Optimization method for operation of main engine lubricating oil cooler after shutdown of thermal power plant unit

Abstract

The invention provides a method for optimizing operation of a main engine lubricating oil cooler after shutdown of a thermal power plant unit, and relates to the technical field of machine overhaul, which comprises the following steps of: 1, additionally arranging a connecting pipeline between a main engine lubricating oil cooler A and a main engine lubricating oil cooler B, two flexible branch pipes are arranged on the connecting pipeline and are respectively connected to an inlet electric valve of the main engine lubricating oil cooler A and an inlet electric valve of the main engine lubricating oil cooler B; step 2, valve arrangement; and step 3, operation: cooling water of a main engine lubricating oil cooler is supplied from industrial water to industrial water flowing through a heat supply circulating water emergency water supplementing manual valve, the industrial water replaces circulating water, energy consumption of a circulating water pump can be reduced, operation of a circulating water system does not need to be maintained after shutdown, and energy consumption is reduced. Meanwhile, the cooling requirement of the oil cooler is guaranteed through stable supply of industrial water, if an industrial water system is in a running state, the industrial water system can be directly used for cooling, and the additional starting cost of a circulating water pump is avoided.

Description

Technical Field

[0001] This invention relates to the field of machine maintenance technology, and in particular to an optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit is shut down. Background Technology

[0002] After a thermal power plant unit is shut down, the main engine lubrication system still needs to continue operating, which will inevitably generate heat and cause the main engine lubrication oil temperature to rise. In order to ensure the safe and stable operation of the main engine lubrication system, the main engine lubrication oil temperature needs to be kept within a reasonable range.

[0003] The current practice is to briefly start the circulating water pump to run the circulating water system and lower the temperature of the main unit's lubricating oil. However, since the circulating water pump is a high-voltage device, frequent starts can easily lead to energy waste, damage the circulating water pump, and affect the maintenance of the circulating water system.

[0004] Therefore, it is necessary to provide a new optimized method for the operation of the main engine lubricating oil cooler after the shutdown of a thermal power plant unit to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an optimized method for the operation of the main unit lubricating oil cooler after a thermal power plant unit is shut down.

[0006] The optimized operation method for the main engine lubricating oil cooler after a thermal power plant unit shutdown, provided by this invention, includes the following steps:

[0007] Step 1: Piping layout. A connecting pipe is installed between the main engine lubricating oil cooler A and the main engine lubricating oil cooler B. The connecting pipe is equipped with two flexible branch pipes, which are respectively connected to the inlet electric valve of the main engine lubricating oil cooler A and the inlet electric valve of the main engine lubricating oil cooler B.

[0008] Step 2, valve arrangement: Install an emergency water supply manual valve for industrial water to heating circulating water at the inlet of the connecting pipe; install a manual valve and a check valve for industrial water to the inlet pipe of the main engine lubricating oil cooler in the middle of the connecting pipe; and install a manual valve for industrial water to the main engine lubricating oil cooler A and a manual valve for industrial water to the main engine lubricating oil cooler B on the two flexible branch pipes respectively.

[0009] Step 3: Monitoring Operation. Data acquisition devices are added to both the main engine lubricating oil cooler A and main engine lubricating oil cooler B to acquire their real-time operating data and extract relevant features. Multiple decision trees are constructed based on historical operating data. Each tree is trained using features and samples from a random operating dataset. The voting mechanism of the random forest algorithm is then used to determine the final classification. Real-time data is substituted into the decision trees to predict the situation in the future. After the generator unit shuts down, the manual valves on the industrial water inlet pipes to the main engine lubricating oil cooler, the industrial water inlet valves to main engine lubricating oil cooler A and B are opened, while the electric inlet valves to main engine lubricating oil cooler A and B are closed. The cooling water for the main engine lubricating oil coolers is supplied by industrial water flowing through the emergency replenishment valve for the heating circulating water. The industrial water supply is adjusted according to the prediction results.

[0010] In a further method, if the oil temperature of the main engine lubricating oil cooler A or the main engine lubricating oil cooler B approaches the upper limit during operation, the flow rate of industrial water is adjusted by manually adjusting the emergency water supply valve from industrial water to heating circulating water.

[0011] In a further step, the manual valves for emergency water replenishment from industrial water to heating circulating water, industrial water to the inlet pipe of the main engine lubricating oil cooler, check valve, manual valve for entering the main engine lubricating oil cooler A, and manual valve for entering the main engine lubricating oil cooler B are all equipped with polytetrafluoroethylene gaskets at the pipe flange connections.

[0012] A further method involves installing a pressure gauge downstream of the check valve to monitor industrial water pressure fluctuations in real time and periodically check the opening and closing performance of the check valve to prevent cooling water backflow due to jamming.

[0013] In a further method, the connecting pipes are arranged overhead.

[0014] In a further step, the main engine lubricating oil cooler A and the main engine lubricating oil cooler B are respectively equipped with an electric valve for industrial water to exit the main engine lubricating oil cooler A and an electric valve for industrial water to exit the main engine lubricating oil cooler B.

[0015] Compared with related technologies, the optimized method for the operation of the main engine lubricating oil cooler after the shutdown of a thermal power plant unit provided by this invention has the following beneficial effects:

[0016] 1. This invention reduces the energy consumption of the circulating water pump by replacing the circulating water with industrial water. After shutdown, there is no need to maintain the operation of the circulating water system. At the same time, the stable supply of industrial water ensures the cooling needs of the oil cooler. If the industrial water system is already in operation, it can be used directly for cooling, avoiding the additional start-up cost of the circulating water pump.

[0017] 2. The manual valve on the flexible branch pipe of this invention can realize independent control of the main engine lubricating oil cooler A or the main engine lubricating oil cooler B, which facilitates maintenance or fault isolation. For example, when one side of the oil cooler is under maintenance, the other side can still operate. By flexibly switching the cooling water source and isolation function, the operating efficiency and safety of the oil cooler after shutdown are improved. The use of flexible branch pipe can better adapt to the vibration and deformation of the equipment and reduce the risk of leakage caused by pipe stress.

[0018] 3. This invention adds data acquisition equipment to the main engine lubricating oil cooler A and the main engine lubricating oil cooler B to acquire their operating data in real time. The operating data is then analyzed and predicted in real time. After the generator set stops, the industrial water supply is adjusted according to the prediction results. Based on the prediction results, maintenance plans are arranged in advance to avoid downtime losses caused by equipment failure. The structure is simple, reduces the frequency of overflow pipe blockage, significantly reduces maintenance costs, and minimizes environmental hazards. Attached Figure Description

[0019] The accompanying drawings are provided to further understand this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof.

[0020] Figure 1 A schematic diagram illustrating the operation of the optimized method for the operation of the main engine lubricating oil cooler after the shutdown of a thermal power plant unit, provided by the present invention.

[0021] Figure 2 The flowchart is a flowchart of the optimized method for the operation of the main engine lubricating oil cooler after the shutdown of a thermal power plant unit, provided by the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this application, unless otherwise stated, "multiple" means two or more.

[0024] Example 1

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0026] To gain a more detailed understanding of the features and technical content of the embodiments disclosed herein, the following description is provided in conjunction with the accompanying drawings. Figure 1 as well as Figure 2 ,in, Figure 1 A schematic diagram illustrating the operation of the optimized method for the operation of the main engine lubricating oil cooler after the shutdown of a thermal power plant unit, provided by the present invention. Figure 2 This flowchart illustrates the optimized operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as provided by the present invention. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the embodiments disclosed. In the following description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments.

[0027] However, one or more embodiments can still be implemented without these details. In other cases, well-known structures and devices may be shown in a simplified manner to simplify the drawings.

[0028] In the specific implementation process, such as Figures 1-2 As shown, the optimized operation method for the main engine lubricating oil cooler after a thermal power plant unit shutdown includes the following steps:

[0029] Step 1: Piping layout. A connecting pipe is installed between the main engine lubricating oil cooler A and the main engine lubricating oil cooler B. The connecting pipe is installed overhead and has two flexible branch pipes that are respectively connected to the inlet electric valve of the main engine lubricating oil cooler A and the inlet electric valve of the main engine lubricating oil cooler B. The main engine lubricating oil cooler A and the main engine lubricating oil cooler B are also equipped with electric valves for industrial water to the outlet of the main engine lubricating oil cooler A and the outlet of the main engine lubricating oil cooler B, respectively.

[0030] Step 2, valve arrangement: Install an emergency water supply manual valve for industrial water to heating circulating water at the inlet of the connecting pipe; install a manual valve and a check valve for industrial water to the inlet pipe of the main engine lubricating oil cooler in the middle of the connecting pipe; and install a manual valve for industrial water to the main engine lubricating oil cooler A and a manual valve for industrial water to the main engine lubricating oil cooler B on the two flexible branch pipes respectively.

[0031] Step 3: Monitoring Operation. Data acquisition devices are added to both the main engine lubricating oil cooler A and main engine lubricating oil cooler B to acquire their real-time operating data and extract relevant features. Multiple decision trees are constructed based on historical operating data. Each tree is trained using features and samples from a random operating dataset. The voting mechanism of the random forest algorithm is then used to determine the final classification. Real-time data is substituted into the decision trees to predict the situation in the future. After the generator unit shuts down, the manual valves on the industrial water inlet pipes to the main engine lubricating oil cooler, the industrial water inlet valves to main engine lubricating oil cooler A and B are opened, while the electric inlet valves to main engine lubricating oil cooler A and B are closed. The cooling water for the main engine lubricating oil coolers is supplied by industrial water flowing through the emergency replenishment valve for the heating circulating water. The industrial water supply is adjusted according to the prediction results.

[0032] It is worth noting that the installed data acquisition equipment includes temperature sensors, pressure sensors, and flow sensors, which are used to acquire real-time operating data of oil temperature, water temperature, pressure, and flow. The analysis and prediction of the operating data of the main engine lubricating oil cooler A and the main engine lubricating oil cooler B includes extracting features from the preprocessed data, such as the rate of change of oil temperature, the range of water temperature fluctuation, and pressure stability. Multiple decision trees are constructed based on historical operating data. Each tree is trained based on the features and samples of the random operating dataset. The voting mechanism of the random forest algorithm is then used to determine the final classification. Real-time data is substituted into the decision trees to predict the situation in the future. After the generator set is shut down, the trained model is used to make real-time predictions of the operating data of the main engine lubricating oil cooler A and the main engine lubricating oil cooler B to obtain future parameters such as oil temperature and water temperature. Based on the prediction results, the supply of industrial water is adjusted by manually adjusting the emergency water supply valve from industrial water to heating circulating water to ensure the best cooling effect of the oil cooler and avoid energy waste.

[0033] Specifically, the data acquisition equipment collects the oil temperature T0(t) and water temperature T... w (t), oil pressure P0(t), water pressure P w The sampling frequency for the operation data of Q(t) and flow rate Q(t) is 1 minute;

[0034] Preprocessing of the operational data includes using moving average filtering to eliminate sensor noise and normalization.

[0035] For feature extraction, it is necessary to extract the rate of change of oil temperature, the range of water temperature fluctuation, and pressure stability;

[0036] Calculation of oil temperature change rate:

[0037] Calculation of water temperature fluctuation range: ΔT w (t)=T w (t)-T w (t-Δt);

[0038] Pressure stability calculation:

[0039] It should be noted that the modeling and prediction are based on an autoregressive moving average difference model:

[0040] Assuming the oil temperature sequence T0(t) is a non-stationary sequence, and t is a time series at time t, it needs to be differencingd d times to make it stationary. Its model form is as follows: φ(B)(1-B) d T0(t) = θ(B)∈(t), where B is the shift operator (BT0(t) = T0(t-1)), φ(B) = 1 - φ(B) - ... - φ p B p For the natural regression coefficient, θ(B) = 1 + θ(B) - ... - θ q B q Let (1-B) be the moving average coefficient. d Here, ∈(t) is the difference operator, p is the order of the autoregressive term, and q is the order of the moving average term.

[0041] The predicted future oil temperature τ is as follows:

[0042] Input features for the Random Forest algorithm:

[0043] The classification objective is as follows: for states S∈{0,1}, when S=1, no adjustment of industrial water flow is required, and when S=0, industrial water flow needs to be adjusted.

[0044] Training process: N decision trees are generated by randomly sampling from historical data, each tree is based on a subset of features. Training, outputting classification result S i ∈{0,1}, the voting mechanism is as follows:

[0045]

[0046] It is understandable that industrial water temperature is usually higher than circulating water (especially in summer), which may lead to a decrease in the cooling capacity of the oil cooler. It is necessary to ensure that the lubricating oil outlet temperature is still below the safe threshold (e.g., ≤45℃). If the oil temperature approaches the upper limit during the operation of the main unit lubricating oil cooler A or the main unit lubricating oil cooler B, the industrial water flow rate can be adjusted by manually adjusting the emergency water supply valve from industrial water to heating circulating water. Replacing circulating water with industrial water can reduce the energy consumption of the circulating water pump. After shutdown, there is no need to maintain the operation of the circulating water system. At the same time, the stable supply of industrial water can ensure the cooling needs of the oil cooler. If the industrial water system is already in operation, it can be used directly for cooling, avoiding the additional start-up costs of the circulating water pump.

[0047] In some embodiments, since the addition of pipelines may lead to leakage risks, polytetrafluoroethylene (PTFE) gaskets are installed at the connection points between the manual valves for emergency water replenishment from industrial water to heating circulating water, the manual valves for the inlet pipeline from industrial water to the main engine lubricating oil cooler, the check valve, the manual valve for the inlet of industrial water to the main engine lubricating oil cooler A, and the manual valve for the inlet of industrial water to the main engine lubricating oil cooler B, and the pipeline flanges. These gaskets replace traditional copper sheet seals, improve sealing reliability, and can be subjected to a water pressure test (0.5 MPa) before installation to ensure pipeline sealing.

[0048] In some embodiments, the check valve can prevent industrial water from flowing back into the heating circulating water system, but its sensitivity must be ensured, and the opening and closing performance of the check valve should be checked regularly to avoid cooling water backflow due to jamming. A pressure gauge is also installed after the check valve to monitor industrial water pressure fluctuations in real time.

[0049] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of the invention is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0050] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0051] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0052] In the embodiments provided in this application, it should be understood that the disclosed systems, modules, and methods can be implemented in other ways. For example, the module embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between modules or units, and may be electrical, mechanical, or other forms.

[0053] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. This application is not limited to the exact structures described above and illustrated in the accompanying drawings, and it should not be considered that the specific implementation of this application is limited to these descriptions. For those skilled in the art, various changes and modifications made without departing from the concept of this application should be considered to fall within the protection scope of this application.

Claims

1. An optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, characterized in that, Includes the following steps: Step 1: Piping layout. A connecting pipe is installed between the main engine lubricating oil cooler A and the main engine lubricating oil cooler B. The connecting pipe is equipped with two flexible branch pipes, which are respectively connected to the inlet electric valve of the main engine lubricating oil cooler A and the inlet electric valve of the main engine lubricating oil cooler B. Step 2, valve arrangement: Install an emergency water supply manual valve for industrial water to heating circulating water at the inlet of the connecting pipe; install a manual valve and a check valve for industrial water to the inlet pipe of the main engine lubricating oil cooler in the middle of the connecting pipe; and install a manual valve for industrial water to the main engine lubricating oil cooler A and a manual valve for industrial water to the main engine lubricating oil cooler B on the two flexible branch pipes respectively. Step 3: Monitoring Operation. Data acquisition devices are added to both the main engine lubricating oil cooler A and main engine lubricating oil cooler B to acquire their real-time operating data and extract relevant features. Multiple decision trees are constructed based on historical operating data. Each tree is trained using features and samples from a random operating dataset. The voting mechanism of the random forest algorithm is then used to determine the final classification. Real-time data is substituted into the decision trees to predict the situation in the future. After the generator unit shuts down, the manual valves on the industrial water inlet pipes to the main engine lubricating oil cooler, the industrial water inlet valves to main engine lubricating oil cooler A and B are opened, while the electric inlet valves to main engine lubricating oil cooler A and B are closed. The cooling water for the main engine lubricating oil coolers is supplied by industrial water flowing through the emergency replenishment valve for the heating circulating water. The industrial water supply is adjusted according to the prediction results.

2. The optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as described in claim 1, is characterized in that... During the operation of step three, ensure that the outlet temperature of the main engine lubricating oil cooler A and the main engine lubricating oil cooler B remains below the safety threshold. If the oil temperature of the main engine lubricating oil cooler A or the main engine lubricating oil cooler B approaches the upper limit during operation, adjust the industrial water flow rate through the emergency water replenishment valve from industrial water to heating circulating water.

3. The optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as described in claim 2, is characterized in that... The manual valves for emergency water replenishment from industrial water to heating circulating water, industrial water to the inlet pipe of the main engine lubricating oil cooler, check valve, manual valve for entering the main engine lubricating oil cooler A, and manual valve for entering the main engine lubricating oil cooler B are all equipped with polytetrafluoroethylene gaskets at the pipe flange connections.

4. The optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as described in claim 3, is characterized in that... A pressure gauge is also installed downstream of the check valve to monitor industrial water pressure fluctuations in real time.

5. The optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as described in claim 4, is characterized in that... The connecting pipes are arranged overhead.

6. The optimized method for the operation of the main engine lubricating oil cooler after a thermal power plant unit shutdown, as described in claim 5, is characterized in that... The main engine lubricating oil cooler A and the main engine lubricating oil cooler B are respectively equipped with an electric valve for industrial water to exit from the main engine lubricating oil cooler A and an electric valve for industrial water to exit from the main engine lubricating oil cooler B.

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