A turbine vacuum pump with an electric anti-surge valve

Abstract

This utility model relates to the field of anti-surge control technology for turbine vacuum pumps, and discloses a turbine vacuum pump with an electric anti-surge valve. The pump includes a turbine vacuum pump body, an inlet pipe at one end of the pump body, a pressure transmitter on the side wall of the inlet pipe, a vacuum gauge next to the pressure transmitter, and an electric anti-surge valve on the side wall of the inlet pipe. This utility model achieves precise acquisition and control of dual parameters through the cooperation of the turbine vacuum pump body, the pressure transmitter, and the vacuum gauge. Surge conditions are judged based on the difference between "P1*1.025 and a*f+b*f²+c". When the first judgment formula is met, the electric anti-surge valve is controlled to close by 1%; when the second judgment formula is met, it is opened by 3%. This solves the misjudgment problem of existing devices and achieves full valve closure protection, avoiding valve wear caused by excessively frequent control and preventing surge caused by response lag.

Description

Technical Field

[0001] This utility model relates to the field of anti-surge control technology for turbine vacuum pumps, specifically a turbine vacuum pump with an electric anti-surge valve. Background Technology

[0002] As a core piece of equipment for fluid transport in industrial production, the anti-surge control technology of turbine vacuum pumps has undergone three development stages: mechanical throttling control, simple pressure threshold control, and composite parameter regulation. Early mechanical throttling control limited flow by manually adjusting valve opening, resulting in lag and low accuracy. After the 1990s, simple pressure threshold control relied on a single inlet pressure signal to trigger valve action, but it did not take into account the turbine's operating frequency, making it prone to misjudgment due to fluctuations in operating conditions. In recent years, composite parameter regulation technology has introduced detection parameters such as flow rate and temperature, which improves accuracy, but requires the additional installation of flow meters, differential pressure transmitters, and other instruments, increasing equipment costs and pipeline complexity. At the same time, multi-parameter coupled calculations can easily lead to control delays and are difficult to adapt to the impeller performance differences of different turbine models.

[0003] The existing device has the following defects: First, it does not use the turbine frequency as the core judgment parameter, ignoring the direct impact of frequency changes on impeller surge conditions. When the turbine is running at a non-rated frequency, the anti-surge vibration is prone to false triggering or missed triggering. Second, it uses a fixed threshold as the control basis and does not set up a parameter calibration mechanism adapted to the impeller performance of different equipment, resulting in poor versatility. Third, the control program does not include action restriction logic in the fully closed valve state, which may lead to excessive valve closure and mechanical damage. At the same time, the control cycle is not clearly defined, making it difficult to ensure the stability and timeliness of the control response. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a turbine vacuum pump with an electric anti-surge valve. It has the advantages of precise control based on dual parameters of vacuum degree and frequency, parameter calibration function adapted to different equipment, and a sound valve action protection mechanism. It solves the problems of existing devices being prone to misjudgment due to the lack of frequency parameter integration, poor versatility, and easy damage to the valve due to lack of valve protection.

[0005] To achieve the above-mentioned objectives of precise control based on dual parameters of vacuum degree and frequency, parameter calibration function adapted to different equipment, and perfect valve action protection mechanism, this utility model provides the following technical solution: a turbine vacuum pump with an electric anti-surge valve, including a turbine vacuum pump body, an air inlet pipe provided at one end of the turbine vacuum pump body, a pressure transmitter provided on the side wall of the air inlet pipe, a vacuum gauge provided next to the pressure transmitter, and an electric anti-surge valve also provided on the side wall of the air inlet pipe.

[0006] Preferably, the pressure transmitter is fixedly connected to the air inlet pipe, and a sealing gasket is provided at the connection.

[0007] Preferably, the pressure transmitter is installed at the inlet end of the air inlet pipe near the turbine vacuum pump body, and the electric anti-surge valve is installed on the air inlet pipe.

[0008] Preferably, an exhaust pipe is installed on the side wall of the turbine vacuum pump body.

[0009] Preferably, a drive motor is provided at the other end of the turbine vacuum pump body.

[0010] Preferably, a coupling is installed at one output end of the drive motor, and a speed increaser is connected to the other end of the coupling.

[0011] Preferably, a fine filter is installed on the side wall of the coupling.

[0012] Preferably, the air inlet pipe is detachably and fixedly installed to the turbine vacuum pump body via at least one segmented pipe.

[0013] Preferably, the side wall of the turbine vacuum pump body is provided with a cooler.

[0014] Preferably, the cooler is provided with heat dissipation pipes, which pass through the fine filter and are fixedly connected to the fine filter.

[0015] Compared with the prior art, this utility model provides a turbine vacuum pump with an electric anti-surge valve, which has the following beneficial effects: This device with anti-surge control program achieves precise acquisition and control of dual parameters through the cooperation of the turbine vacuum pump body, pressure transmitter and vacuum gauge. Based on the difference between "P1*1.025 and a*f+b*f²+c", it judges the surge condition. When the first judgment formula is met, it controls the electric anti-surge valve to close by 1% and opens by 3% when the second judgment formula is met. This solves the misjudgment problem of existing devices and realizes full valve closure protection. It avoids valve wear caused by excessive control and prevents surge caused by response lag. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is the circuit diagram of the turbine vacuum pump of this utility model.

[0017] In the diagram: 1. Turbine vacuum pump body; 2. Inlet pipe; 21. Electric anti-surge valve; 22. Pressure transmitter; 23. Vacuum gauge; 3. Exhaust pipe; 4. Drive motor; 5. Heat dissipation pipe; 6. Cooler; 7. Fine filter; 8. Coupling; 9. Speed ​​increaser; 10. Segmented pipeline. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] like Figure 1 As shown, a turbine vacuum pump with an electric anti-surge valve 21 includes a turbine vacuum pump body 1, an inlet pipe 2 at one end of the turbine vacuum pump body 1, a pressure transmitter 22 on the side wall of the inlet pipe 2, a vacuum gauge 23 next to the pressure transmitter 22, and an electric anti-surge valve 21 on the side wall of the inlet pipe 2. When the flow rate of the turbine vacuum pump is too low, it may enter the surge zone, causing severe airflow pulsation, increased vibration, and even serious failures such as impeller breakage and bearing damage. The pressure transmitter 22 continuously monitors the pressure of the inlet pipe 2, and the vacuum gauge 23 monitors the vacuum level. The data from both are used to determine the system operating condition. When the flow rate approaches the surge critical value, the electric anti-surge valve 21 automatically opens, increasing the flow rate by venting or recirculating gas, thus moving the operating point away from the surge zone and achieving the anti-surge effect.

[0020] Furthermore, in one embodiment of this utility model, the pressure transmitter 22 is fixedly connected to the inlet pipe of the air inlet, and a sealing gasket is provided at the connection; the two pipe end faces are pressed together, and the sealing gasket is sandwiched in the middle to form a static seal. After the gasket is compressed, it undergoes elastic or plastic deformation, blocking the leakage path of the medium; the bolt fastening method does not require welding or thread processing, and the pressure transmitter 22 or the gasket can be quickly disassembled and replaced during the maintenance of the turbine vacuum pump, reducing downtime.

[0021] like Figure 1 and Figure 2 As shown, the pressure transmitter 22 is installed at the inlet end of the air inlet pipe 2 near the inlet end of the turbine vacuum pump body 1, and the electric anti-surge valve 21 is installed on the pipeline of the air inlet pipe 2. The pressure transmitter 22 is installed close to the pump inlet and can directly detect the pressure of the medium entering the pump body, avoiding pressure loss or fluctuation interference caused by pipeline length, and providing a basis for the rapid response of the electric anti-surge valve 21. The electric anti-surge valve 21 is installed on the air inlet pipe 2 and can quickly adjust the flow rate by venting or recirculating gas to prevent surge from occurring.

[0022] like Figure 1 and Figure 2 As shown, an exhaust pipe 3 is installed on the side wall of the turbine vacuum pump body 1. The exhaust pipe 3 is installed close to the side wall of the vent pipe, so that the compressed gas in the pump can be discharged without passing through a long pipeline, which greatly reduces the airflow resistance. Under variable load conditions, the exhaust pipe 3 on the side wall can quickly adjust the exhaust volume to maintain the pressure inside the pump and avoid surge or efficiency reduction caused by poor exhaust.

[0023] like Figure 1 As shown, a drive motor 4 is provided at the other end of the turbine vacuum pump body 1; the motor and the pump body are connected by a coupling, which supports quick disassembly and replacement. The drive motor 4 in this utility model is a commercially available part.

[0024] Furthermore, in one embodiment of this utility model, a PLC control cabinet is connected to the outside of the turbine vacuum pump body 1; the anti-surge control program is input into the PLC control cabinet, and the signal of the electric anti-surge valve control point is collected, analyzed, controlled and automatically adjusted by the PLC control cabinet. The control program is preset with a first judgment formula "P1*1.025<a*f+b*f²+c-2" and a second judgment formula "P1*1.025>a*f+b*f²+c", where P1 is the absolute value of vacuum degree (unit Kpa) collected by the pressure transmitter 22, and the value of P1 is 60 when calculated. f is the turbine frequency (unit Hz, value 35-50Hz) collected by the frequency sensor, and a, b, and c are impeller performance parameters and are input by the parameter calibration module.

[0025] like Figure 1 As shown, a coupling 8 is installed at one output end of the drive motor 4, and a speed increaser 9 is connected to the other end of the coupling 8; a fine filter 7 is installed on the side wall of the coupling 8; the coupling 8 serves as the connection hub between the drive motor 4 and the speed increaser 9, directly transmitting the torque output by the drive motor 4 to the speed increaser 9, ensuring the continuity of the power chain; the coupling 8 compensates for shaft misalignment caused by installation errors, bearing wear, or thermal expansion through elastic elements or structural characteristics, reducing vibration and noise in the transmission system; the fine filter 7 is installed on the side wall of the coupling 8 to filter out tiny particles in the oil, preventing impurities from entering the speed increaser 9.

[0026] like Figure 1 As shown, the intake pipe 2 and the turbine vacuum pump body 1 are detachably fixedly installed through at least one section of segmented pipe 10; the segmented pipe 10 is connected by flanges, clamps or quick connectors, without the need for welding or complicated tools, and individual pipe sections can be quickly disassembled for cleaning, replacement or repair; expansion joints can be installed at the connection of the segmented pipe 10 to absorb the vibration generated by the vacuum pump during operation and reduce noise transmission.

[0027] like Figure 1 As shown, a cooler 6 is provided on the side wall of the turbine vacuum pump body 1. A heat dissipation pipe 5 is laid on the cooler 6. The heat dissipation pipe 5 passes through the fine filter 7 and is fixedly connected to the fine filter 7. The heat dissipation pipe 5 optimizes the heat conduction path and ensures timely heat dissipation during the operation of the turbine vacuum pump, thereby extending its service life.

[0028] Working principle: Surge is prevented by supplying external air through the anti-surge valve on the pipeline. The surge condition of the turbine vacuum pump is determined by the inlet vacuum level and the turbine frequency. The specific formula parameters are as follows: If P1*1.025<a*f+b*f²+c-2 Then the electric anti-surge valve 21 closes by 1%. If the valve is fully closed, the closing action will stop. If P1*1.025>a*f+b*f²+c Then the electric anti-surge valve 21 opens by 3%. P1: Unit of vacuum degree (-Kpa); f: Turbine frequency (Hz), range 35-50Hz; The control cycle is 3 seconds.

[0029] The calculation of P1 uses a positive value. Assuming the collected vacuum degree is -60 kPa, the value of P1 in the calculation is 60. 1.025 is a coefficient summarized by the company after multiple tests. The other parameters such as abc need to be calculated based on the impeller performance parameters according to different equipment. The first version is estimated based on the simulation, and the final relevant values ​​are verified based on actual tests.

[0030] In summary, this device with anti-surge control program, through the cooperation of the turbine vacuum pump body 1, pressure transmitter 22 and vacuum gauge 23, achieves accurate acquisition and control of dual parameters, solves the misjudgment problem of existing devices, realizes full valve closure protection, avoids mechanical damage, ensures stable control response, and ultimately achieves a precise, universal, and safe anti-surge control effect.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A turbomolecular vacuum pump with electric anti-surge valve, comprising a turbomolecular vacuum pump body (1), characterized in that: The turbine vacuum pump body (1) is provided with an air inlet pipe (2) at one end, a pressure transmitter (22) is provided on the side wall of the air inlet pipe (2), a vacuum gauge (23) is provided on the side of the pressure transmitter (22), and an electric anti-surge valve (21) is also provided on the side wall of the air inlet pipe (2).

2. A turbomolecular vacuum pump with electric anti-surge valve according to claim 1, characterized in that: The pressure transmitter (22) is fixedly connected to the inlet pipe of the air inlet pipe (2), and a sealing gasket is provided at the connection.

3. A turbomolecular vacuum pump with electric anti-surge valve according to claim 1, characterized in that: The pressure transmitter (22) is installed on the inlet end of the air inlet pipe (2) near the inlet end of the turbine vacuum pump body (1), and the electric anti-surge valve (21) is installed on the pipeline of the air inlet pipe (2).

4. A turbomolecular vacuum pump with electric anti-surge valve according to claim 1, characterized in that: An exhaust pipe (3) is installed on the side wall of the main body (1) of the turbine vacuum pump.

5. A turbomolecular vacuum pump with electric anti-surge valve according to claim 1 or 4, characterized in that: The turbine vacuum pump body (1) is equipped with a drive motor (4) at the other end.

6. A turbomolecular vacuum pump with electric anti-surge valve according to claim 5, characterized in that: A coupling (8) is installed at one output end of the drive motor (4), and a speed increaser (9) is connected to the other end of the coupling (8).

7. A turbomolecular vacuum pump with electric anti-surge valve according to claim 6, characterized in that: A fine filter (7) is installed on the side wall of the coupling (8).

8. A turbine vacuum pump with an electric anti-surge valve according to claim 1, characterized in that: The air inlet pipe (2) and the turbine vacuum pump body (1) are detachably and fixedly installed through at least one segmented pipe (10).

9. A turbine vacuum pump with an electric anti-surge valve according to claim 1, characterized in that: The side wall of the turbine vacuum pump body (1) is provided with a cooler (6).

10. A turbine vacuum pump with an electric anti-surge valve according to claim 9, characterized in that: The cooler (6) is provided with heat dissipation pipes (5), which pass through the fine filter (7) and are fixedly connected to the fine filter (7).

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