Shaft end sealing structure and centrifugal compressor

Abstract

The utility model belongs to the technical field of centrifugal compressors, and particularly provides a shaft end sealing structure and a centrifugal compressor, the shaft end sealing structure comprises an end cover, a first sealing structure and a second sealing structure, a shaft hole is formed in the end cover, a rotating shaft penetrates through the shaft hole, and a limiting boss is arranged on the hole wall of the shaft hole; the first sealing structure is arranged on the first direction side of the limiting boss, the limiting boss is used for limiting the first sealing structure in the opposite direction of the first direction, the second sealing structure is arranged on the first direction side of the first sealing structure, and the second sealing structure is used for limiting the first sealing structure in the first direction. According to the sealing structure, the limiting boss and the second sealing structure are arranged on the two sides of the first sealing structure in the axial direction correspondingly, the first sealing structure can be axially positioned by replacing a bolt combining mode, and therefore the first sealing structure is independently installed different from the end cover; and the first sealing structure is prevented from being damaged due to collision with the rotating shaft when being assembled on the end cover.

Description

Technical Field

[0001] The present application belongs to the technical field of centrifugal compressors, and in particular relates to a shaft end sealing structure and a centrifugal compressor. Background Art

[0002] The compressor end cover is a component that bears the internal pressure of the compressor. The seal between the stator and the rotor of the compressor adopts a shaft end comb seal that fits with the end cover. The shaft end seal is usually made of aluminum or other softer materials. In order to reduce leakage, the gap between the shaft end seal and the rotor is small.

[0003] When installing the shaft end seal, first fit the shaft end seal on the end cover, and then axially install the end cover into the compressor. Since the end cover is heavy, the shaft end seal fitted on the end cover is prone to collision with the rotor and damage when the end cover is axially installed, seriously affecting the sealing effect of the compressor; at the same time, replacing the damaged shaft end seal requires disassembling the end cover, which is not conducive to regular maintenance of the compressor. Utility Model Content

[0004] Therefore, the technical problem to be solved by the present application is to provide a shaft end sealing structure and a centrifugal compressor, in which the comb-teeth seal does not need to be bolted to the end cover, and the end cover can be installed first and then the comb-teeth seal can be installed.

[0005] In order to solve the above problems, one aspect of the present application provides a shaft end sealing structure, including an end cover, a first sealing structure and a second sealing structure, the end cover is provided with an axial hole, the axial hole is used to pass the rotating shaft, a limiting boss is provided on the hole wall of the axial hole, the first sealing structure is arranged on the first direction side of the limiting boss, the limiting boss is used to limit the first sealing structure in the opposite direction of the first direction, the second sealing structure is arranged on the first direction side of the first sealing structure, the second sealing structure is used to limit the first sealing structure in the first direction.

[0006] Optionally, outer walls of the first sealing structure and the second sealing structure abut against the hole wall of the shaft hole, and the hole wall of the shaft hole is used to limit the first sealing structure and the second sealing structure in the radial direction of the rotating shaft.

[0007] Optionally, the first sealing structure is a stepped type, comprising a first step and a second step, the diameter of the first step being greater than the diameter of the second step, and when the first sealing structure abuts against the limiting boss, the second step is located between the limiting boss and the rotating shaft.

[0008] Optionally, a positioning pin is provided on the outer wall of the first step, and a limiting groove is opened on the inner wall of the limiting boss, the limiting groove extends along the axial direction of the rotating shaft and passes through the limiting boss, the positioning pin is slidably provided in the limiting groove, and the limiting groove is used to limit the positioning pin in the circumferential direction of the rotating shaft.

[0009] Optionally, the limiting groove is semicircular.

[0010] Optionally, the second sealing structure is rotatably connected to one end away from the first sealing structure with a positioning key, and the positioning key is suitable for switching between a first position and a second position. A key slot is also provided on the wall of the axial hole, and the key slot extends along the circumferential direction of the rotating shaft. When the positioning key is switched to the first position, the positioning key moves into the key slot, and the key slot is used to limit the positioning key in the axial direction of the rotating shaft.

[0011] Optionally, a disassembly hole matching a disassembly tool is formed at one end of the first sealing structure close to the second sealing structure.

[0012] Optionally, the first sealing structure is a comb teeth seal.

[0013] Optionally, the second sealing structure is a dry gas seal.

[0014] Another aspect of the present application provides a centrifugal compressor, comprising the shaft end sealing structure described in any one of the above.

[0015] Beneficial Effects

[0016] In an embodiment of the utility model, a shaft end sealing structure and a centrifugal compressor are provided, wherein the shaft end sealing structure can limit the first sealing structure in the direction toward the limiting boss by setting a limiting boss, and at the same time, by setting a second sealing structure in series with the first sealing structure on the side of the first sealing structure away from the limiting boss, the first sealing structure can be limited in the direction toward the second sealing structure. The first sealing structure can be axially positioned in place of the bolt-fitting method, so that the first sealing structure can be installed separately from the end cover, thereby avoiding collision and damage between the first sealing structure and the rotating shaft when the first sealing structure is installed on the end cover; at the same time, the first sealing structure can be disassembled separately without removing the end cover, thereby reducing the difficulty of regular maintenance of the first sealing structure and improving the maintenance efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of a centrifugal compressor of an optional embodiment provided in the present application;

[0018] Figure 2 for Figure 1The enlarged view of point A in the middle;

[0019] Figure 3 for Figure 2 Axial view at B.

[0020] The reference numerals are as follows:

[0021] 1. End cover; 11. Shaft hole; 111. Limiting boss; 2. First sealing structure; 3. Second sealing structure; 4. Positioning pin; 5. Limiting groove; 6. Positioning key; 7. Keyway; 8. Disassembly hole. DETAILED DESCRIPTION

[0022] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0025] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0026] See also Figures 1 to 3As shown, according to one aspect of an embodiment of the present application, a shaft end sealing structure is provided, including an end cover 1, a first sealing structure 2 and a second sealing structure 3, the end cover 1 is provided with an axial hole 11, the axial hole 11 is used to pass the rotating shaft, a limiting boss 111 is provided on the hole wall of the axial hole 11, the first sealing structure 2 is arranged on the first direction side of the limiting boss 111, the limiting boss 111 is used to limit the first sealing structure 2 in the opposite direction of the first direction, the second sealing structure 3 is arranged on the first direction side of the first sealing structure 2, the second sealing structure 3 is used to limit the first sealing structure 2 in the first direction.

[0027] The shaft end sealing structure provided in the embodiment of the present application can limit the first sealing structure 2 in the direction of the first sealing structure 2 toward the limiting boss 111 by setting a limiting boss 111, and at the same time, by setting a second sealing structure 3 in series with the first sealing structure 2 on the side of the first sealing structure 2 away from the limiting boss 111, the first sealing structure 2 can be limited in the direction of the first sealing structure 2 toward the second sealing structure 3. The first sealing structure 2 can be axially positioned in place of the bolt-fitting method, so that the first sealing structure 2 can be installed separately from the end cover 1, avoiding the first sealing structure 2 from colliding with the rotating shaft and being damaged when it is installed on the end cover 1; at the same time, the first sealing structure 2 can be disassembled separately without removing the end cover 1, thereby reducing the difficulty of regular maintenance of the first sealing structure 2 and improving the maintenance efficiency.

[0028] The shaft end sealing structure can be applied to equipment such as compressors or oil pumps. In the embodiment of the present application, the shaft end sealing structure is applied to a centrifugal compressor.

[0029] The end cover 1 is roughly annular, and has an axial hole 11 in the middle of the end cover 1, which penetrates the end cover 1 along the axial direction of the end cover 1. The axial hole 11 is used to pass the rotating shaft, which is the rotor of the centrifugal compressor, and the rotating shaft passes through the end cover 1 through the axial hole 11 and is connected to the coupling.

[0030] The first sealing structure 2 is disposed in the shaft hole 11 . The first sealing structure 2 can be used as a shaft seal for the rotating shaft. The first sealing structure 2 is used to prevent leakage of the medium in the centrifugal compressor.

[0031] Specifically, a limiting boss 111 is provided on the hole wall of the axial hole 11. The limiting boss 111 is roughly circular. The limiting boss 111 is arranged on the opposite direction side of the first direction of the first sealing structure 2. The first sealing structure 2 is abutted against the limiting boss 111. The limiting boss 111 is used to limit the first sealing structure 2 in the opposite direction of the first direction.

[0032] The first direction may be a direction from the first sealing structure 2 toward the coupling, and the first direction side may be a side of the coupling relative to the first sealing structure 2 .

[0033] The second sealing structure 3 is also arranged in the shaft hole 11, and the second sealing mechanism can also be used as a shaft seal for the rotating shaft. The second sealing structure 3 is connected in series with the first sealing structure 2, and the second sealing structure 3 is used to further prevent leakage of the medium in the centrifugal compressor.

[0034] Specifically, the second sealing structure 3 is arranged on the first direction side of the first sealing structure 2, the second sealing structure 3 is relatively fixed to the end cover 1, the first sealing structure 2 abuts against the second sealing structure 3, and the second sealing structure 3 is used to limit the first sealing structure 2 in the first direction.

[0035] It can be understood that the limiting boss 111 and the second sealing structure 3 are respectively provided on both sides of the axial direction of the first sealing structure 2, and the limiting boss 111 and the second sealing structure 3 are used to axially position the first sealing structure 2, and can replace the bolt-fitting method to axially position the first sealing structure 2, so as to realize the installation of the first sealing structure 2 separately from the end cover 1, and avoid the first sealing structure 2 being damaged by collision with the rotating shaft when being installed on the end cover 1; at the same time, the first sealing structure 2 can be disassembled separately without removing the end cover 1, which reduces the difficulty of regular maintenance of the first sealing structure 2 and improves the maintenance efficiency.

[0036] The installation process of the shaft end sealing structure provided in the embodiment of the present application is as follows: first, bolt the end cover 1 to the centrifugal compressor casing, then move the first sealing structure 2 into the shaft hole 11 of the end cover 1 and push the first sealing structure 2 to abut against the limiting boss 111, then move the second sealing structure 3 into the shaft hole 11 of the end cover 1 and push the second sealing structure to abut against the first sealing structure, and finally fix the position of the second sealing structure 3 to complete the axial positioning of the first sealing structure 2. When disassembling the first sealing structure 2, the above-mentioned installation process of the first sealing structure 2 is reversed.

[0037] In some possible implementations provided in this application, see Figure 2 As shown, the outer walls of the first sealing structure 2 and the second sealing structure 3 abut against the hole wall of the shaft hole 11, and the hole wall of the shaft hole 11 is used to limit the first sealing structure 2 and the second sealing structure 3 in the radial direction of the rotating shaft.

[0038] By arranging the outer walls of the first sealing structure 2 and the second sealing structure 3 to abut against the hole walls of the shaft hole 11, the first sealing structure 2 and the second sealing structure 3 can be radially positioned to ensure that the concentricity of the first sealing structure 2 and the second sealing structure 3 and the rotating shaft are consistent, thereby improving the sealing effect of the first sealing structure 2 and the second sealing structure 3.

[0039] In some possible implementations provided in this application, see Figure 2 As shown, the first sealing structure 2 is of a stepped type.

[0040] By setting the first sealing structure 2 to be stepped, the projection area of ​​the first sealing structure 2 on the rotating shaft can be increased, thereby improving the sealing effect.

[0041] The first sealing structure 2 includes a first step and a second step, and both the first step and the second step may be circular.

[0042] Specifically, the diameter of the first step is greater than the diameter of the second step, and the first step is arranged on the side of the second step close to the second sealing structure 3. When the first sealing structure 2 abuts against the limiting boss 111, the end surface of the first step close to the second step abuts against the limiting boss 111, and at this time, the second step is located between the limiting boss 111 and the rotating shaft.

[0043] It is understandable that, if the first sealing structure 2 is in the shape of a circular ring, when the first sealing structure 2 abuts against the limiting boss 111 , there is no sealing material between the limiting boss 111 and the rotating shaft.

[0044] In some possible implementations provided in this application, see Figure 2 and Figure 3 As shown, a positioning pin 4 is provided on the outer wall of the first step, and a limiting groove 5 is provided on the inner wall of the limiting boss 111. The limiting groove 5 extends along the axial direction of the rotating shaft and passes through the limiting boss 111. The positioning pin 4 is slidably arranged in the limiting groove 5, and the limiting groove 5 is used to limit the positioning pin 4 in the circumferential direction of the rotating shaft.

[0045] The positioning pin 4 may be cylindrical or the like.

[0046] Specifically, the positioning pin 4 is arranged on the outer wall of the first sealing structure 2, and the positioning pin 4 is perpendicular to the axis of the rotating shaft. In the embodiment of the present application, the positioning pin 4 is arranged on the outer wall of the second step.

[0047] The limiting groove 5 may be a rectangular groove or an arc groove or the like.

[0048] Specifically, the limiting groove 5 is arranged on the hole wall of the shaft hole 11, and the limiting groove 5 extends along the axial direction of the rotating shaft. In the embodiment of the present application, the limiting groove 5 is arranged on the inner wall of the limiting boss 111, and the limiting groove 5 passes through the limiting boss 111 along the axial direction of the rotating shaft.

[0049] It can be understood that the length of the positioning pin 4 is smaller than the diameter difference between the first step and the second step. In the process of pushing the first sealing structure 2 to abut against the limiting boss 111, the positioning pin 4 slides in the limiting groove 5 along the axial direction of the rotating shaft. The limiting groove 5 is used to limit the positioning pin 4 and the first sealing structure 2 in the circumferential direction of the rotating shaft, thereby playing an anti-rotation role and ensuring that the first sealing structure 2 and the rotating shaft are stationary in the circumferential direction, thereby improving the sealing effect of the first sealing structure 2.

[0050] In some possible implementations provided in this application, see Figure 3 As shown, the limiting groove 5 is semicircular.

[0051] Compared with the limiting groove 5 being rectangular, the limiting groove 5 is set to be semicircular, which is easier to process and does not require cutting, thereby improving the processing efficiency and reducing the production cost.

[0052] In some possible implementations provided in this application, see Figure 2 As shown, the second sealing structure 3 is rotatably connected to one end away from the first sealing structure 2 with a positioning key 6, and the positioning key 6 is suitable for switching between a first position and a second position. A key groove 7 is also provided on the hole wall of the axial hole 11, and the key groove 7 extends along the circumferential direction of the rotating shaft. When the positioning key 6 is switched to the first position, the positioning key 6 moves into the key groove 7, and the key groove 7 is used to limit the positioning key 6 in the axial direction of the rotating shaft.

[0053] The positioning key 6 is rotatably connected to the end of the second sealing structure 3 away from the first sealing structure 2 , and a keyway 7 is provided on the inner wall of the shaft hole 11 , so that the second sealing structure 3 can be axially positioned when the positioning key 6 moves into the keyway 7 .

[0054] The positioning key 6 can be a rectangular or cylindrical metal rod, and is disposed on a side of the second sealing structure 3 away from the first sealing structure 2, and the positioning key 6 is rotatably connected to the second sealing structure 3. For example, the positioning key 6 is rotatably connected to the second sealing structure 3 via a rotating shaft.

[0055] The keyway 7 may be an annular groove, and the keyway 7 is provided on the hole wall of the shaft hole 11 .

[0056] Specifically, the rotation track of the positioning key 6 is located on the end surface of the second sealing structure 3 away from the first sealing structure 2. When the positioning key 6 rotates, the positioning key 6 can switch between the first position and the second position. When the positioning key 6 rotates to the first position, the end of the positioning key 6 is located in the key slot 7, and the second sealing structure 3 can be axially positioned at this time; when the positioning key 6 rotates to the second position, the end of the positioning key 6 is out of the key slot 7, and the second sealing structure 3 can be disassembled.

[0057] In some possible implementations provided in this application, see Figure 2 As shown, a disassembly hole 8 matching with a disassembly tool is formed at one end of the first sealing structure 2 close to the second sealing structure 3 .

[0058] By providing a disassembly hole 8 matching with a disassembly tool at one end of the first sealing structure 2 close to the second sealing structure 3, it is convenient to push the first sealing structure 2 to move in the shaft hole 11, thereby improving the disassembly efficiency of the first sealing structure 2.

[0059] Among them, in the embodiment of the present application, the disassembly hole 8 is a threaded hole.

[0060] Specifically, a disassembly tool may be threaded in the disassembly hole 8 , and by pushing and pulling the disassembly tool, the first sealing structure 2 may be driven to move in the shaft hole 11 , thereby achieving the purpose of disassembling the first sealing structure 2 .

[0061] In some possible embodiments provided in the present application, the first sealing structure 2 is a comb seal.

[0062] Among them, the comb tooth seal has strong adaptability and long service life. It is suitable for various fluid media, including high temperature, high pressure, corrosion, wear and other harsh working conditions, and has good wear resistance.

[0063] In some possible embodiments provided in the present application, the second sealing structure 3 is a dry gas seal.

[0064] Among them, dry gas seals have stable and reliable operation, low sealing power consumption, small leakage, and low operating temperature. They can achieve zero leakage or extremely low leakage rate of the medium, effectively protecting the medium environment and avoiding pollution and loss. At the same time, due to its non-contact operation characteristics, it has less wear, high stability, relatively low maintenance costs, and good economic benefits.

[0065] Another aspect of an embodiment of the present application provides a centrifugal compressor, comprising a shaft end sealing structure as described above.

[0066] The process of installing the shaft end sealing structure of the centrifugal compressor provided in the embodiment of the present application is: first, the end cover 1 is installed on the centrifugal compressor casing by bolting, and then the positioning pin 4 is fixed on the first sealing structure 2, and then the disassembly tool is used to push the first sealing structure 2 to move in the shaft hole 11 through the disassembly hole 8 until the positioning pin 4 is inserted into the limiting groove 5 and the first sealing structure 2 is abutted against the limiting boss 111, and then the second sealing structure 3 is installed, and finally the positioning key 6 is turned to the first position.

[0067] In an embodiment of the present application, a shaft end sealing structure and a centrifugal compressor are provided, wherein the shaft end sealing structure can limit the first sealing structure 2 in the direction of the first sealing structure 2 toward the limiting boss 111 by setting a limiting boss 111, and at the same time, by setting a second sealing structure 3 in series with the first sealing structure 2 on the side of the first sealing structure 2 away from the limiting boss 111, the first sealing structure 2 can be limited in the direction of the first sealing structure 2 toward the second sealing structure 3, and the first sealing structure 2 can be axially positioned instead of the bolt-fitting method, so that the first sealing structure 2 can be installed separately from the end cover 1, avoiding the first sealing structure 2 from colliding with the rotating shaft and being damaged when it is installed on the end cover 1; at the same time, the first sealing structure 2 can be disassembled separately without removing the end cover 1, thereby reducing the difficulty of regular maintenance of the first sealing structure 2 and improving the maintenance efficiency.

[0068] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0069] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A shaft end sealing structure, characterized in that: The invention comprises an end cover (1), a first sealing structure (2) and a second sealing structure (3); the end cover (1) is provided with an axial hole (11), the axial hole (11) is used to pass a rotating shaft, a limiting boss (111) is provided on the hole wall of the axial hole (11), the first sealing structure (2) is arranged on a first direction side of the limiting boss (111), the limiting boss (111) is used to limit the first sealing structure (2) in a direction opposite to the first direction, the second sealing structure (3) is arranged on the first direction side of the first sealing structure (2), the second sealing structure (3) is used to limit the first sealing structure (2) in the first direction.

2. The shaft end sealing structure according to claim 1, characterized in that: The outer walls of the first sealing structure (2) and the second sealing structure (3) abut against the hole wall of the shaft hole (11), and the hole wall of the shaft hole (11) is used to limit the first sealing structure (2) and the second sealing structure (3) in the radial direction of the rotating shaft.

3. The shaft end sealing structure according to claim 1, characterized in that: The first sealing structure (2) is of a stepped type, comprising a first step and a second step, the diameter of the first step being greater than the diameter of the second step, and when the first sealing structure (2) is in contact with the limiting boss (111), the second step is located between the limiting boss (111) and the rotating shaft.

4. The shaft end sealing structure according to claim 3, characterized in that: A positioning pin (4) is provided on the outer wall of the first step, and a limiting groove (5) is provided on the inner wall of the limiting boss (111). The limiting groove (5) extends along the axial direction of the rotating shaft and passes through the limiting boss (111). The positioning pin (4) is slidably arranged in the limiting groove (5), and the limiting groove (5) is used to limit the positioning pin (4) in the circumferential direction of the rotating shaft.

5. The shaft end sealing structure according to claim 4, characterized in that: The limiting groove (5) is semicircular.

6. The shaft end sealing structure according to claim 1, characterized in that: The second sealing structure (3) is rotatably connected to one end away from the first sealing structure (2) with a positioning key (6), and the positioning key (6) is suitable for switching between a first position and a second position. The hole wall of the shaft hole (11) is also provided with a key groove (7), and the key groove (7) extends along the circumferential direction of the rotating shaft. When the positioning key (6) is switched to the first position, the positioning key (6) moves into the key groove (7), and the key groove (7) is used to limit the positioning key (6) in the axial direction of the rotating shaft.

7. The shaft end sealing structure according to claim 1, characterized in that: An assembly and disassembly hole (8) matching an assembly and disassembly tool is provided at one end of the first sealing structure (2) close to the second sealing structure (3).

8. The shaft end sealing structure according to claim 1, characterized in that: The first sealing structure (2) is a comb seal.

9. The shaft end sealing structure according to claim 1, characterized in that: The second sealing structure (3) is a dry gas seal.

10. A centrifugal compressor, characterized in that: The invention comprises the shaft end sealing structure as described in any one of claims 1 to 9.

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