Sealing structure and centrifugal feeding pump

Abstract

The utility model discloses a sealing structure and a centrifugal feeding pump, the sealing structure comprises a flange seat, a static ring assembly and a moving ring assembly, the flange seat is provided with a mounting channel, and the static ring assembly is mounted in the mounting channel; the movable ring assembly is installed on the periphery of the rotating shaft and located in the installation channel, the movable ring assembly abuts against the static ring assembly in the axial direction, a gap is formed between the end, facing the pump cavity, of the movable ring assembly and the side wall of the installation channel, and a spiral protrusion located in the gap is arranged on the periphery of the movable ring assembly. The conveying direction of the spiral protrusions faces the pump cavity so that when the rotating shaft rotates, media can be pushed away from the abutting joint position of the movable ring assembly and the static ring assembly through the spiral protrusions. According to the friction pair, when the spiral protrusion rotates, force which faces the pump cavity and prevents medium particles from entering the gap can be formed, so that the operation environment of the friction pair is effectively protected, and the service life is prolonged.

Description

Technical Field

[0001] This application relates to the field of feed pump technology, specifically to a sealing structure and a centrifugal feed pump. Background Technology

[0002] A high-temperature, high-pressure slurry preheater is a device used to store and heat high-pressure slurry. The slurry is typically a three-phase mixture of solids, liquids, and gases, with a solid content generally between 35% and 40%, the remainder being steam and acidic solutions, and a pH between 2 and 4. The preheater is usually a sealed cylindrical tank, pressurized internally. As the medium temperature rises from 105℃ to 165℃, the internal pressure correspondingly increases from 0.8MPa to 2.2MPa. The slurry is generally fed into the high-temperature, high-pressure slurry preheater via a centrifugal feed pump.

[0003] Chinese patent CN110131172A discloses a centrifugal pump with enhanced sealing, including a pump body and a rotating shaft. The pump body has an inlet, a working chamber, and an outlet. A rotational seal is established between the rotating shaft and the pump body by setting a water seal assembly. The water seal assembly includes a rotating ring, a stationary ring, a spring, and an elastic sleeve. A pressure plate is slidably arranged in the pump body. The ends of the spring and the elastic sleeve facing away from the rotating ring are located on the pressure plate. A sandwich plate is provided in the pump body, and a pressure chamber is formed between the sandwich plate and the outer wall of the pump body. The pressure chamber is connected to the working chamber near the outlet.

[0004] In the aforementioned prior art, the sides of the rotating ring and the stationary ring that are arranged opposite each other are friction surfaces. The two friction surfaces abut against each other to achieve a seal. However, when conveying slurry, the medium containing solid particles in the pump chamber will flow towards the sealing friction surface. The solid particles will cause wear on the friction surface and affect its service life. Utility Model Content

[0005] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a sealing structure and a centrifugal feed pump to solve the technical problem in the prior art where the medium containing solid particles in the pump cavity flows towards the sealing friction surface, and the solid particles cause wear on the friction surface, affecting the service life.

[0006] To achieve the above-mentioned technical objectives, the present application adopts the following technical solution:

[0007] This application provides a sealing structure, including:

[0008] A flange seat is provided with an installation channel. The flange seat is used to be fitted onto the outer circumference of the rotating shaft and installed on the pump body.

[0009] The stationary ring assembly is installed within the mounting channel; and

[0010] A rotating ring assembly is installed on the outer periphery of the rotating shaft and located within the mounting channel. The rotating ring assembly abuts against the stationary ring assembly in the axial direction. A gap exists between the end of the rotating ring assembly facing the pump cavity and the side wall of the mounting channel. A helical protrusion is provided on the outer periphery of the rotating ring assembly within the gap. The conveying direction of the helical protrusion is towards the pump cavity, so that when the rotating shaft rotates, the medium is pushed away from the abutment point between the rotating ring assembly and the stationary ring assembly by the helical protrusion. A sealing cavity is formed between the flange seat, the stationary ring assembly, and the rotating ring assembly. The sealed cavity is filled with a sealing fluid that can penetrate into the friction surface to provide lubrication. The end of the rotating ring seat facing the pump cavity is flush with the flange seat. The rotating ring assembly includes a rotating ring seat and two rotating rings. The other end of the rotating ring seat extends out of the mounting channel. One of the rotating rings is located inside the mounting channel and is sealed to the rotating ring seat. The other rotating ring is located outside the mounting channel and is sealed to the rotating ring seat. The stationary ring assembly is located between the two rotating rings and abuts against the two rotating rings respectively.

[0011] In some embodiments, the gap ranges from 0.2 mm to 0.3 mm.

[0012] In some embodiments, the spiral protrusions are equidistant spiral protrusions.

[0013] In some embodiments, the rotating ring seat is sleeved on the outer periphery of the rotating shaft, the spiral protrusion is provided on the outer periphery of the rotating ring seat facing the pump cavity, and the two rotating rings are axially spaced and installed on the outer periphery of the rotating ring seat and are sealed with the rotating ring seat.

[0014] In some embodiments, the sealing structure further includes a bushing, which is disposed on the outer periphery of the rotating shaft, and the moving ring seat is sleeved on the outer periphery of the bushing and sealably cooperates with the bushing.

[0015] In some embodiments, the moving ring seat includes a first segment and a second segment connected sequentially along the axial direction, two moving rings are installed at both ends of the first segment, the outer diameter of the second segment is larger than the outer diameter of the first segment, the second segment and the sidewall of the mounting channel form the gap, and the spiral protrusion is located in the second segment.

[0016] In some embodiments, the stationary ring assembly includes two stationary rings, which are axially spaced apart and located between the two rotating rings. The stationary rings are sealed to the sidewall of the mounting channel, and the two stationary rings abut against the two rotating rings in a one-to-one correspondence.

[0017] In some embodiments, the flange seat is further provided with an inlet communicating with the sealing cavity; the sealing structure further includes a replenishment station, which is communicating with the inlet and is used to deliver isolation fluid into the sealing cavity.

[0018] In addition, this application also provides a centrifugal feed pump, which includes the aforementioned sealing structure.

[0019] Compared with the prior art, the sealing structure provided in this application has a flange seat mounted on the pump body, and the flange seat has an installation channel communicating with the pump cavity. One end of the rotating shaft extends into the pump cavity from the installation channel and connects to the impeller. The stationary ring assembly is installed in the installation channel and surrounds the outer circumference of the rotating shaft. The stationary ring assembly is fixedly connected to the flange seat. The rotating ring assembly is fixedly installed on the outer circumference of the rotating shaft and located in the installation channel. The stationary ring assembly and the rotating ring assembly are arranged sequentially along the axial direction. The stationary ring assembly and the rotating ring assembly abut against each other to form a seal. The outer circumference of the end of the rotating ring assembly facing the pump cavity has a spiral protrusion. The stationary ring assembly and the spiral protrusion are arranged in the direction towards the pump cavity. When the rotating shaft rotates, it can drive the rotating ring assembly and the spiral protrusion to rotate, thereby transporting the medium in the gap to the pump cavity. That is, when the spiral protrusion rotates, it forms a force in the direction towards the pump cavity that prevents medium particles from entering the gap, thereby effectively protecting the operating environment of the friction pair between the rotating ring assembly and the stationary ring assembly and improving the service life.

[0020] The above description is merely an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it according to the contents of the specification, the preferred embodiments of this application are described in detail below with reference to the accompanying drawings. The specific implementation methods of this application are given in detail in the following embodiments and their accompanying drawings. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of an embodiment of the centrifugal feed pump provided in this application;

[0022] Figure 2 This is a schematic diagram of an embodiment of the sealing structure provided in this application;

[0023] Figure 3 yes Figure 2 A partial sectional view of the central sealing structure;

[0024] Figure 4 yes Figure 2 A three-dimensional schematic diagram of the moving ring seat.

[0025] Explanation of reference numerals in the attached figures:

[0026] 100-Sealing structure, 1-Flange seat, 11-Installation channel, 12-Gap, 13-Inlet, 2-Stationary ring, 3-Dynamic ring seat, 31-Spiral protrusion, 4-Dynamic ring, 5-Replenishment station, 6-Shaft sleeve, 7-Clamping ring, 200-Centrifugal feed pump, 210-Motor assembly, 220-Rotating shaft, 230-Pump body, 240-Impeller. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0028] To address the technical problem in existing technologies where media containing solid particles flow towards the sealing friction surface within the pump cavity, causing wear and affecting service life, this application provides a sealing structure that can transport the media within the gap into the pump cavity. Specifically, when the spiral protrusion rotates, it generates a force towards the pump cavity that prevents media particles from entering the gap, thereby effectively protecting the operating environment of the friction pair between the dynamic ring assembly and the stationary ring assembly and improving service life.

[0029] Please see Figure 1 This application provides a centrifugal feed pump 200, which includes the aforementioned sealing structure 100, motor assembly 210, rotating shaft 220, pump body 230, and impeller 240. The sealing structure 100 includes a flange seat 1, a stationary ring assembly, and a rotating ring assembly. The flange seat 1 is provided with an installation channel 11. The pump body 230 forms a pump cavity, and the pump body 230 also has a through hole in the middle communicating with the pump cavity. The impeller 240 is rotatably mounted in the pump cavity, and the flange seat 1 is installed in the through hole. The rotating shaft 220 extends into the pump chamber, with one end connected to the motor assembly 210 and the other end extending into the pump chamber from the mounting channel 11 and connected to the impeller 240. The motor assembly 210 drives the impeller 240 to rotate. The stationary ring assembly is fixedly connected to the flange seat 1, and the rotating ring assembly is fixedly connected to the rotating shaft 220. The stationary ring assembly and the rotating ring assembly abut against each other, thereby sealing the mounting channel 11 to prevent media leakage.

[0030] Please see Figure 2 The stationary ring assembly is installed within the mounting channel 11; the rotating ring assembly is installed on the outer periphery of the rotating shaft 220 and located within the mounting channel 11. The rotating ring assembly and the stationary ring assembly abut against each other in the axial direction. There is a gap 12 between the end of the rotating ring assembly facing the pump cavity and the side wall of the mounting channel 11. The outer periphery of the rotating ring assembly is provided with a spiral protrusion 31 located within the gap 12. The conveying direction of the spiral protrusion 31 is towards the pump cavity, so that when the rotating shaft 220 rotates, the medium is pushed away from the abutment point between the rotating ring assembly and the stationary ring assembly through the spiral protrusion 31.

[0031] In this embodiment, the flange seat 1 is mounted on the pump body 230, and the flange seat 1 has an installation channel 11 communicating with the pump chamber. One end of the rotating shaft 220 extends into the pump chamber through the installation channel 11 and connects to the impeller 240. The stationary ring assembly is installed inside the installation channel 11 and surrounds the outer periphery of the rotating shaft 220. The stationary ring assembly is fixedly connected to the flange seat 1. The rotating ring assembly is fixedly installed on the outer periphery of the rotating shaft 220 and located inside the installation channel 11. The stationary ring assembly and the rotating ring assembly are arranged sequentially along the axial direction. The rotating ring assembly forms a seal by abutting against each other. The outer periphery of the end of the rotating ring assembly facing the pump cavity is provided with a spiral protrusion 31, and the stationary ring assembly and the spiral protrusion 31 are arranged in the direction towards the pump cavity. When the rotating shaft 220 rotates, it can drive the rotating ring assembly and the spiral protrusion 31 to rotate, thereby enabling the medium in the gap 12 to be transported into the pump cavity. That is, when the spiral protrusion 31 rotates, it forms a force in the direction towards the pump cavity that prevents medium particles from entering the gap 12, thereby effectively protecting the operating environment of the friction pair between the rotating ring assembly and the stationary ring assembly and improving its service life.

[0032] In one embodiment, the gap 12 ranges from 0.2 mm to 0.3 mm.

[0033] In this embodiment, the flange seat 1 is fixedly mounted on the pump body 230, and the rotating ring assembly is mounted on the rotating shaft 220. As the rotating shaft 220 rotates, the rotating ring assembly is still located within the mounting channel 11. Therefore, relative movement occurs between the flange seat 1 and the rotating ring assembly. To avoid wear between the two, the outer diameter of the rotating ring assembly is generally slightly smaller than the diameter of the mounting channel 11, so that a gap 12 is formed between them to avoid friction. The gap 12 should not be too large, otherwise a large amount of medium will enter it and affect the seal. It should also not be too small, otherwise it will be difficult to form a spiral protrusion 31 on the outer periphery of the rotating ring assembly, and it will not be able to effectively stop the medium. Therefore, a gap 12 of 0.2mm-0.3mm is preferred.

[0034] In one embodiment, please refer to Figure 4 The spiral protrusion 31 is an equidistant spiral protrusion 31.

[0035] In this embodiment, the spiral protrusion 31 can be understood as a spiral rib formed on the outer periphery of the moving ring assembly. The ribs are arranged at equal intervals to form equidistant spiral protrusions 31.

[0036] In one embodiment, please refer to Figure 2 and Figure 3The rotating ring assembly includes 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 spiral protrusion 31 is provided on the outer periphery of the rotating ring seat 3 facing the pump cavity. The two rotating rings 4 are axially spaced on the outer periphery of the rotating ring seat 3 and are sealed with the rotating ring seat 3.

[0037] In this embodiment, the rotating ring seat 3 is mounted on the rotating shaft 220. One end of the rotating ring seat 3 facing the pump cavity is flush with the flange seat 1, and the other end of the rotating ring seat 3 extends out of the mounting channel 11. One of the rotating rings 4 is located inside the mounting channel 11 and is sealed to the rotating ring seat 3, and the other rotating ring 4 is located outside the mounting channel 11 and is sealed to the rotating ring seat 3. The stationary ring assembly is located between the two rotating rings 4 and abuts against the two rotating rings 4 respectively.

[0038] In one embodiment, please refer to Figure 2 and Figure 3 The sealing structure 100 also includes a bushing 6, which is disposed on the outer periphery of the rotating shaft 220. The moving ring seat 3 is sleeved on the outer periphery of the bushing 6 and is in sealing cooperation with the bushing 6.

[0039] In this embodiment, a bushing 6 is also provided on the outer periphery of the rotating shaft 220. The bushing 6 has a step on the outer periphery of one end facing the pump cavity. The moving ring seat 3 has a corresponding step hole. The moving ring seat 3 is sleeved on the outer periphery of the bushing 6 and is axially limited by the step. A clamping ring 7 is also provided at the other end of the moving ring seat 3. The clamping ring 7 is connected to the moving ring 4 located outside the mounting channel 11 to fix the moving ring 4 and the moving ring seat 3 on the bushing 6. This arrangement allows the above-mentioned components to be assembled onto the bushing 6 first, and then the bushing 6 to the rotating shaft 220, which is convenient for production assembly.

[0040] In one embodiment, please refer to Figure 2 and Figure 3 The moving ring seat 3 includes a first section and a second section connected sequentially along the axial direction. Two moving rings 4 are installed at both ends of the first section. The outer diameter of the second section is larger than the outer diameter of the first section. The gap 12 is formed between the second section and the side wall of the mounting channel 11. The spiral protrusion 31 is located in the second section.

[0041] In this embodiment, the outer diameter of the second segment is larger than that of the first segment, and the first segment and the second segment are connected by a connecting segment, so that the moving ring seat 3 forms a stepped structure. The inner diameter of the first segment is adapted to the bushing 6, and the inner diameter of the second segment is adapted to the step. This arrangement is beneficial in two ways: firstly, it facilitates the formation of a stepped hole adapted to the bushing 6 inside the moving ring seat 3; secondly, it facilitates the installation of the moving ring 4 and the stationary ring assembly in the space between the first segment and the side wall of the mounting channel 11; and thirdly, it helps to reduce the gap 12 between the second segment and the side wall of the mounting channel 11.

[0042] In this embodiment, in order to extend the axial length of the spiral protrusion 31, the second connecting section extends away from the pump cavity, that is, the connecting section is connected to the middle of the second section. This arrangement can extend the length of the second section without increasing the overall structure, thereby increasing the number of spiral turns of the spiral protrusion 31, which is beneficial to prevent the medium containing solid particles from flowing into the installation channel 11.

[0043] In this embodiment, the first segment, the connecting segment, and the second segment enclose an annular groove, and one of the moving rings 4 is disposed within the groove.

[0044] In one embodiment, please refer to Figure 2 and Figure 3 The stationary ring assembly includes two stationary rings 2, which are axially spaced and located between the two moving rings 4. The stationary rings 2 are sealed to the side wall of the mounting channel 11, and the two stationary rings 2 and the two moving rings 4 are in one-to-one contact.

[0045] In this embodiment, the two stationary rings 2 correspond one-to-one with the two moving rings 4. The stationary rings 2 are fixedly installed in the installation channel 11. The inner diameter of the stationary rings 2 is larger than the outer diameter of the first section. The stationary rings 2 and the moving rings 4 abut against each other to seal. This arrangement can improve the sealing performance.

[0046] In one embodiment, a sealing cavity is formed between the flange seat 1, the stationary ring assembly, and the moving ring assembly, and the sealing cavity is filled with a sealing fluid.

[0047] In this embodiment, the stationary ring 2 and the rotating ring 4 abut against each other to form a seal. In order to lubricate the friction surface, a sealing cavity is formed between the rotating ring 4, the rotating ring seat 3, the stationary ring 2 and the flange seat 1. The sealing cavity is filled with a sealing liquid, which can penetrate into the friction surface to play a lubricating role.

[0048] In one embodiment, please refer to Figure 1 and Figure 3The flange seat 1 is also provided with an inlet 13 that communicates with the sealing cavity; the sealing structure 100 also includes a liquid replenishment station 5, which is connected to the inlet 13 and is used to deliver isolation liquid into the sealing cavity.

[0049] In this embodiment, the fluid replenishment station 5 can deliver isolation fluid into the sealing cavity at any time, ensuring that the pressure of the isolation fluid in the sealing cavity is always greater than the pump outlet pressure by 0.3 MPa, thereby ensuring that the mechanical seal is well lubricated.

[0050] To better understand this application, the following is combined with... Figures 1 to 4 The technical solution of this application is described in detail below:

[0051] When the shaft 220 rotates, it can drive the spiral protrusion 31 to rotate, thereby transporting the medium in the gap 12 into the pump chamber. That is, when the spiral protrusion 31 rotates, it forms a force in the direction of the pump chamber that prevents medium particles from entering the gap 12, thereby effectively protecting the operating environment of the friction pair between the dynamic ring assembly and the stationary ring assembly and improving its service life.

[0052] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of the claims of this application.

Claims

1. A sealing structure, characterized in that, It includes: A flange seat is provided with an installation channel. The flange seat is used to be fitted onto the outer circumference of the rotating shaft and installed on the pump body. The stationary ring assembly is installed within the mounting channel; as well as A rotating ring assembly is installed on the outer periphery of the rotating shaft and located within the mounting channel. The rotating ring assembly abuts against the stationary ring assembly in the axial direction. A gap exists between the end of the rotating ring assembly facing the pump cavity and the side wall of the mounting channel. A helical protrusion is provided on the outer periphery of the rotating ring assembly within the gap. The conveying direction of the helical protrusion is towards the pump cavity, so that when the rotating shaft rotates, the medium is pushed away from the abutment point between the rotating ring assembly and the stationary ring assembly by the helical protrusion. A sealing cavity is formed between the flange seat, the stationary ring assembly, and the rotating ring assembly. The sealed cavity is filled with a sealing fluid that can penetrate into the friction surface to provide lubrication. The rotating ring assembly includes a rotating ring seat and two rotating rings. One end of the rotating ring seat facing the pump cavity is flush with the flange seat, and the other end of the rotating ring seat extends out of the mounting channel. One of the rotating rings is located inside the mounting channel and is sealed to the rotating ring seat, while the other rotating ring is located outside the mounting channel and is sealed to the rotating ring seat. The stationary ring assembly is located between the two rotating rings and abuts against each of the two rotating rings.

2. The sealing structure according to claim 1, characterized in that, The gap ranges from 0.2mm to 0.3mm.

3. The sealing structure according to claim 1, characterized in that, The spiral protrusions are equidistant spiral protrusions.

4. The sealing structure according to claim 1, characterized in that, The rotating ring seat is sleeved on the outer circumference of the rotating shaft, and the spiral protrusion is provided on the outer circumference of the rotating ring seat facing the pump cavity. The two rotating rings are installed axially spaced on the outer circumference of the rotating ring seat and are sealed with the rotating ring seat.

5. The sealing structure according to claim 4, characterized in that, The sealing structure also includes a bushing, which is disposed on the outer circumference of the rotating shaft, and the moving ring seat is sleeved on the outer circumference of the bushing and seals with the bushing.

6. The sealing structure according to claim 4, characterized in that, The moving ring seat includes a first section and a second section connected sequentially along the axial direction. Two moving rings are installed at both ends of the first section. The outer diameter of the second section is larger than the outer diameter 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 in the second section.

7. The sealing structure according to claim 4, characterized in that, The stationary ring assembly includes two stationary rings, which are axially spaced and located between the two rotating rings. The stationary rings are sealed to the side wall of the mounting channel, and the two stationary rings abut against the two rotating rings in a one-to-one correspondence.

8. The sealing structure according to claim 1, characterized in that, The flange seat is also provided with an inlet that communicates with the sealing cavity; The sealing structure also includes a replenishment station, which is connected to the inlet and is used to deliver isolation fluid into the sealing cavity.

9. A centrifugal feed pump, characterized in that, The centrifugal feed pump includes the sealing structure as described in any one of claims 1-8.

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