CN108608015B

CN108608015B - Air turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system

Info

Publication number: CN108608015B
Application number: CN201810366695.3A
Authority: CN
Inventors: 梁国柱; 杜家磊; 闫攀运
Original assignee: Beihang University
Current assignee: Beihang University
Priority date: 2018-04-23
Filing date: 2018-04-23
Publication date: 2020-04-10
Anticipated expiration: 2038-04-23
Also published as: CN108608015A

Abstract

The invention provides a gas turbine driven high-speed water lubrication hybrid bearing rotor system, which comprises a main shaft, a pneumatic turbine, a turbine gas nozzle ring, a gas thrust bearing, a water lubrication hybrid radial bearing, a shell and an end cover, wherein the main shaft is connected with the gas turbine; during assembly, a turbine gas nozzle ring is installed in a shell, then an integrated rotor part formed by interference fit of a pneumatic turbine and a main shaft is installed, then a gas thrust bearing and a water-lubricated hybrid radial bearing are sequentially installed on two sides of the turbine respectively, and finally end covers are installed at two ends of the shell; the turbine gas nozzle ring, the gas thrust bearing and the water lubrication dynamic and static pressure radial bearing are in interference fit with the shell. The pneumatic turbine integrated with the main shaft is adopted as the driving device, so that the pneumatic turbine has the advantages of simple structure and high rotating speed; the water lubrication hybrid bearing is used as a supporting part, and has the advantages of small temperature rise of a lubricating medium and capability of realizing high rotating speed; the whole bearing rotor system has the characteristics of simple and compact structure.

Description

Air turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system

Technical Field

The invention belongs to the field of liquid hybrid bearings and high-speed rotating mechanical equipment, and particularly relates to a rotor system of a gas turbine driven high-speed water lubricated hybrid bearing.

Background

With the development of rotating machinery toward higher speeds, the DN value (product of the main shaft bearing diameter D/mm and the rotation speed N/rpm) and the problem of wear of the conventional rolling bearing limit the increase in the rotation speed of the rotor. Although the oil lubrication hydrostatic bearing widely applied in machine tool equipment can reach higher rotating speed, the problem caused by temperature rise of lubricating oil is more and more serious along with further increase of the rotating speed of a rotor due to higher viscosity of oil. Therefore, bearing rotor systems with high rotational speeds have become a focus of research.

From the perspective of the supporting structure, the bearings currently used in the high-speed bearing rotor system mainly include ceramic ball bearings, air bearings, magnetic suspension bearings, liquid hydrostatic bearings, and the like. The ceramic ball bearing has the advantages of high rigidity and large bearing capacity, but the precision requirement of the bearing ball is high, the processing cost is high, and the service life is only thousands of hours; the air bearing has small friction resistance in normal work, can realize ultra-high speed operation, but has small bearing capacity and low rigidity, and is mainly used for a tiny precise main shaft unit; the electric spindle supported by the magnetic suspension bearing can work for a long time at the rotating speed of 50000-80000 rpm, but the supporting rigidity is low, the structure is complex, and the manufacturing cost is high.

Compared with the bearings, the liquid hybrid bearing has the following advantages: the liquid dynamic and static pressure bearing supplies a lubricating medium with certain pressure into a concave cavity of the bearing by using a supply system, a lubricating liquid film is formed in a gap between a shaft neck and the bearing, a sliding surface is completely separated by the lubricating medium, and the friction force of the sliding surface is only the internal shearing force of the lubricating medium, so the friction resistance is very small; the error homogenization and vibration resistance of the lubricating liquid film can ensure the high precision and running stability of the main shaft; there is no theoretical life limit due to no direct rigid body contact; the bearing utilizes the pressure difference between the concave cavities to form bearing capacity to float the main shaft, and has the characteristic of high rigidity; and due to the external pressure supply device, the bearing can provide reliable support for the rotor within the full working rotating speed range.

Based on the advantages of the liquid dynamic and static pressure bearing, the oil lubrication liquid dynamic and static pressure bearing is widely applied to common machine tool equipment. However, in high-speed machine tools, as the rotation speed is further increased, the viscous shear force between lubricant films is increased, the friction power consumption is increased, the temperature rise of a lubricant is high, the thermal deformation of a bearing rotor structure is caused, the precision of a spindle is slightly affected, and accidents such as shaft sticking are caused. And if water is adopted as a lubricating medium of the hybrid bearing, the problem of temperature rise can be better solved. Compared with lubricating oil, water has the characteristics of low viscosity, small frictional resistance and large specific heat capacity, and the problem of temperature rise at high speed can be obviously improved by adopting water as a lubricating medium, which can be seen in a reference document [1 ]; and the water has the advantages of wide source, low cost, no pollution and the like, and is a lubricating medium with development prospect. The water lubricated bearing has related application research at home and abroad, but due to different application backgrounds, related research results are also characterized.

From the viewpoint of driving structure, the driving methods adopted by the high-speed rotor bearing system mainly include motor driving, electric spindle driving, turbine driving and the like. The motor drive is to connect the output shaft of the motor with the main shaft through a transmission structure, but is limited by the rotating speed of the motor, and sometimes to reach higher rotating speed, parts such as a coupler, a transmission and the like are usually used in the transmission structure, so that the whole system is huge. The electric main shaft is a new technology which integrates a working main shaft and a motor rotor into a whole and appears in recent years, a complex intermediate transmission part is omitted, zero transmission is realized, a mechanical structure is simplified, and the electric main shaft is a driving structure with a wide development prospect and can be seen in a reference document [2 ]; the main defect is that the electric spindle can generate a large amount of heat at high speed to cause temperature rise of the electric spindle, so that the thermal state characteristic and the dynamic characteristic of the electric spindle are deteriorated, and the normal work of the electric spindle is influenced.

Compared with motor drive and electric spindle drive, the air turbine drive has the advantages of simple structure and low cost, so the air turbine drive is also a drive mode widely adopted in rotary equipment. Most of the existing gas turbine driving bearing rotor systems adopt rolling bearings as supporting parts, so that the friction resistance is high, and the rotor cannot reach a high rotating speed easily.

Reference document [1] Chenwei, Fanghongjie, Wulianjun. research review on water-lubricated high-speed spindle bearings [ J ] Chinese engineering science, 2013,15(1): 21-27.

Reference document [2] bear Wanli, Yangxueng, Lulang, etc. summary of key technologies of liquid dynamic and static piezoelectric spindles [ J ] mechanical engineering report, 2009,45(9): 1-18.

Disclosure of Invention

Based on the problems that the system which is required to be realized by the existing motor drive for achieving higher rotating speed is larger, the electric spindle drive can generate a large amount of heat at high speed to influence the normal work of the electric spindle, and the DN value of the rolling bearing limits the further improvement of the rotating speed of the rotor, the invention provides a gas turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system which is suitable for high-speed rotating equipment, and the maximum rotating speed of the rotor can reach 55000 rpm.

The invention relates to a gas turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system, which comprises: the device comprises a main shaft, a pneumatic turbine, a turbine gas nozzle ring, a water-lubricated dynamic and static pressure radial bearing, a gas thrust bearing, a shell and an end cover. During assembly, a turbine gas nozzle ring is installed in a shell, then an integrated rotor part formed by interference fit of a pneumatic turbine and a main shaft is installed, then a gas thrust bearing and a water-lubricated hybrid radial bearing are sequentially installed on two sides of the turbine respectively, and finally end covers are installed at two ends of the shell, and the correct positions and directions of gas path runners and water path runners at each position are ensured; the turbine gas nozzle ring, the gas thrust bearing and the water-lubricated dynamic and static pressure radial bearing are in interference fit with the shell; in the installation process, all parts are ensured to be installed in place so as to ensure that the thrust clearance of the thrust bearing and the radial clearance of the radial bearing meet the design requirements.

The pneumatic turbine is a double-row impulse turbine consisting of a turbine disc and radial turbine blades, the outer end surfaces of two sides of the pneumatic turbine are designed to be used as thrust surfaces of an air thrust bearing, and exhaust grooves are reserved on two axial sides of the turbine blades, are exhaust channels of low-pressure gas of the turbine and are also used as one of the exhaust channels of the air thrust bearing; the driving gas of the pneumatic turbine is air or nitrogen.

The turbine gas nozzle ring is provided with two rows of nozzles, each row of nozzles consists of a plurality of gas nozzles which are uniformly distributed in the circumferential direction and are arranged along the tangential direction, and the two rows of nozzles respectively correspond to two rows of turbine blades on the pneumatic turbine; an air inlet groove is reserved on the outer circle surface of the nozzle ring and is communicated with a turbine air inlet hole in the shell, high-pressure driving air enters the air inlet groove from the turbine air inlet hole, and the high-pressure driving air drives the turbine blades to rotate after being expanded and accelerated by the nozzle. And the axial dimension of the nozzle ring can be used to control the size of the thrust gap of the thrust bearing.

The gas thrust bearing is a gas static pressure bearing and is used for controlling the axial movement of the rotor, an annular groove is formed in the outer circle surface of the thrust bearing, and the annular groove is in interference fit with the shell to form a gas flow equalizing groove and is communicated with a thrust bearing air inlet on the shell to form an air supply channel of the gas thrust bearing.

The water lubrication hybrid bearing is a supporting part of a rotor, 4 concave cavities are uniformly distributed on the inner circle surface of the bearing along the circumferential direction, the edge of each concave cavity along the axial direction is designed into a circular arc transition convenient to process, an annular groove is processed on the outer circle surface of the bearing, and each concave cavity is communicated with the annular groove through a throttling hole; the annular groove on the surface of the excircle of the bearing is in interference fit with the shell to form a water equalizing groove and is communicated with a dynamic and static pressure bearing water inlet hole on the shell; the external system supplies water with certain pressure to enter the flow equalizing groove from the hydrostatic bearing water inlet hole, flows into the concave cavity through the throttling hole, and then flows into the gap between the journal and the bearing to form a water lubricating liquid film to provide bearing capacity for the rotor.

The casing be integrated structure, open on the casing and have hybrid bearing inlet opening, turbine inlet port and footstep bearing inlet port, 3 holes respectively with the ring channel of water lubrication hybrid radial bearing, the inlet channel of turbine gas nozzle ring and the ring channel of gas footstep bearing, constitute 3 independent water or air feed channels, 3 channels coexist on the casing and do not interfere with each other.

The casing, through punching along the axial at the casing wall to and the interference fit between water lubrication hybrid bearing, gaseous footstep bearing and the casing, with the fluid-equalizing groove intercommunication of hybrid bearing inlet opening and two water lubrication hybrid radial bearings, with the footstep bearing inlet port and the fluid-equalizing groove intercommunication of two gaseous footstep bearings.

A water outlet is formed below the shell and used for collecting water discharged by the dynamic and static pressure bearing; sensor mounting holes are reserved on the upper surface and the side surface of the shell, which are close to the end surfaces of the radial bearings, and displacement sensors can be mounted to measure the vibration of the rotor in the horizontal and vertical directions at the two radial bearings so as to monitor the working condition of the rotor system.

The end cover is used for limiting the axial movement of the water lubrication dynamic and static pressure radial bearing and the gas thrust bearing in the shell, and a positioning pin can be arranged on the side surface of the end cover to prevent the rotation of the water lubrication dynamic and static pressure radial bearing; the end cover is in radial fit with the main shaft and is sealed by a gap, so that the leakage of water at the end cover is reduced.

Compared with the prior art, the invention has the advantages that:

(1) the invention adopts the pneumatic turbine as the driving device of the main shaft, the pneumatic turbine has the advantages of no pollution, variable rotating speed and high rotating speed, the rotating speed of the rotor can reach 55000rpm, and the problems of complex transmission structure and large heat productivity of the electric main shaft in the motor driving are solved;

(2) the pneumatic turbine and the main shaft are assembled into an integrated component in an interference manner, the dynamic balance is good, the structure is simple, components such as a coupler are not needed, and the installation and the positioning are convenient;

(3) the adopted gas thrust bearing is a hydrostatic bearing, can provide enough thrust within the full working rotating speed range, has no direct contact and abrasion between the rotor and other parts in normal work, and improves the high-speed performance and the service life of a bearing rotor system;

(4) the water lubrication dynamic and static pressure radial bearing is adopted as a bearing part of the bearing rotor system, and has the characteristics of high rigidity, high precision and good stability; the bearing uses water as a working medium, the temperature rise of a lubricating medium is small during working, the high-speed performance is good, and the water lubrication has the advantages of low cost, low friction power consumption and no pollution;

(5) the shell of the bearing rotor system is an integrally processed component, is a supporting structure of the bearing rotor system, can ensure that the two water-lubricated dynamic and static pressure radial bearings have high coaxiality after being installed, and has high installation precision;

(6) the water supply channels of the two water lubrication hybrid radial bearings, the two gas thrust bearings and the gas supply channel of the pneumatic turbine coexist in the shell through reasonable structure and assembly design, are not interfered with each other, and have small integral size and compact structure.

Drawings

FIG. 1 is a schematic view of the overall structure of a rotor system of a high-speed water-lubricated hybrid bearing driven by an air turbine according to the invention;

FIG. 2 is a schematic view of an integrated rotor structure of a pneumatic turbine and a main shaft of the bearing rotor system of the present invention;

FIG. 3 is a schematic structural view of a turbine gas nozzle ring of the bearing rotor system of the present invention;

FIG. 4 is a schematic structural view of a water lubricated hybrid radial bearing of the bearing rotor system of the present invention;

FIG. 5 is a schematic view of the gas thrust bearing of the bearing rotor system of the present invention;

FIG. 6 is a schematic structural view of a housing of the bearing rotor system of the present invention;

FIG. 7 is a schematic structural view of an end cover of the bearing rotor system of the present invention.

In the figure:

a-the pneumatic turbine and the main shaft integrated rotor; a 01-impulse turbine blade; a02-turbine exhaust groove; a 03-thrust face; b-a turbine gas nozzle ring; b01-gas nozzle; b02-air inlet groove; b03-vent hole;

a C-gas thrust bearing; c01-annular groove of gas thrust bearing; c02-orifice of gas thrust bearing;

d-water lubrication of the dynamic and static pressure radial bearing; d01-annular groove of water lubricated hybrid radial bearing;

d02-orifice of water lubricated hybrid radial bearing; d03-cavity;

e-a housing; e01-dynamic and static pressure bearing water inlet; e02-turbine intake; e03-thrust bearing intake hole;

e04-vent; e05-sensor mounting holes; e06-drainage port;

f-end cover; f01-locating holes; f02-gap seal groove.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

The invention provides a gas turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system, which adopts an integrated pneumatic turbine matched with a main shaft as a driving device and has the advantages of simple structure and high rotating speed; the water lubrication hybrid bearing is used as a supporting part, so that the bearing has the advantages of small temperature rise and high rotating speed; the whole bearing rotor system has the characteristics of simple and compact structure.

The invention relates to a gas turbine driven high-speed water lubrication dynamic and static pressure bearing rotor system, as shown in figure 1, mainly comprising: the turbine and main shaft integrated rotor A, a turbine gas nozzle ring B, a gas thrust bearing C, a water lubrication dynamic and static pressure radial bearing D, a shell E and an end cover F. In the assembling process, a turbine gas nozzle ring B is installed in a shell E, then a turbine and main shaft integrated rotor A is installed, a gas thrust bearing C and a water lubrication dynamic and static pressure radial bearing D are sequentially installed on two sides of the turbine respectively, and finally end covers F on two sides are installed. The turbine gas nozzle ring B, the gas thrust bearing C and the water lubrication dynamic and static pressure radial bearing D are in interference fit with the shell E.

As shown in fig. 2, the turbine and main shaft integrated rotor a is an integrated structure formed by interference fit of the turbine and the main shaft. The pneumatic turbine is an impulse turbine. Considering the processing problem of the turbine, the impulse turbine blade a01 can adopt a circular arc blade; in order to increase the output power, the turbine blades are designed into two rows, and exhaust grooves A02 are reserved on two axial sides of each row of turbine blades; meanwhile, the outer end faces of two sides of the turbine are designed to be thrust faces A03 of the gas thrust bearing C, so that the whole structure is more compact, and the turbine exhaust groove A02 also serves as one of exhaust passages of the gas thrust bearing C. The driving gas of the pneumatic turbine is air or nitrogen.

As shown in fig. 3, the turbine gas nozzle ring B is provided with two rows of nozzles, each row is composed of a plurality of tangential gas nozzles B01 uniformly distributed in the circumferential direction, and the two rows of nozzles respectively correspond to two rows of turbine blades; in order to simplify the structure, the turbine gas nozzle ring B and the shell E are in interference fit. An air inlet groove B02 is reserved on the outer surface of the turbine gas nozzle ring B and is communicated with a turbine air inlet hole on the shell E, high-pressure driving gas enters the air inlet groove B02 from the turbine air inlet hole E02 on the shell E and drives the turbine to rotate after being accelerated by the gas nozzle B01. The turbine gas nozzle ring B is also provided with an exhaust hole B03 which communicates an exhaust groove A02 of the turbine with an exhaust channel on the housing E and exhausts the low-pressure gas of the turbine. Meanwhile, the size of a gap between the working surface of the gas thrust bearing C and the thrust surface A03 is controlled by adjusting the difference between the axial dimension of the turbine gas nozzle ring B and the axial dimension of the turbine.

As shown in fig. 4, two gas thrust bearings C are used, which belong to gas hydrostatic bearings, and are respectively installed on both sides of the turbine, and the side end surface of the turbine is used as a thrust surface a03 for controlling the axial movement of the rotor. The aerostatic bearing can provide sufficient thrust force in the full working rotating speed range, and meanwhile, the problem of abrasion of a direct contact type thrust bearing at high speed is avoided. The outer surface of the gas thrust bearing C is provided with an annular groove C01, and the thrust working surface is provided with an orifice C02 along the axial direction. The gas thrust bearing C is in interference fit with the shell E, and an annular groove C01 on the outer surface of the bearing C is matched with the shell E to form a gas flow equalizing groove and is communicated with a thrust bearing air inlet hole E03 on the shell E; high-pressure gas enters the annular groove C01 from a thrust bearing air inlet hole E03 on the shell E and flows through a thrust gap through a throttling hole C02 of the thrust bearing C to generate thrust.

As shown in fig. 5, the water-lubricated hybrid radial bearing D is a support member of the rotor a in which the turbine and the main shaft are integrated, and has two parts in total, an annular groove D01 is formed on the outer surface of the bearing, an orifice D02 is formed in the radial direction, and 4 cavities D03 are uniformly distributed in the circumferential direction on the inner surface of the bearing. Each cavity D03 is connected to the annular groove D01 through an orifice D02, the axial edge of the cavity D03 is rounded for ease of machining, and the orifice D02 is a simple thin-walled orifice. The water lubrication hybrid radial bearing D and the shell E are in interference fit, and an annular groove D01 on the outer surface of the bearing is matched with the shell E to form a water equalizing groove and is communicated with a hybrid bearing water inlet hole E01 on the shell E; the external system supplies water with certain pressure, enters the annular groove D01 from a dynamic and static pressure bearing water inlet hole E01 of the shell E, flows into the concave cavity D03 through the throttling hole D02, and then flows into a gap between the journal and the bearing to form a water lubricating liquid film to provide bearing force for the rotor.

As shown in fig. 6, the housing E is an integrated structure, and this design can improve the coaxiality of the two water-lubricated hybrid radial bearings D and make the structure more compact. When the bearing rotor system works, a turbine, two gas thrust bearings C and two water-lubricated dynamic and static pressure radial bearings D are arranged in a shell E, air supply or water supply and air exhaust and water drainage channels are needed, and therefore a dynamic and static pressure bearing water inlet hole E01, a turbine air inlet hole E02, a thrust bearing air inlet hole E03, an air exhaust hole E04 and a water exhaust hole E06 are formed in the wall surface of the shell E. For supplying water to the two water-lubricated hybrid bearings D at the same time, holes are axially punched on the wall surface of the shell E to communicate the annular grooves D01 of the two water-lubricated hybrid radial bearings D with the liquid inlet holes E01 of the hybrid bearings; in order to supply air to the two gas thrust bearings C simultaneously, the wall surface of the shell is also perforated along the axial direction, and a thrust bearing air inlet hole E03 is communicated with the annular grooves C01 of the two gas thrust bearings C. Sensor mounting holes E05 are also left on the housing E and on the sides thereof corresponding to the radial bearing end faces for mounting sensors for monitoring the vibration of the rotor at the two radial bearings.

As shown in fig. 7, which is a schematic view of end caps F, the two end caps are respectively installed at two ends of the housing and fixed by hexagon socket head cap bolts to limit axial movement of the water lubricated hybrid radial bearing D and the gas thrust bearing C in the housing E; the side surface of the end cover F is provided with a positioning hole F01, and a positioning pin can be arranged to prevent the water lubrication dynamic and static pressure radial bearing D from rotating; the matching part of the end cover F and the rotor adopts clearance sealing, and a plurality of clearance sealing grooves F02 are used for reducing the leakage of the lubricating medium water.

The invention provides a specific integral realization structure of a rotor system of a high-speed water lubrication hybrid bearing driven by a gas turbine, which has the advantages of compact structure, no pollution, high rotating speed and the like and can provide an ideal experimental research platform for the scientific research fields of rotor dynamics, liquid hybrid bearings, bearing rotor system dynamics and the like.

Claims

1. A gas turbine driven high speed water lubricated hybrid bearing rotor system, comprising: the device comprises a main shaft, a pneumatic turbine, a turbine gas nozzle ring, a gas thrust bearing, a water-lubricated dynamic and static pressure radial bearing, a shell and an end cover; during assembly, a turbine gas nozzle ring is installed in a shell, then an integrated rotor formed by the interference fit of a pneumatic turbine and a main shaft is installed, then a gas thrust bearing and a water lubrication dynamic and static pressure radial bearing are sequentially installed on two sides of the turbine respectively, and finally end covers are installed at two ends of the shell; the turbine gas nozzle ring, the gas thrust bearing and the water-lubricated dynamic and static pressure radial bearing are in interference fit with the shell;

the pneumatic turbine is an impulse turbine, the turbine and the main shaft are combined into an integrated rotor component in an interference fit mode, the outer end faces on two sides of the turbine are designed to be thrust faces of the gas thrust bearing, exhaust grooves are reserved on two axial sides of the turbine blade, and the exhaust grooves are exhaust channels of low-pressure gas of the turbine and also serve as one of the exhaust channels of the gas thrust bearing;

the turbine gas nozzle ring is provided with two rows of nozzles, each row of nozzles consists of a plurality of tangential gas nozzles which are uniformly distributed in the circumferential direction, the two rows of nozzles respectively correspond to two rows of turbine blades on the turbine, the outer circle surface of the nozzle ring is provided with an air inlet groove which is communicated with a turbine air inlet hole on the shell, high-pressure driving gas enters the air inlet groove from the turbine air inlet hole, and the high-pressure driving gas drives the turbine to rotate after being expanded and accelerated by the gas nozzles; the turbine gas nozzle ring is also provided with an exhaust hole which communicates an exhaust groove of the turbine with an exhaust channel on the shell; the size of a gap between a working surface and a thrust surface of the gas thrust bearing is controlled by adjusting the difference between the axial dimensions of the turbine gas nozzle ring and the turbine;

the gas thrust bearing is a gas hydrostatic bearing, an annular groove is formed in the outer circle surface of the gas thrust bearing, and the annular groove is matched with the shell to form a gas flow equalizing groove and is communicated with a thrust bearing air inlet hole in the shell to form an air supply channel of the gas thrust bearing; the two gas thrust bearings are respectively arranged on two sides of the turbine;

the water lubrication dynamic and static pressure radial bearing is characterized in that 4 concave cavities are uniformly distributed on the inner circular surface along the circumferential direction, and the edges of the 4 concave cavities along the axial direction are designed into arc-shaped transition; an annular groove is processed on the surface of the outer circle of the water lubrication dynamic and static pressure radial bearing, orifices are radially arranged, and each cavity is communicated with the annular groove through one orifice; the annular groove is matched with the shell to form a water equalizing groove and is communicated with a dynamic and static pressure bearing water inlet hole on the shell to form a water supply channel of the water lubrication dynamic and static pressure radial bearing;

the shell is of an integrated structure, a dynamic and static pressure bearing water inlet hole, a turbine air inlet hole and a thrust bearing air inlet hole which are arranged on the shell respectively form 3 independent water supply or air supply channels together with an annular groove of a water lubrication dynamic and static pressure radial bearing, an air inlet groove of a turbine air nozzle ring and an annular groove of an air thrust bearing, and the 3 channels are arranged on the shell and do not interfere with each other; the wall surface of the shell is axially perforated, a dynamic and static pressure bearing water inlet hole is communicated with the flow equalizing grooves of water of the two water lubrication dynamic and static pressure radial bearings, and a thrust bearing air inlet hole is communicated with the gas flow equalizing grooves of the two gas thrust bearings;

the end cover is fixed through the hexagon socket head cap screw, and the locating pin is installed to the end cover side to prevent the rotation of water lubrication hybrid radial bearing, and the end cover and the rotor matching part adopt clearance seal.

2. The air turbine driven high speed water lubricated hybrid bearing rotor system as claimed in claim 1, wherein said housing has sensor mounting holes on its upper and side surfaces near the end faces of the water lubricated hybrid radial bearings, and the sensors are mounted to measure the horizontal and vertical vibrations of the rotor at the two radial bearings.