Sealing structure and centrifugal feeding pump

Abstract

The present application discloses a sealing structure and a centrifugal feeding pump. The sealing structure comprises a flange base, a stationary ring assembly, and a rotating ring assembly, the flange base is provided with a mounting passage, and the stationary ring assembly is mounted in the mounting passage; the rotating ring assembly is mounted on the outer periphery of a rotating shaft and located in the mounting passage; the rotating ring assembly abuts against the stationary ring assembly in the axial direction; a gap is formed between the end of the rotating ring assembly facing a pump cavity and the side wall of the mounting passage; a helical protrusion located within the gap is provided on the outer periphery of the rotating ring assembly; and a conveying direction of the helical protrusion is oriented towards the pump cavity, so that when the rotating shaft rotates, the helical protrusion pushes a medium away from a position where the rotating ring assembly abuts against the stationary ring assembly. In the present application, when the helical protrusion rotates, a force directed toward the pump cavity can be generated to prevent medium particles from entering the gap, thereby effectively protecting the operating environment of a friction pair and extending the service life.

Description

Sealing structure and centrifugal feed pump TECHNICAL FIELD

[0001] The present application relates to the technical field of feed pumps, in particular to a sealing structure and a centrifugal feed pump. BACKGROUND

[0002] The high-temperature and high-pressure slurry preheater is a device for storing and heating high-pressure slurry. The slurry is a three-phase mixed slurry mainly composed of solid, liquid and gas. The solid content is generally 35% to 40%, and the rest is steam and acid-containing solution with a pH of 2 to 4. The preheater is usually a sealed cylindrical tank with pressure inside. As the medium temperature rises from 105°C to 165°C, the pressure in the tank rises from 0.8 MPa to 2.2 MPa. Generally, a centrifugal feed pump is used to deliver slurry to the high-temperature and high-pressure slurry preheater.

[0003] Chinese patent CN110131172A discloses a centrifugal pump with enhanced sealing, which comprises a pump body and a rotating shaft. The pump body has a suction inlet, a working cavity and a discharge outlet. A rotating seal is established between the rotating shaft and the pump body by providing a water seal assembly. The water seal assembly includes a dynamic ring, a static ring, a spring and an elastic sleeve. A pressurizing disc is slidably arranged in the pump body, and the end of the spring and the elastic sleeve away from the dynamic ring is located on the pressurizing disc. A sandwich plate is arranged in the pump body, and a pressurizing cavity is formed between the sandwich plate and the outer wall of the pump body. The position of the pressurizing cavity connected to the working cavity is close to the discharge outlet.

[0004] In the above prior art, the side surfaces of the dynamic ring and the static ring are friction surfaces, and the two friction surfaces abut against each other to achieve sealing. However, when delivering slurry, the medium containing solid particles in the pump cavity will flow towards the sealing friction surface, and the solid particles will cause wear to the friction surface, affecting the service life.

[0005] SUMMARY

[0006] The present application aims to overcome the above technical deficiencies and provide a sealing structure and a centrifugal feed pump to solve the technical problem that in the prior art, the medium containing solid particles in the pump cavity will flow towards the sealing friction surface, and the solid particles will cause wear to the friction surface, affecting the service life.

[0007] To achieve the above technical purpose, the present application adopts the following technical scheme:

[0008] The present application provides a sealing structure, which comprises:

[0009] A flange seat is provided with a mounting channel, and the flange seat is used to be sleeved on the outer periphery of the rotating shaft and mounted on the pump body.

[0010] A static ring assembly is mounted in the mounting channel; and

[0011] The dynamic ring assembly is mounted on the outer periphery of the rotating shaft and located in the mounting channel, and abuts with the static ring assembly in the axial direction. A gap is formed between one end of the dynamic ring assembly towards the pump cavity and the side wall of the mounting channel. The outer periphery of the dynamic ring assembly is provided with a spiral protrusion located in the gap. The conveying direction of the spiral protrusion is towards the pump cavity, so that the medium is pushed away from the abutting position of the dynamic ring assembly and the static ring assembly by the spiral protrusion when the rotating shaft rotates.

[0012] In some embodiments, the gap ranges from 0.2 mm to 0.3 mm.

[0013] In some embodiments, the spiral protrusion is an equidistant spiral protrusion.

[0014] In some embodiments, the dynamic ring assembly includes a dynamic ring seat and two dynamic rings. The dynamic ring seat is sleeved on the outer periphery of the rotating shaft. The spiral protrusion is arranged on the outer periphery of one end of the dynamic ring seat towards the pump cavity. The two dynamic rings are mounted on the outer periphery of the dynamic ring seat in an axial direction and are in sealing cooperation with the dynamic ring seat.

[0015] In some embodiments, the sealing structure further includes a shaft sleeve arranged on the outer periphery of the rotating shaft. The dynamic ring seat is sleeved on the outer periphery of the shaft sleeve and is in sealing cooperation with the shaft sleeve.

[0016] In some embodiments, the dynamic ring seat includes a first section and a second section connected in sequence in the axial direction. The two dynamic rings are mounted on both ends of the first section. The outer diameter of the second section is larger than that of the first section. The gap is formed between the second section and the side wall of the mounting channel. The spiral protrusion is located on the second section.

[0017] In some embodiments, the static ring assembly includes two static rings. The two static rings are arranged in an axial direction and located between the two dynamic rings. The static rings are in sealing cooperation with the side wall of the mounting channel. The two static rings abut with the two dynamic rings one by one.

[0018] In some embodiments, a sealing cavity is formed between the flange seat, the static ring assembly and the dynamic ring assembly. The sealing cavity is filled with an isolation liquid.

[0019] In some embodiments, the flange seat is further provided with an inlet communicating with the sealing cavity.

[0020] The sealing structure further includes a liquid supplement station communicating with the inlet, for conveying the isolation liquid into the sealing cavity.

[0021] In addition, the application also provides a centrifugal feed pump including the sealing structure.

[0022] Compared with the prior art, the sealing structure provided by the application has the flange seat installed on the pump body, the installation channel communicating with the pump cavity is arranged on the flange seat, one end of the rotating shaft extends into the pump cavity from the installation channel and is connected with the impeller, the static ring assembly is installed in the installation channel and annularly arranged outside the rotating shaft, the static ring assembly is fixedly connected with the flange seat, the dynamic ring assembly is fixedly installed outside the rotating shaft and located in the installation channel, and the static ring assembly and the dynamic ring assembly are sequentially arranged in the axial direction, the static ring assembly and the dynamic ring assembly abut against each other to form a seal, and the outer periphery of one end of the dynamic ring assembly towards the pump cavity is provided with a spiral protrusion, the static ring assembly and the spiral protrusion are arranged in the direction towards the pump cavity, when the rotating shaft rotates, the dynamic ring assembly and the spiral protrusion can be driven to rotate, so that the medium in the gap can be transported into the pump cavity, that is, when the spiral protrusion rotates, a force towards the pump cavity is formed to hinder the medium particles from entering the gap, so that the running environment of the friction pair between the dynamic ring assembly and the static ring assembly is effectively protected, and the service life is improved.

[0023] The above description is only a summary of the technical scheme of the application, in order to more clearly understand the technical means of the application, and can be implemented according to the content of the description, and the preferred embodiments of the application are described in detail below. The specific embodiments of the application are described in detail below. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a structural schematic view of an embodiment of the centrifugal feeding pump provided by the application;

[0025] Fig. 2 is a structural schematic view of an embodiment of the sealing structure provided by the application;

[0026] Fig. 3 is a partial sectional view of the sealing structure in Fig. 2;

[0027] Fig. 4 is a perspective view of the dynamic ring seat in Fig. 2.

[0028] EXPLANATION OF REFERENCE NUMERALS:

[0029] 100-sealing structure, 1-flange seat, 11-installation channel, 12-gap, 13-inlet, 2-static ring, 3-dynamic ring seat, 31-spiral protrusion, 4-dynamic ring, 5-liquid supplement station, 6-shaft sleeve, 7-holding ring, 200-centrifugal feeding pump, 210-motor assembly, 220-rotating shaft, 230-pump body, 240-impeller. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the application more clear and obvious, the application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and not to limit the application.

[0031] In order to solve the technical problem that the solid particles in the medium in the pump cavity flow to the sealing friction surface, the solid particles cause wear to the friction surface, and affect the service life in the prior art, the application provides a sealing structure which can transport the medium in the gap to the pump cavity, that is, when the spiral protrusion rotates, a force is formed to prevent the medium particles from entering the gap in the direction of the pump cavity, thereby effectively protecting the running environment of the friction pair between the rotating ring assembly and the static ring assembly, and improving the service life.

[0032] Please refer to FIG. 1, the application provides a centrifugal feed pump 200 which comprises the sealing structure 100, a motor assembly 210, a rotating shaft 220, a pump body 230, and an impeller 240. The sealing structure 100 comprises a flange seat 1, a static ring assembly, and a rotating ring assembly. The flange seat 1 is provided with a mounting channel 11. The pump body 230 is formed with a pump cavity. The pump body 230 is further provided with a through hole which communicates with the pump cavity. The impeller 240 is rotatably installed in the pump cavity. The flange seat 1 is installed at the through hole and partially extends into the pump cavity. One end of the rotating shaft 220 is connected with the motor assembly 210. The other end of the rotating shaft 220 extends into the pump cavity from the mounting channel 11 and is connected with the impeller 240, so that the impeller 240 is driven to rotate by the motor assembly 210. The static ring assembly is fixedly connected with the flange seat 1. The rotating ring assembly is fixedly connected with the rotating shaft 220. The static ring assembly and the rotating ring assembly abut against each other, thereby sealing the mounting channel 11 to prevent leakage of the medium.

[0033] Please refer to FIG. 2, the static ring assembly is installed in the mounting channel 11. The rotating ring assembly is installed on the outer periphery of the rotating shaft 220 and located in the mounting channel 11. The rotating ring assembly and the static ring assembly abut against each other in the axial direction. The end of the rotating ring assembly which faces the pump cavity has a gap 12 with the side wall of the mounting channel 11. The outer periphery of the rotating ring assembly is provided with a spiral protrusion 31 which is located in the gap 12. The conveying direction of the spiral protrusion 31 faces the pump cavity. When the rotating shaft 220 rotates, the spiral protrusion 31 pushes the medium away from the abutting position of the rotating ring assembly and the static ring assembly.

[0034] In the embodiment, the flange base 1 is installed on the pump body 230, and the flange base 1 is provided with an installation channel 11 communicating with the pump cavity, one end of the rotating shaft 220 extends into the pump cavity from the installation channel 11 and is connected with the impeller 240, the static ring assembly is installed in the installation channel 11 and annularly arranged outside the rotating shaft 220, the static ring assembly is fixedly connected with the flange base 1, the dynamic ring assembly is fixedly installed outside the rotating shaft 220 and located in the installation channel 11, and the static ring assembly and the dynamic ring assembly are sequentially arranged in the axial direction, the static ring assembly and the dynamic ring assembly abut each other to form a seal, and the outer periphery of one end of the dynamic ring assembly towards the pump cavity is provided with a spiral protrusion 31, and the static ring assembly and the spiral protrusion 31 are arranged in the direction towards the pump cavity, when the rotating shaft 220 rotates, the dynamic ring assembly and the spiral protrusion 31 can be driven to rotate, so that the medium in the gap 12 can be transported into the pump cavity, that is, when the spiral protrusion 31 rotates, a force is formed in the direction towards the pump cavity to prevent the medium particles from entering the gap 12, thereby effectively protecting the running environment of the friction pair between the dynamic ring assembly and the static ring assembly and improving the service life.

[0035] In one of the embodiments, the gap 12 ranges from 0.2mm to 0.3mm.

[0036] In the embodiment, the flange base 1 is fixedly installed on the pump body 230, the dynamic ring assembly is installed on the rotating shaft 220, and the dynamic ring assembly is located in the installation channel 11 when the rotating shaft 220 rotates, so that the flange base 1 and the dynamic ring assembly move relatively. In order to avoid wear between the two, the outer diameter of the dynamic ring assembly is generally slightly smaller than the diameter of the installation channel 11, so that the gap 12 is formed between the two to avoid friction, and the gap 12 between the two should not be too large, if the gap 12 is too large, a large amount of medium will enter and affect the sealing, and if the gap 12 is too small, it is difficult to form the spiral protrusion 31 on the outer periphery of the dynamic ring assembly, which cannot effectively prevent the medium, so the gap 12 is preferably 0.2mm to 0.3mm.

[0037] In one of the embodiments, referring to FIG. 4, the spiral protrusion 31 is an equidistant spiral protrusion 31.

[0038] In the embodiment, the spiral protrusion 31 can be understood as a spiral-shaped rib formed on the outer periphery of the dynamic ring assembly, and the rib is arranged at equal intervals to form an equidistant spiral protrusion 31.

[0039] In one embodiment, referring to Figs. 2 and 3, the rotating ring assembly comprises a rotating ring seat 3 and two rotating rings 4, the rotating ring seat 3 is sleeved on the outer periphery of the rotating shaft 220, the helical protrusion 31 is arranged on the outer periphery of the rotating ring seat 3 towards the pump cavity, and the two rotating rings 4 are axially spaced and arranged on the outer periphery of the rotating ring seat 3 and sealingly connected with the rotating ring seat 3.

[0040] In this embodiment, the rotating ring seat 3 is arranged on the rotating shaft 220, the one end of the rotating ring seat 3 towards the pump cavity is flush with the flange seat 1, the other end of the rotating ring seat 3 extends out of the mounting channel 11, one of the rotating rings 4 is arranged in the mounting channel 11 and sealingly connected with the rotating ring seat 3, the other rotating ring 4 is arranged outside the mounting channel 11 and sealingly connected with the rotating ring seat 3, and the static ring assembly is arranged between the two rotating rings 4 and abuts against the two rotating rings 4 respectively.

[0041] In one embodiment, referring to Figs. 2 and 3, the sealing structure 100 further comprises a shaft sleeve 6, the shaft sleeve 6 is arranged on the outer periphery of the rotating shaft 220, and the rotating ring seat 3 is sleeved on the outer periphery of the shaft sleeve 6 and sealingly connected with the shaft sleeve 6.

[0042] In this embodiment, the shaft sleeve 6 is further arranged on the outer periphery of the rotating shaft 220, the one end of the shaft sleeve 6 towards the pump cavity is provided with a step, the rotating ring seat 3 is provided with a stepped hole corresponding to the step, the rotating ring seat 3 is sleeved on the outer periphery of the shaft sleeve 6 and axially limited by the step, and a clamping ring 7 is further arranged on the other end of the rotating ring seat 3, the clamping ring 7 is connected with the rotating ring 4 arranged outside the mounting channel 11, so as to fix the rotating ring 4 and the rotating ring seat 3 on the shaft sleeve 6, and thus the above components can be assembled on the shaft sleeve 6 first, and then the shaft sleeve 6 is connected with the rotating shaft 220, which is convenient for production and assembly.

[0043] In one embodiment, referring to Figs. 2 and 3, the rotating ring seat 3 comprises a first section and a second section connected in sequence along the axial direction, the two rotating rings 4 are arranged on the two ends of the first section, the outer diameter of the second section is larger than that of the first section, the gap 12 is formed between the second section and the side wall of the mounting channel 11, and the helical protrusion 31 is arranged on the second section.

[0044] In the embodiment, the outer diameter of the second section is larger than the outer diameter of the first section, and the first section and the second section are connected by the connecting section, so that the dynamic ring seat 3 forms a stepped structure, the inner diameter of the first section is matched with the shaft sleeve 6, and the inner diameter of the second section is matched with the step. In this way, on the one hand, it is beneficial to form a stepped hole matched with the shaft sleeve 6 in the dynamic ring seat 3, and on the other hand, it is beneficial to install the dynamic ring 4 and the static ring assembly in the space between the first section and the side wall of the mounting channel 11, and it is also beneficial to reduce the gap 12 between the second section and the side wall of the mounting channel 11.

[0045] In the embodiment, in order to be able to prolong the axial length of the spiral protrusion 31, the second connecting section is arranged to extend towards the direction away from the pump cavity, that is, the connecting section is connected with the middle part of the second section. In this way, the length of the second section can be prolonged without increasing the overall structure, and the number of spiral turns of the spiral protrusion 31 is increased, which is beneficial to prevent the medium containing solid particles from flowing into the mounting channel 11.

[0046] In the embodiment, the first section, the connecting section and the second section enclose an annular groove, and one of the dynamic rings 4 is arranged in the groove.

[0047] In one of the embodiments, referring to FIGS. 2 and 3, the static ring assembly includes two static rings 2, which are arranged in an axial direction and located between the two dynamic rings 4. The static rings 2 are in sealing fit with the side wall of the mounting channel 11, and the two static rings 2 abut against the two dynamic rings 4 one by one.

[0048] In the embodiment, the two static rings 2 correspond to the two dynamic rings 4 one by one, and the static rings 2 are fixedly installed in the mounting channel 11. The inner diameter of the static ring 2 is larger than the outer diameter of the first section, and the static ring 2 abuts against and seals the dynamic ring 4. In this way, the sealing performance can be improved.

[0049] In one of the embodiments, a sealing cavity is enclosed between the flange seat 1, the static ring assembly and the dynamic ring assembly, and the sealing cavity is filled with isolation liquid.

[0050] In the embodiment, the static ring 2 and the dynamic ring 4 abut against each other to form a seal. In order to be able to lubricate the friction surface, a sealing cavity is enclosed between the dynamic ring 4, the dynamic ring seat 3, the static ring 2 and the flange seat 1, and isolation liquid is injected into the sealing cavity. The isolation liquid can penetrate into the friction surface, thereby playing a lubricating role.

[0051] In one of the embodiments, referring to FIG. 1 and FIG. 3, the flange base 1 is further provided with an inlet 13 communicating with the sealing cavity; the sealing structure 100 further comprises a liquid supplement station 5 communicating with the inlet 13, for delivering the isolation liquid into the sealing cavity.

[0052] In the embodiment, the isolation liquid can be delivered into the sealing cavity at any time through the liquid supplement station 5, so as to always ensure that the pressure value of the isolation liquid in the sealing cavity is greater than the pressure value of the pump outlet by 0.3 MPa, thereby ensuring that the mechanical seal is well lubricated.

[0053] In order to better understand the present application, the technical solutions of the present application are described in detail below in combination with FIG. 1 to FIG. 4:

[0054] When the rotating shaft 220 rotates, the helical protrusion 31 can be driven to rotate, so as to deliver the medium in the gap 12 into the pump cavity, that is, when the helical protrusion 31 rotates, a force is formed to hinder the medium particles from entering the gap 12 in the direction of the pump cavity, thereby effectively protecting the running environment of the friction pair between the rotating ring assembly and the static ring assembly, and improving the service life.

[0055] The specific embodiments of the present application described above do not constitute a limitation on the protection scope of the present application. Any various other corresponding changes and modifications made according to the technical concept of the present application shall be included in the protection scope of the claims of the present application.

Claims

1. A seal structure, characterized by, The sealing structure comprises: a flange seat provided with a mounting channel, the flange seat being arranged to be sleeved on the outer periphery of the rotating shaft and mounted on the pump body; a static ring assembly mounted in the mounting channel; and a dynamic ring assembly mounted on the outer periphery of the rotating shaft and located in the mounting channel, the dynamic ring assembly abutting against the static ring assembly in the axial direction, a gap being formed between the end of the dynamic ring assembly facing the pump cavity and the side wall of the mounting channel, the outer periphery of the dynamic ring assembly being provided with helical protrusions located in the gap, the conveying direction of the helical protrusions being towards the pump cavity, so that the medium is pushed away from the abutting position of the dynamic ring assembly and the static ring assembly by the helical protrusions when the rotating shaft rotates.

2. The seal structure of claim 1, wherein The gap ranges from 0.2 mm to 0.3 mm.

3. The seal structure of claim 1, wherein The helical protrusions are equidistant helical protrusions.

4. The seal structure of claim 1, wherein The dynamic ring assembly comprises a dynamic ring seat and two dynamic rings, the dynamic ring seat being sleeved on the outer periphery of the rotating shaft, the helical protrusions being arranged on the outer periphery of the end of the dynamic ring seat facing the pump cavity, and the two dynamic rings being mounted on the outer periphery of the dynamic ring seat in the axial direction and in sealing cooperation with the dynamic ring seat.

5. The seal structure of claim 4, wherein The sealing structure further comprises a shaft sleeve, the shaft sleeve being arranged on the outer periphery of the rotating shaft, and the dynamic ring seat being sleeved on the outer periphery of the shaft sleeve and in sealing cooperation with the shaft sleeve.

6. The seal structure of claim 4, wherein The dynamic ring seat comprises a first section and a second section connected in sequence in the axial direction, the two dynamic rings being mounted on the two ends of the first section, the outer diameter of the second section being greater than that of the first section, the gap being formed between the second section and the side wall of the mounting channel, and the helical protrusions being located on the second section.

7. The seal structure of claim 4, wherein The static ring assembly comprises two static rings, the two static rings being arranged in the axial direction and located between the two dynamic rings, the static rings being in sealing cooperation with the side wall of the mounting channel, and the two static rings abutting against the two dynamic rings one by one.

8. The sealed structure of claim 1, wherein, A sealing cavity is formed between the flange seat, the static ring assembly and the dynamic ring assembly, and the sealing cavity is filled with isolation liquid.

9. The sealed structure of claim 1, wherein, The flange seat is further provided with an inlet communicating with the sealing cavity. The sealing structure further comprises a liquid supplementing station, the liquid supplementing station communicating with the inlet and being used for conveying isolation liquid into the sealing cavity.

10. A centrifugal feed pump characterized by, The centrifugal feed pump comprises the sealing structure according to any one of claims 1-9.

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