A device and method for preventing oil slinging from a pumped storage thrust bearing

Abstract

This invention relates to the field of pumped-storage technology, and provides a device and method for preventing oil spillage in pumped-storage thrust bearings. The device features an integrally formed spiral oil guide groove on the surface of a mirror plate, which guides the oil to form a stable directional flow using the spiral angle of the groove. A centrifugal separation chamber is located downstream of the spiral oil guide groove, using centrifugal force to separate the oil and oil mist transported from the groove. A negative pressure return channel is located downstream of the centrifugal separation chamber, using vacuum negative pressure technology to capture residual oil mist and guide it back to the oil storage chamber. This design significantly reduces oil mist leakage, fundamentally solving the problem of poor anti-spillage performance in traditional single-barrier anti-spillage structures, extending maintenance cycles, reducing downtime frequency, and lowering operation and maintenance costs.

Description

Technical Field

[0001] This invention relates to the field of pumped storage technology, specifically to a pumped storage thrust bearing anti-oil-slinging device and method. Background Technology

[0002] As a critical peak-shaving and energy storage device in the power system, the long-term stable operation of the thrust bearing of pumped storage units under high-speed rotation and heavy-load conditions is crucial for ensuring grid security and power plant economy. Thrust bearings rely on a lubricating oil film for friction reduction and wear resistance. However, under the combined effects of centrifugal force, temperature gradient, and dynamic load, the lubricating oil is easily ejected, forming oil mist. This not only causes lubricant loss and environmental pollution but may also seep into electrical components, leading to serious accidents such as insulation failure.

[0003] Among them, thrust bearing anti-slip oil technology mainly focuses on actively guiding the flow behavior of lubricating oil and suppressing the source of oil mist generation mechanism. Current engineering practices commonly employ mechanical barrier structures consisting of oil baffles, gaskets, washers, and contact-type lower oil baffles, limiting the oil overflow path through preset fixed gaps. While this type of solution is structurally simple, it reveals systemic defects in actual complex operating environments. For example, oil flow control is coarse; the oil baffles cannot effectively organize the oil flow direction at high speeds, easily inducing turbulence and increasing the oil film pressure difference by approximately 40%, significantly weakening the anti-slip effectiveness, resulting in short maintenance cycles (3–18 months), frequent downtime, and high operation and maintenance costs. Summary of the Invention

[0004] Therefore, the present invention aims to solve the problems of poor anti-spillage performance, resulting in short maintenance cycles (3–18 months), frequent downtime, and high operation and maintenance costs in the prior art, which uses a mechanical barrier structure consisting of an oil baffle plate, a gasket, a gasket, and a contact-type lower oil baffle to limit the oil overflow path by a preset fixed gap. The present invention provides an anti-spillage device and method for pumped storage thrust bearings.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: On one hand, the present invention provides a pumped storage thrust bearing anti-oil-slinging device, comprising: a base; a rotor shaft rotatably mounted on the base about its own axis; a thrust head sleeved on the rotor shaft for bearing and transmitting axial load; a thrust bearing mounted on the base and sleeved on the rotor shaft; a mirror plate disposed on the side of the thrust head facing the thrust bearing, the side of the mirror plate facing the thrust bearing having an integrally formed spiral oil guide groove; and a centrifugal separation chamber located downstream of and connected to the spiral oil guide groove, the centrifugal separation chamber having a first outlet and a second outlet, the centrifugal separation chamber having an annular structure, and utilizing the principle of centrifugal force to separate oil from the spiral oil guide groove. The system includes: a tank for conveying oil and oil mist; a negative pressure reflux channel located downstream of the centrifugal separation chamber and connected to the first outlet, the negative pressure reflux channel being arranged around the periphery of the centrifugal separation chamber in the circumferential direction; an oil storage chamber, the outlet of the negative pressure reflux channel being connected to the oil storage chamber, oil mist flowing back to the oil storage chamber via the negative pressure reflux channel; a second outlet of the centrifugal separation chamber being connected to the oil storage chamber, oil flowing back to the oil storage chamber via the centrifugal separation chamber; and an oil storage chamber connected to the spiral oil guide groove, where the returned oil mist and oil are mixed and cooled before being re-transported to the spiral oil guide groove for cooling the thrust head.

[0006] Furthermore, the spiral angle of the spiral oil guide groove is in the range of 28°-32°; and / or, the ratio of the groove depth to the width of the spiral oil guide groove is set to 1:2.

[0007] Furthermore, the internal diameter-to-depth ratio of the centrifuge chamber is designed to be 1:1.5; and / or, the inner wall of the centrifuge chamber adopts a three-stage stepped design, with each stage being 1 / 3 of the total depth, to form a continuous multi-stage deceleration buffer zone.

[0008] Furthermore, the vacuum degree inside the negative pressure return channel is maintained at ≥0.05MPa; and / or, the inner wall of the negative pressure return channel is provided with a plurality of guide vanes evenly distributed along the circumference, and the installation angle range of the guide vanes is 15°-25°.

[0009] Furthermore, the pumped storage thrust bearing anti-oil-slinging device also includes a guide pipe, and the negative pressure return channel is connected to the oil storage chamber through the guide pipe; the inner diameter of the guide pipe is in the range of 20-30mm, and the inner surface roughness Ra of the guide pipe is ≤0.1μm.

[0010] Furthermore, the inner wall surfaces of the spiral oil guide groove and the centrifugal separation chamber are laser microtextured to form a regular micro-pit array structure, so that when the oil passes through the micro-pit array structure, a microscopic oil film can be generated on the microtextured surface; and / or, the inner wall surfaces of the spiral oil guide groove and the centrifugal separation chamber are provided with a superoleophobic coating.

[0011] Furthermore, the pumped storage thrust bearing anti-oil-slinging device also includes: a temperature sensor array, located at the inlet of the centrifugal separation chamber, for real-time acquisition of oil temperature data entering the centrifugal separation chamber; a PLC controller, electrically connected to the temperature sensor array, for generating corresponding control signals based on the oil temperature data fed back by the temperature sensor array; a piezoelectric actuator, electrically connected to the PLC controller, for converting the control signals sent by the PLC controller into mechanical displacement; and a variable throttle valve, located on the pipeline between the oil storage chamber and the external oil source, the variable throttle valve being connected to the piezoelectric actuator and controlled by the piezoelectric actuator to regulate the oil flow.

[0012] Furthermore, the control algorithm of the PLC controller includes a temperature change rate prediction module, which establishes a time series model based on historical temperature data to predict temperature trends in advance and adjust the control signal accordingly.

[0013] On the other hand, the present invention also provides a method for preventing oil slinging in a pumped storage thrust bearing, including the oil slinging device for pumped storage thrust bearing described in any one of the above-mentioned methods; the method includes the following steps: guiding the oil to form a directional flow through a spiral oil guide groove to initially suppress the tendency of centrifugal oil slinging; allowing the initially guided oil to enter a centrifugal separation chamber to separate the oil and oil mist using the principle of centrifugal force; capturing the residual oil mist in the centrifugal separation chamber under vacuum conditions through a negative pressure reflux channel; and guiding the captured oil mist back to the oil storage chamber.

[0014] Furthermore, the method for preventing oil slinging from the pumped storage thrust bearing also includes the following steps: using a temperature sensor array to acquire real-time oil temperature data for cooling and feeding it back to the PLC controller; using the PLC controller to analyze the oil temperature data and output a control signal; using a piezoelectric actuator to adjust the opening of the variable throttle valve according to the control signal output by the PLC controller, so that the oil film temperature fluctuation is controlled within ±2℃.

[0015] The technical solution of this invention has the following advantages: The oil spill prevention device for pumped storage thrust bearings provided by this invention features an integrally formed spiral oil guide groove on the surface of a mirror plate. The spiral angle of the groove guides the oil to form a stable, directional flow. A centrifugal separation chamber is located downstream of the spiral oil guide groove, using centrifugal force to separate the oil and oil mist transported from the groove. A negative pressure return channel is located downstream of the centrifugal separation chamber, using vacuum negative pressure technology to capture residual oil mist and guide it back to the oil storage chamber. This design significantly reduces oil mist leakage, fundamentally solving the problem of poor anti-spill performance in traditional single-barrier anti-spill structures, extending maintenance cycles, reducing downtime frequency, and lowering operation and maintenance costs. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the anti-oil-slinging device for the pumped storage thrust bearing in an embodiment of the present invention; Figure 2 This is a schematic diagram of the mirror plate in the anti-oil-slinging device for the pumped storage thrust bearing in an embodiment of the present invention; Figure 3 This is a schematic flowchart of the method for preventing oil spillage from the thrust bearing of a pumped storage power plant in an embodiment of the present invention. Figure 4 This is a flowchart illustrating the temperature control logic in the method for preventing oil spillage from a pumped storage thrust bearing in an embodiment of the present invention.

[0018] Explanation of reference numerals in the attached figures: 1. Base; 2. Rotor shaft; 3. Thrust head; 4. Thrust bearing; 5. Mirror plate; 501. Spiral oil guide groove; 6. Centrifugal separation chamber; 601. First outlet; 602. Second outlet; 7. Negative pressure return channel; 8. Oil storage chamber; 9. Oil supply channel; 10. Temperature sensor array; 11. PLC controller; 12. Piezoelectric actuator; 13. Variable throttle valve. Detailed Implementation

[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and defined, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Example 1 Figure 1 This is a schematic diagram of an anti-oil-slinging device for pumped-storage thrust bearings provided in one embodiment of the present invention. This embodiment provides an integrated and high-efficiency anti-oil-slinging device for pumped-storage thrust bearings, aiming to fundamentally solve the systemic technical problems caused by the use of traditional mechanical barrier structures (such as oil baffles, gaskets, etc.) in the prior art, such as poor anti-slinging efficiency, short maintenance cycle (usually only 3 to 18 months), frequent downtime, and high operation and maintenance costs.

[0024] like Figure 1 , Figure 2 As shown, the pumped storage thrust bearing anti-oil-throwing device mainly includes: a base 1, a rotor shaft 2, a thrust head 3, a thrust bearing 4, a mirror plate 5, a centrifugal separation chamber 6, a negative pressure reflux channel 7, and an oil storage chamber 8.

[0025] The base 1 serves as the fundamental support structure for the entire device, used to install and secure all other components. The rotor shaft 2 is the core element for power transmission; it is rotatably mounted on the base 1 via bearings or other means. In actual operation, the rotor shaft 2 rotates at high speed under the drive of a turbine or electric generator, generating a strong centrifugal force field, which is the main environmental factor inducing oil slickness.

[0026] The thrust head 3 is mounted and fixed on the rotor shaft 2 and rotates with it. Its main function is to bear and transmit the huge axial load from the rotor shaft 2 (for example, thousands of kilonewtons in large pumped storage units) and evenly transfer this load to the thrust bearing 4 below. The lower end face of the thrust head 3 is usually a precision-machined flat surface used to mount the mirror plate 5.

[0027] The thrust bearing 4 is mounted on the base 1 and sleeved around the rotor shaft 2. The thrust bearing 4 is a key component that bears the axial thrust and typically consists of several sector-shaped bearing shells. During operation, a very thin lubricating oil film forms between the thrust bearing 4 and the high-speed rotating mirror plate 5. This oil film is crucial for achieving friction reduction, wear resistance, and load bearing. However, this oil film is also the source of oil splattering problems.

[0028] The mirror plate 5 is a disc-shaped component with extremely high flatness requirements. It is fixedly mounted on the side of the thrust head 3 facing the thrust bearing 4, meaning the mirror plate 5 rotates at high speed together with the thrust head 3 and the rotor shaft 2. The lower surface of the mirror plate 5 (the side facing the thrust bearing 4) is the key working surface for forming and maintaining the lubricating oil film. One of the core improvements of this invention is that a spiral oil guide groove 501 is integrally formed on the working surface of the mirror plate 5 facing the thrust bearing 4. Unlike traditional smooth mirror plates or simple straight grooves, this spiral oil guide groove 501 has a precisely designed spiral angle, and its function is not merely to contain oil, but to actively and precisely guide the flow of oil.

[0029] Specifically, the spiral angle of the spiral oil guide groove 501 is optimized to be between 28° and 32°. This angle range is not arbitrarily selected, but is the result of in-depth analysis and simulation optimization of the fluid dynamics characteristics of the oil under high-speed rotation. When the mirror plate 5 rotates at its rated speed, the spiral groove at this specific angle can generate a centripetal force component opposite to the direction of centrifugal force. This centripetal force component can effectively counteract or weaken the centrifugal force tendency to throw the oil outward due to high-speed rotation, thereby confining the oil within the channel and forcing it to form a stable and orderly laminar flow along the path defined by the spiral groove towards the center and edge of the mirror plate 5. This active guidance method fundamentally changes the disordered and turbulent state of oil throwing out, representing a breakthrough from the traditional passive blocking approach. At the same time, in order to further optimize the flow characteristics of the oil, reduce flow resistance, and ensure sufficient guiding cross-section, the channel depth to width ratio of the spiral oil guide groove 501 is preferably set to 1:2. This proportional design gives the channel a wide and shallow geometry, which is conducive to the formation of a stable, low-resistance flow boundary layer for the oil in the channel, reducing the probability of turbulence.

[0030] like Figure 1As shown, a centrifugal separation chamber 6 is located at the end of the spiral oil guide channel 501, i.e., downstream of it. This centrifugal separation chamber 6 is connected to the outlet of the spiral oil guide channel 501 and is an annular cavity structure arranged around the rotor shaft 2. The core function of the centrifugal separation chamber 6 is to efficiently separate the oil-gas mixture (i.e., a mixture of oil and oil mist) transported from the spiral oil guide channel 501 using the principle of centrifugal force. Its specific working process is as follows: The mixed fluid carrying oil and fine oil mist enters the centrifugal separation chamber 6 with a certain initial velocity under the guidance of the spiral oil guide channel 501. Because the centrifugal separation chamber 6 is an annular structure, the mixed fluid is forced into high-speed circular motion within it. During this process, relatively clean air and oil mist are thrown towards the outer wall of the centrifugal separation chamber 6, while oil droplets tend towards the central area.

[0031] To achieve this separation process more efficiently, the internal structure of the centrifuge chamber 6 has undergone several optimization designs. For example, its internal diameter-to-depth ratio (i.e., the ratio of inner diameter to depth) has been optimized to 1:1.5. This ratio ensures sufficient separation space while optimizing the compactness of the structure and achieving an ideal balance between the rotational speed and residence time of the mixed fluid within the chamber, thereby maximizing separation efficiency. Furthermore, the inner wall of the centrifuge chamber 6 can adopt a three-stage stepped design, with the height of each step approximately one-third of the total depth of the centrifuge chamber. This unique multi-stage structure essentially forms a continuous multi-stage deceleration buffer zone. When the mixed fluid flows through each step, its flow path changes abruptly, forming local eddies, which effectively prolongs the residence time of oil mist within the separation chamber and increases the opportunity for oil droplets to collide with and adhere to the wall surface, significantly enhancing the separation effect between oil and oil mist.

[0032] Based on the above separation mechanism, the centrifugal separation chamber 6 has two outlets: a first outlet 601 and a second outlet 602. The separated, denser liquid oil flows directly back to the lower oil storage chamber 8 through the second outlet 602, completing the direct recovery of the oil. The gas, which still contains a small amount of residual oil mist after the initial separation, is discharged from the first outlet 601 of the centrifugal separation chamber 6 and enters the next stage of processing.

[0033] The next stage of processing is the negative pressure reflux channel 7. The negative pressure reflux channel 7 is located downstream of the centrifuge chamber 6 and is connected to the first outlet 601. From... Figure 1As can be seen, the negative pressure reflux channel 7 is arranged around the periphery of the centrifugal separation chamber 6 along its circumferential direction, forming a ring-shaped or nearly ring-shaped closed pipe. The key technical feature of this channel is that it maintains a stable negative pressure environment, i.e., a vacuum degree. Preferably, the vacuum degree maintained inside the negative pressure reflux channel 7 is not less than 0.05 MPa. This vacuum degree can be continuously maintained by an external micro vacuum pump system controlled by a PLC controller 11.

[0034] The establishment of a negative pressure environment has crucial technical effects. First, it creates a powerful suction force that actively draws the gas containing residual oil mist discharged from the first outlet 601 into the negative pressure return channel 7, preventing the oil mist from escaping from any gaps inside the equipment. Second, under negative pressure, the flow velocity of the oil mist is increased, and the flow state is more controllable. More ingeniously, the inner wall of the negative pressure return channel 7 is also equipped with several circumferentially evenly distributed guide vanes. These guide vanes are typically arranged in groups of 6 to 8, and their installation angle (i.e., the angle between the vane and the airflow direction) is precisely controlled within the range of 15° to 25°. When the airflow passes through these guide vanes, a series of controllable local vortices are generated. These vortices greatly increase the probability of residual oil mist colliding and adsorbing with the channel wall and vane surfaces, thereby significantly improving the oil mist collection efficiency. The oil mist drawn in and captured by the negative pressure gradually condenses into small oil droplets within the channel and is eventually guided to the outlet of the negative pressure return channel 7 along with the airflow.

[0035] The outlet of the negative pressure reflux channel 7 can be connected to the oil storage chamber 8 via a dedicated guide pipe. To further reduce flow resistance and prevent oil mist from re-adhering during transport, the inner diameter of this guide pipe is preferably 20 to 30 mm, and its inner surface is ultra-precision polished to ensure a surface roughness Ra value of no more than 0.1 micrometers (μm). This smooth surface allows oil mist and condensed micro-droplets to flow smoothly and quickly into the oil storage chamber 8.

[0036] The oil reservoir 8 is a container in the system used for storing, mixing, and cooling lubricating oil. As mentioned earlier, it receives media from two sources: liquid oil from the second outlet 602 of the centrifugal separation chamber 6, and oil mist and gas collected and condensed from the negative pressure return channel 7. These two media undergo mixing, cooling, and defoaming treatment within the oil reservoir 8. Internal components such as baffles, cooling coils, and oil-gas separators can be installed inside the oil reservoir 8 to promote the precipitation of bubbles in the oil and maintain the oil within its optimal operating temperature range (e.g., through heat exchange via a circulating cooling water system).

[0037] Finally, the entire system forms a closed-loop oil circulation. The oil storage chamber 8 and the spiral oil guide groove 501 are connected through the oil supply channel 9. Driven by an external oil pump (not shown in the figure), the lubricating oil in the oil storage chamber 8, after being cooled, mixed, and purified, is transported back to the spiral oil guide groove 501 on the surface of the mirror plate 5 for lubrication and cooling of the thrust head 3 and the thrust bearing 4. In this way, a complete closed-loop management of lubricating oil from supply, use, discharge, recovery, and resupply is achieved, greatly reducing lubricating oil consumption and leakage.

[0038] This embodiment employs a three-stage flow-guiding and oil-slinging prevention architecture that organically combines and synergistically utilizes a spiral oil guide groove for active flow guidance, a centrifugal separation chamber for efficient separation, and a negative pressure reflux channel for vacuum capture. This fundamentally overturns the traditional approach of simple isolation or flow guidance. The spiral oil guide groove 501 suppresses the tendency of centrifugal oil slinging at the source, the centrifugal separation chamber 6 achieves the main separation of oil and oil mist during the process, and the negative pressure reflux channel 7 performs the final capture of residual trace amounts of oil mist. The three elements work together in a progressive manner, resulting in a reduction of oil mist leakage by more than 80% compared to traditional technologies. This significantly extends the equipment maintenance cycle (from the traditional 3-18 months to 24-36 months), greatly reduces the frequency of unplanned downtime caused by lubricating oil leakage and oil mist contamination, and effectively lowers the overall life-cycle maintenance cost of the equipment.

[0039] Example 2 Based on Example 1 above, this embodiment further optimizes and improves the microstructure and surface characteristics of key oil flow surfaces such as the spiral oil guide groove 501 and the centrifugal separation chamber 6, so as to control the oil behavior more precisely at the micro level and improve the anti-oil-slinging effect and system efficiency.

[0040] One improvement in this embodiment is that both the spiral oil guide groove 501 and the inner wall surface of the centrifugal separation chamber 6 are subjected to laser microtexturing treatment to form a regularly arranged array of micropits on their surfaces. Specifically, this processing technology can employ a nanosecond or femtosecond pulsed laser processing system. During the processing, by precisely controlling the laser power, frequency, scanning path, and focal position, micropits with a diameter of approximately 40 to 60 micrometers and a depth of approximately 15 to 25 micrometers can be processed on the metal substrate surface. These micropits are arranged in a regular array, such as a square array or a hexagonal array, with the center-to-center spacing (pitch) between adjacent micropits controlled between 80 and 120 micrometers. To ensure processing quality and prevent surface oxidation, the entire laser processing process can be carried out in an inert gas protective atmosphere such as argon.

[0041] The technological effects of this laser microtexturing treatment are multifaceted and exhibit significant synergistic properties. Firstly, the uniformly distributed array of micro-pits creates a microscopic hydraulic bearing effect on the surface. When lubricating oil flows through these pits, a portion of the oil is stored within them, forming tiny, localized hydrodynamic oil films under relative motion or pressure. These ubiquitous microscopic oil films can transform some of the direct solid friction between traditional metal surfaces into much lower fluid friction. Experiments show that after this treatment, the overall friction coefficient of the thrust bearing 4 can be significantly reduced from approximately 0.15 in the traditional design to below 0.03, demonstrating a remarkably significant friction reduction effect and decreasing frictional power consumption by approximately 80%. This is of great significance for energy conservation and consumption reduction in large motors.

[0042] Secondly, these micro-pit arrays can effectively capture and retain tiny oil droplets or oil mist particles that may escape from the main oil film under high-speed shearing. When these free oil mist particles move into the micro-pit area, they are pinned within the pits by surface tension and capillary force, thereby reducing the concentration of free oil mist and inhibiting its further outward diffusion. This is equivalent to adding an oil mist capture barrier at the microscale, forming a cross-scale synergistic anti-oil-slinging effect with the macroscopic centrifugal separation chamber 6 and negative pressure reflux channel 7.

[0043] As a supplement or alternative to the aforementioned laser microtexturing treatment, another improvement in this embodiment is the application of a superoleophobic coating to the inner wall surfaces of the spiral oil guide groove 501 and the centrifugal separation chamber 6. This superoleophobic coating can be made of a material with extremely low surface energy, such as a fluorosilyl compound. The coating can be formed using a vapor deposition process (such as plasma-enhanced chemical vapor deposition, PECVD). During deposition, the temperature within the reaction chamber can be maintained at 150°C to 200°C, and the deposition pressure controlled at 10 Pa to 50 Pa. Under these process conditions, the final coating thickness is approximately 5 to 8 micrometers, and it can form a strong chemical bond with the metal substrate. The coating hardness can reach 6H (pencil hardness), exhibiting excellent wear resistance and long-term operational reliability.

[0044] The core function of this superoleophobic coating lies in its unique wettability. After treatment, the contact angle between the surface and lubricating oil can be significantly increased from 70° to 80° on the untreated metal surface to over 150°, even reaching 158°. Such a high contact angle means that the oil exhibits a near-spherical shape on this surface, making it extremely difficult to spread and adhere. When the lubricating oil flows in the spiral oil guide groove 501, the superoleophobic coating can significantly reduce the flow resistance between the oil and the groove wall, allowing the oil to flow more smoothly and quickly along the prescribed path of the guide groove, reducing energy loss and turbulence caused by viscous resistance. Simultaneously, in the centrifugal separation chamber 6, the superoleophobic coating effectively prevents the separated oil droplets from re-adhering to the wall surface, prompting them to collect more quickly under gravity at the second outlet 602 and flow back to the oil storage chamber 8. This self-cleaning property ensures that the centrifugal separation chamber 6 maintains high separation efficiency even after long-term operation, avoiding performance degradation due to oil accumulation.

[0045] Example 3 This embodiment, based on Embodiment 1 or Embodiment 2 above, introduces an intelligent temperature control and adaptive adjustment system to further improve the adaptability and operational stability of the device under different operating conditions. For example... Figure 1 As shown, the system mainly includes: a temperature sensor array 10, a PLC controller 11, a piezoelectric actuator 12, and a variable throttle valve 13.

[0046] During the operation of the thrust bearing 4, the temperature of the lubricating oil film is an extremely critical parameter. Excessive temperature leads to decreased oil viscosity, a thinner oil film, reduced load-bearing capacity, and may even cause oil oxidation and deterioration, exacerbating oil slinging and oil mist generation. Conversely, excessively low temperature results in excessively high oil viscosity, increasing frictional losses and churning losses. Therefore, controlling the oil film temperature within the ideal range is crucial for ensuring the long-term stable operation of the thrust bearing 4.

[0047] Therefore, in this embodiment, a temperature sensor array 10 is installed at key locations, such as the inlet of the centrifugal separation chamber 6 and the bearing shell surface of the thrust bearing 4. This array can consist of 6 to 8 high-precision PT100 platinum resistance temperature sensors, uniformly arranged in a ring array on the surface of the bearing mirror plate 5 or within the thrust bearing substrate. The PT100 sensor has a measurement accuracy of ±0.1℃, enabling it to sensitively detect minute temperature changes. Its sampling frequency can be set to 50 Hz, sufficient to reflect the dynamic temperature response of the bearing under rapid load changes in real time. The spacing between two adjacent temperature sensors can be 150 mm to 200 mm, forming a complete temperature distribution monitoring network.

[0048] All temperature sensors are electrically connected to the PLC controller 11, transmitting real-time oil temperature data to the PLC controller 11 as a current signal of, for example, 4-20 mA. The PLC controller 11 is the brain of the entire intelligent temperature control system, with advanced control algorithms pre-installed. This algorithm is based on improved proportional-integral-derivative (PID) control, but compared to traditional PID, it integrates a crucial temperature change rate prediction module. This prediction module does not simply react to the current temperature deviation, but instead uses historical temperature data (e.g., temperature records from the past few seconds to tens of seconds) to build a time series model (e.g., an autoregressive integral moving average model, ARIMA). By analyzing the rate and acceleration of temperature change, this module can predict the temperature change trend over a future period (e.g., the next 30 seconds), achieving predictive control rather than reactive control. This forward-looking predictive function allows the temperature control system to take adjustment measures before temperature anomalies fully occur, thereby keeping temperature fluctuations within a very small range. The response time of the PLC controller 11 is typically less than 100 milliseconds, ensuring rapid response to changes in operating conditions.

[0049] Based on the calculation results of the control algorithm, the PLC controller 11 generates corresponding control signals. These signals are typically pulse width modulation (PWM) signals, and their modulation frequency can be set between 1 kHz and 5 kHz. By changing the duty cycle (0-100%) of the output signal, the amplitude of the subsequent actuator's movement can be precisely controlled.

[0050] The PWM control signal is sent to the piezoelectric actuator 12, which is electrically connected to the PLC controller 11. The piezoelectric actuator 12 is a precision displacement drive device based on the inverse piezoelectric effect. When a voltage is applied, the piezoelectric ceramic crystal inside deforms, thereby generating high-precision, high-speed mechanical displacement. In this embodiment, the response time of the piezoelectric actuator 12 is less than 20 milliseconds (ms), far superior to traditional solenoid valves or stepper motors, and its displacement accuracy can reach ±0.001 millimeters (mm). It exhibits an excellent linear relationship between the applied voltage and the output displacement, with a linearity error of less than 1%, ensuring precise control.

[0051] The piezoelectric actuator 12 is mechanically connected to a variable throttle valve 13 located on a pipeline between the oil reservoir 8 and an external oil source (or cooling system). Specifically, the output end of the piezoelectric actuator 12 is connected to the valve core of the variable throttle valve 13 via a rigid connecting rod. This connecting rod is preferably made of Invar alloy or other materials with a low coefficient of thermal expansion (below 1.5 × 10⁻⁶). -6The material is manufactured to a temperature range of / ℃ to ensure dimensional stability of the connection under different temperature environments, thereby guaranteeing the accuracy of displacement transmission. The opening adjustment range of the variable throttle valve 13 is typically 0 to 1 mm, and its valve core adopts a conical design with a cone angle range of 30° to 45° to achieve fine and linear regulation of oil flow. The piezoelectric actuator 12 directly pushes the valve core of the variable throttle valve 13 according to the mechanical displacement generated by the control signal of the PLC controller 11, thereby changing the valve opening and realizing real-time and precise regulation of the flow rate of cooling lubricating oil flowing into the oil storage chamber 8 (which in turn affects the supply to the spiral guide oil groove 501).

[0052] Below, based on all the above embodiments, the complete working process and principle of the pumped storage thrust bearing anti-oil-slinging device and method of the present invention will be described in detail.

[0053] like Figure 3 As shown, when the unit starts, the rotor shaft 2 drives the thrust head 3 and the mirror plate 5 to rotate at high speed. The lubricating oil in the oil storage chamber 8 is pumped to the spiral oil guide groove 501 on the surface of the mirror plate 5 through the oil supply channel 9. The spiral oil guide groove 501, with its precise spiral angle of 28°-32°, forces the oil to flow stably and directionally from the inner edge of the mirror plate 5 to the outer edge or along a specific direction. The centripetal force component generated by this active guidance effectively counteracts the centrifugal force, initially suppressing the tendency of the oil to be thrown radially out. Under the guidance of the spiral oil guide groove 501, the oil mixed with tiny oil mist enters the centrifugal separation chamber 6. In the annular chamber, the mixed fluid is forced to rotate at high speed, and the dense liquid oil droplets are thrown towards the outer wall of the chamber under the action of strong centrifugal force (which can reach hundreds of times the acceleration of gravity). These accumulated oils flow directly back to the oil storage chamber 8 through the second outlet 602. The three-tiered stepped inner wall of the centrifugal separation chamber 6 further prolongs the residence time of the fluid, enhancing the separation effect and achieving primary separation of oil and oil mist. After centrifugal separation, the gas still containing a small amount of residual oil mist enters the negative pressure reflux channel 7 from the first outlet 601. Because the channel maintains a vacuum of not less than 0.05 MPa, a strong negative pressure suction effect is formed, actively and efficiently capturing these residual oil mists. The guide vanes installed at specific angles (15°-25°) on the inner wall of the channel generate local vortices, increasing the probability of collision between the oil mist and the wall surface, causing the oil mist to condense into oil droplets. Under negative pressure, the captured oil mist (and the condensed oil droplets) are sent into the oil storage chamber 8 through a smooth (Ra≤0.1μm) guide pipe. Inside the oil storage chamber 8, the oil from the centrifugal separation chamber 6 and the oil mist / droplets from the negative pressure reflux channel 7 are mixed, cooled, and defoamed. Subsequently, the recovered lubricating oil is transported again to the spiral oil guide groove 501 through the oil supply channel 9, forming a complete closed-loop cycle, realizing zero discharge of lubricating oil and recycling of resources.

[0054] like Figure 4As shown, during device operation, the temperature sensor array 10, located at key positions (such as the inlet of centrifugal separation chamber 6), collects bearing oil temperature data in real time at a high sampling frequency of 50Hz, and feeds it back to the PLC controller 11 in real time and at high speed via signal lines. Upon receiving the temperature data, the PLC controller 11 immediately activates its internal temperature change rate prediction module. This module combines the current temperature value with historical temperature data, analyzes using a time series model, accurately calculates the current temperature change rate, and predicts the temperature change trend in the near future. The core control algorithm (improved PID) of the PLC controller 11 uses the current temperature, temperature change rate, and predicted future temperature deviation as inputs for comprehensive calculation. By dynamically adjusting the weights of the three PID parameters (proportional, integral, and derivative), the algorithm calculates the optimal control quantity and generates a high-frequency (1-5kHz) PWM control signal with a corresponding duty cycle. Upon receiving the PWM signal, the piezoelectric actuator 12 converts it into a high-precision (±0.001mm) mechanical displacement within an ultra-short time of 20ms. This displacement directly drives the valve core of the variable throttle valve 13, achieving precise and rapid adjustment of the cooling oil flow rate. For example, when it is predicted that the oil temperature will rise, the valve opening is increased to increase the cooling oil flow; conversely, the valve opening is decreased.

[0055] Through the aforementioned millisecond-level rapid closed-loop control, the intelligent temperature control system of this invention can precisely control the oil film temperature fluctuation of the thrust bearing 4 within an extremely narrow range of ±2℃, representing a qualitative leap compared to traditional technologies (where temperature fluctuations often reach 8-15℃). This highly stable thermal state not only directly suppresses the increase in oil mist generation caused by drastic temperature fluctuations but also ensures that the viscosity of the lubricating oil remains within its optimal operating range, guaranteeing the stability of the oil film and further improving the anti-oil-slinging effect and the operational reliability of the bearing.

[0056] In summary, the present invention provides a pumped-storage thrust bearing oil-slinging prevention device and method. By creatively integrating a three-stage physical oil-slinging prevention mechanism—active spiral flow guidance, multi-stage centrifugal force separation, and enhanced vacuum negative pressure capture—and further introducing an intelligent temperature control system based on a temperature prediction model and piezoelectric precision drive, it achieves comprehensive, proactive, and precise control of oil flow behavior from macroscopic to microscopic levels, and from steady-state to transient states. This device and method fundamentally solve the long-standing industry problem of oil slinging and leakage in thrust bearings. Its significant beneficial effects include: oil mist leakage reduced by more than 80%, maintenance intervals more than doubled, significantly reduced operating energy consumption (friction loss reduced by 80%), and excellent adaptability to complex operating conditions (temperature fluctuations controlled within ±2℃). Therefore, this invention provides a revolutionary and highly practical complete technical solution with promising industrial applications for bearing lubrication and sealing in pumped-storage units and even all large-scale high-speed rotating machinery.

[0057] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to cover all possible implementations. Those skilled in the art will recognize that various variations and modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations and modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A device for preventing oil slinging from a pumped-storage thrust bearing, characterized in that, include: Base (1); The rotor shaft (2) is rotatably mounted on the base (1) about its own axis; The thrust head (3) is sleeved on the rotor shaft (2) and is used to bear and transmit axial loads; A thrust bearing (4) is mounted on the base (1) and sleeved on the rotor shaft (2); A mirror plate (5) is disposed on the side of the thrust head (3) facing the thrust bearing (4), and a spiral oil guide groove (501) is integrally formed on the side of the mirror plate (5) facing the thrust bearing (4). Centrifugal separation chamber (6) is located downstream of and connected to the spiral oil guide groove (501). The centrifugal separation chamber (6) has a first outlet (601) and a second outlet (602). The centrifugal separation chamber (6) has an annular structure and uses the principle of centrifugal force to separate the oil and oil mist transported from the spiral oil guide groove (501). The negative pressure reflux channel (7) is located downstream of the centrifugal separation chamber (6) and is connected to the first outlet (601). The negative pressure reflux channel (7) is arranged around the periphery of the centrifugal separation chamber (6) in the circumferential direction. The outlet of the negative pressure return channel (7) is connected to the oil storage chamber (8), and the oil mist flows back to the oil storage chamber (8) through the negative pressure return channel (7). The second outlet (602) of the centrifugal separation chamber (6) is connected to the oil storage chamber (8), and the oil flows back to the oil storage chamber (8) through the centrifugal separation chamber (6). The oil storage chamber (8) is connected to the spiral oil guide groove (501). After the oil mist and oil are mixed and cooled in the oil storage chamber (8), they are transported back to the spiral oil guide groove (501) to cool the thrust head (3).

2. The anti-oil-slinging device for pumped storage thrust bearings according to claim 1, characterized in that, The spiral angle range of the spiral oil guide groove (501) is 28°-32°; And / or, the ratio of the channel depth to the width of the spiral oil guide groove (501) is set to 1:

2.

3. The anti-oil-slinging device for pumped storage thrust bearings according to claim 1, characterized in that, The internal diameter-to-depth ratio of the centrifugal separation chamber (6) is designed to be 1:1.5; And / or, the inner wall of the centrifugal separation chamber (6) adopts a three-level stepped design, with each level being 1 / 3 of the total depth, to form a continuous multi-level deceleration buffer zone.

4. The anti-oil-slinging device for pumped storage thrust bearings according to claim 1, characterized in that, The negative pressure reflux channel (7) maintains a vacuum of ≥0.05MPa. And / or, the inner wall of the negative pressure return channel (7) is provided with a number of guide vanes evenly distributed along the circumference, and the installation angle range of the guide vanes is 15°-25°.

5. The anti-oil-slinging device for pumped storage thrust bearings according to claim 1, characterized in that, It also includes a guide pipe, through which the negative pressure return channel (7) is connected to the oil storage chamber (8); The inner diameter of the guide pipe is in the range of 20-30mm, and the inner surface roughness Ra of the guide pipe is ≤0.1μm.

6. The anti-oil-slinging device for pumped storage thrust bearings according to claim 1, characterized in that, The inner wall surfaces of the spiral oil guide groove (501) and the centrifugal separation chamber (6) are both laser microtextured to form a regular micro-pit array structure, so that when the oil passes through the micro-pit array structure, a micro-oil film can be generated on the microtextured surface. And / or, the inner wall surfaces of the spiral oil guide groove (501) and the centrifugal separation chamber (6) are provided with a super oleophobic coating.

7. The anti-oil-slinging device for pumped storage thrust bearings according to any one of claims 1-6, characterized in that, Also includes: A temperature sensor array (10) is set at the entrance of the centrifugal separation chamber (6) to acquire the oil temperature data entering the centrifugal separation chamber (6) in real time; The PLC controller (11) is electrically connected to the temperature sensor array (10) and is used to generate corresponding control signals based on the oil temperature data fed back by the temperature sensor array (10). The piezoelectric actuator (12) is electrically connected to the PLC controller (11) and is used to convert the control signals sent by the PLC controller (11) into mechanical displacement. A variable throttle valve (13) is installed on the pipeline between the oil storage chamber (8) and the external oil source. The variable throttle valve (13) is connected to the piezoelectric actuator (12) and is controlled by the piezoelectric actuator (12) to regulate the oil flow.

8. The anti-oil-slinging device for pumped storage thrust bearings according to claim 7, characterized in that, The control algorithm of the PLC controller (11) includes a temperature change rate prediction module. The temperature change rate prediction module establishes a time series model through historical temperature data to predict temperature trends in advance and adjust the control signal.

9. A method for preventing oil slinging from a pumped storage thrust bearing, characterized in that, The method includes the anti-oil-slinging device for the pumped storage thrust bearing (4) as described in any one of claims 1-8; the method includes the following steps: The spiral oil guide groove (501) guides the oil to form a directional flow, initially suppressing the tendency of centrifugal oil slinging; The pre-guided oil enters the centrifugal separation chamber (6), and the oil and oil mist are separated by the principle of centrifugal force. The residual oil mist in the centrifugal separation chamber (6) is captured under vacuum conditions through the negative pressure reflux channel (7); The captured oil mist is guided back to the oil storage chamber (8).

10. The method for preventing oil slinging from a pumped storage thrust bearing according to claim 9, characterized in that, It also includes the following steps: The temperature sensor array (10) is used to acquire the oil temperature data for cooling in real time and feed it back to the PLC controller (11). The PLC controller (11) is used to analyze the oil temperature data and output control signals; The opening of the variable throttle valve (13) is adjusted by the piezoelectric actuator (12) according to the control signal output by the PLC controller (11) so that the oil film temperature fluctuation is controlled within ±2℃.

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