Gas phase temperature measurement device at the exhaust end of liquid injection screw compressor

Abstract

The present invention discloses a gas-phase temperature measuring device at the exhaust end of a liquid-spraying screw compressor. The liquid-spraying screw compressor comprises a compressor body and an outlet short circuit connected to the exhaust port of the compressor body. The gas-phase temperature measuring device at the exhaust end of the liquid-spraying screw compressor comprises a temperature measuring element, a sleeve, a gas-liquid separation component and a sealing structure. The sleeve passes through the side wall of the outlet short circuit, the bottom of the sleeve extends into the central hole of the outlet short circuit, and the sleeve and the outlet short circuit are connected to each other. The gas-liquid separation component is fixed to the bottom of the sleeve, the sealing structure is arranged at the top of the sleeve, and a temperature measuring cavity is formed between the gas-liquid separation component and the sealing structure. The gas-liquid separation component is used to block the liquid phase medium and allow the gas phase medium to enter the temperature measuring cavity through the gas-liquid separation component. The temperature measuring element is inserted into the temperature measuring cavity through the sealing structure. The present invention can accurately measure the temperature of the gas phase medium at the exhaust end of the liquid-spraying screw compressor.

Description

Technical Field

[0001] The present invention relates to a liquid injection screw compressor. Background Art

[0002] Screw compressors are an important type of rotary positive displacement boosting equipment in the field of oil refining and chemical industry. In order to apply screw compressors to higher pressure ratio processes and give full play to the advantages of the equipment, most process gas screw compressors are operated in a liquid injection mode. On the one hand, the temperature rise during the compression process is controlled to prevent damage to the unit. On the other hand, the sealing effect of the gap between the yin and yang rotors and the shell can be improved to improve the volumetric efficiency.

[0003] The characteristics of the process gas screw compressor determine that its back-end process flow is mostly gas-liquid two-phase under most conditions, which is a working condition that the most commonly used reciprocating compressors and centrifugal compressors in the oil refining and chemical processes are not suitable. Screw compressors usually have a high speed, so the residence time of the process medium in the compressor compression chamber is very short. This leads to that under most working conditions, when the temperature of the medium at the end of compression is controlled by liquid injection, the heat exchange of the gas-liquid two-phase medium inside the compressor is not fully completed, that is, there is a temperature difference between the gas and liquid two-phase medium at the outlet of the compressor, and sufficient heat exchange is completed in the outlet and subsequent pipelines. In the process medium inside the compressor, the volume proportion of the liquid phase medium is much smaller than that of the gas phase medium, and the thermal expansion of the rotor is mainly affected by the gas phase temperature. Although the volume proportion of the liquid phase medium in the process medium is small, the liquid flow rate has a significant impact on the exhaust temperature and the volumetric efficiency of the compressor.

[0004] In the actual operation of the liquid injection screw compressor, the gas phase temperature measurement at the exhaust end is crucial to ensure the safe operation of the entire system. Inaccurate temperature measurement will affect the service life of the compressor and even cause damage to the entire compressor, making the compressor unable to operate. The existing temperature measurement device cannot accurately measure the temperature of the gas phase medium at the exhaust end of the liquid injection screw compressor due to the interference of the liquid phase medium. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor, which can accurately measure the temperature of the gas phase medium at the exhaust end of the liquid injection screw compressor and has a simple structure.

[0006] The present invention provides a gas-phase temperature measuring device at the exhaust end of a liquid-spraying screw compressor. The liquid-spraying screw compressor comprises a compressor body and an outlet short circuit connected to the exhaust port of the compressor body. The gas-phase temperature measuring device at the exhaust end of the liquid-spraying screw compressor comprises a temperature measuring element, a sleeve, a gas-liquid separation component and a sealing structure; the sleeve passes through the side wall of the outlet short circuit, the bottom of the sleeve extends into the central hole of the outlet short circuit, and the sleeve and the outlet short circuit are connected to each other; the gas-liquid separation component is fixed to the bottom of the sleeve, the sealing structure is arranged at the top of the sleeve to seal the opening at the top of the sleeve, a temperature measuring cavity is formed between the gas-liquid separation component and the sealing structure, the gas-liquid separation component is used to block the liquid phase medium and allow the gas phase medium to enter the temperature measuring cavity through the gas-liquid separation component; the temperature measuring element is inserted into the temperature measuring cavity through the sealing structure.

[0007] The present invention has at least the following advantages:

[0008] 1. The present invention sets a temperature measuring device at the outlet short-circuit of the compressor exhaust end. The temperature measuring device first performs liquid phase separation on the gas-liquid two-phase mixture discharged from the compressor exhaust port, and then measures the temperature of the gas phase medium by the temperature measuring element, thereby avoiding the interference of the liquid phase medium on the temperature measuring element, achieving the purpose of accurately measuring the temperature of the high-temperature gas phase medium under the gas-liquid two-phase flow state, and ensuring the stable and efficient operation of the process gas liquid injection screw compressor;

[0009] 2. The present invention has a simple structure and is easy to repair and maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The overall structural schematic diagram of a liquid-injected screw compressor using a gas phase temperature measuring device according to an embodiment of the present invention is shown.

[0011] Figure 2 A schematic diagram of a compressor body is shown.

[0012] Figure 3 A schematic diagram of a device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to an embodiment of the present invention is shown.

[0013] Figure 4 A structural schematic diagram of an embodiment of a gas-liquid separation component is shown. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings.

[0015] Figure 1 FIG. 1 shows an overall structural schematic diagram of a liquid injection screw compressor 500 using a gas phase temperature measuring device 100 according to an embodiment of the present invention. Figure 2 shows a schematic diagram of the compressor body. Figure 1 and Figure 2 The liquid injection screw compressor includes a compressor body 51 , an inlet short circuit 52 connected to an air inlet 511 of the compressor body 51 , an outlet short circuit 53 connected to an exhaust port 512 of the compressor body 51 , and an inlet liquid injection pipeline 54 connected to the inlet short circuit 52 .

[0016] In this embodiment, the inlet liquid injection pipeline 54 is welded to the inlet short circuit 52, and a first flow regulating valve 61 is provided on the inlet liquid injection pipeline 54 to adjust the flow rate of the inlet liquid injection. During the operation of the liquid injection screw compressor 500, in order to prevent the compressor rotor from biting with the inner wall of the shell due to excessive gas phase temperature, liquid is sprayed into the inlet short circuit 52 through the inlet liquid injection pipeline 54, which can not only cool the rotor, but also seal the compressor.

[0017] See also Figure 3 The gas phase temperature measuring device 100 of the exhaust end of a liquid injection screw compressor according to an embodiment of the present invention comprises a temperature measuring element 1, a sleeve 2, a gas-liquid separation component 3 and a sealing structure.

[0018] The sleeve 2 passes through the side wall of the outlet short circuit 53, and the bottom of the sleeve 2 extends into the central hole 530 of the outlet short circuit 53, and the sleeve 2 and the outlet short circuit 53 are connected to each other, and the connection method can be welding, etc. The gas-liquid separation component 3 is fixed to the bottom of the sleeve 2, and the sealing structure is arranged on the top of the sleeve 2 to seal the opening at the top of the sleeve 2. A temperature measurement cavity 22 is formed between the gas-liquid separation component 3 and the sealing structure. The gas-liquid separation component 3 is used to block the liquid phase medium and allow the gas phase medium to enter the temperature measurement cavity 22 through the gas-liquid separation component 3. The temperature measurement element 1 is inserted into the temperature measurement cavity 22 through the sealing structure.

[0019] In this embodiment, the temperature measuring element 1 is connected to the sealing structure to fix the temperature measuring element 1. The sealing structure includes a top cover 4, and the top cover 4 is welded to the top end of the sleeve 2. The temperature measuring element 1 is inserted into the temperature measuring cavity 22 through the top cover 4. Further, the top cover 4 is provided with a threaded through hole 40, and the temperature measuring element 1 is inserted into the temperature measuring cavity 22 through the threaded through hole 40, and the temperature measuring element 1 is spirally connected to the threaded through hole 40.

[0020] In this embodiment, the sleeve 2 vertically passes through the side wall of the outlet short circuit 53, the bottom end surface 2a of the sleeve 2 is an inclined surface, and the bottom end of the sleeve 2 faces the flow direction of the gas-liquid two-phase flow. Figure 3 The arrow direction in is the flow direction of the gas-liquid two-phase flow in the outlet short-circuit 53. The angle θ between the inclined surface 2a and the axis of the outlet short-circuit 53 is 15° to 60°. The gas-liquid separation component 3 is located in the sleeve 2 and close to the bottom end surface of the sleeve. The depth H of the sleeve 2 inserted into the outlet short-circuit 53 is related to the diameter D of the outlet short-circuit 53. The larger D is, the larger H is.

[0021] Preferably, the sleeve 2 is connected to the inlet short circuit 52 through the drainage pipeline 7. The drainage pipeline 7 can form a pressure difference in the sleeve 2 on the one hand, which is conducive to the circulation of airflow, and on the other hand, it can discharge the accumulated liquid in the sleeve 2. The drainage pipeline 7 is provided with a second flow regulating valve 62 to control the amount of gas diverted from the drainage pipeline. In the example shown in the figure, the side wall of the sleeve 2 is provided with a drainage short circuit 21 that is connected to the temperature measurement cavity 22 of the sleeve 2, and the drainage short circuit 21 and the guide pipeline 7 are connected to each other.

[0022] In this embodiment, the temperature measuring element 1 is a thermal resistor, and the gas-liquid separation component 3 is a wire mesh component, but it is not limited thereto. The gas-liquid separation component 3 can also be a baffle, a perforated plate, or other forms of filter mesh. The temperature measuring element 1 is connected to the data acquisition computer 8 via a signal data line 11 to send the detected temperature measurement result to the data acquisition computer 8.

[0023] like Figure 4 As shown, the wire mesh component includes a shell 31 and a metal wire mesh (not shown in the figure), and the shell 31 is welded to the sleeve 2. The shell 31 includes a cylinder 310, a first mesh plate 311 and a second mesh plate 312. The first mesh plate 311 is connected to the top end of the cylinder 310, and the second mesh plate 312 is connected to the bottom end of the cylinder 310. The cylinder 310, the first mesh plate 311 and the second mesh plate 312 jointly define an inner cavity, and the aforementioned metal wire mesh is arranged in the inner cavity.

[0024] Optionally, the mesh diameters of the first mesh plate 311 and the second mesh plate 312 are 1 mm, and the mesh diameter of the metal wire mesh is 4 mm-5 mm.

[0025] After the gas-liquid two-phase mixture is discharged from the exhaust port 512 of the compressor to the outlet short circuit 53, it will collide with the casing 2 when passing through the bottom end surface 2a of the casing 2. Since the density of the gas-phase medium is much smaller than the density of the liquid-phase medium, the gas-phase medium will change its movement direction after colliding with the casing 2 and enter the casing 2 along the inclined surface. After the liquid-phase medium collides with the casing 2, a part of the liquid-phase medium will be captured by the wall surface of the casing 2, and the remaining liquid-phase medium that has not been captured due to no collision will collide with the filaments of the metal wire mesh when passing through the wire mesh component and be attached to the surface of the filaments, thereby realizing secondary separation of the liquid-phase medium, making the external environment of the temperature measuring element 1 a pure gas-phase environment, avoiding the interference of the liquid-phase medium on the temperature measuring element 1, and thus enabling the temperature measuring element 1 to accurately measure the temperature of the gas-phase medium.

[0026] The above description is only a preferred embodiment of the invention and is not intended to limit the invention. Although the invention is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the invention shall be included in the protection scope of the invention.

Claims

1. A device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor, wherein the liquid injection screw compressor comprises a compressor body and an outlet short circuit connected to the exhaust port of the compressor body; characterized in that: The gas phase temperature measuring device at the exhaust end of the liquid injection screw compressor comprises a temperature measuring element, a sleeve, a gas-liquid separation component and a sealing structure; The sleeve passes through the side wall of the outlet short-circuit, the bottom of the sleeve extends into the central hole of the outlet short-circuit, and the sleeve and the outlet short-circuit are connected to each other; The gas-liquid separation component is fixed to the bottom of the sleeve, the sealing structure is arranged at the top of the sleeve to seal the opening at the top of the sleeve, a temperature measurement cavity is formed between the gas-liquid separation component and the sealing structure, and the gas-liquid separation component is used to block the liquid phase medium and allow the gas phase medium to enter the temperature measurement cavity through the gas-liquid separation component; The gas-liquid separation component is a wire mesh component, and the wire mesh component is fixedly connected or detachably connected to the sleeve; the wire mesh component includes a shell and a metal wire mesh, and the shell is welded to the sleeve; the shell includes a cylinder, a first mesh plate and a second mesh plate; the first mesh plate is connected to the top end of the cylinder, and the second mesh plate is connected to the bottom end of the cylinder, and the cylinder, the first mesh plate and the second mesh plate jointly define an inner cavity; the metal wire mesh is arranged in the inner cavity; The temperature measuring element is inserted into the temperature measuring cavity through the sealing structure; The liquid injection screw compressor comprises an inlet short circuit connected to the air inlet of the compressor body; the temperature measuring cavity of the sleeve is connected to the inlet short circuit through a drainage pipeline.

2. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to claim 1, characterized in that: The sleeve vertically passes through the side wall of the outlet short circuit, the bottom end surface of the sleeve is an inclined surface, and the bottom end of the sleeve faces the flow direction of the gas-liquid two-phase flow.

3. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to claim 2, characterized in that: The angle θ between the inclined surface and the axis of the outlet short circuit is 15° to 60°.

4. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to claim 1, characterized in that: A flow regulating valve is arranged on the drainage pipeline.

5. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to claim 1, characterized in that: The temperature measuring element is connected to the sealing structure.

6. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to claim 1, wherein the sealing structure comprises a top cover, and the top cover is welded to the top end of the sleeve; The top cover is provided with a threaded through hole, the temperature measuring element is inserted into the temperature measuring cavity through the threaded through hole, and the temperature measuring element is screwedly connected to the threaded through hole.

7. The device for measuring the gas phase temperature at the exhaust end of a liquid injection screw compressor according to any one of claims 1 to 6, characterized in that: The temperature measuring element is a thermal resistor.

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