing of described front end and is connected with described pump shaft by described shaft coupling.

3. low noise centrifugal multistage pump multiple centrifugal pump according to claim 2, it is characterised in that described rolling bearing is angular contact deep groove ball bearing, to make it have the bearing capacity of axial load.

4. low noise centrifugal multistage pump multiple centrifugal pump according to claim 3, it is characterized in that, being additionally provided with the sealing plate being socketed on described motor shaft in described electric machine support, described sealing plate is by forming coolant circulation passage for taking away the heat produced between described front end rolling bearing and electric machine support and motor shaft between sealing ring and described electric machine support；Described sealing plate, the entrance of cooling passage between sealing ring and electric machine support is respectively communicated to the outlet of described guiding fluid hole and the entrance of hole for back flow with outlet.

5. low noise centrifugal multistage pump multiple centrifugal pump according to claim 1, it is characterized in that, impeller described in chopped-off head is axially positioned by axis head nut, is axially positioned by axle sleeve between chopped-off head and second level impeller, by described wheel space annulate shaft to location between all the other impellers at different levels.

6. low noise centrifugal multistage pump multiple centrifugal pump according to claim 5, it is characterised in that have multiple projection radially fixed on multiple grooves of pump shaft outer wall on the inner ring of described impeller.

7. low noise centrifugal multistage pump multiple centrifugal pump according to claim 1, it is characterised in that one end of stator described in chopped-off head is plugged on described axle sleeve, coordinates location by steel band tandem between the other end of stator described in chopped-off head with all the other stators.

8. low noise centrifugal multistage pump multiple centrifugal pump according to claim 1, it is characterised in that between described axle sleeve and stator, logical interference fit is assembled together, and is matched in clearance between described sliding bearing and axle sleeve.