CN217713373U

CN217713373U - Rotor system and gas turbine

Info

Publication number: CN217713373U
Application number: CN202221785313.9U
Authority: CN
Inventors: 段萌珠
Original assignee: Xingchen Mengxiang Technology Beijing Co ltd
Current assignee: Xingchen Mengxiang Technology Beijing Co ltd
Priority date: 2022-07-08
Filing date: 2022-07-08
Publication date: 2022-11-01
Anticipated expiration: 2032-07-08

Abstract

The utility model discloses a rotor system, which comprises a rotating shaft and a radial mixed bearing, wherein the radial mixed bearing comprises a buffer bearing, a radial air bearing and a fastening component, wherein the buffer bearing is fixedly sleeved on the rotating shaft, the radial air bearing is sleeved outside the buffer bearing, and a gap is arranged between the radial air bearing and the outer wall of the buffer bearing; the buffer bearing comprises two rolling bearings and a fixing piece, the two rolling bearings are axially arranged in parallel, the fixing piece is respectively and fixedly connected with outer rings of the two rolling bearings, and inner rings of the two rolling bearings are sleeved on the rotating shaft; the fastening assembly is fixedly sleeved on the rotating shaft and abuts against two sides of the buffer bearing. The utility model also discloses a gas turbine including this rotor system. The utility model discloses set up buffer bearing between pivot and air bearing, utilize buffer bearing not only can bear the characteristic of radial force but also can bear the axial force, can effectively protect rotor system's structure and stability, prolong its life.

Description

Rotor system and gas turbine

Technical Field

The utility model relates to a rotor system and gas turbine belongs to heat engine technical field.

Background

The gas turbine uses continuous flowing gas as working medium to drive the impeller to rotate at high speed, and converts the energy of fuel into useful work, and is a rotary impeller type heat engine, which mainly comprises three parts of a gas compressor, a combustion chamber and a turbine: the air compressor sucks air from the external atmospheric environment, compresses the air to pressurize the air, and simultaneously, the air temperature is correspondingly increased; compressed air is pumped into a combustion chamber and is mixed with injected fuel to be combusted to generate high-temperature and high-pressure gas; then the gas or liquid fuel enters a turbine to do work through expansion, the turbine is pushed to drive a gas compressor (and an external load rotor) to rotate at a high speed, the chemical energy of the gas or liquid fuel can be partially converted into mechanical work and heat energy, and the mechanical work and the heat energy can be output through connecting a generator.

Non-contact bearings (e.g., gas bearings) are increasingly used in high-speed applications due to their low friction coefficient and torque, high motion accuracy, and other characteristics. The gas bearing relies on a pressurized gas film in the bearing gap to support the rotor system. The gas bearing may be applied to a gas turbine. However, according to the principle of the gas bearing, in the start-stop stage, the rotation state of the rotating shaft is unstable (the rotation state is also unstable due to gas fluctuation and the like), the rotating shaft is inclined relative to the axis of the gas bearing, and collides or rubs against the inner wall of the gas bearing, which is likely to cause damage to the structure of the rotor system and a reduction in the service life of the rotor system, and is not favorable for maintaining the stability of the rotor system.

Disclosure of Invention

To the above-mentioned prior art, the utility model provides a rotor system, the utility model discloses set up the buffering bearing between pivot and air bearing, utilize the buffering bearing not only can bear the characteristic of radial force but also can bear the axial force, protect rotor system's structure and stability, prolong its life. The utility model discloses still provide the gas turbine including this rotor system.

The application provides a rotor system, this rotor system includes pivot and radial hybrid bearing, and radial hybrid bearing includes buffer bearing, radial air bearing and fastening components. The buffer bearing comprises two rolling bearings and a fixing piece, the two rolling bearings are axially and fixedly sleeved on the rotating shaft in parallel, the fixing piece is respectively and fixedly connected with outer rings of the two rolling bearings, and the rolling bearings are bearings capable of bearing radial force and axial force. The radial air bearing is sleeved outside the buffer bearing and has a gap with the outer wall of the buffer bearing. The fastening assembly is fixedly sleeved on the rotating shaft and abuts against two sides of the buffer bearing, and acting force is applied to two end faces of the buffer bearing inwards.

Further, the pivot includes bearing installation section and pivot section, and the diameter of bearing installation section is less than the diameter of pivot section, buffering bearing cover is established on the bearing installation section.

Further, be provided with annular butt platform on the bearing installation section, one side butt annular butt platform of buffering bearing, opposite side butt fastening components.

Further, the fastening assembly comprises a first nut and a second nut, and the first nut and the second nut respectively abut against two sides of the buffer bearing.

Furthermore, an annular U-shaped groove is formed in the fixing piece, and the fixing piece is fixedly sleeved on the outer ring of the rolling bearing through the U-shaped groove.

Further, the fixing piece is welded to the outer rings of the two rolling bearings respectively, or the fixing piece and the outer rings of the two rolling bearings are integrally formed.

Furthermore, two radial hybrid bearings are arranged on the rotating shaft in parallel.

Further, the rolling bearing is an angular contact bearing, and the two angular contact bearings are arranged back to back, face to face or in series.

Further, the rotor system further comprises a thrust ball bearing and a thrust air bearing; a thrust disc is arranged on the rotating shaft, a thrust air bearing is sleeved outside the thrust disc, a seat ring of a thrust ball bearing is fixedly arranged on the stator, a shaft ring of the thrust ball bearing faces one side of the rotating shaft, one end of the rotating shaft is provided with a butting surface, and the shaft ring of the thrust ball bearing is opposite to the butting surface of the rotating shaft; when the thrust disc is located at the middle position of the thrust air bearing, the width of a gap between the thrust disc and the thrust air bearing is larger than that of a gap between the abutting surface and the shaft ring.

The present application further provides a gas turbine comprising the rotor system described above.

The rotor system of the utility model is provided with the buffer bearing on the rotating shaft, when the rotating shaft inclines, the buffer bearing replaces the rotating shaft to contact with the radial air bearing, the outer ring of the buffer bearing rotates, the sliding is changed into rolling, and the abrasion is reduced; meanwhile, the buffer bearing bears radial force and plays a role in buffering between the rotating shaft and the radial air bearing, and therefore the structure and the stability of the whole rotor system are protected. In addition, the fastening assemblies are adopted to clamp inwards from the two axial sides of the buffer bearing, the play of the two rolling bearings is reduced, the buffer bearing can not rotate or rotate at a very low speed when the rotor rotates at a high speed, the service life of the buffer bearing can be prolonged, the lubricating requirement of the buffer bearing is reduced, and common lubricating grease can be used or is not required to be used. Meanwhile, when the rotating shaft stably rotates at a high speed in the radial air bearing, if the outer ring of the buffer bearing rotates under the action of air friction force, a part of energy is consumed, so that the clearance of the buffer bearing is reduced, the energy loss is also reduced, and the overall thermal efficiency of the gas turbine is improved.

In addition, when the rotating shaft rotates, axial thrust is generated on the rotating shaft, however, when the thrust air bearing is started or stopped, especially when the thrust air bearing is a self-static pressure bearing, the gas in the thrust air bearing is not enough to resist the axial force, so that friction and collision occur between the thrust disc and the thrust air bearing, and further damage to the rotating shaft and the thrust air bearing is easily caused. Therefore, the utility model discloses set up thrust ball bearing in the one end of pivot, when thrust air bearing opened and stops, the pivot removed towards thrust ball bearing's direction, until butt thrust ball bearing's race. Because when the thrust dish was located thrust air bearing's intermediate position, the clearance width between thrust dish and the thrust air bearing was greater than the clearance width between butt face and the race, consequently the thrust dish did not contact with thrust air bearing this moment to sliding friction and collision between with thrust dish and the thrust air bearing convert thrust ball bearing's rolling friction, can effectively protect the structure of thrust air bearing and pivot.

The utility model discloses a rotor system sets up the buffer bearing between pivot and air bearing, utilizes the buffer bearing not only can bear the radial force but also can bear the characteristic of axial force, protects rotor system's structure and stability, prolongs its life. In addition, the thrust ball bearing is arranged to protect the thrust air bearing, so that the problem that a rotor system is unstable in a start-stop stage caused by the fact that the air bearing is used as the thrust bearing and the radial bearing is solved.

The various terms and phrases used herein have the ordinary meaning as is well known to those skilled in the art. To the extent that the terms and phrases are not inconsistent with a known meaning, the meaning of the present invention is expressed, the specification is set forth.

Drawings

FIG. 1: the structure of the rotor system is shown schematically.

Wherein, 1, a rotating shaft; 2. a radial hybrid bearing; 3. a buffer bearing; 4. a radial air bearing; 5. a fastening assembly; 6. a rolling bearing; 7. a fixing member; 8. an outer ring; 9. an inner ring; 10. a U-shaped groove; 11. a bearing mounting section; 12. a shaft section; 13. an annular abutment table; 14. a thrust ball bearing; 15. a thrust air bearing; 16. a thrust disc; 17. a seat ring; 18. a shaft ring; 19. an abutting surface; 20. a compressor; 21. a turbine.

Detailed Description

The present invention will be further described with reference to the following examples. However, the scope of the present invention is not limited to the following examples. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.

In a first aspect, the present application provides a rotor system, which includes a rotating shaft 1 and a radial hybrid bearing 2, wherein the radial hybrid bearing 2 includes a buffer bearing 3, a radial air bearing 4 and a fastening component 5, as shown in fig. 1, wherein the buffer bearing 3 is fixedly sleeved on the rotating shaft 1, and the radial air bearing 4 is sleeved outside the buffer bearing 3 and has a gap with an outer wall of the buffer bearing 3.

The buffer bearing 3 comprises two rolling bearings 6 and a fixing part 7, the two rolling bearings 6 are arranged in parallel in the axial direction, the fixing part 7 is respectively and fixedly connected with outer rings 8 of the two rolling bearings 6, and inner rings 9 of the two rolling bearings 6 are sleeved on the rotating shaft 1; the buffer bearing 3 can bear axial forces in two directions, so when the buffer bearing 3 replaces the rotating shaft 1 to be in contact with the radial air bearing 4, the buffer bearing 3 can bear the radial force and the axial forces in two directions simultaneously, the buffer can be realized from the radial direction and the axial direction, and the structure of a rotor system is effectively protected.

The fastening assembly 5 is fixedly sleeved on the rotating shaft 1, the fastening assembly 5 abuts against two sides of the buffer bearing 3, two rolling bearings 6 are abutted inwards from two axial sides of the buffer bearing 3, acting force is applied inwards to two end faces of the buffer bearing 3, and therefore the play of the buffer bearing 3 is reduced. Adopt fastening components 5 to inwards press from both sides from the axial of buffer bearing 3 and press from both sides tightly, reduce the play of two antifriction bearing 6, can make buffer bearing 3 not rotate or rotate with very little speed when the rotor is rotatory at a high speed, can prolong its life, reduce its lubricated requirement, use ordinary lubricating grease can, perhaps need not lubricate. Meanwhile, when the rotating shaft 1 stably rotates at a high speed in the radial air bearing 4, if the outer ring of the buffer bearing 3 rotates under the action of air friction force, a part of energy is consumed, so that the reduction of the play of the buffer bearing 3 can also reduce energy loss, and the overall thermal efficiency of the gas turbine is improved.

Alternatively, the rolling bearing 3 is a bearing that can withstand axial forces, such as a deep groove ball bearing, a tapered roller bearing, or an angular contact bearing, and preferably an angular contact bearing. When the rolling bearing 3 is an angular contact bearing, the two angular contact bearings may be arranged back to back, face to face, or in series.

Optionally, an annular U-shaped groove 10 is formed in the fixing member 7, and the fixing member 7 is fastened and sleeved on the outer ring 8 of the rolling bearing 6 through the U-shaped groove 10. The fixing piece can be welded to the outer ring 8 of the two rolling bearings 6, or: the fixing member 7 is integrally formed with the outer rings 8 of the two rolling bearings 6.

Optionally, the fastening assembly 5 comprises a first nut and a second nut, which abut against two sides of the cushion bearing 3, respectively.

In some embodiments, the rotating shaft may include a bearing installation section 11 and a rotating shaft section 12, the buffer bearing 3 is sleeved on the bearing installation section 11, the diameter of the bearing installation shaft section 11 is smaller than that of the rotating shaft section 12, so that the outer diameter of the buffer bearing 3 installed on the bearing installation section 11 is smaller than or equal to that of the rotating shaft section 12, the radial size of the buffer bearing 3 is not increased or reduced under the condition that the buffer bearing is additionally arranged in the rotor system, and the overall size of the rotor system and the gas turbine is favorably controlled.

In some embodiments, the bearing mounting section 11 is provided with an annular abutment 13, one side of the buffer bearing 3 abuts the annular abutment 13, and the other side abuts the fastening assembly 5, in which case the fastening assembly 5 may be a nut.

Alternatively, two radial hybrid bearings 2 may be arranged side by side on the rotating shaft 1. Specifically, when two radial air bearings 4 are provided on the rotating shaft 1, two buffer bearings 3 are correspondingly provided on the rotating shaft 1, that is, two radial hybrid bearings 2 are provided on the rotating shaft 1.

In a possible implementation manner, the rotor system may further include a thrust ball bearing 14 and a thrust air bearing 15, a thrust disc 16 is disposed on the rotating shaft 1, the thrust air bearing 15 is sleeved outside the thrust disc 16, a race 17 of the thrust ball bearing 14 is fixedly mounted on the stator 20, a race 18 of the thrust ball bearing 14 faces one side of the rotating shaft 1, one end of the rotating shaft 1 is provided with an abutting surface 19, a direction in which the thrust disc 16 points to the abutting surface 19 is the same as an axial thrust direction of the rotating shaft 1 under a maximum operating condition, and the race 18 of the thrust ball bearing 14 is opposite to the abutting surface 19 of the rotating shaft 1; when the thrust disk 16 is located at the intermediate position of the thrust air bearing 15, the gap width between the thrust disk 16 and the thrust air bearing 15 is larger than the gap width between the abutment surface 19 and the collar 18.

In the above implementation, when the rotating shaft 1 rotates, an axial thrust is generated on the rotating shaft 1, however, when the air thrust bearing 15 is started or stopped, especially when the air thrust bearing 15 is a self-hydrostatic bearing, the gas in the air thrust bearing 15 is not enough to resist the axial force, so that friction and collision occur between the thrust disc 16 and the air thrust bearing 15, and damage to the rotating shaft 1 and the air thrust bearing 15 is easily caused. Therefore, in the present embodiment, the thrust ball bearing 14 is provided at one end of the rotating shaft 1, and when the thrust air bearing 15 is started and stopped, the rotating shaft 1 moves toward the thrust ball bearing 14 until it abuts against the race 18 of the thrust ball bearing 14. Since the width of the gap between the thrust disk 16 and the thrust air bearing 15 is greater than the width of the gap between the abutting surface 19 and the collar 18 when the thrust disk 16 is located at the middle position of the thrust air bearing 15, the thrust disk 16 is not in contact with the thrust air bearing 15 at this time, so that the sliding friction and the collision between the thrust disk 16 and the thrust air bearing 15 are converted into the rolling friction of the thrust ball bearing 14, and the structure of the thrust air bearing 15 and the rotating shaft 1 can be effectively protected.

In a second aspect, the present application further provides a gas turbine, which includes the rotor system of the first aspect, and a compressor 21, a combustion chamber and a turbine 22, where the compressor 21 and the turbine 22 are both disposed on the rotating shaft 1, and the combustion chamber is connected to the compressor 21.

The above examples are provided to those of ordinary skill in the art to fully disclose and describe how to make and use the claimed embodiments, and are not intended to limit the scope of the disclosure herein. Modifications apparent to those skilled in the art are intended to be within the scope of the appended claims.

Claims

1. A rotor system, characterized by: including pivot and radial hybrid bearing, radial hybrid bearing includes:

the buffer bearing comprises two rolling bearings and a fixing part, the two rolling bearings are axially parallelly fixedly sleeved on the rotating shaft, the fixing part is respectively and fixedly connected with outer rings of the two rolling bearings, and the rolling bearings are bearings capable of bearing radial force and axial force;

the radial air bearing is sleeved outside the buffer bearing, and a gap is formed between the radial air bearing and the outer wall of the buffer bearing;

and the fastening assembly is fixedly sleeved on the rotating shaft and is abutted against two sides of the buffer bearing, and acting force is exerted inwards on two end faces of the buffer bearing.

2. The rotor system of claim 1, wherein: the pivot includes bearing installation section and pivot section, and the diameter of bearing installation section is less than the diameter of pivot section, the buffering bearing housing is established on the bearing installation section.

3. The rotor system of claim 2, wherein: the bearing mounting section is provided with an annular butt joint table, one side of the buffer bearing is abutted to the annular butt joint table, and the other side of the buffer bearing is abutted to the fastening assembly.

4. The rotor system of claim 1, wherein: the fastening assembly comprises a first nut and a second nut, and the first nut and the second nut are respectively abutted against two sides of the buffer bearing.

5. The rotor system of claim 1, wherein: the fixing piece is provided with an annular U-shaped groove, and the fixing piece is fixedly sleeved on the outer ring of the rolling bearing through the U-shaped groove.

6. The rotor system of claim 1, wherein: the fixing piece is welded to the outer rings of the two rolling bearings respectively, or the fixing piece and the outer rings of the two rolling bearings are integrally formed.

7. The rotor system of claim 1, wherein: two radial mixed bearings are arranged on the rotating shaft in parallel.

8. The rotor system of claim 1, wherein: the rolling bearing is an angular contact bearing, and the two angular contact bearings are arranged back to back, face to face or in series.

9. The rotor system according to any one of claims 1-8, wherein: the device also comprises a thrust ball bearing and a thrust air bearing; a thrust disc is arranged on the rotating shaft, a thrust air bearing is sleeved outside the thrust disc, a seat ring of a thrust ball bearing is fixedly arranged on the stator, a shaft ring of the thrust ball bearing faces one side of the rotating shaft, one end of the rotating shaft is provided with a butting surface, and the shaft ring of the thrust ball bearing is opposite to the butting surface of the rotating shaft; when the thrust disc is located at the middle position of the thrust air bearing, the width of a gap between the thrust disc and the thrust air bearing is larger than that of a gap between the abutting surface and the shaft ring.

10. A gas turbine, characterized by: comprising a rotor system according to any of claims 1-9.