Sufficient cooling system of gas compressor

Abstract

The invention relates to the technical field of gas compressors, in particular to a sufficient cooling system of a gas compressor. An interstage cooling pipe is arranged in the interstage connecting pipe, the interstage cooling pipe is connected with an interstage cooling system, the interstage cooling system comprises a condenser connected with a second-stage air outlet of the second-stage compression pump head through a pipeline, and the other branch of a liquid outlet of the condenser is connected with an inlet of the interstage cooling pipe through a second expansion valve; the inner surface of the shell is provided with a steel sheet groove along the circumference, the inner surface of the steel sheet groove is provided with continuously arranged gas guide grooves, the shell is provided with a cooling gas inlet corresponding to the front end position of the gas guide grooves, and the other shell of the stator is provided with a cooling gas outlet; a boss is arranged on the side wall of the side, close to the motor cavity, of the bearing seat, and a plurality of heat dissipation channels enabling an inner hole of the bearing seat to be communicated with the motor cavity are formed in the boss along the circumference. The rotating speed can be increased, the air displacement is increased, the refrigerating efficiency is improved, heat is prevented from being accumulated in the motor cavity, and the radial air bearing and the motor are protected.

Description

Technical field:

[0001] The present invention relates to the technical field of gas compressors, and in particular to a sufficient cooling system for a gas compressor. Background technology:

[0002] At present, in two-stage high-speed centrifugal air compressors, the motor drives two-stage compression chambers at the same time to pressurize the air. The two-stage compression chambers are connected by a connecting pipe. The gas discharged from the first-stage compression chamber enters the second-stage compression chamber through the connecting pipe for re-pressurization to form high-pressure gas. This compressor is often used in air-conditioning systems. In actual use, it still has the following disadvantages:

[0003] First, there are requirements for the outlet temperature of the compressor in the air conditioning system. Under the premise of ensuring the outlet volume, the secondary outlet temperature is generally required to be about 10°C higher than the room temperature. The compressor speed is positively correlated with the outlet temperature. If you want a high speed, a large outlet volume, and a low outlet temperature, you need a low intake temperature. The intake temperature involves the intake temperature of the primary compression chamber on the one hand, and the intake temperature of the secondary compression chamber on the other hand. At present, it is difficult to control the intake temperature of the secondary compression chamber, which leads to a decrease in speed, a decrease in exhaust volume, and a decrease in refrigeration efficiency.

[0004] Second, the cooling of the motor is currently mainly done by a water cooling system. A water cooling channel is set in the motor housing, and cooling water flows through the water cooling channel. The cooling water takes away heat through heat exchange with the stator and the housing. This cooling method using a water cooling system can only quickly cool the part of the stator close to the housing, and then slowly cool it from the outside to the inside by heat conduction. The cooling effect is poor, and the heat inside the stator cannot be quickly discharged, resulting in heat accumulation inside the stator, which is prone to over-temperature shutdown of the motor, affecting the life of the motor;

[0005] Third, the cooling effect of radial air bearings is currently poor, and they mainly rely on the gap between the bearing and the inner hole of the bearing seat for natural ventilation and heat dissipation. The bearings have a short life and are easily damaged, and cannot meet the long-term working environment of high-speed centrifugal air compressors.

[0006] In summary, the above-mentioned problems of two-stage gas compressors during use have become technical problems that need to be solved urgently in the industry. Summary of the invention:

[0007] In order to make up for the deficiencies of the prior art, the present invention provides a sufficient cooling system for a gas compressor, which solves the problem that the intake temperature of the secondary compression chamber is difficult to control, resulting in reduced speed, reduced exhaust volume, and reduced refrigeration efficiency; solves the problem that the previous motor uses a water cooling system with poor cooling effect and cannot quickly export the heat inside the stator; and solves the problem that the previous radial air bearing has poor cooling effect, short life, and easy damage.

[0008] The technical solution adopted by the present invention to solve the above technical problems is:

[0009] A sufficient cooling system for a gas compressor includes a motor, the end of the motor is connected to a primary compression pump head and a secondary compression pump head, the primary air outlet of the primary compression pump head and the secondary air inlet of the secondary compression pump head are connected through an interstage connecting pipe, the motor includes a housing, a stator and a main shaft are arranged in the housing, both ends of the main shaft are supported by a bearing seat, and a radial air bearing is arranged between the bearing seat and the main shaft.

[0010] An interstage cooling pipe is arranged in the interstage connecting pipe, and the interstage cooling pipe is connected to the interstage cooling system, and the interstage cooling system includes a condenser connected to the secondary air outlet of the secondary compression pump head through a pipeline, a branch of the liquid outlet of the condenser is connected to the inlet of the evaporator through a first expansion valve, the air outlet of the evaporator is connected to the primary air inlet of the primary compression pump head through a pipeline, another branch of the liquid outlet of the condenser is connected to the inlet of the interstage cooling pipe through a second expansion valve, and the air outlet of the interstage cooling pipe is connected to the primary air inlet of the primary compression pump head through a pipeline;

[0011] The inner surface of the shell is provided with steel sheet grooves along the circumference, and the steel sheet grooves are used to install and fix the steel sheets of the stator. The steel sheets are installed in a sealed manner in the steel sheet grooves. The inner surface of the steel sheet grooves is provided with continuously arranged air guide grooves, and the head and tail of the air guide grooves are spaced apart. A cooling gas inlet is provided at the front end position of the shell corresponding to the air guide groove, and an exhaust groove for discharging the gas to one side of the stator is provided at the tail end position of the air guide groove on the inner surface of the shell. A cooling gas outlet is provided on the other shell of the stator, and the cooling gas inlet and the cooling gas outlet are respectively connected to the interstage connecting pipe through pipelines;

[0012] A boss is provided on the side wall of the bearing seat close to the motor cavity, and a plurality of heat dissipation channels are provided along the circumference of the boss to connect the inner hole of the bearing seat with the motor cavity. The cooling gas in the motor cavity enters the inner hole of the bearing seat through the heat dissipation channel to cool the radial air bearing.

[0013] The condenser is used to cool the high-temperature gas discharged from the secondary gas outlet and convert the gas into liquid.

[0014] The first expansion valve and the second expansion valve are used to atomize the liquid discharged from the condenser.

[0015] The evaporator is used to gasify the mist discharged from the first expansion valve and cool the surrounding air to blow out cold wind.

[0016] The interstage cooling pipe performs heat exchange in the interstage connecting pipe, and the mist discharged from the second expansion valve in the interstage cooling pipe is gasified, and the surrounding air is cooled to cool the gas in the interstage connecting pipe.

[0017] The interstage cooling pipe is arranged inside the interstage connecting pipe in a zigzag shape, a coil shape or a labyrinth shape.

[0018] The steel sheet and the edge of the steel sheet groove are sealed by sealant.

[0019] The shape of the air guide grooves includes a continuously arranged S-shape, a W-shape or a spiral shape.

[0020] The present invention adopts the above scheme and has the following advantages:

[0021] By providing an interstage cooling pipe in the interstage connecting pipe, the liquid discharged from the condenser is atomized by the second expansion valve, and then enters the interstage cooling pipe to exchange heat with the gas in the interstage connecting pipe. On the one hand, the mist discharged from the second expansion valve is gasified and then passed into the first-stage air inlet of the two-stage gas compressor. On the other hand, the surrounding air is cooled to cool the gas in the interstage connecting pipe, thereby reducing the temperature of the gas entering the second-stage air inlet, which can ultimately increase the rotation speed, increase the exhaust volume, and improve the refrigeration efficiency.

[0022] By providing a continuously arranged air guide groove in the steel sheet groove on the inner surface of the shell, an exhaust groove for discharging the gas to one side of the stator is provided at the tail end position of the inner surface of the shell corresponding to the air guide groove, and a cooling gas outlet is provided on the other shell of the stator, and the cooling gas in the interstage connecting pipe can enter the air guide groove through the pipeline through the cooling gas inlet to directly cool the steel sheet of the stator, and then the cooling gas in the air guide groove is discharged to the motor cavity on one side of the stator through the exhaust groove, which can cool the stator winding package on this side, and then discharged to the motor cavity on the other side of the stator through the gap between the stator and the main shaft, cooling the stator winding package on the other side, and finally discharged to the interstage connecting pipe through the cooling gas outlet. The present invention replaces the previous water cooling form with air cooling, which can not only directly cool the steel sheet and the winding packages on both sides of the stator, with good cooling effect, but also can carry and discharge the heat inside the motor cavity in time, avoiding the accumulation of heat in the motor cavity, protecting the motor, and extending the service life of the motor.

[0023] A boss is provided on the side wall of the bearing seat close to the motor cavity, and a plurality of heat dissipation channels are provided along the circumference of the boss to connect the inner hole of the bearing seat with the motor cavity. The cooling gas in the motor cavity can also enter the inner hole of the bearing seat through the heat dissipation channel to cool the radial air bearing. The cooling effect is good, the heat dissipation is fast, the failure rate is low, and the service life of the radial air bearing is extended. Description of the drawings:

[0024] Figure 1 It is a cross-sectional structural schematic diagram of the present invention.

[0025] Figure 2 It is a schematic diagram of the principle of the interstage cooling system of the present invention.

[0026] Figure 3 It is a schematic diagram of the three-dimensional structure of the motor housing of the present invention.

[0027] Figure 4 It is a schematic cross-sectional structural diagram of the motor housing of the present invention.

[0028] Figure 5 It is a schematic diagram of the three-dimensional structure of the bearing seat of the present invention.

[0029] Figure 6 It is a schematic cross-sectional structure diagram of the position of the boss of the bearing seat of the present invention.

[0030] In the figure, 1. motor, 2. first-stage compression pump head, 3. second-stage compression pump head, 4. first-stage air inlet, 5. first-stage air outlet, 6. second-stage air inlet, 7. second-stage air outlet, 8. shell, 9. stator, 10. main shaft, 11. bearing seat, 12. radial air bearing, 13. interstage connecting pipe, 14. interstage cooling pipe, 15. condenser, 16. first expansion valve, 17. evaporator, 18. second expansion valve, 19. steel sheet groove, 20. air guide groove, 21. cooling gas inlet, 22. exhaust groove, 23. cooling gas outlet, 24. boss, 25. heat dissipation channel. Specific implementation method:

[0031] In order to clearly illustrate the technical features of the present solution, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0032] like Figure 1-6 As shown, a sufficient cooling system for a gas compressor includes a motor 1, the end of the motor 1 is connected to a primary compression pump head 2 and a secondary compression pump head 3, the primary air outlet 5 of the primary compression pump head 2 and the secondary air inlet 6 of the secondary compression pump head 3 are connected through an interstage connecting pipe 13, the motor 1 includes a housing 8, a stator 9 and a main shaft 10 are arranged in the housing 8, both ends of the main shaft 10 are supported by a bearing seat 11, and a radial air bearing 12 is arranged between the bearing seat 11 and the main shaft 10,

[0033] An interstage cooling pipe 14 is provided in the interstage connecting pipe 13, and the interstage cooling pipe 14 is connected to the interstage cooling system, and the interstage cooling system includes a condenser 15 connected to the secondary air outlet 7 of the secondary compression pump head 3 through a pipeline, a branch of the liquid outlet of the condenser 15 is connected to the inlet of the evaporator 17 through a first expansion valve 16, and the air outlet of the evaporator 17 is connected to the primary air inlet 4 of the primary compression pump head 2 through a pipeline, and another branch of the liquid outlet of the condenser 15 is connected to the inlet of the interstage cooling pipe 14 through a second expansion valve 18, and the air outlet of the interstage cooling pipe 14 is connected to the primary air inlet 4 of the primary compression pump head 2 through a pipeline;

[0034] The inner surface of the shell 8 is provided with a steel sheet groove 19 along the circumference, and the steel sheet groove 19 is used to install and fix the steel sheet of the stator 9. The steel sheet is installed in a sealing manner with the steel sheet groove 19. The inner surface of the steel sheet groove 19 is provided with a continuously arranged air guide groove 20, and the head and tail of the air guide groove 20 are spaced apart. A cooling gas inlet 21 is provided at the front end position of the shell 8 corresponding to the air guide groove 20, and an exhaust groove 22 for discharging the gas to one side of the stator 9 is provided at the tail end position of the air guide groove 20 on the inner surface of the shell 8. A cooling gas outlet 23 is provided on the other side of the shell 8 of the stator 9. The cooling gas inlet 21 and the cooling gas outlet 23 are respectively connected to the interstage connecting pipe 13 through pipelines;

[0035] A boss 24 is provided on the side wall of the bearing seat 11 close to the motor cavity, and a plurality of heat dissipation channels 25 are provided along the circumference of the boss 24 to connect the inner hole of the bearing seat 11 with the motor cavity. The cooling gas in the motor cavity enters the inner hole of the bearing seat 11 through the heat dissipation channel 25 to cool the radial air bearing 12.

[0036] The condenser 15 is used to cool the high-temperature gas discharged from the secondary gas outlet 7 and convert the gas into liquid.

[0037] The first expansion valve 16 and the second expansion valve 18 are used to atomize the liquid discharged from the condenser 15 by adjusting the opening size.

[0038] The evaporator 17 is used to gasify the mist discharged from the first expansion valve 16 and cool the surrounding air to blow out cold wind, thereby achieving air conditioning and refrigeration.

[0039] The interstage cooling pipe 14 performs heat exchange in the interstage connecting pipe 13 , and the mist discharged from the second expansion valve 18 in the interstage cooling pipe 14 is gasified, and the surrounding air is cooled to cool the gas in the interstage connecting pipe 13 .

[0040] The interstage cooling pipe 14 is arranged inside the interstage connecting pipe 13 in a zigzag, coil or labyrinth shape to enhance the effect of heat exchange and make the heat exchange more sufficient.

[0041] The steel sheet and the edge of the steel sheet groove 19 are sealed by sealant to prevent the cooling gas from being directly discharged from the edge of the steel sheet groove 19, thereby ensuring that the cooling gas travels along the air guide groove 20 and improving the cooling effect.

[0042] The shape of the air guide groove 20 includes a continuously arranged S-shape, W-shape or spiral shape commonly used in the field, which can extend the travel distance of the cooling gas and improve the cooling effect.

[0043] Working principle:

[0044] During operation, the motor 1 drives the primary compression pump head 2 and the secondary compression pump head 3 to operate at the same time. The temperature of the high-pressure gas discharged from the secondary air outlet 7 of the secondary compression pump head 3 is about 42°C. After these gases enter the condenser 15, the high-temperature gas is cooled to turn the gas into liquid. The temperature of the liquid discharged from the liquid outlet of the condenser 15 is about 30°C. A part of these liquids are atomized by the first expansion valve 16 and enter the evaporator 17. The evaporator 17 vaporizes the mist and cools the surrounding air to blow out cold wind to achieve air conditioning and refrigeration. The temperature of the gas discharged from the evaporator 17 is about 35°C. These gases then enter the primary air inlet 4 of the primary compression pump head 2; another part of the liquid discharged from the liquid outlet of the condenser 15 is atomized by the second expansion valve 18 and enters the interstage cooling pipe 14, and exchanges heat with the gas in the interstage connecting pipe 13 to cool the surrounding air and cool the gas in the interstage connecting pipe 13, thereby reducing the temperature of the gas entering the secondary air inlet 6 to about 37°C, and the temperature of the gas discharged from the interstage cooling pipe 14 to about 35°C, and these gases then enter the primary air inlet 4 of the primary compression pump head 2; after the primary compression pump head 2 undergoes primary pressurization, the temperature of the gas rises to about 40°C, and then is discharged from the primary air outlet 5 to the interstage connecting pipe 13, and after being cooled by the interstage cooling pipe 14, it enters the secondary air inlet 6 at about 37°C, and after undergoing secondary pressurization in the secondary compression pump head 3, the temperature of the high-pressure gas discharged from the secondary air outlet 7 is about 42°C, thereby forming a closed-loop circulation of the interstage cooling system of the two-stage gas compressor.

[0045] The cooling gas in the interstage connecting pipe 13 can also enter the air guide groove 20 through the pipeline via the cooling gas inlet 21. Since the steel sheet and the steel sheet groove 19 are sealed and installed, and the edges of the steel sheet and the steel sheet groove 19 are sealed by sealant, the air guide groove 20 can form an independent air guide channel, and the cooling gas travels along the air guide groove 20 to directly cool the steel sheet of the stator 9; the cooling gas in the air guide groove 20 is discharged to the motor cavity on one side of the stator 9 through the exhaust groove 22, which can cool the stator winding package on this side, and then discharged to the motor cavity on the other side of the stator 9 through the gap between the stator 9 and the main shaft 10, so as to cool the stator winding package on the other side; at the same time, the cooling gas in the motor cavity can enter the inner hole of the bearing seat 11 through a number of heat dissipation channels 25, cool the radial air bearing 12, and carry and discharge the heat generated by the radial air bearing 12 during operation, and finally discharge it to the interstage connecting pipe 13 through the cooling gas outlet 23. In this way, not only can the steel sheets and the windings on both sides of the stator 9 be directly cooled, with good cooling effect, but also the heat inside the radial air bearing 12 and the motor cavity can be carried away and discharged in time, avoiding the accumulation of heat in the motor cavity, protecting the motor 1, and extending the service life of the radial air bearing 12 and the motor 1.

[0046] The above specific implementation manner cannot be used as a limitation on the protection scope of the present invention. For those skilled in the art, any substitution, improvement or change made to the implementation manner of the present invention falls within the protection scope of the present invention.

[0047] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

Claims

1. A sufficient cooling system for a gas compressor, comprising a motor, the motor end is connected to a primary compression pump head and a secondary compression pump head, the primary air outlet of the primary compression pump head and the secondary air inlet of the secondary compression pump head are connected through an interstage connecting pipe, the motor comprises a housing, a stator and a main shaft are arranged in the housing, both ends of the main shaft are supported by a bearing seat, a radial air bearing is arranged between the bearing seat and the main shaft, and the characteristics are: An interstage cooling pipe is arranged in the interstage connecting pipe, and the interstage cooling pipe is connected to the interstage cooling system, and the interstage cooling system includes a condenser connected to the secondary air outlet of the secondary compression pump head through a pipeline, a branch of the liquid outlet of the condenser is connected to the inlet of the evaporator through a first expansion valve, the air outlet of the evaporator is connected to the primary air inlet of the primary compression pump head through a pipeline, another branch of the liquid outlet of the condenser is connected to the inlet of the interstage cooling pipe through a second expansion valve, and the air outlet of the interstage cooling pipe is connected to the primary air inlet of the primary compression pump head through a pipeline; The inner surface of the shell is provided with steel sheet grooves along the circumference, and the steel sheet grooves are used to install and fix the steel sheets of the stator. The steel sheets are installed in a sealed manner in the steel sheet grooves. The inner surface of the steel sheet grooves is provided with continuously arranged air guide grooves, and the head and tail of the air guide grooves are spaced apart. A cooling gas inlet is provided at the front end position of the shell corresponding to the air guide groove, and an exhaust groove for discharging the gas to one side of the stator is provided at the tail end position of the air guide groove on the inner surface of the shell. A cooling gas outlet is provided on the other shell of the stator, and the cooling gas inlet and the cooling gas outlet are respectively connected to the interstage connecting pipe through pipelines; A boss is provided on the side wall of the bearing seat close to the motor cavity, and a plurality of heat dissipation channels are provided along the circumference of the boss to connect the inner hole of the bearing seat with the motor cavity. The cooling gas in the motor cavity enters the inner hole of the bearing seat through the heat dissipation channel to cool the radial air bearing.

2. A sufficient cooling system for a gas compressor according to claim 1, characterized in that: The condenser is used to cool the high-temperature gas discharged from the secondary gas outlet and convert the gas into liquid.

3. A sufficient cooling system for a gas compressor according to claim 2, characterized in that: The first expansion valve and the second expansion valve are used to atomize the liquid discharged from the condenser.

4. A sufficient cooling system for a gas compressor according to claim 3, characterized in that: The evaporator is used to gasify the mist discharged from the first expansion valve and cool the surrounding air to blow out cold wind.

5. A sufficient cooling system for a gas compressor according to claim 3, characterized in that: The interstage cooling pipe performs heat exchange in the interstage connecting pipe, and the mist discharged from the second expansion valve in the interstage cooling pipe is gasified, and the surrounding air is cooled to cool the gas in the interstage connecting pipe.

6. A sufficient cooling system for a gas compressor according to claim 1, characterized in that: The interstage cooling pipe is arranged inside the interstage connecting pipe in a zigzag shape, a coil shape or a labyrinth shape.

7. A sufficient cooling system for a gas compressor according to claim 1, characterized in that: The steel sheet and the edge of the steel sheet groove are sealed by sealant.

8. A sufficient cooling system for a gas compressor according to claim 1, characterized in that: The shape of the air guide grooves includes a continuously arranged S-shape, a W-shape or a spiral shape.

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