CN109869327B

CN109869327B - Centrifugal compressor using static and dynamic pressure mixed gas thrust bearing

Info

Publication number: CN109869327B
Application number: CN201910089214.3A
Authority: CN
Inventors: 赵远扬; 唐斌; 杨启超; 刘广彬; 李连生
Original assignee: Qingdao University of Science and Technology
Current assignee: Anhui run'an Sibian Energy Technology Co.,Ltd.
Priority date: 2019-01-30
Filing date: 2019-01-30
Publication date: 2020-11-17
Anticipated expiration: 2039-01-30
Also published as: CN109869327A

Abstract

The invention discloses a centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing, which relates to the technical field of centrifugal compressor design and comprises a shell: a stator; a rotor; a thrust plate; the pair of thrust bearings are positioned on two sides of the thrust disc, a boss B and a wave foil B are arranged on one opposite side of each thrust bearing, the boss B and the wave foil B are arranged along the radial direction of each thrust bearing, the wave foils B are arranged on two sides of the boss B, a top foil B is arranged above the wave foil B, and the height of the boss B is lower than the height of the working surface of the top foil B; the side surface of the thrust bearing is provided with a channel B, the boss B is provided with a through hole B communicated with the channel B, and the shell is provided with an air supply channel communicated with the channel B. The thrust bearing has the beneficial effects that through the matching use of the static and dynamic pressure thrust bearing, the friction and the abrasion between the top foil of the dynamic pressure bearing and the thrust disc in the starting and stopping process and the axial load increasing process of the compressor can be reduced, and the service life of the compressor is prolonged; effectively improve the pressure of the bearing working face and improve the bearing capacity.

Description

Centrifugal compressor using static and dynamic pressure mixed gas thrust bearing

Technical Field

The invention relates to the technical field of centrifugal compressor design, in particular to a centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing.

Background

High rotational speed is the main technical approach for the miniaturization development of centrifugal compressors. The traditional oil lubrication rolling bearing and sliding bearing can not operate at ultra high speed due to the limitation of the structure and principle of the traditional oil lubrication rolling bearing and sliding bearing. This is one of the major technical bottlenecks in the miniaturization of centrifugal compressors.

The gas bearing has the advantages of stable operation at high speed, low energy consumption and the like, and is a core technology for realizing high speed of the centrifugal compressor. In recent years, gas thrust bearing technology has gradually begun to be applied to centrifugal compressors. The gas bearing includes a static pressure gas bearing and a dynamic pressure gas bearing. The static pressure gas bearing has stable starting and stopping process and large bearing capacity, but has poor stability (air hammer) at high speed and needs stable external gas supply; the dynamic pressure gas bearing has high stability under a high-speed working condition, does not need external gas supply, but can cause damage to the surface of the bearing in the starting and stopping process, has certain starting and stopping frequency limitation, and influences the use of the compressor. When the working condition of the centrifugal press changes, the axial force of the centrifugal press is increased suddenly, so that the thrust bearing is damaged, and finally the compressor is stopped due to failure.

The existing static pressure gas bearing needs high pressure gas supplied from the outside, and the matching equipment is complex and high in cost. The existing hydrodynamic gas bearing has the collision and abrasion phenomenon in the starting and stopping process, has high requirements on the frictional wear performance of the material of the bearing, and finally influences the service life of the bearing. When the centrifugal compressor is in a variable working condition, the axial load is increased, and the bearing capacity of the dynamic pressure gas thrust bearing is low, so that the effect of balancing the axial load cannot be well achieved.

Disclosure of Invention

The invention aims to increase a gas static pressure bearing, reduce bearing friction and prolong the service life of the bearing, and designs a centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing.

In order to achieve the above object, according to an aspect of the present invention, a centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing includes a housing, and further includes: a stator disposed within the housing; the rotor is rotatably arranged in the shell and corresponds to the stator; a thrust plate disposed on the rotor; the pair of thrust bearings are arranged in the shell and positioned on two sides of the thrust disc, a boss B and a wave foil B are arranged on one opposite side of each thrust bearing, the boss B and the wave foil B are arranged along the radial direction of each thrust bearing, the wave foil B is arranged on two sides of the boss B, a top foil B is arranged above the wave foil B, and the height of the boss B is lower than the height of the working surface of the top foil B; the side of the thrust bearing is provided with a channel B, the boss B is provided with a through hole B communicated with the channel B, and the shell is provided with an air supply channel communicated with the channel B.

Further, the number of the bosses B is eight, and the number of the bump foils B is eight.

Further, the surface of the boss B is coated with a lubricating layer.

Furthermore, the side surface of the thrust bearing is provided with an annular groove.

Still further, the shell is including casing, first support, casing, second support and the apron that sets gradually, footstep bearing sets up between apron and second support, be equipped with the air feed channel on the second support.

Further, still include journal bearing, journal bearing fixed set up in the shell, journal bearing's inner circle is equipped with boss A and ripples paper tinsel A, ripples paper tinsel A sets up the both sides at boss A, the top of ripples paper tinsel A is equipped with top paper tinsel A, boss A's highly be less than top paper tinsel A's working face height, be equipped with the through-hole A who runs through journal bearing on the boss A, be equipped with the same air feed channel with through-hole A on the shell.

Further, the number of the bosses a is two, and the number of the bump foils a is three.

Further, the surface of the boss A is coated with a lubricating layer.

Furthermore, a counter bore is arranged on the outer side of the through hole A.

Further, the number of the radial bearings is two, and the radial bearings are respectively arranged at two ends of the rotor.

Still further, the shell is including casing, first support, casing, second support and the apron that sets gradually, journal bearing sets up on first support, the stator fixed set up in on the casing, be equipped with air feed channel on first support and the second support.

The invention has the beneficial effects that: by the matching use of the static and dynamic pressure thrust bearing, the friction and the abrasion between the dynamic pressure bearing top foil and the thrust disc in the starting and stopping process and the axial load increasing process of the compressor can be reduced, and the service life of the compressor is prolonged; the pressure of the bearing working surface can be effectively improved, and the bearing capacity is improved.

Drawings

FIG. 1 is a schematic diagram of a compressor according to the present application;

FIG. 2 is a schematic view of the radial bearing of the present application;

FIG. 3 is an enlarged partial schematic view at A in FIG. 2;

FIG. 4 is a cross-sectional structural view of the journal bearing;

FIG. 5 is a schematic structural view of a thrust plate of the present application;

FIG. 6 is a schematic front view of the structure of FIG. 5;

FIG. 7 is a schematic left side view of the structure of FIG. 6;

FIG. 8 is a schematic cross-sectional view at B-B in FIG. 6;

fig. 9 is a partially enlarged schematic view at C in fig. 7.

In the above figures, 1, a housing; 10. a gas supply channel; 11. a housing; 12. a first bracket; 13. a housing; 14. a second bracket; 15. a cover plate; 2. a radial bearing; 21. a boss A; 22. a bump foil A; 23. a top foil A; 24. a through hole A; 3. a stator; 4. a rotor; 5. a thrust plate; 6. a thrust bearing; 61. a boss B; 62. a bump foil B; 63. a top foil B; 64. a channel B; 65. and a through hole B.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the embodiments, structures, features and effects according to the present invention with reference to the accompanying drawings and preferred embodiments is as follows:

a centrifugal compressor using a static-dynamic pressure hybrid radial gas bearing, as shown in fig. 1 to 9, includes a housing 1, a radial bearing 2, a stator 3, and a rotor 4.

As shown in fig. 2 to 4, the radial bearings 2 are fixedly provided in the housing 1, the number of the radial bearings 2 is two, and the radial bearings 2 are provided at both ends of the rotor 4, respectively. The inner ring of the radial bearing 2 is provided with a boss A21 and a wave foil A22, the wave foil A22 is arranged on two sides of the boss A21, a top foil A23 is arranged above the wave foil A22, and the height of the boss A21 is lower than the height of the working surface of the top foil A23, so that the boss A21 is prevented from contacting with the shaft of the rotor 4 in normal operation. The boss a21 is provided with a through hole a24 penetrating the radial bearing 2, the housing 1 is provided with a gas supply passage 10 corresponding to the through hole a24, and gas or liquid can be injected into the housing 1 from the gas supply passage 10 through the through hole a 24. For convenience of use, a counter bore may be provided at the outer side of the through hole a 24. In the figure, the number of the bosses a21 is two, and the number of the bump foils a22 is three, so that the input rate of gas or liquid is increased. Preferably, the surfaces of the boss A21 and the top foil A23 are coated with a lubricating layer to avoid surface damage during contact friction.

As shown in fig. 1, the stator 3 is disposed inside the housing 1. A rotor 4 is rotatably disposed within the radial bearing 2, the rotor 4 corresponding to the stator 3.

The housing 1 is mainly used for mounting. Regarding the structure of the housing 1, the present application provides a design solution, and the housing 1 includes a housing 11, a first bracket 12, a casing 13, a second bracket 14, and a cover plate 15, which are sequentially disposed. The radial bearing 2 is arranged on the first support 12, the stator 3 is fixedly arranged on the casing 13, and the first support 12 and the second support 14 are provided with air supply channels 10.

As shown in fig. 1, 5 to 9, a thrust disk 5 is provided on the rotor 4 for providing an axial force of the rotor 4. A pair of thrust bearings 6 are provided in the housing 1, the two thrust bearings 6 being located on either side of the thrust plate 5. The opposite side of the thrust bearing 6 is provided with a boss B61 and a wave foil B62, the boss B61 and the wave foil B62 are arranged along the radial direction of the thrust bearing 6, the wave foil B62 is arranged on the two sides of the boss B61, a top foil B63 is arranged above the wave foil B62, the height of the boss B61 is lower than the height of the working surface of the top foil B63, and the boss B61 is prevented from contacting with the side surface of the thrust disc 5 in normal operation. The side of the thrust bearing 6 is provided with a channel B64, the boss B61 is provided with a through hole B65 communicated with the channel B64, the shell 1 is provided with an air supply channel 10 communicated with the channel B64, and gas or liquid can be injected into the shell 1 from the air supply channel 10 through the channel B64 and the through hole B65. For convenience of use, an annular groove may be provided in the side surface of the thrust bearing 6, and the through hole B65 is provided in the annular groove. In the figure, the number of the bosses B61 is eight, and the number of the bump foils B62 is eight, so that the input rate of gas or liquid is increased. Preferably, the surfaces of the boss B61 and the top foil B63 are coated with a lubricating layer to avoid surface damage during contact friction. The thrust bearing 6 is arranged between the cover plate 15 and the second bracket 14, and the second bracket 14 is provided with the gas supply passage 10.

Before the compressor is started, high-pressure gas or liquid is supplied to the gas supply passage 10 of the compressor through an external gas supply device, and the high-pressure gas or liquid enters a gap between the rotor 4 and the radial bearing 2 through a through hole a24 formed in a boss a21, so that the rotor 4 is suspended in the radial bearing 2. The compressor is then started, with a progressive increase in the speed of rotation of the levitating rotor 4, whose dynamic pressure effect develops, the starting process of which is a hydrostatic bearing, when the rotor 4 can be levitated by the force generated by the radial bearing 2. And the external high-pressure gas or liquid supply is cut off, so that the compressor can stably work under the state that only the gas dynamic pressure bearing exists, namely the compressor is switched to the dynamic pressure bearing after stably running.

When the compressor load is increased and the dynamic pressure bearing can not meet the requirement of stable operation of the compressor, the load capacity of the bearing can be improved by supplying air to the radial bearing 2. When the compressor needs to be stopped, an external high-pressure gas or liquid channel is firstly opened to ensure that the bearing has enough bearing capacity, and then the rotating speed of the compressor is gradually reduced to stop.

When the axial load of the compressor is increased, high-pressure gas or liquid is supplied to the gas supply passage 10 by the external gas supply means, and the high-pressure gas or liquid enters the gap between the thrust disk 5 and the thrust bearing 6 through the passage B64 and the through hole B65, thereby balancing the axial load of the compressor.

The invention has been described above with reference to a preferred embodiment, but the scope of protection of the invention is not limited thereto, and various modifications can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention, and features mentioned in the various embodiments can be combined in any way as long as there is no structural conflict, and any reference sign in the claims should not be construed as limiting the claim concerned, from which the embodiment is to be regarded as being exemplary and non-limiting in any way. Therefore, all technical solutions that fall within the scope of the claims are within the scope of the present invention.

Claims

1. A centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing, comprising a casing (1), characterized by further comprising:

a stator (3) disposed within the housing (1); and

a rotor (4) rotatably disposed in the housing (1) and corresponding to the stator (3);

a thrust disk (5) disposed on the rotor (4); and

the thrust bearings (6) are arranged in the shell (1) and located on two sides of the thrust disc (5), a boss B (61) and a wave foil B (62) are arranged on one opposite side of each thrust bearing (6), the boss B (61) and the wave foil B (62) are arranged along the radial direction of each thrust bearing (6), the wave foil B (62) is arranged on two sides of the boss B (61), a top foil B (63) is arranged above each wave foil B (62), and the height of each boss B (61) is lower than the height of the working surface of the corresponding top foil B (63); the side of thrust bearing (6) is equipped with passageway B (64), be equipped with through-hole B (65) with passageway B (64) intercommunication on boss B (61), be equipped with on shell (1) with the communicating air feed passageway (10) of passageway B (64).

2. The centrifugal compressor using static-dynamic pressure mixed gas thrust bearing according to claim 1, wherein the number of bosses B (61) is eight, and the number of bump foils B (62) is eight.

3. The centrifugal compressor using the static-dynamic pressure mixed gas thrust bearing according to claim 1, wherein the surface of the boss B (61) is coated with a lubricating layer.

4. A centrifugal compressor using a static-dynamic pressure mixed gas thrust bearing according to claim 1, characterized in that the thrust bearing (6) is provided with an annular groove on its side.

5. The centrifugal compressor using the static-dynamic pressure mixed gas thrust bearing according to claim 4, wherein the housing (1) comprises a shell (11), a first bracket (12), a casing (13), a second bracket (14) and a cover plate (15) which are arranged in sequence, the thrust bearing (6) is arranged between the cover plate (15) and the second bracket (14), and the second bracket (14) is provided with a gas supply channel (10).