Lubricating oil tank negative pressure pumping device and turboset with same

Abstract

The utility model provides a lubricating oil tank negative pressure pumping device and a turboset with the lubricating oil tank negative pressure pumping device, the lubricating oil tank negative pressure pumping device comprises a pumping mechanism, a noise reduction mechanism and an oil-gas separation mechanism, and at least one part of the pumping mechanism is used for being communicated with a lubricating oil tank to pump oil gas; the noise reduction mechanism is communicated with the extraction mechanism; the oil-gas separation mechanism communicates with the end, away from the extraction mechanism, of the noise reduction mechanism. The lubricating oil tank negative pressure pumping device solves the problem that in the prior art, a lubricating oil tank negative pressure pumping device seriously pollutes the environment.

Description

Technical Field

[0001] The utility model relates to the technical field of air separation devices, in particular to a lubricating oil tank negative pressure extraction device and a steam turbine unit having the same. Background Art

[0002] With the clustered development of large-scale air separation units in my country, it is crucial that steam turbines, as their core drive equipment, maintain stable operation. Steam turbines generate a large amount of heat during high-speed operation, which not only consumes energy but can also shorten the life of the equipment. To alleviate this problem, lubricating oil is usually added to the steam turbine to form a lubricating film to reduce direct contact between components, thereby effectively reducing friction and wear and ensuring long-term operation of the equipment. However, while the lubricating oil removes heat, it also produces a large amount of oil and gas, causing the lubricating oil system to be in a positive pressure state, which in turn affects the return flow of the lubricating oil system, causing abnormal increases in bearing temperatures, and posing a major threat to production safety.

[0003] To maintain the stability of the lubricating oil system and ensure the continuity and reliability of steam turbine operation, it is necessary to maintain an appropriate negative pressure within the lubricating oil tank. This negative pressure facilitates the return of lubricating oil, accelerates the volatilization of water in the lubricating oil, prevents emulsification, and effectively ensures the stable operation of the steam turbine. To achieve this negative pressure in the oil tank, an oil mist blower is often used to extract oil and vapor from the tank. An oil mist blower primarily consists of a housing, motor, impeller, and air guide vanes, discharging oil and vapor from the oil tank through a fan. When the oil mist blower is operating, oil and vapor enter the oil mist blower housing through a pipe. Passing through the air guide vanes and impeller, the high-speed rotation of the impeller creates a strong negative pressure, sucking the oil and vapor out and discharging it through an air duct to the outside. This creates negative pressure, promotes the return of lubricating oil, and mitigates the risk of explosion caused by oil and vapor accumulation. However, direct discharge of oil and vapor can cause significant air pollution, and the noise generated during operation is detrimental to the working environment and operator health.

[0004] That is to say, the prior art lubricating oil tank negative pressure extraction device has the problem of serious environmental pollution. Utility Model Content

[0005] The main purpose of the utility model is to provide a lubricating oil tank negative pressure pumping device and a steam turbine unit having the same, so as to solve the problem of serious environmental pollution caused by the lubricating oil tank negative pressure pumping device in the prior art.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the utility model, a lubricating oil tank negative pressure extraction device is provided, including: an extraction mechanism, at least a part of the extraction mechanism is used to connect to the lubricating oil tank to extract oil and gas; a noise reduction mechanism, the noise reduction mechanism is connected to the extraction mechanism; and an oil-gas separation mechanism, the oil-gas separation mechanism is connected to an end of the noise reduction mechanism away from the extraction mechanism.

[0007] Furthermore, the extraction mechanism includes an extraction component, which can be connected to the lubricating oil tank and the noise reduction mechanism to extract oil and gas.

[0008] Furthermore, the extraction component includes a venturi tube, and the lubricating oil tank and the noise reduction mechanism are respectively located at two ends of the venturi tube.

[0009] Furthermore, the extraction mechanism also includes a power assembly, which is connected to one end of the venturi tube close to the lubricating oil tank.

[0010] Furthermore, the power assembly includes an instrument air source, which is connected to one end of the venturi tube close to the lubricating oil tank to input instrument air into the venturi tube.

[0011] Furthermore, the power assembly also includes a compressed air source, which is connected to one end of the venturi tube close to the lubricating oil tank to input compressed air into the venturi tube.

[0012] Furthermore, the power assembly further includes a first check valve and a second check valve, the first check valve is connected between the instrument air source and the venturi tube, and the second check valve is connected between the compressed air source and the venturi tube.

[0013] Furthermore, the oil-gas separation mechanism includes at least one group of oil-gas separation components, one end of which is connected to the end of the noise reduction mechanism away from the extraction mechanism, and the oil-gas separation component can separate oil and gas into condensable objects and non-condensable gases.

[0014] Furthermore, the oil-gas separation mechanism includes at least two groups of oil-gas separation components, and the oil-gas separation mechanism also includes at least one group of three-way switching valves, which are connected between the noise reduction mechanism and the two groups of oil-gas separation components.

[0015] According to another aspect of the present invention, a steam turbine unit is provided, comprising the above-mentioned lubricating oil tank negative pressure extraction device.

[0016] Applying the technical solution of the present invention, the negative pressure extraction device for the lubricating oil tank includes an extraction mechanism, a noise reduction mechanism and an oil-gas separation mechanism. At least a part of the extraction mechanism is used to connect to the lubricating oil tank to extract oil and gas; the noise reduction mechanism is connected to the extraction mechanism; and the oil-gas separation mechanism is connected to one end of the noise reduction mechanism away from the extraction mechanism.

[0017] In order to improve the safety of the lubricating oil tank negative pressure extraction device, the core of the lubricating oil tank negative pressure extraction device of the present application is composed of three modules: an extraction mechanism, a noise reduction mechanism, and an oil-gas separation mechanism, which are connected in sequence. A part of the extraction mechanism is directly connected to the lubricating oil tank to extract the oil and gas. The noise generated during the oil and gas extraction process is effectively absorbed by the noise reduction mechanism, which greatly reduces noise pollution. The oil-gas separation mechanism is located at the end of the noise reduction mechanism away from the extraction mechanism, and separates the oil and gas extracted from the lubricating oil tank, recovers the lubricating oil, and discharges non-condensable gas at the same time. While saving resources, the discharged gas can also be selectively controlled to reduce air pollution. The extraction mechanism, noise reduction mechanism, and oil-gas separation mechanism of the lubricating oil tank negative pressure extraction device of the present application work together, significantly improving the safety of the lubricating oil tank negative pressure extraction device and the comfort of the working environment, effectively controlling noise pollution and air pollution, and providing a safer, more environmentally friendly and economical solution for maintaining negative pressure inside the lubricating oil tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings constituting part of this application are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0019] Figure 1 The figure shows a structural diagram of a first embodiment of a negative pressure extraction device for a lubricating oil tank according to the present invention.

[0020] The above drawings include the following reference numerals:

[0021] 10. Lubricating oil tank; 11. Oil and gas inlet valve; 20. Extraction mechanism; 21. Air inlet valve; 22. Venturi tube; 23. Instrument air source; 24. Instrument air regulating valve; 25. First check valve; 26. Compressed air source; 27. Self-operated regulating valve; 28. Second check valve; 30. Noise reduction mechanism; 31. Drain valve; 40. Oil and gas separation mechanism; 41. Oil and gas separation assembly; 42. Three-way switching valve; 43. Lubricating oil discharge valve; 44. Release port. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0024] In the present invention, unless otherwise specified, directional words such as "up, down, top, bottom" are usually used with reference to the directions shown in the drawings, or with reference to the components themselves in the vertical, perpendicular or gravity direction; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above directional words are not used to limit the present invention.

[0025] In order to solve the problem of serious environmental pollution caused by a negative pressure pumping device for a lubricating oil tank in the prior art, the utility model provides a negative pressure pumping device for a lubricating oil tank and a steam turbine unit having the same.

[0026] like Figure 1 As shown, the negative pressure extraction device for the lubricating oil tank includes an extraction mechanism 20, a noise reduction mechanism 30 and an oil-gas separation mechanism 40. At least a portion of the extraction mechanism 20 is used to connect to the lubricating oil tank 10 to extract oil and gas; the noise reduction mechanism 30 is connected to the extraction mechanism 20; and the oil-gas separation mechanism 40 is connected to one end of the noise reduction mechanism 30 away from the extraction mechanism 20.

[0027] To improve the safety of the lubricating oil tank negative pressure pumping device, the core of the lubricating oil tank negative pressure pumping device of the present application comprises three modules: an extraction mechanism 20, a noise reduction mechanism 30, and an oil-gas separation mechanism 40, which are connected in sequence. A portion of the extraction mechanism 20 is directly connected to the lubricating oil tank 10 to extract oil and gas. The noise generated during the oil and gas extraction process is effectively absorbed by the noise reduction mechanism 30, greatly reducing noise pollution. The oil-gas separation mechanism 40 is located at the end of the noise reduction mechanism 30 away from the extraction mechanism 20, and separates the oil and gas extracted from the lubricating oil tank 10, recovers the lubricating oil, and discharges non-condensable gas at the same time, saving resources while selectively controlling the discharged gas and reducing air pollution. The extraction mechanism 20, noise reduction mechanism 30, and oil-gas separation mechanism 40 of the lubricating oil tank negative pressure pumping device of the present application work together, significantly improving the safety of the lubricating oil tank negative pressure pumping device and the comfort of the working environment, effectively controlling noise pollution and air pollution, and providing a safer, more environmentally friendly, and economical solution for maintaining negative pressure inside the lubricating oil tank.

[0028] like Figure 1 As shown, the extraction mechanism 20 includes an extraction assembly that connects the lubricating oil tank 10 and the noise reduction mechanism 30 to extract oil and gas. The extraction mechanism 20 includes an extraction assembly, and the lubricating oil tank negative pressure extraction device directly connects the lubricating oil tank 10 and the noise reduction mechanism 30 through the extraction assembly. After the oil and gas are extracted from the extraction assembly, they immediately enter the noise reduction mechanism 30. After passing through the noise reduction mechanism 30, the noise during the extraction process is significantly reduced, creating a more comfortable working environment for the operator. Furthermore, the direct connection between the extraction assembly and the noise reduction mechanism 30 simplifies the structure of the lubricating oil tank negative pressure extraction device, reduces maintenance costs, and improves the cost-effectiveness and reliability of the lubricating oil tank negative pressure extraction device.

[0029] Optionally, the noise reduction mechanism 30 may include a muffler, which can significantly reduce the noise during the extraction process, creating a more comfortable working environment for the operator, while also reducing the impact of the noise on the surrounding area.

[0030] like Figure 1 As shown, the extraction assembly includes a venturi tube 22, with the lubricating oil tank 10 and a noise reduction mechanism 30 located at either end of the venturi tube 22. The two ends of the venturi tube 22 are the inlet and outlet, respectively. The lubricating oil tank 10 is located near the inlet of the venturi tube 22. As air flows through the contraction section of the venturi tube 22, the increased flow velocity causes a decrease in pressure. The oil and gas within the lubricating oil tank 10 are attracted by the pressure difference and enter the venturi tube 22 through the inlet. The noise reduction mechanism 30 is located at the outlet of the venturi tube 22, reducing the noise generated during the flow of oil and gas discharged from the venturi tube 22. The noise reduction mechanism 30 achieves the noise reduction effect by absorbing or attenuating sound waves. This layout ensures that after being extracted from the lubricating oil tank 10, the oil and gas smoothly pass through the noise reduction mechanism 30 and ultimately enter the subsequent oil-gas separation mechanism 40, ensuring an efficient, safe, and environmentally friendly oil-gas separation process. The venturi tube 22 not only achieves the purpose of efficiently extracting oil and gas from the lubricating oil tank 10, but also avoids the safety risks such as electric sparks and noise caused by the use of an oil mist blower, thereby improving the safety of the lubricating oil tank negative pressure extraction device.

[0031] It should be noted that the Venturi tube 22 has a Venturi effect. When the flowing air passes through the Venturi tube 22, it follows the basic principles of fluid dynamics. In particular, in the necking part of the Venturi tube 22, the fluid velocity increases significantly, causing the static pressure in this area to drop significantly, thereby attracting oil and gas from the lubricating oil tank 10 to flow through the Venturi tube 22.

[0032] like Figure 1 As shown, the extraction mechanism 20 also includes a power assembly connected to the end of the venturi tube 22 near the lubricating oil tank 10. The extraction mechanism 20 not only includes the extraction assembly of the venturi tube 22 but also the power assembly that provides power for the entire extraction process. By connecting to the end of the venturi tube 22 near the lubricating oil tank 10, the power assembly ensures that the venturi tube 22 can generate a sufficient pressure differential under appropriate conditions to smoothly extract oil and gas from the lubricating oil tank 10.

[0033] like Figure 1As shown, the power assembly includes an instrument air source 23, which is connected to the end of the venturi tube 22 near the lubricating oil tank 10 to supply instrument air to the venturi tube 22. The instrument air source 23 delivers pressured instrument air to the venturi tube 22, leveraging the flow characteristics of the instrument air to drive the entire vacuum pumping process. The use of instrument air significantly reduces safety hazards associated with electrical drives, such as the risk of fire or explosion caused by electrical sparks. It also reduces energy consumption in the lubricating oil tank vacuum pumping device, meeting the requirements for safety and cost-effectiveness in production.

[0034] Preferably, the pressure of the instrument air source 23 is set at about 0.8 MPa, which can not only ensure the air flow velocity and pressure difference required for the normal operation of the venturi tube 22, but also avoid damage to the negative pressure pumping device of the lubricating oil tank due to excessive pressure.

[0035] Optionally, the power assembly also includes a compressed air source 26, which is connected to the end of the venturi tube 22 near the lubricating oil tank 10 to supply compressed air to the venturi tube 22. The compressed air source 26 serves as a backup or supplemental power source, powering the venturi tube 22 and facilitating efficient extraction of oil and vapor from the lubricating oil tank 10. The compressed air source 26 provides sufficient compressed air to ensure that the venturi tube 22 can generate and maintain the required pressure differential, thereby enabling the lubricating oil tank negative pressure extraction device to continuously and stably extract oil and vapor.

[0036] like Figure 1 As shown, the power assembly also includes a first check valve 25 and a second check valve 28. The first check valve 25 is connected between the instrument air source 23 and the venturi tube 22, while the second check valve 28 is connected between the compressed air source 26 and the venturi tube 22. The first check valve 25, located on the connecting pipe between the instrument air source 23 and the venturi tube 22, effectively prevents oil, gas, or air inside the venturi tube 22 from flowing back into the instrument air source 23 when the extraction process ends or when the system pressure changes, thereby preventing contamination or damage to the instrument air source 23 and ensuring the safe and stable operation of the instrument air source 23. Similarly, the second check valve 28 prevents oil, gas, and air inside the venturi tube 22 from flowing back into the compressed air source 26, protecting the compressed air source 26 from contamination and maintaining its normal operating conditions. Furthermore, the second check valve 28 prevents air crosstalk between different air sources when the system switches or when all air sources are used simultaneously, ensuring the independent and safe operation of the lubricating oil tank negative pressure extraction device.

[0037] Optionally, an instrument air regulating valve 24 is provided between the first check valve 25 and the instrument air source 23, and a self-operated regulating valve 27 is provided between the second check valve 28 and the compressed air source 26. The instrument air regulating valve 24 is responsible for opening and closing the instrument air source 23, while the self-operated regulating valve 27 is responsible for opening and closing the compressed air source 26, automatically adjusting the valve opening according to the pressure.

[0038] Optionally, the instrument air from the instrument air source 23 and the compressed air from the compressed air source 26 are combined into the same pipeline and pass through the air inlet valve 21. The air inlet valve 21 controls the air to enter the venturi tube 22 and adjusts the opening to control the air flow.

[0039] like Figure 1 As shown, the oil-gas separation mechanism 40 includes at least one oil-gas separation assembly 41. One end of the oil-gas separation assembly 41 is connected to the end of the noise reduction mechanism 30 away from the extraction mechanism 20. The oil-gas separation assembly 41 is capable of separating oil and gas into condensable matter and non-condensable gas. The oil-gas separation assembly 41 is located on the side of the noise reduction mechanism 30 away from the extraction mechanism 20. This ensures that after the oil and gas are reduced in noise by the noise reduction mechanism 30, they can directly enter the oil-gas separation assembly 41 for separation and processing, reducing the residence time of the oil and gas in the pipeline and improving separation efficiency. When the oil and gas flow through the oil-gas separation assembly 41, condensable matter, namely condensed lubricating oil, is collected at the bottom of the oil-gas separation assembly 41, while the non-condensable gas is discharged upward through the release port 44.

[0040] Specifically, when oil and gas flow through the oil-gas separation assembly 41, denser oil droplets settle downward under gravity or are flung toward the wall of the oil-gas separation assembly 41 under centrifugal force, while air continues to be discharged upward through the release port 44 of the oil-gas separation assembly 41. Through this process, the lubricating oil is collected at the bottom of the separator, while the non-condensable gas is discharged, achieving effective separation of oil and gas.

[0041] like Figure 1As shown, the oil-gas separation mechanism 40 includes at least two sets of oil-gas separation components 41 and at least one set of three-way switching valves 42 connected between the noise reduction mechanism 30 and the two sets of oil-gas separation components 41. The at least two sets of oil-gas separation components 41 provide sufficient backup options for the lubricating oil tank negative pressure pumping device, ensuring that even if one set of oil-gas separation components 41 requires maintenance or cleaning, the other set can continue to operate, maintaining the continuity of oil-gas separation and thus ensuring the stable operation of the lubricating oil tank negative pressure pumping device. The three-way switching valve 42 allows for automatic or manual switching between the two sets of oil-gas separation components 41. When one set of oil-gas separation components 41 reaches saturation, the three-way switching valve 42 redirects the oil and gas flow, directing it into the other set of oil-gas separation components 41. This significantly improves the flexibility and maintenance efficiency of the lubricating oil tank negative pressure pumping device and avoids the risk of downtime due to maintenance of a single oil-gas separation component 41.

[0042] The present invention also provides a steam turbine unit including the aforementioned lubricating oil tank negative pressure pumping device. The steam turbine unit incorporating the lubricating oil tank negative pressure pumping device not only resolves the safety issues caused by oil and gas accumulation in the lubricating oil tank 10, but also achieves comprehensive improvements in economic efficiency, reliability, and environmental performance, significantly enhancing the safety performance of the steam turbine unit and facilitating operation of the steam turbine unit with low energy consumption and reduced safety risks.

[0043] Example 1

[0044] like Figure 1 As shown, the lubricating oil tank negative pressure extraction device of embodiment 1 of the present application is described.

[0045] Specifically, when the lubricating oil tank 10 is under positive pressure, the oil and gas inlet valve 11 between the lubricating oil tank 10 and the venturi tube 22 is moderately open. The first check valve 25 is opened to allow instrument air from the 0.8 MPa instrument air source 23 to serve as the power source. The second check valve 28 is opened to allow compressed air from the compressed air source 26 to be supplemented. The air inlet valve 21 is slowly opened, and the opening of the air inlet valve 21 is adjusted according to the pressure differential of the lubricating oil tank 10. Air and oil gas are then reduced in noise by the noise reduction mechanism 30 and enter the oil-gas separation mechanism 40. During the noise reduction process, some condensed lubricating oil enters the oil-gas separation assembly 41 through the muffler drain valve 31. The air and oil gas are separated within the oil-gas separation assembly 41, and the condensed lubricating oil is recovered through the opened lubricating oil discharge valve 43, while the non-condensable gas is discharged through the release port 44.

[0046] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0047] 1. In order to improve the safety of the lubricating oil tank negative pressure pumping device, the core of the lubricating oil tank negative pressure pumping device of the present application is composed of three modules: an extraction mechanism 20, a noise reduction mechanism 30, and an oil-gas separation mechanism 40, which are connected in sequence. A part of the extraction mechanism 20 is directly connected to the lubricating oil tank 10 to extract the oil and gas. The noise generated during the oil and gas extraction process is effectively absorbed or weakened by the noise reduction mechanism 30. The oil-gas separation mechanism 40 is located at the end of the noise reduction mechanism 30 away from the extraction mechanism 20, and separates the oil and gas extracted from the lubricating oil tank 10, recovers the lubricating oil, and discharges non-condensable gas at the same time. The extraction mechanism 20, the noise reduction mechanism 30, and the oil-gas separation mechanism 40 of the lubricating oil tank negative pressure pumping device of the present application work together, which not only significantly improves the safety of the lubricating oil tank negative pressure pumping device and the comfort of the working environment, but also effectively controls noise pollution and air pollution, and provides a safer, more environmentally friendly and economical solution.

[0048] 2. The venturi tube 22 not only achieves the purpose of efficiently extracting oil and gas from the lubricating oil tank 10, but also avoids the safety risks such as electric sparks and noise caused by the use of an oil mist blower, thereby improving the safety of the lubricating oil tank negative pressure extraction device.

[0049] 3. The lubricating oil tank vacuum pumping device directly connects the lubricating oil tank 10 and the noise reduction mechanism 30 through the extraction assembly. After being extracted from the extraction assembly, the oil and gas immediately enter the noise reduction mechanism 30. Passing through the noise reduction mechanism 30, the noise during the extraction process is significantly reduced, creating a more comfortable working environment for the operator. Furthermore, the direct connection between the extraction assembly and the noise reduction mechanism 30 simplifies the structure of the lubricating oil tank vacuum pumping device, reduces maintenance costs, and improves the cost-effectiveness and reliability of the lubricating oil tank vacuum pumping device.

[0050] Obviously, the embodiments described above are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, tasks, devices, components and / or combinations thereof.

[0052] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0053] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A negative pressure pumping device for a lubricating oil tank, characterized in that: include: an extraction mechanism (20), at least a portion of which is connected to the lubricating oil tank (10) to extract oil and gas; a noise reduction mechanism (30), the noise reduction mechanism (30) being in communication with the extraction mechanism (20); An oil-gas separation mechanism (40) is connected to an end of the noise reduction mechanism (30) away from the extraction mechanism (20).

2. The negative pressure pumping device for the lubricating oil tank according to claim 1, characterized in that: The extraction mechanism (20) includes an extraction component, and the extraction component can connect the lubricating oil tank (10) and the noise reduction mechanism (30) to extract the oil and gas.

3. The negative pressure pumping device for the lubricating oil tank according to claim 2, characterized in that: The extraction assembly comprises a venturi tube (22), and the lubricating oil tank (10) and the noise reduction mechanism (30) are respectively located at two ends of the venturi tube (22).

4. The lubricating oil tank negative pressure extraction device according to claim 3, characterized in that: The extraction mechanism (20) further includes a power assembly, which is connected to one end of the venturi tube (22) close to the lubricating oil tank (10).

5. The negative pressure pumping device for the lubricating oil tank according to claim 4, characterized in that: The power assembly includes an instrument air source (23), which is connected to one end of the venturi tube (22) close to the lubricating oil tank (10) to input instrument air into the venturi tube (22).

6. The negative pressure pumping device for the lubricating oil tank according to claim 5, characterized in that: The power assembly further comprises a compressed air source (26), which is connected to one end of the venturi tube (22) close to the lubricating oil tank (10) to input compressed air into the venturi tube (22).

7. The negative pressure pumping device for a lubricating oil tank according to claim 6, characterized in that: The power assembly further comprises a first check valve (25) and a second check valve (28), wherein the first check valve (25) is connected between the instrument air source (23) and the venturi tube (22), and the second check valve (28) is connected between the compressed air source (26) and the venturi tube (22).

8. The lubricating oil tank negative pressure extraction device according to any one of claims 1 to 7, characterized in that: The oil-gas separation mechanism (40) includes at least one group of oil-gas separation components (41), one end of the oil-gas separation component (41) is connected to an end of the noise reduction mechanism (30) away from the extraction mechanism (20), and the oil-gas separation component (41) can separate the oil and gas into condensable objects and non-condensable gas.

9. The negative pressure pumping device for a lubricating oil tank according to claim 8, characterized in that: The oil-gas separation mechanism (40) includes at least two groups of oil-gas separation components (41), and the oil-gas separation mechanism (40) further includes at least one group of three-way switching valves (42). The three-way switching valves (42) are connected between the noise reduction mechanism (30) and the two groups of oil-gas separation components (41).

10. A steam turbine unit, characterized in that: The invention comprises the lubricating oil tank negative pressure extraction device according to any one of claims 1 to 9.

Images