CN220185419U - Centrifugal compressor and ammonia synthesis device - Google Patents

Abstract

The utility model provides a centrifugal compressor and an ammonia synthesis device, wherein the centrifugal compressor comprises a first sealing structure, a second sealing structure and a balance pipe, a balance cavity is formed between the first sealing structure and the second sealing structure, the balance cavity is communicated with the balance pipe, one end of the balance pipe, which is far away from the balance cavity, is used for being communicated with an inlet of the compressor, and a balance valve is arranged on the balance pipe and used for adjusting the pressure in the balance cavity. Through set up the balanced valve on the passageway balance pipe between compressor entry and balanced chamber to can realize the automatic balance of axial thrust through the valve of adjusting the balanced valve, when centrifugal compressor's actual operating condition and theoretical operating mode difference are great, can initiatively control centrifugal compressor's axial thrust to centrifugal compressor's main shaft, improved centrifugal compressor's the stability of the residual thrust that thrust axle bush bore when operating mode operation changes, greatly improved centrifugal compressor's security of operation.

Description

Centrifugal compressor and ammonia synthesis device

Technical Field

The utility model belongs to the technical field of centrifugal compressors, and particularly relates to a centrifugal compressor and an ammonia synthesis device.

Background

The centrifugal compressor is a machine for increasing the pressure of compressible fluid by mechanical energy, and can be divided into an axial-flow centrifugal compressor and a centrifugal compressor, wherein the centrifugal compressor is a vane rotary centrifugal compressor, namely a turbine centrifugal compressor, and when working medium passes through the centrifugal compressor, the working medium is driven by vanes rotating at high speed on an impeller, flows to the edge of the impeller under the action of centrifugal force, and the supercharging effect is realized through a diffuser.

During operation of the centrifugal compressor, the rotor generates axial thrust and is transferred to the thrust bearing via the thrust disc. If the axial thrust generated by the rotor is larger than the bearing value of the thrust bearing of the centrifugal compressor, the bearing temperature of the thrust bearing bush is too high, even the thrust bearing bush is burnt, or the axial movement of the rotor collides with the stator of the centrifugal compressor to cause the accident of the centrifugal compressor. In the prior art, a method for determining the residual axial external force of the centrifugal compressor by calculating the size of the balance disc in the design stage is generally adopted to avoid the problems, however, the load range of the centrifugal compressor applied to the fields of petrochemical industry, coal chemical industry and the like is larger, the running working conditions are more, and when the centrifugal compressor runs under different working conditions, the axial thrust difference of the centrifugal compressor is larger, so that the thrust tile temperature change is large. The prior art solution can only determine the axial thrust of the centrifugal compressor during the design phase of the centrifugal compressor, but cannot adjust the axial thrust during the operation phase of the centrifugal compressor, which cannot solve the above-mentioned problems.

Disclosure of Invention

The technical problem to be solved by the utility model is therefore to provide a centrifugal compressor and an ammonia synthesis device, wherein the centrifugal compressor can adjust the axial thrust in the operation phase so that the centrifugal compressor can stably operate under different working conditions.

In order to solve the above problems, according to one aspect of the present utility model, there is provided a centrifugal compressor including a first sealing structure, a second sealing structure, and a balance pipe, wherein a balance chamber is formed between the first sealing structure and the second sealing structure, the balance chamber is communicated with the balance pipe, one end of the balance pipe, which is far away from the balance chamber, is used for being communicated with an inlet of the compressor, and a balance valve is provided on the balance pipe, and is used for adjusting the pressure in the balance chamber.

Optionally, the first sealing structure includes stator end cover and stator axle head seal, stator axle head seal cover is established on the main shaft of centrifugal compressor, the stator end cover with stator axle head seal is connected, the balance through-hole has been seted up on the stator end cover, be formed with the medium flow passageway in the balance through-hole, the balance pipe passes through the balance through-hole with the balance chamber is linked together.

Optionally, the second seal structure includes stator baffle, stator balance plate seal and rotor balance plate, the stator baffle sets up the first direction side of stator end cover, the stator baffle with the stator end cover is connected, stator balance plate seal sets up the radial inboard of stator baffle, stator balance plate seal with the stator baffle is connected, the rotor balance plate sets up stator shaft end seal's first direction side, rotor balance plate cover is established on the main shaft, rotor balance plate with stator balance plate seal forms mechanical seal.

Optionally, a plurality of annular balancing grooves arranged along the axial direction of the rotor balancing disk are formed in the inner periphery of the stator balancing disk seal, and sealing elements are arranged in the balancing grooves.

Optionally, the brinell hardness of the stator balance disc seal is less than the brinell hardness of the rotor balance disc.

Optionally, the centrifugal compressor further comprises a thrust bearing and a thrust disc, the thrust bearing and the thrust disc are arranged on one side, far away from the first sealing structure, of the second sealing structure, the thrust bearing comprises a main thrust bearing bush and a secondary thrust bearing bush, the main thrust bearing bush and the secondary thrust bearing bush are arranged on a bearing bracket of the centrifugal compressor, the main thrust bearing bush is arranged on one side, far away from the second sealing structure, of the secondary thrust bearing bush, and the thrust disc is arranged between the main thrust bearing bush and the secondary thrust bearing bush and sleeved on a main shaft of the centrifugal compressor.

In another aspect of the present utility model, there is provided an ammonia plant comprising a centrifugal compressor as described above.

Optionally, the ammonia synthesis device comprises an induction part, the induction part comprises a first induction unit and a second induction unit, the first induction unit is arranged on the main thrust bearing bush, the first induction unit is used for detecting the temperature of the main thrust bearing bush, the second induction unit is arranged on the auxiliary thrust bearing bush, and the second induction unit is used for detecting the temperature of the auxiliary thrust bearing bush.

Optionally, the ammonia synthesis device further comprises an upper computer, wherein the upper computer is respectively and electrically connected with the first induction unit and the second induction unit, and the upper computer is used for obtaining the temperature values of the main thrust bearing bush and the auxiliary thrust bearing bush.

Optionally, the balance valve is an electromagnetic valve.

Advantageous effects

According to the centrifugal compressor and the ammonia synthesis device provided by the embodiment of the utility model, the balance pipe is arranged to enable the balance cavity to be communicated with the inlet of the compressor, and the balance valve is arranged on the balance pipe to adjust the pressure in the balance cavity, so that the axial thrust borne by the main shaft can be adjusted. In the prior art, the residual axial external force of the centrifugal compressor is usually determined by calculating the size of the balance disc in the design stage, but the load range is larger in the working process of the centrifugal compressor, the running working conditions are more, and the axial thrust difference of the centrifugal compressor is larger when the centrifugal compressor runs under different working conditions, so that the centrifugal compressor cannot be matched with the set parameters. Compared with the prior art, in the utility model, the balance valve is arranged on the channel balance pipe between the inlet of the compressor and the balance cavity, and the automatic balance of the axial thrust is realized by adjusting the valve of the balance valve, so that when the actual running working condition of the centrifugal compressor is greatly different from the theoretical working condition, the axial thrust of the main shaft of the centrifugal compressor can be actively controlled on the basis of not affecting other functions of the centrifugal compressor, the stability of the residual thrust born by the thrust bearing bush of the centrifugal compressor during the working condition running conversion is improved, thereby avoiding the safety accident caused by the overhigh temperature damage of the thrust bearing bush, and greatly improving the running safety of the centrifugal compressor.

Drawings

Fig. 1 is a sectional view of a centrifugal compressor according to an embodiment of the present utility model.

The reference numerals are expressed as:

1. a first sealing structure; 11. a stator end cap; 12. sealing the end of the stator shaft; 2. a second sealing structure; 21. a stator separator; 22. sealing the stator balance disc; 23. a rotor balance disc; 3. a balance tube; 4. a balancing cavity; 5. a balancing valve; 6. balance through holes; 7. a thrust bearing; 71. a main thrust bearing bush; 72. a secondary thrust bearing bush; 8. a thrust plate; 9. a compressor inlet; 10. a main shaft.

Detailed Description

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present utility model, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

The preferred embodiments of the present utility model will be described below with reference to the accompanying drawings, it being understood that the preferred embodiments described herein are for illustration and explanation of the present utility model only, and are not intended to limit the present utility model.

Referring to fig. 1 in combination, according to an aspect of the embodiment of the present utility model, there is provided a centrifugal compressor including a first sealing structure 1, a second sealing structure 2, and a balance pipe 3, wherein a balance chamber 4 is formed between the first sealing structure 1 and the second sealing structure 2, the balance chamber 4 is communicated with the balance pipe 3, one end of the balance pipe 3 away from the balance chamber 4 is used for being communicated with a compressor inlet 9, a balance valve 5 is provided on the balance pipe 3, and the balance valve 5 is used for adjusting the pressure in the balance chamber 4.

According to the centrifugal compressor provided by the embodiment of the utility model, the balance pipe 3 is arranged so that the balance cavity 4 can be communicated with the compressor inlet 9, and the balance valve 5 is arranged on the balance pipe 3 to adjust the pressure in the balance cavity 4, so that the axial thrust borne by the main shaft 10 can be adjusted. In the prior art, the residual axial external force of the centrifugal compressor is usually determined by calculating the size of the balance disc in the design stage, but the load range is larger in the working process of the centrifugal compressor, the running working conditions are more, and the axial thrust difference of the centrifugal compressor is larger when the centrifugal compressor runs under different working conditions, so that the centrifugal compressor cannot be matched with the set parameters. Compared with the prior art, in the utility model, the balance valve 5 is arranged on the channel balance pipe 3 between the compressor inlet 9 and the balance cavity 4, and the automatic balance of the axial thrust is realized by adjusting the valve of the balance valve 5, so that when the actual operation working condition of the centrifugal compressor is greatly different from the theoretical working condition, the axial thrust of the main shaft 10 of the centrifugal compressor can be actively controlled on the basis of not influencing other functions of the centrifugal compressor, the stability of the residual thrust born by the thrust bearing bush of the centrifugal compressor during the operation conversion of the working condition is improved, thereby avoiding the safety accident caused by the over-high temperature damage of the thrust bearing bush, and greatly improving the operation safety of the centrifugal compressor.

The centrifugal compressor may be a single-stage centrifugal compressor or a multistage centrifugal compressor, which is not limited in the present utility model.

The centrifugal compressor comprises a first sealing structure 1, wherein the first sealing structure 1 is arranged at the outlet of the compressor, and the first sealing structure 1 is used for sealing gas passing through the multistage impeller centrifugal compressor so that the compressed gas can be discharged from the outlet of the compressor.

The centrifugal compressor further comprises a second sealing structure 2, the second sealing structure 2 is arranged on one side, far away from the compressor inlet 9, of the first sealing structure 1, and the second sealing structure 2 is used for sealing gas leaked from the first sealing structure 1, so that the working stability of the centrifugal compressor is improved.

Specifically, a gap is formed between the first sealing structure 1 and the second sealing structure 2 to form a balance cavity 4, the balance cavity 4 is a high pressure side of the centrifugal compressor, and compressed high pressure gas leaked through the first sealing structure 1 enters the balance cavity 4. The compressor inlet 9 is an uncompressed gas, i.e. the compressor inlet 9 is on the low pressure side.

The centrifugal compressor further comprises a balance pipe 3, one end of the balance pipe 3 is communicated with the balance cavity 4, and the other end of the balance pipe is communicated with the compressor inlet 9, so that gas at a high pressure side can enter the compressor inlet 9 through the balance pipe 3, and the pressure difference at two axial sides of the main shaft 10 is balanced, and the generation of axial thrust is avoided.

Specifically, the balance valve 5 is disposed on the balance pipe 3, and the balance valve 5 may be a ball valve, a stop valve, or an electromagnetic valve, which is not limited in the present utility model. The pressure in the balance cavity 4 can be regulated by arranging the balance valve 5 until the pressure difference between the compressor inlet 9 and the balance cavity 4 disappears, the axial thrust of the centrifugal compressor is balanced, and at the moment, the temperature of the thrust bearing bush is restored to a set value, so that the safety accident caused by the over-high temperature damage of the thrust bearing bush can be avoided, and the running stability and safety of the centrifugal compressor are greatly improved.

The first sealing structure 1 comprises a stator end cover 11 and a stator shaft end seal 12, the stator shaft end seal 12 is sleeved on a main shaft 10 of the centrifugal compressor, the stator end cover 11 is connected with the stator shaft end seal 12, a balance through hole 6 is formed in the stator end cover 11, a medium flow channel is formed in the balance through hole 6, and the balance pipe 3 is communicated with the balance cavity 4 through the balance through hole 6.

The high-pressure gas in the balance cavity 4 can be discharged through the balance through hole 6, so that the pressure of the balance cavity 4 is equal to that of the inlet 9 of the compressor, axial thrust balance of the centrifugal compressor can be realized, safety accidents caused by overhigh temperature damage of a thrust bearing bush can be avoided, and the running stability and safety of the centrifugal compressor are greatly improved.

The first sealing structure 1 includes a stator end cover 11, the stator end cover 11 may be a cover plate at an end of a centrifugal compressor housing, the stator end cover 11 is connected with the centrifugal compressor housing, and a connection manner of the stator end cover 11 may be bolting or welding, etc., which is not limited in the present utility model.

Wherein the stator end cap 11 is substantially annular.

The first sealing structure 1 further includes a stator shaft end seal 12, the stator shaft end seal 12 is disposed on a radial inner wall of the stator end cover 11, the stator shaft end seal 12 is connected with the stator end cover 11, and a connection manner of the stator shaft end seal 12 may be bolt connection or welding, etc., which is not limited in the present utility model.

Specifically, the stator shaft end seal 12 is sleeved on the main shaft 10 of the centrifugal compressor.

The main shaft 10 of the centrifugal compressor is a rotor component of the centrifugal compressor, and the stator end cover 11 and the stator shaft end seal 12 are stator components of the centrifugal compressor.

Wherein, the stator end cover 11 is provided with a balance hole, and the balance hole penetrates through the stator end cover 11 to form a medium flow channel.

Specifically, a high-pressure gas flow channel is formed in the balance hole, high-pressure gas in the balance cavity 4 enters the balance pipe 3 through the balance hole and then enters the compressor inlet 9 through the balance valve 5, so that the pressure in the balance cavity 4 is reduced until the pressure of the balance cavity 4 is the same as that of the compressor inlet 9, and the axial thrust of the centrifugal compressor disappears.

The second sealing structure 2 comprises a stator partition plate 21, a stator balance disc seal 22 and a rotor balance disc 23, wherein the stator partition plate 21 is arranged on the first direction side of the stator end cover 11, the stator partition plate 21 is connected with the stator end cover 11, the stator balance disc seal 22 is arranged on the radial inner side of the stator partition plate 21, the stator balance disc seal 22 is connected with the stator partition plate 21, the rotor balance disc 23 is arranged on the first direction side of the stator shaft end seal 12, the rotor balance disc 23 is sleeved on the main shaft 10, and the rotor balance disc 23 and the stator balance disc seal 22 form mechanical seal.

Through setting up the balance disc and making the balance disc set up on main shaft 10 available balance disc both sides gaseous pressure differential come balanced a part centrifugal compressor axial thrust, remaining axial thrust is born by thrust disc 8, can reduce the axial force that thrust disc 8 received through setting up the balance disc promptly, and then can avoid the too high damage of thrust axle bush temperature to cause the incident, greatly improved centrifugal compressor operation's stability and security.

The second sealing structure 2 includes a stator separator 21, where the stator separator 21 is disposed at a first direction side of the stator end cover 11, and the stator separator 21 is connected to the stator end cover 11, and a connection manner of the stator separator 21 may be bolting or welding, etc., which is not limited in the present utility model.

Wherein the first direction may be the direction of the compressor outlet towards the compressor inlet 9.

The second sealing structure 2 further includes a stator balance disc seal 22 and a rotor balance disc 23, the rotor balance disc 23 is sleeved on the main shaft 10 of the centrifugal compressor, the stator balance disc is disposed on the radial inner side of the stator partition 21, and the stator balance disc is connected with the stator partition 21 in a bolt connection manner, etc., which is not limited in the utility model.

Specifically, stator balance disc seal 22 is laminated mutually with rotor balance disc 23 to form mechanical seal, can avoid the high-pressure gas that compresses through multistage impeller to reveal, can balance a part centrifugal compressor axial thrust simultaneously, thereby reduce the axial force that thrust bearing bush received, reduced thrust bearing bush temperature, improved centrifugal compressor operation's stability and security.

The stator balance disc seal 22 has a plurality of annular balance grooves arranged in the axial direction of the rotor balance disc 23 on the inner periphery thereof, and a seal member is provided in the balance groove.

By arranging a plurality of annular balancing grooves which are arranged along the axial direction of the rotor balancing disk 23 on the inner periphery of the stator balancing disk seal 22 and arranging sealing elements in the balancing grooves, the sealing effect of the first sealing structure 1 is improved, so that the total amount of high-pressure gas entering the balancing cavity 4 is reduced, the internal pressure of the balancing cavity 4 is reduced, the axial thrust of the centrifugal compressor is reduced, and the stability and the safety of the operation of the centrifugal compressor are improved.

Wherein, the balancing groove is set up on the inner peripheral wall of stator balance disc seal 22, and the balancing groove can set up a plurality of, and a plurality of balancing grooves are arranged along the axial direction array of stator balance disc seal 22.

Specifically, in the embodiment of the present utility model, the balance groove is annular.

The balance groove is internally provided with a sealing element, the sealing element can be an O-shaped sealing ring and the like, and the sealing effect can be improved.

The brinell hardness of the stator balance disc seal 22 is less than the brinell hardness of the rotor balance disc 23.

The Brinell hardness of the stator balance disc seal 22 is smaller than the Brinell hardness of the rotor balance disc 23, so that the rotor balance disc 23 can be protected from abrasion in the running process of the centrifugal compressor, the service life of the rotor balance disc 23 is prolonged, and the sealing effect of the second sealing structure 2 is improved.

The centrifugal compressor further comprises a thrust bearing 7 and a thrust disc 8, wherein the thrust bearing 7 and the thrust disc 8 are arranged on one side, far away from the first sealing structure 1, of the second sealing structure 2, the thrust bearing 7 comprises a main thrust bearing bush 71 and a secondary thrust bearing bush 72, the main thrust bearing bush 71 and the secondary thrust bearing bush 72 are arranged on a bearing bracket of the centrifugal compressor, the main thrust bearing bush 71 is arranged on one side, far away from the second sealing structure 2, of the secondary thrust bearing bush 72, and the thrust disc 8 is arranged between the main thrust bearing bush 71 and the secondary thrust bearing bush 72 and is sleeved on a main shaft 10 of the centrifugal compressor.

The thrust bearing 7 and the thrust disc 8 are arranged to bear the axial thrust borne by the main shaft 10 in the running process of the centrifugal compressor, so that the axial relative position of the main shaft 10 of the centrifugal compressor and the centrifugal compressor shell is unchanged, the accident of the centrifugal compressor caused by the axial movement of the rotor of the centrifugal compressor and the collision of the stator of the centrifugal compressor is avoided, and the working safety is improved.

Wherein the thrust disc 8 is arranged at a first directional side of the centrifugal compressor wheel, i.e. the thrust disc 8 is arranged at a side of the wheel remote from the first sealing structure 1.

Specifically, the thrust disc 8 is sleeved on the main shaft 10 of the centrifugal compressor, and the thrust disc 8 is fixedly connected with the main shaft 10 of the centrifugal compressor, so that axial movement of the main shaft 10 can be realized, and the thrust disc 8 can be driven to move axially.

The thrust bearing 7 is connected with the shell of the centrifugal compressor, the centrifugal compressor further comprises a bearing bracket, the thrust bearing 7 is arranged on the bearing bracket, and the thrust bearing 7 is connected with the shell of the centrifugal compressor through the bearing bracket, so that the axial direction position of the thrust bearing 7 is kept unchanged in the running process of the centrifugal compressor.

Specifically, the thrust bearing 7 includes a main thrust bearing bush 71 and a sub thrust bearing bush 72, the main thrust bearing bush 71 is disposed at a first direction side of the thrust disc 8, and the main thrust bearing bush 71 is used for limiting the thrust disc 8 in the first direction, that is, limiting the main shaft 10 of the centrifugal compressor in the first direction; the secondary thrust bearing bush 72 is disposed on the opposite side of the first direction of the thrust disc 8, and the secondary thrust bearing bush 72 is configured to limit the thrust disc 8 in the opposite direction of the first direction, i.e., limit the centrifugal compressor main shaft 10 in the opposite direction of the first direction. It will be appreciated that by providing the thrust bearing 7, the thrust disc 8 can be restrained in the axial direction of the centrifugal compressor, and further axial movement of the centrifugal compressor main shaft 10 can be avoided.

Working principle:

in the utility model, before the centrifugal compressor is started, the balance valve 5 is in a normally open state. In the operation process, when the temperature of the auxiliary thrust bearing bush 72 is higher than that of the main thrust bearing bush 71, gradually closing the balance valve 5, if the temperature of the auxiliary thrust bearing bush 72 is higher than that of the main thrust bearing bush 71, continuing to close the balance valve 5; when the temperature of the auxiliary thrust bearing bush 72 is lower than that of the main thrust bearing bush 71, the balance valve 5 is gradually opened, so that the temperature of the main thrust bearing bush 71 is reduced, and if the effect is not obvious, the balance valve 5 is continuously fully opened. After the axial thrust of the centrifugal compressor is adjustable through the arrangement of the balance valve 5, the problem that the thrust bearing bush is high due to deviation between the axial thrust and the design parameters in actual operation of the unit site is solved, the problem that the load adjustment range of the device is large, the axial thrust of the centrifugal compressor is changed greatly and the operation of the device is limited is solved. The fixed value is realized to the stepless regulation value, and the load limit of the centrifugal compressor is thoroughly solved.

In another aspect of the embodiments of the present utility model, there is provided an ammonia plant comprising the centrifugal compressor described above.

The ammonia synthesis device comprises an induction part, the induction part comprises a first induction unit and a second induction unit, the first induction unit is arranged on the main thrust bearing bush 71 and used for detecting the temperature of the main thrust bearing bush 71, the second induction unit is arranged on the auxiliary thrust bearing bush 72 and used for detecting the temperature of the auxiliary thrust bearing bush 72.

The temperature of the main thrust bearing bush 71 and the temperature of the auxiliary thrust bearing bush 72 can be detected through the arrangement of the sensing part, so that a worker can compare the temperatures of the main thrust bearing bush 71 and the auxiliary thrust bearing bush 72 to control the opening degree of the regulating valve, and compared with the traditional method that the worker senses the temperature by touching the thrust bearing 7 by hands, the safety of work is improved through the arrangement of the sensing part, meanwhile, the detection precision is higher, and the control precision of the balance valve 5 is improved.

The first sensing unit and the second sensing unit may be other temperature detecting elements such as a temperature sensor, and the utility model is not limited thereto.

Specifically, in the embodiment of the present utility model, the first sensing unit and the second sensing unit are temperature sensors, and the model is PT1000. The first sensing unit is arranged on the main thrust bearing bush 71 and is used for detecting the temperature of the main thrust bearing bush 71; the second sensing unit is provided on the sub thrust bearing bush 72, and the second sensing unit is used for detecting the temperature of the sub thrust bearing bush 72.

The ammonia synthesis device further comprises an upper computer, wherein the upper computer is respectively and electrically connected with the first sensing unit and the second sensing unit, and the upper computer is used for acquiring temperature values of the main thrust bearing bush 71 and the auxiliary thrust bearing bush 72.

By arranging the upper computer to automatically acquire the temperature values of the main thrust bearing bush 71 detected by the first sensing unit and the auxiliary thrust bearing bush 72 detected by the second sensing unit, the automation degree of the device is improved.

The upper computer can be a computer, a singlechip or a PLC system and the like, and can collect and process data, and the utility model is not limited further.

Specifically, the upper computer is electrically connected with the first sensing unit and the second sensing unit respectively.

The balancing valve 5 is a solenoid valve.

The balance valve 5 is arranged to be an electromagnetic valve, and the electromagnetic valve is electrically connected with the upper computer, so that the upper computer can automatically adjust the opening of the electromagnetic valve according to the obtained temperature values of the main thrust bearing bush 71 and the auxiliary thrust bearing bush 72, the pressure of the balance cavity 4 is equal to the pressure of the compressor inlet 9, and the automation degree of the device is improved.

The centrifugal compressor and the ammonia synthesis device provided by the embodiment of the utility model mainly have the advantages that the balance pipe 3 is arranged to enable the balance cavity 4 to be communicated with the inlet 9 of the compressor, and the balance valve 5 is arranged on the balance pipe 3 to adjust the pressure in the balance cavity 4, so that the axial thrust borne by the main shaft 10 can be adjusted. In the prior art, the residual axial external force of the centrifugal compressor is usually determined by calculating the size of the balance disc in the design stage, but the load range is larger in the working process of the centrifugal compressor, the running working conditions are more, and the axial thrust difference of the centrifugal compressor is larger when the centrifugal compressor runs under different working conditions, so that the centrifugal compressor cannot be matched with the set parameters. Compared with the prior art, in the utility model, the balance valve 5 is arranged on the channel balance pipe 3 between the compressor inlet 9 and the balance cavity 4, and the automatic balance of the axial thrust is realized by adjusting the valve of the balance valve 5, so that when the actual operation working condition of the centrifugal compressor is greatly different from the theoretical working condition, the axial thrust of the main shaft 10 of the centrifugal compressor can be actively controlled on the basis of not influencing other functions of the centrifugal compressor, the stability of the residual thrust born by the thrust bearing bush of the centrifugal compressor during the operation conversion of the working condition is improved, thereby avoiding the safety accident caused by the over-high temperature damage of the thrust bearing bush, and greatly improving the operation safety of the centrifugal compressor.

It will be readily appreciated by those skilled in the art that the above advantageous ways can be freely combined and superimposed without conflict.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the utility model. The foregoing is merely a preferred embodiment of the present utility model, and it should be noted that it will be apparent to those skilled in the art that modifications and variations can be made without departing from the technical principles of the present utility model, and these modifications and variations should also be regarded as the scope of the utility model.

Claims (10)

1. The utility model provides a centrifugal compressor, its characterized in that includes first seal structure (1), second seal structure (2) and balance pipe (3), first seal structure (1) with form balance chamber (4) between second seal structure (2), balance chamber (4) with balance pipe (3) are linked together, balance pipe (3) keep away from one end of balance chamber (4) is used for being linked together with compressor entry (9), be provided with balance valve (5) on balance pipe (3), balance valve (5) are used for adjusting pressure in balance chamber (4).

2. Centrifugal compressor according to claim 1, wherein the first sealing structure (1) comprises a stator end cover (11) and a stator shaft end seal (12), the stator shaft end seal (12) is sleeved on a main shaft (10) of the centrifugal compressor, the stator end cover (11) is connected with the stator shaft end seal (12), a balancing through hole (6) is formed in the stator end cover (11), a medium flow channel is formed in the balancing through hole (6), and the balancing pipe (3) is communicated with the balancing cavity (4) through the balancing through hole (6).

3. Centrifugal compressor according to claim 2, wherein the second sealing structure (2) comprises a stator diaphragm (21), a stator balance disc seal (22) and a rotor balance disc (23), wherein the stator diaphragm (21) is arranged on a first direction side of the stator end cover (11), the stator diaphragm (21) is connected with the stator end cover (11), the stator balance disc seal (22) is arranged on a radial inner side of the stator diaphragm (21), the stator balance disc seal (22) is connected with the stator diaphragm (21), the rotor balance disc (23) is arranged on the first direction side of the stator shaft end seal (12), the rotor balance disc (23) is sleeved on the main shaft (10), and the rotor balance disc (23) forms a mechanical seal with the stator balance disc seal (22).

4. A centrifugal compressor according to claim 3, wherein the stator balance disc seal (22) is provided on its inner periphery with a number of annular balance grooves arranged in the axial direction of the rotor balance disc (23), in which balance grooves seals are provided.

5. Centrifugal compressor according to claim 4, wherein the brinell hardness of the stator balance disc seal (22) is smaller than the brinell hardness of the rotor balance disc (23).

6. Centrifugal compressor according to claim 1, further comprising a thrust bearing (7) and a thrust disc (8), the thrust bearing (7) and the thrust disc (8) being arranged on a side of the second sealing structure (2) remote from the first sealing structure (1), the thrust bearing (7) comprising a main thrust bearing bush (71) and a secondary thrust bearing bush (72), the main thrust bearing bush (71) and the secondary thrust bearing bush (72) being arranged on a bearing carrier of the centrifugal compressor, the main thrust bearing bush (71) being arranged on a side of the secondary thrust bearing bush (72) remote from the second sealing structure (2), the thrust disc (8) being arranged between the main thrust bearing bush (71) and the secondary thrust bearing bush (72) and being sleeved on a main shaft (10) of the centrifugal compressor.

7. An ammonia plant comprising a centrifugal compressor according to any one of claims 1 to 6.

8. The ammonia synthesis device according to claim 7, comprising a sensing section comprising a first sensing unit arranged on the primary thrust bearing (71) and a secondary thrust bearing (72) when the centrifugal compressor comprises the primary thrust bearing (71) and the secondary thrust bearing (72), the first sensing unit being arranged to detect the temperature of the primary thrust bearing (71) and the second sensing unit being arranged on the secondary thrust bearing (72) and the second sensing unit being arranged to detect the temperature of the secondary thrust bearing (72).

9. The ammonia synthesis device according to claim 8, further comprising an upper computer electrically connected to the first and second sensing units, respectively, the upper computer being configured to obtain temperature values of the primary thrust bearing (71) and the secondary thrust bearing (72).

10. The ammonia synthesis device according to claim 9, wherein the balancing valve (5) is a solenoid valve.