CN111536050A

CN111536050A - Centrifugal pump with adjustable clearance between impeller and pump shell

Info

Publication number: CN111536050A
Application number: CN202010426013.0A
Authority: CN
Inventors: 张兰春; 章嘉晶
Original assignee: Jiangsu University of Technology
Current assignee: Jiangsu University of Technology
Priority date: 2020-05-19
Filing date: 2020-05-19
Publication date: 2020-08-14

Abstract

The invention belongs to the technical field of centrifugal pumps, and relates to a centrifugal pump with an adjustable gap between an impeller and a pump shell, which comprises a pump shell, the impeller arranged in the pump shell and a motor capable of driving the impeller to rotate, wherein an output shaft of the motor penetrates into the pump shell and is fixedly connected with the impeller, a stroke hole for an output shaft to move up and down is formed in the pump shell, the stroke hole is hermetically connected with the output shaft through a rubber sleeve, the gap between the impeller and the pump shell can be adjusted by the up-and-down movement of the output shaft in the stroke hole, the pump shell or the motor is connected with a driving mechanism, and the up-and-down movement of the pump shell or the motor. The centrifugal pump adjusts the flow of the centrifugal pump by adjusting the gap between the impeller and the pump shell, is convenient and quick, can greatly shorten the whole operation time, is beneficial to improving the operation efficiency of the whole system, is beneficial to vibration reduction and stability enhancement of the whole system, has great market value, and is worthy of wide popularization and application.

Description

Centrifugal pump with adjustable clearance between impeller and pump shell

Technical Field

The invention belongs to the technical field of centrifugal pumps, and particularly relates to a centrifugal pump with an adjustable gap between an impeller and a pump shell.

Background

The pump is an important energy conversion device and fluid conveying equipment, and the centrifugal pump is most widely applied to various pumps, and accounts for about 70% of the total amount of the pump equipment. The centrifugal pump is not only in the industrial and agricultural fields of petroleum, chemical industry, water conservancy, irrigation and the like, but also is a key component in the high-tech fields of nuclear power, aviation and the like. With social progress and development of science and technology, the reliability and the application range of the centrifugal pump are more and more emphasized. At present, the commonly used adjustment methods for the flow rate of the centrifugal pump include variable speed adjustment (changing the rotating speed of the water pump), variable diameter adjustment (cutting an impeller), variable angle adjustment (changing the installation angle of a blade), and the like, and the adjustment methods all need to disassemble the centrifugal pump and replace corresponding parts. The steps of disassembly, inspection and installation of the centrifugal pump are complex, and a great deal of time and resources are consumed in actual production application. Therefore, in order to solve this problem, the present application proposes a centrifugal pump capable of changing the clearance between the impeller and the pump casing.

The size of impeller and pump case clearance directly influences the efficiency of pump, and its main reason is: in the vicinity of the volute tongue, a thick layer of fluid is retained in the vicinity of the pump casing, on the side close to the outer diameter of the impeller, and this part of the fluid consumes work and causes loss. The larger the clearance, the larger the loss, thereby reducing the efficiency, and the reaction is that the flow is reduced in quantity, so that the effective power is reduced, and the pump flow can be changed by changing the clearance between the impeller and the pump shell.

Disclosure of Invention

The invention aims to solve the problem that the flow regulation mode of the existing centrifugal pump is complex, and the centrifugal pump with the adjustable gap between the impeller and the pump shell is designed.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a centrifugal pump with an adjustable gap between an impeller and a pump shell comprises the pump shell, the impeller arranged in the pump shell and a motor capable of driving the impeller to rotate, wherein an output shaft of the motor penetrates through the interior of the pump shell and is fixedly connected with the impeller, a stroke hole for the output shaft to move up and down is formed in the pump shell, the stroke hole is in sealing connection with the output shaft through a rubber sleeve, and the gap between the impeller and the pump shell can be adjusted through the up and down movement of the output shaft in the stroke hole.

Preferably, the pump shell or the motor is connected with a driving mechanism, and the driving mechanism can realize the up-and-down movement of the pump shell or the motor, so that the output shaft can relatively move up and down in the travel hole.

Preferably, the pump shell is fixed on the pump base through the pump support frame, a plurality of plunger type hydraulic cylinders are arranged below the pump base, and the pump shell can be driven to move up and down through the plunger type hydraulic cylinders.

Preferably, the plunger type hydraulic cylinders are four and are respectively arranged at four corners below the pump base through rubber gaskets.

Preferably, one side of the pump shell, which is far away from the motor, is provided with a water inlet flange, and a water outlet flange is arranged above the pump shell.

Preferably, the impeller is a semi-open impeller and comprises a cover plate and a plurality of blades arranged on the cover plate, and a mounting hole matched with the output shaft is formed in the middle of the cover plate.

Preferably, a sealing end cover is arranged on one side of the pump shell close to the motor, stroke holes are formed in the pump shell and the sealing end cover, and the up-and-down relative movement stroke of the output shaft in the stroke holes is 10 mm.

Preferably, the rubber sleeve is sleeved on the output shaft, the cross section of the rubber sleeve is of a trapezoidal structure, one end with a large diameter is in sealing connection with the sealing end cover, and the other end with a small diameter is in sealing connection with the output shaft.

Preferably, the motor is fixed on the motor base through a motor support frame.

After the technical scheme is adopted, the centrifugal pump with the adjustable gap between the impeller and the pump shell has the following beneficial effects:

(1) adjusting the flow: the invention changes the thickness of the fluid which is near the volute tongue and clings to the outer diameter side of the impeller and is retained in the pump shell by changing the clearance between the impeller and the pump shell, thereby changing the efficiency and changing the flow.

(2) The efficiency is improved: in the long-term operation of the centrifugal pump, under the abrasion of particles, the clearance between the blade and the inner side wall of the pump shell is enlarged, and the efficiency is reduced; the invention can offset the movement amount caused by abrasion by adjusting the clearance between the impeller and the volute, reduce the loss and improve the effective power.

(3) Vibration reduction and stability augmentation: when the centrifugal pump conveys media with larger particles, the abrasion of the media enlarges the gap between the blade and the inner side wall of the pump shell, and the stability of the liquid flow state is damaged, so that the pump generates vibration; the invention counteracts the movement amount caused by abrasion by adjusting the gap between the impeller and the pump shell, and reduces the vibration; meanwhile, the rubber gasket arranged at the bottom of the pump also has the function of buffering and damping, and the rubber gasket is also connected with the plunger type hydraulic cylinder, so that the original natural frequency is changed and a certain damping effect is achieved.

Drawings

FIG. 1 is a schematic structural view of a centrifugal pump with adjustable clearance between an impeller and a pump casing according to the present invention;

FIG. 2 is a perspective view of a pump housing portion of the present invention;

FIG. 3 is a front elevational view of a pump housing portion of the present invention;

FIG. 4 is a schematic structural view of a pump casing close to a motor and a seal cover in the present invention;

FIG. 5 is a schematic structural view of a hermetic end cap according to the present invention;

fig. 6 and 7 are comparative views showing the positions of the impellers inside the pump casing after the clearance is changed.

Wherein: the pump comprises a pump shell 1, an impeller 2, a motor 3, an output shaft 4, a stroke hole 5, a rubber sleeve 6, a pump support frame 7, a pump base 8, a plunger type hydraulic cylinder 9, a rubber gasket 10, a water inlet flange 11, a water outlet flange 12, a cover plate 13, blades 14, a mounting hole 15, a sealing end cover 16, a motor support frame 17 and a motor base 18.

Detailed Description

The present invention now will be described more fully hereinafter with reference to the accompanying drawings and detailed description, in which it is to be understood that the embodiments described are merely illustrative of some, but not all embodiments of the invention. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The invention relates to a centrifugal pump with adjustable clearance between an impeller and a pump shell, which comprises a pump shell 1, an impeller 2 arranged in the pump shell 1 and a motor 3 capable of driving the impeller 2 to rotate, wherein a water inlet flange 11 is arranged on one side of the pump shell 1 far away from the motor 3, a water outlet flange 12 is arranged above the pump shell 1, the impeller 2 is a semi-open impeller and comprises a cover plate 13 and a plurality of blades 14 arranged on the cover plate 13, a mounting hole 15 matched with an output shaft 4 is formed in the middle of the cover plate 13, the output shaft 4 of the motor 3 penetrates into the pump shell 1 and is fixedly connected with the impeller 2 through the mounting hole 15, a stroke hole 5 for the output shaft 4 to move up and down is formed in the pump shell 1, specifically, a sealing end cover 16 is arranged on one side of the pump shell 1 near the motor 3, stroke holes 5 are formed in the pump shell 1 and the sealing end cover 16, the up-down relative movement stroke of the output shaft 4 in, the stroke hole 5 and the output shaft 4 are connected through a rubber sleeve 6 in a sealing mode, specifically, the rubber sleeve 6 is sleeved on the output shaft 4, the cross section of the rubber sleeve 6 is of a trapezoidal structure, one end with the large diameter is connected with the sealing end cover 16 in a sealing mode, one end with the small diameter is connected with the output shaft 4 in a sealing mode, a through hole with the diameter identical to that of the output shaft 4 is formed in one end with the small diameter, the output shaft 4 can be arranged in the through hole in a rotating and sealing mode, and the adjustment of the gap between the impeller and the pump shell can be achieved through the up-and-.

Further, the pump case 1 or the motor 3 is connected with a driving mechanism, the driving mechanism can realize the up-and-down movement of the pump case 1 or the motor 3, so that the output shaft 4 can relatively move up and down in the stroke hole 5, specifically, the pump case 1 is fixed on the pump base 8 through the pump support frame 7, the motor 3 is fixed on the motor base 18 through the motor support frame 17, a plurality of plunger type hydraulic cylinders 9 are arranged below the pump base 8, the pump case 1 can be driven to move up and down through the plunger type hydraulic cylinders 9, specifically, four plunger type hydraulic cylinders 9 are arranged and are respectively installed on four corners below the pump base 8 through rubber gaskets 10, and the plunger diameter of the plunger type hydraulic cylinders 9 is smaller than the diameter of the rubber gaskets 10.

When the centrifugal pump with the adjustable gap between the impeller and the pump shell works, in an initial state, the four plunger type hydraulic cylinders 9 extend to a certain height to enable the pump base 8 and the motor base 18 to be positioned on the same horizontal plane, when the flow of the centrifugal pump needs to be improved or the centrifugal pump is detected to be worn during the transportation of large-particle media, the gap between the blade 14 and the inner side wall of a pressure water chamber (the pump shell 1 in the invention) is increased, so that the efficiency is reduced, under the condition that the pump vibrates, the oil pressure of the four plunger type hydraulic cylinders 9 is reduced, under the self-weight and the weight of the centrifugal pump, the plungers of the four plunger type hydraulic cylinders 9 slowly descend for a certain distance, so that the pump base 8 is driven to descend, namely the pump shell 1 is driven to be descended, the rubber sleeve 6 arranged behind the sealing end cover 16 generates certain deformation along with the movement of, the output shaft 4 generates ascending motion relative to the pump shell 1 through the stroke holes 5 arranged on the pump shell 1 and the sealing end cover 16, the impeller 2 also generates ascending motion relative to the pump shell 1, and the gap between the impeller 1 and the pump shell 1 is reduced, so that the purposes of improving the flow rate of the centrifugal pump, increasing the efficiency and reducing the vibration are achieved; when the flow of the centrifugal pump needs to be properly reduced, the oil pressure of the four plunger type hydraulic cylinders 9 is increased, the plungers of the four plunger type hydraulic cylinders 9 rise for a certain distance, so that the pump base 8 is driven to rise, namely, the pump shell 1 is driven to rise, the rubber sleeve 6 arranged behind the sealing end cover 16 generates certain deformation along with the movement of the pump shell 1, the output shaft 4 is fixed, the impeller 2 connected with the output shaft 4 is also fixed, the output shaft 4 generates descending movement relative to the pump shell 1 through the stroke holes 5 arranged on the pump shell 1 and the sealing end cover 16, the impeller 2 also generates descending movement relative to the pump shell 1, and the gap between the impeller 2 and the pump shell 1 is increased, so that the aim of reducing the flow of the centrifugal pump is achieved.

In conclusion, the centrifugal pump with the adjustable gap between the impeller and the pump shell, provided by the invention, has the advantages of simple structure and strong practicability, the flow of the centrifugal pump is adjusted by adjusting the gap between the impeller and the pump shell, the centrifugal pump is convenient and quick, the whole operation time can be greatly shortened, the operation efficiency of the whole system can be improved, the vibration reduction and the stability increase of the whole system can be facilitated, the market value is high, and the centrifugal pump is worthy of wide popularization and application.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. The utility model provides an impeller and pump case clearance adjustable centrifugal pump, includes pump case (1), sets up impeller (2) in pump case (1) to and can drive impeller (2) pivoted motor (3), its characterized in that: an output shaft (4) of the motor (3) penetrates into the pump shell (1) and is fixedly connected with the impeller (2), a stroke hole (5) for the output shaft (4) to move up and down is formed in the pump shell (1), the stroke hole (5) is connected with the output shaft (4) in a sealing mode through a rubber sleeve (6), and the adjustment of the gap between the impeller and the pump shell can be achieved through the up-and-down movement of the output shaft (4) in the stroke hole (5).

2. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: the pump shell (1) or the motor (3) is connected with a driving mechanism, the pump shell (1) or the motor (3) can move up and down through the driving mechanism, and therefore the output shaft (4) can move up and down relatively in the stroke hole (5).

3. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: the pump shell (1) is fixed on a pump base (8) through a pump support frame (7), a plurality of plunger type hydraulic cylinders (9) are arranged below the pump base (8), and the pump shell (1) can be driven to move up and down through the plunger type hydraulic cylinders (9).

4. A centrifugal pump according to claim 3, wherein the clearance between the impeller and the pump casing is adjustable by: the plunger type hydraulic cylinders (9) are four and are respectively arranged at four corners below the pump base (8) through rubber gaskets (10).

5. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: one side of the pump shell (1) far away from the motor (3) is provided with a water inlet flange (11), and a water outlet flange (12) is arranged above the pump shell (1).

6. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: the impeller (2) is a semi-open impeller and comprises a cover plate (13) and a plurality of blades (14) arranged on the cover plate (13), and a mounting hole (15) matched with the output shaft (4) is formed in the middle of the cover plate (13).

7. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: the motor is characterized in that a sealing end cover (16) is arranged on one side, close to the motor (3), of the pump shell (1), stroke holes (5) are formed in the pump shell (1) and the sealing end cover (16), and the up-down relative movement stroke of the output shaft (4) in the stroke holes (5) is 10 mm.

8. A centrifugal pump according to claim 7, wherein the clearance between the impeller and the pump casing is adjustable by: the rubber sleeve (6) is sleeved on the output shaft (4), the cross section of the rubber sleeve (6) is of a trapezoidal structure, one end with a large diameter is connected with the sealing end cover (16) in a sealing mode, and the other end with a small diameter is connected with the output shaft (4) in a sealing mode.

9. A centrifugal pump according to claim 1, wherein the clearance between the impeller and the pump casing is adjustable by: the motor (3) is fixed on the motor base (18) through a motor support frame (17).