Centrifugal compressor

Abstract

The utility model provides a centrifugal compressor which comprises a shell, a compressor body, a compressor body and a compressor cover. The rotating assembly is arranged in the cavity; the rotating assembly comprises a motor and a driving shaft, the motor comprises a stator and a rotor, the stator is connected with the shell, and the driving shaft is connected with the rotor of the motor; the driving shaft is rotationally connected with the shell through the supporting assembly and the shell; a cooling medium inlet and a first cooling medium outlet are formed in the positions, corresponding to the stator, of the shell, and a second cooling medium outlet and a third cooling medium outlet are formed in the positions, corresponding to the supporting assembly, of the shell. The cooling medium outlets are formed in the relative positions of the shell and the stator and the relative positions of the shell and the supporting assembly, so that the cooling medium absorbing heat is discharged out of the shell in time, the temperature of the motor is rapidly reduced, the motor operates stably, and the operation stability of the compressor is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of compressors, in particular to a centrifugal compressor. Background Art

[0002] The most commonly used evaporation and concentration system at present is the MVR (mechanical vapor recompression) system, in which the evaporation compressor is the core power component of the MVR evaporation system. The steam compressor recompresses the secondary steam generated in the evaporation process (secondary steam is generally at a low temperature and cannot be used directly) to increase its temperature and pressure, and uses it as a heat source to heat the raw liquid to be evaporated, thereby achieving the purpose of recycling the secondary steam, that is, obtaining more heat energy with a small amount of heat energy.

[0003] Commonly used steam compressor types include screw, centrifugal, and Roots types. Centrifugal compressors are widely used in various gas compression and transportation applications due to their high compression efficiency, energy efficiency, operational reliability, and adaptability. However, existing centrifugal compressors suffer from insufficient cooling during operation, impacting their operational stability. Utility Model Content

[0004] In view of the problems in the prior art, the purpose of the present invention is to provide a centrifugal compressor, which improves the cooling problem during the operation of the compressor and enhances the stability of the compression operation.

[0005] The present invention provides a centrifugal compressor comprising:

[0006] a shell having a cavity therein;

[0007] A rotating assembly is provided in the cavity; the rotating assembly includes a motor and a drive shaft, the motor includes a stator and a rotor, the stator is connected to the housing, and the drive shaft is connected to the rotor of the motor;

[0008] a support assembly, wherein the drive shaft and the housing are rotatably connected to the housing through the support assembly;

[0009] A cooling medium inlet and a first cooling medium outlet are respectively provided at positions of the housing corresponding to the stator, and a second cooling medium outlet and a third cooling medium outlet are provided at positions of the housing corresponding to the support assembly.

[0010] In some embodiments, the rotating assembly further includes at least one blade fixed on the drive shaft.

[0011] In some embodiments, the drive shaft and the blades are arranged in a single cantilever arrangement or a back-to-back arrangement.

[0012] In some embodiments, the support assembly includes a first radial bearing and a second radial bearing, the first radial bearing is sleeved on the first end of the drive shaft, and the second radial bearing is sleeved on the second end of the drive shaft.

[0013] In some embodiments, the first radial bearing and the second radial bearing are air bearings or magnetic bearings.

[0014] In some embodiments, a side of the blade close to the motor is sealed by a labyrinth seal.

[0015] In some embodiments, a first protective bearing and a second protective bearing are further included. The first protective bearing is arranged on a side of the first radial bearing away from the motor, and the second protective bearing is arranged on a side of the second radial bearing away from the motor.

[0016] In some embodiments, the motor is a permanent magnet synchronous motor.

[0017] In some embodiments, the system further includes a volute and a diffuser, wherein the volute is fixed to the end of the housing, the blades and the diffuser are placed in the volute, and the wheel of the blades is in the same plane as the diffuser.

[0018] In some embodiments, annular grooves are provided on the inner walls of the housing corresponding to the stator.

[0019] The centrifugal compression provided by the utility model has the following advantages:

[0020] The utility model provides cooling medium outlets at the relative positions of the housing and the stator and the relative positions of the support assembly, so that the cooling fluid after absorbing heat is discharged out of the housing in time, thereby quickly reducing the temperature of the motor, making the motor run stably, and improving the stability of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings.

[0022] Figure 1 This is a front view of a centrifugal compressor according to an embodiment of the present invention;

[0023] Figure 2 This is a perspective view of a centrifugal compressor according to an embodiment of the present invention;

[0024] Figure 3 is a cross-sectional view of a centrifugal compressor according to an embodiment of the present invention;

[0025] Figure 4It is a schematic diagram of the flow of cooling medium inside the shell of a centrifugal compressor according to one embodiment of the present utility model.

[0026] Reference numerals:

[0027] 10 Housing 312 Second radial bearing

[0028] 11 Cooling medium inlet 321 First protective bearing

[0029] 12 First cooling medium outlet 322 Second protective bearing

[0030] 13 Second cooling medium outlet 33 Thrust bearing

[0031] 14 Third cooling medium outlet 40 blade

[0032] 20 Rotating assembly 50 Labyrinth seal

[0033] 21 Motor 60 Volute

[0034] 211 stator 70 diffuser

[0035] 212 rotor 80 inlet guide vane

[0036] 22 drive shaft 91 connecting pipe

[0037] 30 Support assembly 92 Exhaust pipe

[0038] 311 first radial bearing DETAILED DESCRIPTION

[0039] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. In the figures, identical reference numerals denote identical or similar structures, and thus repetitive descriptions thereof will be omitted. The use of "or" and "either" in this specification may mean "and" or "or."

[0040] In the description of this application, reference to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and integrate different embodiments or examples described in this application, as well as features of different embodiments or examples, unless otherwise contradictory.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include at least one such feature. In the context of this application, "plurality" means two or more, unless otherwise specifically defined.

[0042] In order to solve the problems in the prior art, the present invention provides a centrifugal compressor. Figures 1 to 3 As shown, the centrifugal compressor provided by the embodiment of the present invention includes: a shell 10, which has a cavity inside; a rotating assembly 20, which is arranged in the cavity; the rotating assembly 20 includes a motor 21 and a drive shaft 22, the motor 21 includes a stator 211 and a rotor 212, the stator 211 is connected to the shell 10, and the drive shaft 22 is connected to the rotor 212 (in this embodiment, it can be regarded as the drive shaft 22 passing through the two ends of the rotor 212, so that the rotor 212 can drive the drive shaft 22 to rotate when it moves); a support assembly 30, the drive shaft 22 and the shell 10 are rotatably connected to the shell 10 through the support assembly 30; a cooling medium inlet 11 and a first cooling medium outlet 12 are respectively provided at positions corresponding to the stator 211, and a second cooling medium outlet 13 and a third cooling medium outlet 14 are provided at positions opposite to the support assembly 30.

[0043] When the motor is running at too high a temperature, it will affect its performance and even cause damage. Therefore, good temperature control is an important condition to ensure the normal operation of the motor and extend its service life. Figure 4As shown, the process by which the cooling medium cools the interior of the cavity is as follows: first, the cooling medium enters the cavity through the cooling medium inlet 11. Some of the cooling medium cools the motor 21 along the inner wall of the housing 10, and then flows out of the cavity through the first cooling medium outlet 12. Some of the cooling medium flows axially along the housing 10 toward the support assembly 30, thereby cooling the support assembly 30. The cooling medium, after absorbing heat, flows out of the cavity through the second cooling medium outlet 13 and the third cooling medium outlet 14. The provision of multiple cooling medium outlets allows the cooling fluid to be discharged from the cavity in a timely manner after absorbing heat, preventing excessive cooling medium from accumulating in the cavity, resulting in poor cooling effect and affecting motor operation.

[0044] It should be noted that the circumferential arrangement of the first cooling medium outlet 12, the second cooling medium outlet 12 and the third cooling medium outlet 13 on the shell 10 is not limited to that shown in this embodiment, and those skilled in the art can arrange their circumferential positions on the shell 10 according to actual needs.

[0045] Furthermore, in this embodiment, the motor 21 is a permanent magnet synchronous motor. Compared with an asynchronous motor, a permanent magnet synchronous motor can output higher power and torque at the same weight and volume, and has high transmission efficiency.

[0046] Preferably, an annular groove is provided inside the housing 10 . When the cooling medium enters the housing 10 from the cooling medium inlet 11 , the cooling medium extends toward the axial ends of the housing 10 along the direction of the annular groove to cool the motor 21 .

[0047] like Figure 3 and Figure 4 As shown, the rotating assembly 20 further includes at least one blade 40 fixed to the drive shaft 22. Figure 3 and Figure 4 As shown, the rotating assembly includes two blades 40, blade 40 (1) is provided at the first end of the drive shaft 22, and blade 40 (2) is provided at the second end of the drive shaft 22. The centrifugal compressor shown in this embodiment is a two-stage centrifugal compressor. The number of blades 40 is not limited to the number shown in the above example, and those skilled in the art can increase or decrease the number of blades 40 according to actual needs.

[0048] Furthermore, in this embodiment, the drive shaft 22 and the blades 40 are arranged back to back. In another embodiment, the drive shaft 22 and the blades 40 are arranged in a single cantilever. The specific arrangement of the drive shaft 22 and the blades 40 can be set by those skilled in the art according to actual needs and is not specifically limited here.

[0049] Furthermore, if Figure 3 and Figure 4As shown, the support assembly 30 includes a first radial bearing 311 and a second radial bearing 312. The first radial bearing 311 is mounted on the first end of the drive shaft 22, and the second radial bearing 312 is mounted on the second end of the drive shaft 22. The first radial bearing 311 and the second radial bearing 312 are used to provide radial support for the drive shaft 22. In this embodiment, the first radial bearing 311 and the second radial bearing 312 are air bearings or magnetic bearings. The air bearings or magnetic bearings are oil-free bearings that do not require lubricating oil, ensuring the cleanliness of the cavity of the housing 10. The oil-free bearings eliminate friction between the rotor and the bearings, thereby further reducing the heat generated during operation of the motor 21 and maintaining a good operating temperature for the motor 21.

[0050] Furthermore, the support assembly 30 includes a first protective bearing 321 and a second protective bearing 322. The first protective bearing 321 is disposed on the side of the first radial bearing 311 facing away from the motor 21, and the second protective bearing 322 is disposed on the side of the second radial bearing 312 facing away from the motor 21. The first and second protective bearings are used to continue supporting the operation of the drive shaft 22 in the event of a failure of the oilless bearing, thereby enhancing the stability of the compressor operation.

[0051] Furthermore, the support assembly 30 further includes a thrust bearing 33 , which is disposed on a side of the second radial bearing 312 close to the motor 21 . The thrust bearing 33 is used to provide axial support force for the drive shaft 22 .

[0052] Further, see Figure 3 , the blade 40 is sealed on the side close to the motor 21 by a labyrinth seal 50. For example, Figure 3 As shown, a labyrinth seal 50(1) is provided on the side of the blade 40(1) close to the motor 21, and a labyrinth seal 50(2) is provided on the side of the blade 40(2) close to the motor 21. The labyrinth seal 50 is used to reduce gas leakage, thereby improving the efficiency and performance of the compressor.

[0053] Please continue reading Figures 1 to 4 The centrifugal compressor provided by the embodiment of the present invention further includes a volute 60 and a diffuser 70. The volute 60 is fixed to one end of the housing 10. The blades 40 and the diffuser 70 are placed in the volute 60, and the wheel of the blade 40 and the diffuser 70 are in the same plane. For example, Figure 3 As shown, the volute 60(1) is fixed to the first end of the housing 10, the blade 40(1) and the diffuser 70(1) are placed in the volute 60(1), and the wheel of the blade 40(1) and the diffuser 70(1) are in the same plane; the volute 60(2) is fixed to the second end of the housing 10, the blade 40(2) and the diffuser 70(2) are placed in the volute 60(2), and the wheel of the blade 40(2) and the diffuser 70(2) are in the same plane.

[0054] The high-speed rotating blades 40 do work on the gas so that the gas gains energy. When the gas flows out from the blades 40 , it has a very high speed. After the high-speed gas flows through the diffuser 70 , its speed decreases and its pressure increases.

[0055] For further information, see Figure 3 The inlet end of the centrifugal compressor is provided with an inlet guide vane 80, which is used to prevent the compressor from surging. The inlet guide vane 80 is set to an opening and closing angle by an inlet guide vane actuator to reasonably set the gas flow entering the volute 60 (1).

[0056] Furthermore, if Figure 1 and Figure 2 As shown, in this embodiment, the outlet of the volute 60 (1) is connected to the inlet of the volute 60 (2) through a connecting pipe 91, and the gas compressed by the blades 40 (2) is discharged out of the compressor through an exhaust pipe 92.

[0057] The working process of the centrifugal compressor described in this embodiment is as follows: the inlet guide vane 80 opens according to a preset opening and closing angle, and the low-temperature, low-pressure gas enters the volute 60 (1). After being compressed by the high-speed rotating blades 40 (1), the high-temperature, high-pressure gas is discharged. The high-temperature, high-pressure gas is decelerated and pressurized by the diffuser 70 (1) and flows into the flow channel of the volute 60 (1). The high-pressure gas discharged through the outlet of the volute 60 (1) enters the volute 60 (2) through the connecting pipe 91 for further pressurization. The secondary pressurized high-pressure gas is finally discharged from the compressor through the exhaust pipe 92 for heat exchange.

[0058] In summary, the centrifugal compressor provided by the present invention has the following advantages:

[0059] By arranging a cooling medium inlet and a first cooling medium outlet at positions relative to the stator of the shell, and arranging a second cooling medium outlet and a third cooling medium outlet at positions relative to the support assembly, the cooling medium enters the shell from the cooling medium outlet and flows to the support assembly. The cooling medium pairs that absorb heat are discharged out of the shell from the first cooling medium outlet, the second cooling medium outlet and the third cooling medium outlet respectively, so that the cooling medium after absorbing heat can be discharged out of the shell in time, and the cooling medium after absorbing heat can be avoided from accumulating in the shell, causing abnormal operation of the motor.

[0060] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A centrifugal compressor, characterized in that: include: a shell having a cavity therein; A rotating assembly is provided in the cavity; the rotating assembly includes a motor and a drive shaft, the motor includes a stator and a rotor, the stator is connected to the housing, and the drive shaft is connected to the rotor of the motor; a support assembly, wherein the drive shaft and the housing are rotatably connected to the housing through the support assembly; A cooling medium inlet and a first cooling medium outlet are respectively provided at positions of the housing corresponding to the stator, and a second cooling medium outlet and a third cooling medium outlet are provided at positions of the housing corresponding to the support assembly.

2. The centrifugal compressor according to claim 1, wherein The rotating assembly further includes at least one blade fixed on the driving shaft.

3. The centrifugal compressor according to claim 2, characterized in that The drive shaft and the blades are arranged in a single cantilever arrangement or a back-to-back arrangement.

4. The centrifugal compressor according to claim 2, characterized in that The support assembly includes a first radial bearing and a second radial bearing. The first radial bearing is sleeved on the first end of the drive shaft, and the second radial bearing is sleeved on the second end of the drive shaft.

5. The centrifugal compressor according to claim 4, characterized in that The first radial bearing and the second radial bearing are air bearings or magnetic bearings.

6. The centrifugal compressor according to claim 2, characterized in that The side of the blade close to the motor is sealed by a labyrinth seal.

7. The centrifugal compressor according to claim 5, characterized in that It also includes a first protective bearing and a second protective bearing. The first protective bearing is arranged on a side of the first radial bearing away from the motor, and the second protective bearing is arranged on a side of the second radial bearing away from the motor.

8. The centrifugal compressor according to claim 1, wherein: The motor is a permanent magnet synchronous motor.

9. The centrifugal compressor according to claim 2, wherein: It also includes a volute and a diffuser. The volute is fixed to the end of the shell. The blades and the diffuser are placed in the volute, and the wheel disk of the blade is in the same plane as the diffuser.

10. The centrifugal compressor according to claim 1, wherein Annular grooves are provided on the inner walls of the housing corresponding to the stator.

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