Oil mist treatment system of oil-free screw compressor

Abstract

The utility model discloses an oil mist treatment system of an oil-free screw compressor, and belongs to the field of screw compressors. The device comprises a filter, a pressure reducing valve, a vacuum generator and an oil mist separator, an air inlet of the filter is connected with an exhaust port pipeline of the compressor unit, an air outlet of the filter is connected with an air inlet of the pressure reducing valve through a first pipeline, an air outlet of the pressure reducing valve is connected with an air supply port of the vacuum generator through a second pipeline, and a vacuum port of the vacuum generator is connected with a breathing port of the gearbox through a third pipeline. An exhaust port of the vacuum generator is connected with an air inlet of the oil mist separator through a fourth pipeline. The structure of the compressor is improved, the oil mist problem of the gearbox of the compressor can be solved, the structure is simple, external energy is not needed to suck oil mist or the oil mist separator is not needed to be specially improved, and the cost is low.

Description

Technical Field

[0001] The utility model belongs to the field of screw compressors, and more specifically relates to an oil mist treatment system for an oil-free screw compressor. Background Art

[0002] The rotating parts of the oil-free screw compressor unit need to be lubricated during operation, and the lubrication process is as follows. The lubricating oil in the compressor oil tank is pumped to the oil cooler for cooling through a screw pump, and then filtered through a filter to enter the compressor's gearbox and various bearing lubrication points. In the process of lubricating and cooling the high-speed rotating gears and bearings, the lubricating oil will evaporate at high temperature, thereby generating a large amount of oil mist, which puts the compressor gearbox and the inside of the oil tank in a positive pressure state. However, if the compressor gearbox is in this positive pressure state for a long time, the risk of leakage at the shaft seal will increase, and once the oil mist leaks out, it will bring safety hazards and environmental pollution, and have a serious impact on production and the physical and mental health of the staff. Therefore, it is necessary to export and treat the oil mist in the gearbox. In response to this problem, corresponding solutions have also been designed in the prior art.

[0003] For example, the Chinese patent application number is CN201410177291.1, and the publication date is November 4, 2015. The patent document discloses a compressor with an oil mist separation system, including a housing, a gearbox, an oil mist separator and a transmission system. The housing is provided with a return air port and an exhaust port. The gearbox is arranged in the housing, and a partition is arranged in the gearbox to separate the space in the gearbox into a rear chamber and a front chamber separated from each other, and the rear chamber is connected to the return air port. The oil mist separator is arranged in the rear chamber, and the oil mist separator is provided with an oil outlet, an inlet and an outlet, and the inlet and the oil outlet are connected to the front chamber, and the outlet is connected to the rear chamber. The transmission system is arranged in the front chamber, and the rear chamber is connected to the air inlet end of the impeller. This scheme effectively balances the pressure between the rear chamber and the front chamber and the air inlet end of the impeller, and improves the oil mist separation efficiency of the refrigerant.

[0004] For example, the Chinese patent application number is: CN202311033513.8, and the patent document with the publication date of November 17, 2023 discloses an oil mist collector and an oil mist recovery method for a compressor gearbox, which includes an air inlet pipe and an exhaust mechanism, and its structural features are: it also includes a cooler shell, a cooling core, a separation cylinder, a separation inner core, a filter screen and an oil return pipe, the cooling core is provided with several vertical cooling pipes, and the cooling core is installed in the cooler shell; the air inlet pipe is fixed to the bottom of the cooler shell, and a circle of siphon grooves is fixed on the top outer wall of the cooler shell, and an oil drain port is provided at the bottom of the siphon groove, which is connected to the air inlet pipe through the oil return pipe; the separation cylinder is a cylindrical structure, the bottom of the separation cylinder is fixed on the siphon groove, and the exhaust mechanism is fixed on the top of the separation cylinder; the separation inner core is fixed in the separation cylinder, the filter screen is wrapped around the outer wall of the separation inner core, and the entrance of the siphon groove is located between the outer wall of the filter screen and the inner wall of the separation cylinder. This solution has high oil mist separation efficiency and can ensure that the internal pressure of the gearbox is negative.

[0005] However, in the above two solutions, a special oil mist separator is designed directly for the gear box, which is either relatively complex in structure or requires a special device for sucking the gear box oil mist that needs external energy to start, which is relatively costly. Summary of the invention

[0006] 1. Problems to be solved

[0007] In view of the problem that when treating the oil mist in the compressor gearbox in the prior art, the structure is relatively complicated, or external energy is required to start the oil mist suction device, resulting in high cost, the utility model provides an oil mist treatment system for an oil-free screw compressor, which is improved in combination with the structure of the compressor itself and can solve the oil mist problem of the compressor gearbox. It has a simple structure, does not require external energy to suck the oil mist or special improvements to the oil mist separator, and has low cost.

[0008] 2. Technical solution

[0009] To solve the above problems, the utility model adopts the following technical solutions.

[0010] An oil mist treatment system for an oil-free screw compressor comprises a filter, a pressure reducing valve, a vacuum generator and an oil mist separator; the air inlet of the filter is connected to the exhaust pipe of the compressor unit, the air outlet is connected to the air inlet of the pressure reducing valve through a pipe one, the air outlet of the pressure reducing valve is connected to the air supply port of the vacuum generator through a pipe two, the vacuum port of the vacuum generator is connected to the breathing port of a gear box through a pipe three, and the exhaust port of the vacuum generator is connected to the air inlet of the oil mist separator through a pipe four.

[0011] As a further improvement of the technical solution, the vacuum port of the vacuum generator is connected to the breathing port of the gear box through one of the three-way joints of the pipeline, and the other joint of the three-way joint is connected to the breathing port of the gear box through a mist exhaust pipe, and a negative pressure gauge is installed on the mist exhaust pipe.

[0012] As a further improvement of the technical solution, the pressure reducing valve is fixedly mounted on bracket one.

[0013] As a further improvement of the technical solution, the oil mist separator is fixedly mounted on bracket two.

[0014] As a further improvement of the technical solution, the oil discharge port of the oil mist separator is connected to the oil tank through an oil return pipe.

[0015] As a further improvement of the technical solution, the pressure reducing valve is a filtering pressure reducing valve.

[0016] As a further improvement of the technical solution, the filter is a Y-type filter.

[0017] As a further improvement of the technical solution, the pipeline one, pipeline two, pipeline three and pipeline four are connected to the remaining components through a compression fitting.

[0018] As a further improvement of the technical solution, the gear box is equipped with a positive pressure gauge for detecting the internal pressure of the gear box.

[0019] As a further improvement of the technical solution, a pressure regulating knob is provided on the pressure reducing valve.

[0020] 3. Beneficial effects

[0021] Compared with the prior art, the beneficial effects of the utility model are:

[0022] (1) The utility model is an oil mist treatment system for an oil-free screw compressor, which draws compressed gas from the exhaust pipe of the compressor unit, filters it and then enters the pressure reducing valve to reduce the pressure. The reduced-pressure gas enters the vacuum generator. When the pressure at the air supply port of the vacuum generator is higher than a certain value, the gas in the negative pressure chamber inside the vacuum generator is sucked away, so that the cavity forms a very low vacuum degree. Then, under the action of the pressure difference, the oil mist in the gear box enters the vacuum generator, mixes with the compressed gas and enters the oil mist separator for oil and gas separation, thereby solving the oil mist problem in the gear box. This method has no requirements for the structure of the oil mist separator, and the oil mist can be absorbed by introducing the compressed gas in the compressor unit. Compared with the existing technology, it is simpler and effectively reduces the cost of treating the gear box oil mist.

[0023] (2) The utility model is an oil mist treatment system for an oil-free screw compressor, which adopts a dual filtering structure of a Y-type filter and a filter pressure reducing valve to filter tiny solid particles and moisture in the compressed gas respectively, thereby improving the purity of the compressed gas and ensuring the normal operation of adjusting the pressure difference to absorb the oil mist of the gear box after the compressed gas enters the vacuum generator;

[0024] (3) The utility model provides an oil mist treatment system for an oil-free screw compressor. By installing a negative pressure gauge, the vacuum degree of the gear box can be monitored in real time, making it convenient for the staff to adjust the pressure reducing valve. By installing a positive pressure gauge on the gear box to detect the internal pressure of the gear box, it is convenient for the staff to selectively or automatically select the start time of the oil mist treatment system according to the internal pressure of the gear box or through the central control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a main structural schematic diagram of the utility model.

[0026] Figure 2 yes Figure 1 Top view of the .

[0027] Figure 3 It is a schematic diagram of the working principle of the utility model;

[0028] In the figure: 1. filter; 2. pipeline one; 3. pressure reducing valve; 4. bracket one; 5. vacuum generator; 6. bracket two; 7. oil mist separator; 8. three-way joint; 9. negative pressure gauge; 10. pipeline two; 11. pipeline three; 12. pipeline four. DETAILED DESCRIPTION

[0029] Exemplary embodiments of the present invention are described in detail below. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to implement the present invention, it should be understood that other embodiments may be implemented and various changes may be made to the present invention without departing from the spirit and scope of the present invention. The more detailed description of the embodiments of the present invention below is not intended to limit the scope of the claimed present invention, but is merely for illustration and does not limit the description of the features and characteristics of the present invention, in order to propose the best way to perform the present invention, and is sufficient to enable those skilled in the art to implement the present invention. Therefore, the scope of the present invention is limited only by the appended claims.

[0030] Example 1

[0031] An oil mist treatment system for an oil-free screw compressor is applicable to the oil-free screw compressor and is used to treat leakage problems that may be caused by a large amount of oil mist inside the compressor gearbox. The specific structure and working principle thereof are described in detail below.

[0032] like Figure 1 and Figure 2 As shown, the system includes a filter 1 , a pressure reducing valve 3 , a vacuum generator 5 and an oil mist separator 7 .

[0033] The air inlet of the filter 1 is connected to the exhaust pipe of the compressor unit, the air outlet is connected to one end of the pipe 1 2 through a ferrule joint, and the other end of the pipe 1 2 is connected to the air inlet of the pressure reducing valve 3 through a ferrule joint. The air outlet of the pressure reducing valve 3 is connected to one end of the pipe 2 10 through a ferrule joint, and the other end of the pipe 2 10 is connected to the air supply port of the vacuum generator 5 through a ferrule joint.

[0034] The vacuum port of the vacuum generator 5 is connected to one end of the pipe three 11 through a ferrule joint, and the other end of the pipe three 11 is connected to one of the joints of the three-way joint 8 through a ferrule joint. The other joint of the three-way joint 8 is connected to the breathing port of the gear box through a mist exhaust pipe, and the mist exhaust pipe is equipped with a negative pressure gauge 9. The exhaust port of the vacuum generator 5 is connected to one end of the pipe four 12 through a ferrule joint, and the other end of the pipe four 12 is connected to the air inlet of the oil mist separator 7 through a ferrule joint. The oil outlet of the oil mist separator 7 is connected to the oil tank through an oil return pipe.

[0035] In addition, the pressure reducing valve 3 is fixedly mounted on the bracket 1 4, and the oil mist separator 7 is fixedly mounted on the bracket 2 6, and the bracket 1 4 and the bracket 2 6 respectively form a support for the pressure reducing valve 3 and the oil mist separator 7. Specifically, a gasket is fixedly mounted on the bracket 1 4 by bolts and nuts, and the gasket is also fixedly connected to the pressure reducing valve 3 by bolts and nuts. The connection structure between the bracket 2 6 and the oil mist separator 7 can adopt the above structure, or a structure in which a stud with an external thread is provided under the oil mist separator 7, and a threaded hole is provided on the bracket 2 6 to achieve a threaded fixed connection.

[0036] In this embodiment, the pressure reducing valve 3 is a filter pressure reducing valve, and the filter 1 is a Y-type filter. The Y-type filter filters out tiny solid particles in the compressed gas, and the filter pressure reducing valve filters out moisture in the compressed gas while reducing the pressure of the compressed gas, ensuring that the compressed gas enters the vacuum generator 6 and adjusts the pressure difference to absorb the gear box oil mist normally.

[0037] The oil mist treatment system of this embodiment is installed on the base of the oil-free screw compressor. Figure 3As shown, when the system is working, a compressed gas is introduced from the exhaust pipe of the unit into the Y-type filter for filtration, mainly filtering out some tiny solid particles. Then the filtered compressed gas enters the filter pressure reducing valve for decompression and re-filtration, mainly filtering out the moisture in the gas. Then the decompressed gas enters the interior from the air supply port of the vacuum generator 6, until the pressure of the air supply port is higher than a certain value, it will suck away the gas in the negative pressure chamber inside the vacuum generator 6, so that the cavity forms a very low vacuum degree. Since the vacuum port of the vacuum generator 6 is connected to the breathing port of the gear box, the oil mist in the gear box will enter the vacuum generator 6 along the pipeline, and then enter the oil mist separator 7 from the exhaust port for oil and gas separation, and the separated lubricating oil returns to the oil tank from the return oil pipe below the oil mist separator 7. This method has no requirements for the structure of the oil mist separator 7, and the oil mist can be absorbed by introducing the compressed gas in the compressor unit. Compared with the existing technology, it is simpler and effectively reduces the processing cost of the gear box oil mist.

[0038] In this embodiment, the filter pressure reducing valve is adjustable and is equipped with a pressure regulating knob. By rotating the knob, the vacuum degree of the gear box is adjusted to -0.02Pa, that is, 0.02Pa is displayed on the negative pressure gauge 9, so that the inside of the gear box is in a slightly negative pressure state. At the same time, a positive pressure gauge for detecting the internal pressure of the gear box is installed on the gear box, which is convenient for the staff to selectively or automatically select the start time of the oil mist treatment system according to the internal pressure of the gear box or through the central control system.

[0039] In summary, an oil-free screw compressor and its oil mist treatment system of this embodiment, combined with the improvement of the compressor structure itself, can solve the oil mist problem of the compressor gearbox. It has a simple structure, does not require external energy to extract the oil mist or special improvements to the oil mist separator, and has a low cost.

Claims

1. An oil mist treatment system for an oil-free screw compressor, characterized in that: The invention comprises a filter (1), a pressure reducing valve (3), a vacuum generator (5) and an oil mist separator (7); the air inlet of the filter (1) is connected to the exhaust pipe of the compressor unit, the air outlet is connected to the air inlet of the pressure reducing valve (3) through a pipe 1 (2), the air outlet of the pressure reducing valve (3) is connected to the air supply port of the vacuum generator (5) through a pipe 2 (10), the vacuum port of the vacuum generator (5) is connected to the breathing port of the gear box through a pipe 3 (11), and the exhaust port of the vacuum generator (5) is connected to the air inlet of the oil mist separator (7) through a pipe 4 (12).

2. The oil mist treatment system for an oil-free screw compressor according to claim 1, characterized in that: The vacuum port of the vacuum generator (5) is connected to one of the joints of the three-way joint (8) through a pipe three (11), and the other joint of the three-way joint (8) is connected to the breathing port of the gear box through a mist exhaust pipe, and a negative pressure gauge (9) is installed on the mist exhaust pipe.

3. The oil mist treatment system for an oil-free screw compressor according to claim 2, characterized in that: The pressure reducing valve (3) is fixedly mounted on bracket one (4).

4. The oil mist treatment system for an oil-free screw compressor according to claim 3, characterized in that: The oil mist separator (7) is fixedly mounted on the second bracket (6).

5. The oil mist treatment system for an oil-free screw compressor according to claim 4, characterized in that: The oil discharge port of the oil mist separator (7) is connected to the oil tank via an oil return pipe.

6. An oil mist treatment system for an oil-free screw compressor according to any one of claims 1 to 5, characterized in that: The pressure reducing valve (3) is a filtering pressure reducing valve.

7. The oil mist treatment system for an oil-free screw compressor according to claim 6, characterized in that: The filter (1) is a Y-type filter.

8. An oil mist treatment system for an oil-free screw compressor according to any one of claims 1 to 5, characterized in that: The pipeline one (2), pipeline two (10), pipeline three (11) and pipeline four (12) are connected with other components through ferrule joints.

9. An oil mist treatment system for an oil-free screw compressor according to any one of claims 1 to 5, characterized in that: The gear box is equipped with a positive pressure gauge for detecting the internal pressure of the gear box.

10. An oil mist treatment system for an oil-free screw compressor according to any one of claims 1 to 5, characterized in that: The pressure reducing valve (3) is provided with a pressure regulating knob.

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