Steam turbine unit vacuum leak detection system and vacuum leak detection method

Abstract

The embodiment of the present invention provides a steam turbine unit vacuum leak detection system and a vacuum leak detection method, which belong to the technical field of steam turbine unit inspection. The system includes: a vacuum system, which is connected to the steam turbine unit and is used to extract gas entering the steam turbine unit from the leak point of the steam turbine unit, process the extracted gas into dry gas and discharge it into the atmosphere to maintain the steam turbine unit in a vacuum state; a vacuum leak detection system, which includes a display operation control corresponding to the leak point, is connected to the vacuum system and is used to analyze and perform logical operations on the gas entering the steam turbine unit from the leak point, determine the helium leakage amount and leakage level of the leak point, and display the location information of the leak point, the helium leakage amount and the leakage level when receiving the trigger operation of the display operation control corresponding to the leak point. The present invention sets a vacuum leak detection system at the back end of the vacuum system, so that the location information, helium leakage amount and leakage level of the leak point can be remotely monitored, thereby avoiding the traditional vacuum leak detection method and improving work efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of steam turbine unit inspection, in particular to a steam turbine unit vacuum leak detection system and a steam turbine unit vacuum leak detection method. Background Art

[0002] Condenser vacuum significantly impacts the operational safety, reliability, stability, and thermal economy of condensing steam turbine units. Factors affecting condenser vacuum include, but are not limited to, external air infiltration, scaling of the condenser titanium (copper) tubes, insufficient circulating water, and unit load. Excessive air infiltration is the most common cause of reduced unit vacuum.

[0003] The hazards of poor vacuum tightness of steam turbines are mainly manifested in the following three aspects: (1) When the vacuum tightness is poor, the amount of air leaking into the vacuum system increases, and the vacuum equipment is not sufficient to remove the leaked air in time, causing the exhaust temperature and exhaust pressure of the unit to rise, directly reducing the efficiency of the steam turbine unit and increasing the coal consumption for power generation. In serious cases, it threatens the safe operation of the steam turbine unit. In addition, due to the increase of air in the vacuum system, the heat transfer coefficient of the cold end heat exchanger is greatly reduced, affecting the cooling capacity; (2) Although the air leaking into the vacuum system can be removed in time, the load of the vacuum equipment needs to be increased, which increases the power consumption of the plant; (3) Due to the leakage of air, the condenser is too undercooled, which can easily cause the dissolved oxygen in the condensate to increase, increasing the probability of oxygen corrosion of the equipment.

[0004] Currently, helium mass spectrometers are the primary method for detecting vacuum leaks in steam turbine units. However, this process still relies on traditional methods: following a defined leak checklist, each pipe, valve, and weld is checked for leaks. Helium is sprayed on any potential leaking areas, and the helium mass spectrometer is waited for a response. If no response is detected, the next area is searched. This method involves a lot of repetitive work, takes a long time to detect, and has low efficiency. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a steam turbine unit vacuum leak detection system and a vacuum leak detection method to solve the problem of low working efficiency of the existing steam turbine unit vacuum leak detection method.

[0006] In order to achieve the above-mentioned object, an embodiment of the present invention provides a steam turbine unit vacuum leak detection system, comprising:

[0007] a vacuum system, connected to the steam turbine unit, for extracting gas entering the steam turbine unit from a leakage point of the steam turbine unit, treating the extracted gas into dry gas and discharging it into the atmosphere, so as to maintain the steam turbine unit in a vacuum state;

[0008] A vacuum leak detection system includes a display operation control corresponding to the leak point, is connected to the vacuum system, and is used to analyze and perform logical operations on the gas entering the steam turbine unit from the leak point, determine the helium leakage amount and leakage level of the leak point, and display the location information of the leak point, the helium leakage amount and leakage level when receiving a user trigger operation on the display operation control corresponding to the leak point.

[0009] Optionally, the vacuum system includes: a vacuum pipe, an exhaust pipe, a vacuum pump and a steam-water separator; the vacuum pump and the steam-water separator are installed on the vacuum pipe; the vacuum pump is located at the front end of the steam-water separator; the exhaust pipe is connected to the vacuum leak detection system;

[0010] The vacuum pump is used to extract air entering the steam turbine unit from the leak point in a normal state, and to extract air and helium entering the steam turbine unit from the leak point in a vacuum leak detection state;

[0011] The steam-water separator is used to separate the gas entering the steam turbine unit from the leakage point to obtain dry gas, and discharge the dry gas into the atmosphere through the exhaust pipe to maintain the steam turbine unit in a vacuum state.

[0012] Optionally, the vacuum leak detection system includes: a helium mass spectrometer leak detector and a distributed logic control system; the helium mass spectrometer leak detector is connected to the exhaust pipe; the distributed logic control system includes a display operation control corresponding to the leak point;

[0013] The helium mass spectrometer leak detector is used to analyze the air and helium entering the steam turbine unit from the leak point, determine the helium leakage amount of the leak point, and upload the helium leakage amount of the leak point to the distributed logic control system;

[0014] The distributed logic control system is used to perform logical operations on the helium leakage amount of the leak point, determine the leakage level of the leak point, and display the location information, helium leakage amount and leakage level of the leak point when receiving a trigger operation of the display operation control corresponding to the leak point by the user.

[0015] Optionally, the distributed logic control system includes: a calculation module, an identification module and a display module; the display module includes a display operation control corresponding to the leakage point;

[0016] The calculation module is used to calculate the helium leakage amount of the leak point and the preset helium content using formula (1) to obtain the corrected helium leakage amount of the leak point;

[0017] Y=AB (1);

[0018] Wherein, Y represents the corrected helium leakage of the leak point; A represents the helium leakage of the leak point; B represents the preset helium content;

[0019] The identification module is used to perform a logical operation on the corrected helium leakage amount of the leak point to determine the leakage level of the leak point, and send the corrected helium leakage amount and leakage level of the leak point to the display module;

[0020] The display module is used to display the location information of the leak point, the corrected helium leakage amount and the leakage level when receiving a trigger operation of the display operation control corresponding to the leak point by the user.

[0021] Optionally, the identification module includes: a first identification unit, a second identification unit and a third identification unit;

[0022] The first identification unit is used to identify the leak point when the corrected helium leakage is between 0 and 3.6×10 -6 mbar·l / s, the leakage level of the leak point is determined to be 0, and the corrected helium leakage amount of the leak point and the corresponding value of the leakage level are sent to the display module;

[0023] The second identification unit is used to identify the leak point when the corrected helium leakage is within 1.0×10 -5 ~9.9×10 -5 mbar·l / s, the leakage level of the leak point is determined to be 1, and the corrected helium leakage amount of the leak point and the numerical value corresponding to the leakage level are sent to the display module;

[0024] The third identification unit is used to identify the leak point when the corrected helium leakage is within 1.0×10 -4 ~9.9×10 -4 When the leakage level is within the range of mbar·l / s, the leakage level of the leakage point is determined to be 2, and the corrected helium leakage amount of the leakage point and the numerical value corresponding to the leakage level are sent to the display module.

[0025] Optionally, the distributed logic control system includes an early warning module; the display module includes a vacuum tightness numerical control;

[0026] The helium mass spectrometer leak detector is further used to analyze the air entering the steam turbine unit from the leak point at any two moments under normal conditions, and determine a first air leakage amount and a second air leakage amount of the leak point;

[0027] The early warning module is used to calculate the first air leakage amount of the leakage point, the second air leakage amount of the leakage point and the arbitrary two moments using formula (2) to obtain the tightness value of the steam turbine unit;

[0028]

[0029] Wherein: X represents the tightness value of the steam turbine unit; α represents the first air leakage of the leakage point; β represents the second air leakage of the leakage point; α h and β h represents any two moments;

[0030] The early warning module is further configured to send the tightness value of the steam turbine unit to the display module when the tightness value of the steam turbine unit is greater than a preset tightness value;

[0031] The display module is further configured to display the tightness value of the steam turbine unit in the vacuum tightness numerical control to remind the user that a gas leak occurs in the steam turbine unit.

[0032] Optionally, the distributed logic control system includes a terminal device; the display module is communicatively connected to the terminal device;

[0033] The display module is further configured to transmit the location information of the leak point, the amount of helium leakage, and the leakage level to the terminal device;

[0034] The terminal device is used to generate voice prompt information according to the location information of the leak point, the amount of helium leakage and the leakage level, so that the staff can take corresponding blocking measures for the leak point according to the voice prompt information.

[0035] Optionally, the display module includes a plurality of display operation controls; there are a plurality of leakage points on the steam turbine unit; and the plurality of display operation controls correspond one-to-one to the plurality of leakage points.

[0036] Optionally, the helium mass spectrometer leak detector is communicatively connected to the distributed logic control system via a wired transmission cable.

[0037] A second aspect of the present invention further provides a steam turbine unit vacuum leak detection method, which is performed based on the above-mentioned distributed logic control system, and the method comprises:

[0038] Obtaining a helium leakage amount at a leak point of the steam turbine unit; wherein the helium leakage amount at the leak point is obtained by analyzing the helium entering the steam turbine unit from the leak point using a helium mass spectrometer leak detector;

[0039] Using formula (1), the helium leakage amount of the leak point and the preset helium content are calculated to obtain the corrected helium leakage amount of the leak point;

[0040] Y=AB (1);

[0041] Wherein, Y represents the corrected helium leakage of the leak point; A represents the helium leakage of the leak point; B represents the preset helium content;

[0042] Performing a logical operation on the corrected helium leakage amount of the leak point to determine the leakage level of the leak point;

[0043] The location information of the leak point, the amount of helium leakage and the leakage level are displayed.

[0044] In this embodiment, a vacuum leak detection system is provided at the rear end of a vacuum system connected to the steam turbine unit, so that the amount of helium entering from a leak point on the steam turbine unit, that is, the amount of helium leakage at the leak point, can be detected. After performing a logical operation on the helium leakage at the leak point, the gas leakage level of the leak point is determined, and finally the location information of the leak point, the amount of helium leakage, and the leakage level are displayed. This enables the user to remotely monitor the helium leakage amount and leakage level of the leak point by simply spraying helium at the leak point, avoiding the need to use a helium mass spectrometer leak detector to go to the site to detect each leak point one by one, thereby improving work efficiency.

[0045] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0047] Figure 1 A schematic structural diagram of a steam turbine vacuum leak detection system according to an embodiment of the present invention;

[0048] Figure 2 A schematic diagram of the structure of a distributed logic control system provided by an embodiment of the present invention;

[0049] Figure 3 A schematic structural diagram of a distributed logic control system provided by another embodiment of the present invention;

[0050] Figure 4 A schematic diagram of a display interface of a display module provided in an embodiment of the present invention;

[0051] Figure 5 A schematic diagram of the principle of a helium mass spectrometer leak detector provided by an embodiment of the present invention.

[0052] Description of Reference Numerals

[0053] 1. Steam turbine unit vacuum leak detection system; 10. Steam turbine unit;

[0054] 11. Leakage point; 20. Vacuum system; 21. Vacuum pipeline;

[0055] 22. Vacuum pump; 23. Steam-water separator; 24. Exhaust pipe;

[0056] 30. Vacuum leak detection system; 31. Helium mass spectrometer leak detector;

[0057] 32. Distributed logic control system; 321. Operation module,

[0058] 322. Identification module; 323. Display module; 324. Early warning module;

[0059] 325; terminal device; 3221, first identification unit;

[0060] 3222, second identification unit; 3223, third identification unit;

[0061] 3231. Display operation control; 3232. Vacuum tightness numerical control. DETAILED DESCRIPTION

[0062] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0064] In the description of the embodiments of this application, the technical terms "first," "second," etc. are used only to distinguish different objects and should not be understood to indicate or imply relative importance or to implicitly indicate the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0065] In order to facilitate understanding of the concept of the present invention, before introducing the present invention, the working process of the steam turbine unit vacuum leak detection system is first described:

[0066] Assume that there is a leak point 11 at a certain point of the steam turbine unit 10 (the leak point is estimated artificially and does not mean that there must be a leak at this point). The leak point 11 corresponds to the display operation control 3231 on the vacuum leak detection system 30. Then the staff sprays helium at the leak point 11, and then the helium and air entering from the leak point 11 are extracted through the vacuum pump 22 of the vacuum system 20. Then, the steam is separated through the steam-water separator 23 of the vacuum system 20, and then discharged to the atmosphere through the exhaust pipe 24. The exhaust pipe 24 is connected to the vacuum leak detection system 30 by adding a damping hose. Therefore, at this time, the helium mass spectrometer leak detector 31 of the vacuum leak detection system 30 will detect the helium and The air is analyzed to obtain the helium leakage amount of the leakage point 11, and then the helium leakage amount of the leakage point 11 is uploaded to the distributed logic control system 32. The distributed logic control system 32 performs logical operations on the helium leakage amount of the leakage point 11 to determine the leakage level of the leakage point 11, and when the user clicks the display operation control 3231 corresponding to the leakage point 11, the position information, helium leakage amount and leakage level of the leakage point 11 are displayed, thereby avoiding the use of the helium mass spectrometer leak detector 31 to go to the site to detect each leakage point 11 one by one. The user can directly monitor the helium leakage amount and leakage level of the leakage point 11 remotely in the distributed logic control system 32, thereby improving work efficiency.

[0067] Reference Figure 1 and Figure 4 An embodiment of the present invention provides a steam turbine unit vacuum leak detection system 1, which includes: a vacuum system 20, which is connected to the steam turbine unit 10 and is used to extract gas entering the steam turbine unit 10 from a leakage point 11 of the steam turbine unit 10, and process the extracted gas into dry gas and discharge it into the atmosphere to maintain the steam turbine unit 10 in a vacuum state; a vacuum leak detection system 30, which includes a display operation control 3231 corresponding to the leakage point 11, is connected to the vacuum system 20 and is used to analyze and perform logical operations on the gas entering the steam turbine unit 10 from the leakage point 11, determine the helium leakage amount and leakage level of the leakage point 11, and display the location information, helium leakage amount and leakage level of the leakage point 11 when receiving a trigger operation from the user on the display operation control 3231 corresponding to the leakage point 11.

[0068] It should be noted that the leakage point 11 refers to a point on the steam turbine unit 10 where leakage is estimated to occur, but does not mean that leakage will definitely occur at this point.

[0069] There are multiple leakage points 11 on the steam turbine unit 10. The specific locations of the leakage points 11 include but are not limited to: vacuum destruction door, low-pressure cylinder front shaft seal, low-pressure cylinder rear shaft seal, condensate pump seal, condenser level gauge, condensate drain valve, etc., and these leakage points 11 correspond one-to-one to the display operation controls 3231 in the vacuum leak detection system 30, that is, there are as many corresponding display operation controls 3231 as there are leakage points 11.

[0070] It should be noted that since the vacuum leak detection system 30 can only detect the amount of helium, it cannot identify the specific leak point 11 from which the helium entered. Therefore, in actual use, the amount of helium injected from only one leak point 11 can be detected simultaneously, and the amount of helium injected from multiple leak points 11 cannot be detected simultaneously. In addition, when leak detection is performed on the steam turbine unit 10, it is necessary to manually confirm the leak point 11 and then inject nitrogen at the leak point 11. In this way, the amount of helium detected by the vacuum leak detection system 30 can determine the leak point 11 from which the helium entered.

[0071] It is understood that the gas entering the steam turbine unit 10 from the leak point 11 can be air or air and helium, and the helium is artificially injected. When helium is not artificially injected at the leak point 11, the gas entering from the leak point 11 is air; when helium is artificially injected at the leak point 11, the gas entering from the leak point 11 is air and helium.

[0072] The vacuum leak detection system 30 is connected to the vacuum system 20. The helium gas entering from the leak point 11 is extracted from the vacuum system 20 for detection to determine the amount of helium leakage. Then, a logical operation is performed on the helium leakage to determine the leakage level. Finally, when the user triggers the display operation control 3231 corresponding to the leak point 11, the location information of the leak point 11, the helium leakage amount and the leakage level are displayed.

[0073] The location information of the leak point 11, the amount of helium leakage and the leakage level are as follows: Figure 4 As shown in the figure, jet point: the location information of the leak point; leakage amount: the amount of helium leakage at the leak point; leakage condition: the leakage level of the leak point.

[0074] For example: Jet point: Vacuum pump pneumatic inlet door and surrounding flange; Leakage: 5.0x10 -5 mbar·l / s; Leakage Level: Level 1. This indicates vacuum leak detection of the steam turbine unit by injecting helium at the vacuum pump's pneumatic inlet door and surrounding flanges. The location, helium leakage, and leakage conditions of other leaks are similar and are not detailed here.

[0075] The steam turbine vacuum leak detection system 1 provided in this embodiment of the present invention can inject helium at any leak point 11, thereby enabling remote monitoring of the leak point 11's location, helium leakage, and leakage level at the vacuum leak detection system 30. However, it should be noted that the location information, helium leakage, and leakage level of the leak point 11 are displayed only after clicking the display operation control 3231 corresponding to the leak point 11 in the vacuum leak detection system 30.

[0076] In this embodiment, a vacuum leak detection system is provided at the rear end of the vacuum system 20 connected to the steam turbine unit 10, so that the amount of helium entering from the leakage point 11 on the steam turbine unit 10, that is, the helium leakage amount of the leakage point 11, can be detected. After performing a logical operation on the helium leakage amount of the leakage point 11, the leakage level of the leakage point 11 is determined, and finally the position information, helium leakage amount and leakage level of the leakage point 11 are remotely displayed. The user only needs to spray helium at the leakage point 11, and then remotely monitor the helium leakage amount and leakage level of the leakage point 11 on the distributed logic control system 32, avoiding the need to use the helium mass spectrometer leak detector 31 to go to the site to detect each leakage point 11 one by one, thereby improving work efficiency.

[0077] Optionally, refer to Figure 1 The vacuum system 20 includes: a vacuum pipe 21, an exhaust pipe 24, a vacuum pump 22 and a steam-water separator 23; the vacuum pump 22 and the steam-water separator 23 are installed on the vacuum pipe 21; the vacuum pump 22 is located at the front end of the steam-water separator 23; the exhaust pipe 24 is connected to the vacuum leak detection system 30; the vacuum pump 22 is used to extract air entering the steam turbine unit 10 from the leakage point 11 under normal conditions, and to extract air and helium entering the steam turbine unit 10 from the leakage point 11 under vacuum leak detection conditions; the steam-water separator 23 is used to separate the gas entering the steam turbine unit 10 from the leakage point 11 into dry gas, and discharge the dry gas to the atmosphere through the exhaust pipe 24 to maintain the steam turbine unit 10 in a vacuum state.

[0078] Specifically, when the steam turbine unit 10 is not subjected to vacuum leak detection, that is, helium is not injected at the leak point 11, the vacuum pump 22 extracts air from the leak point 11 into the steam turbine unit 10; when the steam turbine unit 10 is subjected to vacuum leak detection, that is, helium is injected at the leak point 11, the vacuum pump 22 extracts air and helium from the leak point 11 into the steam turbine unit 10.

[0079] The function of the steam-water separator 23 is to prevent the non-condensable steam-water mixture in the vacuum system 20 from entering the helium mass spectrometer leak detector 31 and causing blockage.

[0080] In this embodiment, a steam-water separator 23 is provided at the rear end of the vacuum pump 22 so that the non-condensable steam-water mixture in the gas entering from the leak point 11 will not enter the helium mass spectrometer leak detector 31 and cause blockage, so that the helium mass spectrometer leak detector 31 can accurately analyze the helium gas entering from the leak point 11.

[0081] Optionally, refer to Figure 1 and Figure 5The vacuum leak detection system 30 includes: a helium mass spectrometer leak detector 31 and a distributed logic control system 32; the helium mass spectrometer leak detector 31 is connected to the exhaust pipe 24; the distributed logic control system 32 includes a display operation control 3231 corresponding to the leak point 11; the helium mass spectrometer leak detector 31 is used to analyze the air and helium entering the steam turbine unit 10 from the leak point 11, determine the helium leakage amount of the leak point 11, and upload the helium leakage amount of the leak point 11 to the distributed logic control system 32; the distributed logic control system 32 is used to perform logical operations on the helium leakage amount of the leak point 11, determine the leakage level of the leak point 11, and display the location information, helium leakage amount and leakage level of the leak point 11 when receiving the user's trigger operation for the display operation control 3231 corresponding to the leak point 11.

[0082] Specifically, the helium mass spectrometer leak detector 31 is connected to the exhaust pipe 24 via a damping hose to achieve communication with the vacuum system 20 .

[0083] Reference Figure 5 Since the molecular mass of helium is different from that of other gases, the deflection magnetic force generated by the magnetic field is also different. The helium mass spectrometer leak detector is designed with a slit on the instrument, which just allows helium molecules to pass through while other molecules cannot pass through. The helium molecules after passing through the slit hit the collection plate and are counted by the target plate. The number of helium molecules that pass through is immediately detected, and the amount of helium leakage at the leak point is finally determined.

[0084] In this embodiment, a vacuum leak detection system 30 is formed by combining a helium mass spectrometer leak detector 31 with a distributed logic control system 32, so that the location information, helium leakage amount and leakage level of the leak point 11 can be remotely monitored, thereby ensuring the safe operation of the turbine unit 10.

[0085] Optionally, refer to Figure 2 The distributed logic control system 32 includes: an operation module 321, an identification module 322 and a display module 323; the display module 323 includes a display operation control 3231 corresponding to the leakage point 11; the operation module 321 is used to calculate the helium leakage amount and the preset helium content of the leakage point 11 using formula (1) to obtain the corrected helium leakage amount of the leakage point 11; Y=AB(1); wherein Y represents the corrected helium leakage amount of the leakage point 11; A represents the helium leakage amount of the leakage point 11; B represents the preset helium content; the identification module 322 is used to perform logical operations on the corrected helium leakage amount of the leakage point 11, determine the leakage level of the leakage point 11, and send the corrected helium leakage amount and leakage level of the leakage point 11 to the display module 323; the display module 323 is used to display the position information, corrected helium leakage amount and leakage level of the leakage point 11 when receiving the user's trigger operation for the display operation control 3231 corresponding to the leakage point 11.

[0086] It should be noted that since the air also contains a small amount of helium, the amount of helium analyzed by the helium mass spectrometer leak detector 31 not only includes the helium entering the turbine unit 10 from the leak point 11, but also includes a small amount of helium in the air, so it is necessary to remove the error, and the helium content in the air is the preset helium content.

[0087] In this embodiment, the calculation module 321 uses the formula Y=AB(1) to correct the helium leakage amount of the leak point 11 analyzed by the helium mass spectrometer leak detector 31, and then the corrected helium leakage amount is identified by the identification module 322 to determine the leakage level. Finally, when the user triggers the display operation control 3231 corresponding to the leak point 11, the position information, helium leakage amount and leakage level of the leak point 11 are displayed, so that the helium leakage amount and leakage level of the leak point can be accurately monitored.

[0088] Optionally, refer to Figure 2 and Figure 4 The recognition module 322 includes: a first recognition unit 3221, a second recognition unit 3222 and a third recognition unit 3223; the first recognition unit 3221 is used to identify the leak point 11 when the corrected helium leakage is between 0 and 3.6×10 -6 mbar·l / s, the leakage level of the leak point 11 is determined to be 0, and the corrected helium leakage amount and the corresponding value of the leakage level of the leak point 11 are sent to the display module 323; the second identification unit 3222 is used to determine the leakage level of the leak point 11 when the corrected helium leakage amount is within 1.0×10 -5 ~9.9×10 -5 mbar·l / s, the leakage level of the leak point 11 is determined to be 1, and the corrected helium leakage amount of the leak point 11 and the corresponding value of the leakage level are sent to the display module 323; the third identification unit 3223 is used to determine the leakage level of the leak point 11 when the corrected helium leakage amount is within 1.0×10 -4 ~9.9×10 -4 When the leakage level of the leak point 11 is within the range of mbar·l / s, the leakage level of the leak point 11 is determined to be 2, and the corrected helium leakage amount of the leak point 11 and the numerical value corresponding to the leakage level are sent to the display module 323.

[0089] Specifically, the reading of the helium mass spectrometer leak detector 31 is uploaded to the distributed logic control system 32. When the reading is between 0 and 3.6×10 -6 mbar·l / s, which is the baseline value for no leakage, and the alarm value is level 0; when the value is within 1.0×10 -5 ~9.9×10 -5 mbar·l / s range is the first level alarm value; when its value is within 1.0×10 -4 ~9.9×10- 4 mbar·l / s range is the second level alarm value.

[0090] In one embodiment, the display operation control 3231 can set a corresponding alarm mechanism according to the leakage level identified by the identification module 322, that is, when the leakage level is level 0, the color of the display operation control 3231 corresponding to the leakage point 11 can be displayed as the original color; when the leakage level is level 1, the color of the display operation control 3231 corresponding to the leakage point 11 can be displayed as yellow; when the leakage level is level 2, the color of the display operation control 3231 corresponding to the leakage point 11 can be displayed as red.

[0091] In this embodiment, the helium leakage amount of the leak point 11 analyzed by the helium mass spectrometer leak detector 31 is identified by the first identification unit 3221, the second identification unit 3222 and the third identification unit 3223, so that the user can intuitively see the helium leakage amount and leakage situation of the leak point 11.

[0092] Optionally, refer to Figure 2 The distributed logic control system includes an early warning module 324; the display module 323 includes a vacuum tightness numerical control 3232; the helium mass spectrometer leak detector 31 is also used to analyze the air entering the steam turbine unit 10 from the leakage point 11 at any two moments under normal conditions, and determine the first air leakage amount and the second air leakage amount of the leakage point 11; the early warning module 324 is used to calculate the first air leakage amount and the second air leakage amount of the leakage point 11 at any two moments using formula (2) to obtain the tightness value of the steam turbine unit 10; Wherein: X represents the tightness value of the steam turbine unit 10; α represents the first air leakage of the leakage point 11; β represents the second air leakage of the leakage point 11; α h and β h Represents any two moments; the early warning module 324 is also used to send the tightness value of the steam turbine unit 10 to the display module 323 when the tightness value of the steam turbine unit 10 is greater than the preset tightness value; the display module 323 is also used to display the tightness value of the steam turbine unit 10 in the vacuum tightness numerical control 3232 to remind the user that a gas leak has occurred in the steam turbine unit 10.

[0093] In one embodiment, the preset tightness value may be 0.3 kPa / min. The specific value may refer to national unified standards or be user-defined, and this embodiment does not impose any specific limitation on this.

[0094] The early warning module 324 performs vacuum tightness calculations and can automatically calculate the vacuum drop values at any two moments under normal conditions. For example, the vacuum drop value (initial value a) is automatically recorded at 14:22, and the vacuum drop value (end value b) is recorded again at 14:28. The ratio of the difference between the initial value a and the end value b to the time is the tightness value of the steam turbine unit, which can be expressed as: (ab) kPa / 5min. If (ab) kPa / 5min is greater than 0.3 kPa / min, (ab) kPa / 5min will be displayed in the vacuum tightness numerical control 3232.

[0095] It should be noted that at this time, no helium is ejected from the leak point 11, so only air enters the steam turbine unit 10 from the leak point 11, and the amount of helium analyzed by the helium mass spectrometer leak detector 31 is the helium content in the air, that is, the amount of air leakage. The early warning module 324 then calculates and determines the analyzed amount of air leakage.

[0096] In this embodiment, the vacuum tightness calculation of the steam turbine unit 10 is performed through the early warning module 324 to determine whether the vacuum state of the steam turbine unit 10 is within the index (preset tightness value). If it is greater than the index (preset tightness value), the detected helium leakage amount is displayed in the vacuum tightness numerical control 3232 of the display module 323 to remind the user that the current steam turbine unit is in a poor vacuum tightness state and the steam turbine unit 10 needs to be vacuum leak checked in time.

[0097] Optionally, refer to Figure 3 The distributed logic control system 32 includes a terminal device 325; a display module 323 is communicatively connected to the terminal device 325; the display module 323 is also used to send the location information, helium leakage amount and leakage level of the leakage point 11 to the terminal device 325; the terminal device 325 is used to generate voice prompt information according to the location information, helium leakage amount and leakage level of the leakage point 11, so that the staff can take corresponding blocking measures for the leakage point 11 according to the voice prompt information.

[0098] In this embodiment, the display module 323 sends the location information, helium leakage amount and leakage level of the leakage point 11 to the terminal device 325, and then the terminal device 325 generates a voice prompt information based on the location information, helium leakage amount and leakage level of the leakage point 11. After the staff hears the location information, helium leakage amount and leakage level of the leakage point 11 broadcast by the terminal device 325, they can immediately go to the leakage point 11 and adopt corresponding sealing measures, thereby improving the vacuum rate of the turbine unit 10, avoiding the poor economy and danger of the turbine unit 10 due to unqualified tightness, and reducing the probability of the turbine unit 10 causing an emergency shutdown due to vacuum leakage.

[0099] Optionally, refer to Figure 4The display module 323 includes a plurality of display operation controls 3231 ; there are a plurality of leakage points 11 on the steam turbine unit 10 ; and the plurality of display operation controls 3231 correspond one to one with the plurality of leakage points 11 .

[0100] In this embodiment, by designing multiple display operation controls 3231 on the display module 323, the multiple display operation controls 3231 correspond one-to-one to the multiple leakage points 11 of the steam turbine unit 10, so that distributed monitoring of the multiple leakage points 11 of the steam turbine unit 10 can be performed, thereby effectively improving the vacuum rate of the steam turbine unit 10.

[0101] Optionally, the helium mass spectrometer leak detector 31 is communicatively connected to the distributed logic control system 32 via a wired transmission cable.

[0102] Due to on-site environmental factors, if the helium mass spectrometer leak detector 31 and the distributed logic control system 32 are set to wireless transmission, data transmission may be unable to proceed, resulting in errors in the data received by the distributed logic control system 32, and thus unable to accurately remotely monitor the leakage point 11 of the turbine unit 10. Therefore, by setting up a wired transmission cable for transmission, it can be ensured that the helium mass spectrometer leak detector 31 can stably transmit data to the distributed logic control system 32.

[0103] In this embodiment, by setting the communication mode between the helium mass spectrometer leak detector 31 and the distributed logic control system 32 to wired cable transmission, the helium mass spectrometer leak detector 31 can stably transmit data to the distributed logic control system 32, thereby accurately remotely monitoring the leakage point 11 of the turbine unit 10.

[0104] Based on the same inventive concept, an embodiment of the present invention further provides a method for vacuum leak detection of a steam turbine unit, which is executed based on the aforementioned distributed logic control system. The method includes the following steps:

[0105] S1: Obtaining the helium leakage amount of the leak point of the steam turbine unit; wherein the helium leakage amount of the leak point is obtained by analyzing the helium entering the steam turbine unit from the leak point using a helium mass spectrometer leak detector;

[0106] The execution body of the steam turbine unit vacuum leak detection method provided by the embodiment of the present invention is a distributed logic control system.

[0107] The helium mass spectrometer leak detector analyzes the helium entering the steam turbine unit from the leak point to obtain the helium leakage amount of the leak point. For details, please refer to Figure 5Since the molecular mass of helium is different from that of other gases, the deflection magnetic force generated by the magnetic field is also different. The helium mass spectrometer leak detector is designed with a slit on the instrument, which just allows helium molecules to pass through while other molecules cannot pass through. The helium molecules after passing through the slit hit the collection plate and are counted by the target plate. The number of helium molecules that pass through is immediately detected, and the amount of helium leakage at the leak point is finally determined.

[0108] S2: Calculate the helium leakage amount of the leak point and the preset helium content using formula (1) to obtain the corrected helium leakage amount of the leak point;

[0109] Y=AB (1);

[0110] Wherein, Y represents the corrected helium leakage of the leak point; A represents the helium leakage of the leak point; B represents the preset helium content;

[0111] It should be noted that since the air also contains a small amount of helium, the amount of helium detected by the helium mass spectrometer leak detector 31 not only includes the helium entering the turbine unit 10 from the leak point 11, but also includes a small amount of helium in the air, so it is necessary to eliminate the detection error, that is, the preset helium content refers to the helium content in the air.

[0112] S3: Performing logical operations on the corrected helium leakage amount of the leak point to determine the leakage level of the leak point;

[0113] When its value is between 0 and 3.6×10 -6 mbar·l / s, which is the baseline value for no leakage, and the alarm value is level 0; when the value is within 1.0×10 -5 ~9.9×10 -5 mbar·l / s range is the first level alarm value; when its value is within 1.0×10 -4 ~9.9×10 -4 mbar·l / s range is the second level alarm value.

[0114] S4: Display the location information of the leak point, the amount of helium leakage and the leakage level.

[0115] The location of the leak, the amount of helium leaked and the level of the leak are as follows: Figure 4 As shown in the figure, jet point: the location information of the leak point; leakage amount: the amount of helium leakage at the leak point; leakage condition: the leakage level of the leak point.

[0116] For example: Jet point: Vacuum pump pneumatic inlet door and surrounding flange; Leakage: 5.0x10 -5mbar·l / s; Leakage Level: Level 1. This indicates vacuum leak detection of the steam turbine unit by injecting helium at the vacuum pump's pneumatic inlet door and surrounding flanges. The location, helium leakage volume, and leakage conditions of other leaks are similar and are not detailed here.

[0117] In this embodiment, the helium leakage amount of the leak point is corrected to calculate the accurate helium leakage amount of the leak point, and then a logical operation is performed on the helium leakage amount of the leak point to determine the leakage level of the leak point. Finally, the location information of the leak point, the helium leakage amount and the leakage level are displayed, so that the user can remotely monitor the helium leakage amount and leakage level of the leak point of the turbine unit, avoiding the need to use a helium mass spectrometer leak detector to go to the site to detect each leak point one by one, thereby improving work efficiency.

[0118] Optionally, the above step S4 may further include: step S5.

[0119] S5: The location information of the leak point, the amount of helium leakage, and the leakage level are sent to the terminal device, so that the terminal device generates voice prompt information according to the location information of the leak point, the amount of helium leakage, and the leakage level.

[0120] In this embodiment, voice instruction information related to the location information of the leak point, the amount of helium leakage and the leakage level is generated by the terminal device, so that the staff can go to the leak point and adopt corresponding sealing measures according to the voice prompt information, thereby improving the vacuum rate of the turbine unit, avoiding the poor economy and danger of the turbine unit due to unqualified tightness, and reducing the probability of the turbine unit being shut down due to vacuum leakage.

[0121] The term "essentially consisting of..." to describe a combination should include the identified elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel features of the combination. The use of the terms "comprising" or "including" to describe the combination of elements, ingredients, parts or steps herein also contemplates embodiments that are essentially composed of these elements, ingredients, parts or steps. By using the term "may", it is intended to illustrate that any of the described attributes that "may" include are optional. Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "an" used to describe an element, ingredient, part or step is not intended to exclude other elements, ingredients, parts or steps.

[0122] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A steam turbine vacuum leak detection system, characterized in that: include: a vacuum system, connected to the steam turbine unit, for extracting gas entering the steam turbine unit from a leakage point of the steam turbine unit, treating the extracted gas into dry gas and discharging it into the atmosphere, so as to maintain the steam turbine unit in a vacuum state; a vacuum leak detection system, comprising a display operation control corresponding to the leak point, connected to the vacuum system, and configured to analyze and perform logical operations on the gas entering the steam turbine unit from the leak point, determine the helium leakage amount and leakage level of the leak point, and display the location information of the leak point, the helium leakage amount, and the leakage level upon receiving a user trigger operation on the display operation control corresponding to the leak point; The vacuum system includes: a vacuum pipe, an exhaust pipe, a vacuum pump and a steam-water separator; the vacuum pump and the steam-water separator are installed on the vacuum pipe; the vacuum pump is located at the front end of the steam-water separator; the exhaust pipe is connected to the vacuum leak detection system; The vacuum pump is used to extract air entering the steam turbine unit from the leak point in a normal state, and to extract air and helium entering the steam turbine unit from the leak point in a vacuum leak detection state; The steam-water separator is used to separate the gas entering the steam turbine unit from the leakage point to obtain dry gas, and discharge the dry gas into the atmosphere through the exhaust pipe to maintain the steam turbine unit in a vacuum state; The vacuum leak detection system includes: a helium mass spectrometer leak detector and a distributed logic control system; the helium mass spectrometer leak detector is connected to the exhaust pipe; the distributed logic control system includes a display operation control corresponding to the leak point; The helium mass spectrometer leak detector is used to analyze the air and helium entering the steam turbine unit from the leak point, determine the helium leakage amount of the leak point, and upload the helium leakage amount of the leak point to the distributed logic control system; The distributed logic control system is used to perform logical operations on the helium leakage amount of the leak point to determine the leakage level of the leak point, and display the location information, helium leakage amount and leakage level of the leak point when receiving a trigger operation of the display operation control corresponding to the leak point by the user; The distributed logic control system includes: a calculation module, an identification module and a display module; the display module includes a display operation control corresponding to the leakage point; The calculation module is used to calculate the helium leakage amount of the leak point and the preset helium content using formula (1) to obtain the corrected helium leakage amount of the leak point; （1）； in, Indicates the corrected helium leakage at the leak point; Indicates the amount of helium leakage at the leak point; Indicates the preset helium content; The identification module is used to perform a logical operation on the corrected helium leakage amount of the leak point to determine the leakage level of the leak point, and send the corrected helium leakage amount and leakage level of the leak point to the display module; The display module is configured to display the location information of the leak point, the corrected helium leakage amount, and the leakage level upon receiving a trigger operation of the display operation control corresponding to the leak point by the user; The distributed logic control system includes an early warning module; the display module includes a vacuum tightness numerical control; The helium mass spectrometer leak detector is further used to analyze the air entering the steam turbine unit from the leak point at any two moments under normal conditions, and determine a first air leakage amount and a second air leakage amount of the leak point; The early warning module is used to calculate the first air leakage amount of the leakage point, the second air leakage amount of the leakage point and the two arbitrary moments using formula (2) to obtain the tightness value of the steam turbine unit; （2）； in; Indicates the tightness value of the steam turbine unit; Indicates the first air leakage rate of the leak point; Indicates the second air leakage rate of the leak point; and represents any two moments; The early warning module is further configured to send the tightness value of the steam turbine unit to the display module when the tightness value of the steam turbine unit is greater than a preset tightness value; The display module is further configured to display the tightness value of the steam turbine unit in the vacuum tightness numerical control to remind the user that a gas leak occurs in the steam turbine unit.

2. The steam turbine unit vacuum leak detection system according to claim 1, characterized in that: The recognition module includes: a first recognition unit, a second recognition unit and a third recognition unit; The first identification unit is used to identify the leak point when the corrected helium leakage is between 0 and 3.6×10 -6 mbar·l / s, the leakage level of the leak point is determined to be 0, and the corrected helium leakage amount of the leak point and the corresponding value of the leakage level are sent to the display module; The second identification unit is used to identify the leak point when the corrected helium leakage is within 1.0×10 -5 ~9.9×10 - 5 mbar·l / s, the leakage level of the leak point is determined to be 1, and the corrected helium leakage amount of the leak point and the numerical value corresponding to the leakage level are sent to the display module; The third identification unit is used to identify the leak point when the corrected helium leakage is within 1.0×10 -4 ~9.9×10 - 4 When the leakage level is within the range of mbar·l / s, the leakage level of the leakage point is determined to be 2, and the corrected helium leakage amount of the leakage point and the numerical value corresponding to the leakage level are sent to the display module.

3. The steam turbine vacuum leak detection system according to claim 1, characterized in that: The distributed logic control system includes a terminal device; the display module is communicatively connected to the terminal device; The display module is further configured to transmit the location information of the leak point, the amount of helium leakage, and the leakage level to the terminal device; The terminal device is used to generate voice prompt information according to the location information of the leak point, the amount of helium leakage and the leakage level, so that the staff can take corresponding blocking measures for the leak point according to the voice prompt information.

4. The steam turbine vacuum leak detection system according to claim 1, characterized in that: The display module includes a plurality of display operation controls; there are a plurality of leakage points on the steam turbine unit; and the plurality of display operation controls correspond one to one to the plurality of leakage points.

5. The steam turbine vacuum leak detection system according to claim 1, characterized in that: The helium mass spectrometer leak detector is communicatively connected to the distributed logic control system via a wired transmission cable.

6. A method for vacuum leak detection of a steam turbine unit, executed based on the distributed logic control system according to claim 1, characterized in that: The method comprises: Obtaining a helium leakage amount at a leak point of the steam turbine unit; wherein the helium leakage amount at the leak point is obtained by analyzing the helium entering the steam turbine unit from the leak point using a helium mass spectrometer leak detector; Using formula (1), the helium leakage amount of the leak point and the preset helium content are calculated to obtain the corrected helium leakage amount of the leak point; （1）； in, Indicates the corrected helium leakage at the leak point; Indicates the amount of helium leakage at the leak point; Indicates the preset helium content; Performing a logical operation on the corrected helium leakage amount of the leak point to determine the leakage level of the leak point; The location information of the leak point, the amount of helium leakage and the leakage level are displayed.

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