Low-pressure cylinder through-flow blade self-cleaning device

Abstract

The utility model discloses a kind of low-pressure cylinder through-flow blade self-cleaning device, including cylinder and the through-flow blade being set to the inside of cylinder, the position of the cylinder outer wall corresponding through-flow blade Annular distribution has ultrasonic transducer, the cylinder inner wall of the other side of through-flow blade is fixed with distribution pipe by U-shaped frame one, beam hanger is set between U-shaped frame one, and vibration sensor and temperature sensor are arranged on the beam hanger, and the outside of the cylinder is provided with the mixed flow pipe connected with distribution pipe, the top of mixed flow pipe is parallelly arranged with airflow pipe and liquid flow pipe. The utility model generates flexible jet by low-pressure gas-liquid mixture, effectively removes dirt and deposit on the surface of through-flow blade, significantly improves cleaning efficiency, the ultrasonic transducer of the cylinder outer wall corresponding through-flow blade position Annular distribution, the adhesion of scale layer is destroyed by low-frequency vibration, further enhances cleaning effect.

Description

Technical Field

[0001] This utility model relates to the field of flow vane cleaning, specifically a self-cleaning device for flow vanes in a low-pressure cylinder. Background Technology

[0002] In the steam turbine unit of a thermal power plant, the low-pressure cylinder, as the end-stage working component of the steam cycle, has internal flow-through blades that directly contact the low-pressure steam, making it the core structure for converting thermal energy into mechanical energy. However, during long-term operation, salts, impurities, and scale formed by condensate carried in the steam gradually adhere to the surface of the flow-through blades (especially critical areas such as the steam inlet edge, back arc, and blade tip), resulting in a reduction in the blade flow-through area and an increase in surface roughness.

[0003] This scaling phenomenon directly leads to two major problems: First, the flow efficiency decreases significantly, resulting in increased coal consumption for turbine power generation. According to industry data, for every 0.1mm increase in blade scaling thickness, the unit's thermal efficiency can decrease by 1%-2%, resulting in tens of thousands of yuan in additional energy losses annually. Second, uneven scaling layers can disrupt the dynamic balance of the blades, causing additional vibrations during high-speed rotation (typically 3000 r / min). Long-term operation may lead to blade fatigue damage, or even serious equipment accidents such as blade breakage, threatening the safe and stable operation of the unit.

[0004] To address the scaling problem on flow path blades, existing technologies mainly employ the following four cleaning methods, but all have significant limitations: Manual cleaning by shutting down the cylinder: This method requires disassembling the entire low-pressure cylinder and removing the scale layer by manual scraping and grinding. Although this method allows direct contact with the blades, it requires a shutdown of 2-3 days, which seriously affects the power plant's power generation plan. In addition, manual operation can easily scratch the anti-cavitation coating (such as Stellite alloy coating) on ​​the blade surface, shortening the blade's service life.

[0005] Online high-pressure water jet cleaning: This method uses a high-pressure water pump (pressure typically ≥10MPa) to spray high-pressure water onto the blades through a pre-reserved interface in the cylinder. While this method does not require shutdown, the high-pressure water jet can easily impact the metal substrate of the blades, causing blade edge deformation. Additionally, water residue inside the cylinder may cause short circuits in internal electrical components or corrosion of internal parts.

[0006] Single ultrasonic vibration cleaning: An ultrasonic transducer is installed on the outer wall of the cylinder to break the adhesion of the scale layer through vibration. Although this method does not cause mechanical damage, it is difficult to remove stubborn heavy scale (such as crystalline salt scale) by relying solely on vibration, and the cleaning effect cannot be judged, which can easily lead to over-cleaning or incomplete cleaning.

[0007] Regular offline chemical cleaning: Chemical descaling agents are injected into the cylinder to dissolve the scale layer through a chemical reaction. This method carries the risk of chemical corrosion of the blade substrate, and requires multiple rinsings after cleaning to remove residual chemicals. The operation process is complex and environmental treatment costs are high.

[0008] Therefore, the industry urgently needs a low-pressure cylinder flow vane cleaning device that requires no shutdown, causes no mechanical damage, can monitor the scaling status in real time, and has high cleaning efficiency. This would solve the core pain points of existing technologies, such as large downtime losses, high risk of cleaning damage, and inaccurate monitoring, and ensure the long-term, efficient, and safe operation of steam turbine units. Utility Model Content

[0009] The purpose of this invention is to provide a self-cleaning device for the flow vanes of a low-pressure cylinder to solve the problems mentioned in the background art.

[0010] To achieve the above objectives, a self-cleaning device for a low-pressure cylinder flow vane is provided, comprising a cylinder body and flow vanes disposed inside the cylinder body. Ultrasonic transducers are distributed in a ring on the outer wall of the cylinder body corresponding to the position of the flow vanes. A manifold is fixed to the inner wall of the cylinder body on one side of the flow vanes by a U-shaped frame, and a negative pressure pipe connected to the manifold is provided on the outer wall of the cylinder body. A distribution pipe is fixed to the inner wall of the cylinder on the other side of the flow vane by a U-shaped frame. A suspension beam is provided between the U-shaped frames, and a vibration sensor and a temperature sensor are arranged side by side on the suspension beam. Nozzle 1, nozzle 2 and nozzle 3 are arranged in a fan shape below the inner side of the distribution pipe. A mixing pipe connected to the distribution pipe is provided on the outer side of the cylinder. An airflow pipe and a liquid flow pipe are arranged side by side at the top of the mixing pipe.

[0011] Preferably, both the negative pressure pipe and the manifold are annular structures, and the negative pressure pipe and the manifold are laid along the inner wall of the cylinder.

[0012] Preferably, both the gas flow pipe and the liquid flow pipe are equipped with flow valves, and the flow valves are electromagnetic proportional valves whose opening degree can be adjusted by current signals.

[0013] Preferably, the outer wall of the cylinder is uniformly provided with slots for installing ultrasonic transducers, and the space between the inner wall of the slots and the ultrasonic transducers is filled with thermally conductive silicone grease.

[0014] Preferably, the flow-through blades are connected to the center of the suspension beam via a coupling.

[0015] Preferably, the inner wall of the manifold is uniformly provided with adsorption holes, and the negative pressure pipe is provided with a solenoid valve.

[0016] Preferably, both the vibration sensor and the temperature sensor are fitted with a high-temperature resistant ceramic protective shell on the outside of their detection ends, and the surface of the protective shell has a strip-shaped through hole that is perfectly adapted to the sensor detection ends.

[0017] This utility model provides a self-cleaning device for the flow vanes of a low-pressure cylinder, which has significant advantages and positive effects compared with the prior art, specifically reflected in the following aspects: 1. By using nozzles one, two, and three arranged in a fan shape at the bottom of the distribution pipe, combined with the mixing pipe at the inlet of the airflow and liquid flow pipes, a low-pressure gas-liquid mixture can be formed, generating a flexible jet. This flexible jet can effectively remove dirt and deposits from the surface of the flow vanes, significantly improving cleaning efficiency. The ultrasonic transducers arranged in a ring on the outer wall of the cylinder corresponding to the flow vanes use low-frequency vibration to break down the adhesion of the scale layer, further enhancing the cleaning effect. Ultrasonic vibration can penetrate deep into the scale layer, loosening it and making it easier for the jet to remove.

[0018] 2. The device is equipped with vibration and temperature sensors to monitor the scaling status of the flow blades in real time. Scaling can cause the blades' natural vibration frequency to shift and the surface temperature to rise. Through dual sensor monitoring, the degree of scaling can be accurately determined. Based on the data fed back by the sensors, the device can automatically adjust the cleaning intensity, such as jet pressure and ultrasonic power, to avoid energy waste and equipment damage caused by over-cleaning. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the cross-sectional structure of the present invention; Figure 2 This is a schematic diagram of the internal cross-sectional structure of this utility model; Figure 3 This utility model Figure 1 Enlarged structural diagram at point A in the middle; Figure 4 This is a schematic diagram of the nozzle distribution structure of the distribution tube of this utility model.

[0020] The following are the labels in the diagram: 1. Cylinder block; 2. Suspension beam; 3. Distribution pipe; 4. Flow vane; 5. U-shaped frame one; 6. Ultrasonic transducer; 7. Vibration sensor; 8. Temperature sensor; 9. Coupling; 10. Adsorption hole; 11. Manifold; 12. U-shaped frame two; 13. Solenoid valve; 14. Negative pressure pipe; 15. Groove; 16. Nozzle one; 17. Nozzle two; 18. Nozzle three; 19. Mixing pipe; 20. Flow valve; 21. Airflow pipe; 22. Liquid flow pipe. Detailed Implementation

[0021] Please see Figures 1-4This utility model provides a self-cleaning device for flow vanes of a low-pressure cylinder, including a cylinder body 1 and flow vanes 4 disposed inside the cylinder body 1. Ultrasonic transducers 6 are distributed in a ring on the outer wall of the cylinder body 1 at the positions corresponding to the flow vanes 4. The outer wall of the cylinder body 1 is uniformly provided with slots 15 for installing ultrasonic transducers 6, and thermally conductive silicone grease is filled between the inner wall of the slots 15 and the ultrasonic transducers 6.

[0022] Specifically, such as Figure 1 As shown, the low-pressure cylinder flow vane self-cleaning device in this embodiment includes a cylinder body 1 and flow vanes 4 disposed inside the cylinder body 1. The cylinder body 1 has a cylindrical structure, and its internal space is used to accommodate the flow vanes 4. The flow vanes 4 are evenly distributed along the axial direction of the cylinder body 1 to guide fluid flow.

[0023] On the outer wall of the cylinder 1, ultrasonic transducers 6 are arranged in a ring at the position corresponding to the flow vane 4. The ultrasonic transducers 6 are used to generate high-frequency ultrasonic waves to achieve the cleaning effect on the flow vane 4. Specifically, the ultrasonic transducers 6 can effectively remove dirt and deposits on the surface of the flow vane 4 through their high-frequency vibration, and keep the flow vane 4 clean.

[0024] To install the ultrasonic transducer 6, slots 15 are evenly provided on the outer wall of the cylinder 1. The shape of the slots 15 matches the shape of the ultrasonic transducer 6 to facilitate the embedding and fixing of the ultrasonic transducer 6. Thermal grease is filled between the inner wall of the slots 15 and the ultrasonic transducer 6. The function of the thermal grease is to improve the heat conduction efficiency between the ultrasonic transducer 6 and the cylinder 1, and to ensure that the heat generated by the ultrasonic transducer 6 during operation can be dissipated in time to avoid affecting its normal operation due to overheating.

[0025] A manifold 11 is fixed to the inner wall of the cylinder 1 on one side of the flow vane 4 by a U-shaped bracket 12, and a negative pressure pipe 14 connected to the manifold 11 is provided on the outer wall of the cylinder 1.

[0026] The inner wall of the manifold 11 is uniformly provided with adsorption holes 10, and the negative pressure pipe 14 is provided with a solenoid valve 13.

[0027] Specifically, the manifold 11 is fixed on the inner wall of the cylinder 1 and supported by the U-shaped bracket 12. The manifold 11 is a cylindrical tubular structure with multiple adsorption holes 10 evenly distributed on its inner wall.

[0028] U-shaped bracket 2 12: U-shaped bracket 2 12 is used to fix the manifold 11. One end of it is fixed to the inner wall of the cylinder 1, and the other end is connected to the outer wall of the manifold 11. The material of U-shaped bracket 2 12 is preferably high-strength steel to ensure that it is firmly fixed.

[0029] Negative pressure pipe 14: The negative pressure pipe 14 is installed on the outer wall of the cylinder 1 and connected to the manifold 11. The negative pressure pipe 14 is used to introduce negative pressure to achieve the dust adsorption function. The material of the negative pressure pipe 14 is preferably a pressure-resistant rubber tube to ensure its sealing performance in a negative pressure environment.

[0030] Solenoid valve 13: Solenoid valve 13 is installed on negative pressure pipe 14 and is used to control the opening and closing of negative pressure. The action of solenoid valve 13 is controlled by the control system to ensure precise control of fluid. The material of solenoid valve 13 is preferably a corrosion-resistant alloy to extend its service life.

[0031] A distribution pipe 3 is fixed to the inner wall of the cylinder 1 on the other side of the flow vane 4 by a U-shaped frame 5. The negative pressure pipe 14 and the manifold 11 are both annular structures, and the negative pressure pipe 14 and the manifold 11 are laid along the inner wall of the cylinder 1.

[0032] A suspension beam 2 is provided between the U-shaped frame 5. The flow vane 4 is connected to the center of the suspension beam 2 through the connecting shaft 9. A vibration sensor 7 and a temperature sensor 8 are arranged side by side on the suspension beam 2. The outer side of the detection end of the vibration sensor 7 and the temperature sensor 8 is covered with a high-temperature resistant ceramic protective shell. The surface of the protective shell has a strip-shaped through hole that is completely adapted to the detection end of the sensor.

[0033] Specifically, such as Figure 1 As shown, the core components of this utility model include a cylinder body 1, a flow vane 4, a U-shaped frame 5, a distribution pipe 3, a negative pressure pipe 14, a manifold 11, a suspension beam 2, a connecting shaft 9, a vibration sensor 7, and a temperature sensor 8.

[0034] The U-shaped frame 5 is U-shaped, with its two ends fixed to the inner wall of the cylinder 1, and the middle part used to support the distribution pipe 3. The U-shaped frame 5 is made of high-strength stainless steel to ensure its stability under high temperature and high pressure.

[0035] Distribution pipe 3: Distribution pipe 3 is fixed to the inner wall of cylinder 1 by U-shaped bracket 5. Its main function is to evenly distribute fluid and improve fluid flow efficiency. The material of distribution pipe 3 is a corrosion-resistant alloy to extend its service life.

[0036] Negative pressure pipe 14 and manifold 11: Both negative pressure pipe 14 and manifold 11 are annular structures, laid along the inner wall of cylinder 1. Negative pressure pipe 14 is used to generate negative pressure to attract fluid into cylinder 1; manifold 11 is used to collect the fluid after it has passed through flow vane 4. Both are made of high-temperature resistant and corrosion-resistant materials.

[0037] Cantilever Frame 2: The cantilever frame 2 is located between the U-shaped frame 5, and its main function is to support the flow vanes 4. The material of the cantilever frame 2 is high-strength aluminum alloy, which is both lightweight and sturdy.

[0038] Flow vane 4: Flow vane 4 is connected to the center of the suspension beam 2 via coupling shaft 9. The design of flow vane 4 allows it to rotate as fluid passes through, thereby changing the flow direction and speed of the fluid. The material of flow vane 4 is a high-temperature resistant alloy to ensure its stability in high-temperature environments.

[0039] Coupling 9: Coupling 9 is used to connect the flow vane 4 and the suspension beam 2, ensuring stable transmission between the two. Coupling 9 is made of high-strength steel and its surface is treated with anti-corrosion coating.

[0040] Vibration sensor 7 and temperature sensor 8: Vibration sensor 7 and temperature sensor 8 are arranged side by side on the suspension beam 2. Vibration sensor 7 is used to monitor the vibration of the flow vane 4 in real time, and temperature sensor 8 is used to monitor the temperature changes inside the cylinder block 1. Both sensors are covered with high-temperature resistant ceramic protective shells on their outer edges.

[0041] High-temperature resistant ceramic protective housing: The high-temperature resistant ceramic protective housing is used to protect the detection ends of vibration sensor 7 and temperature sensor 8, preventing them from being damaged in high-temperature environments. The surface of the protective housing has strip-shaped through holes that are perfectly adapted to the sensor detection ends, ensuring that the sensors can accurately detect vibration and temperature data.

[0042] The lower inner side of the distribution pipe 3 is provided with nozzle 16, nozzle 2 17 and nozzle 3 18 arranged in a fan shape, and the outer side of the cylinder body 1 is provided with a mixing pipe 19 connected to the distribution pipe 3. The top of the mixing pipe 19 is provided with an airflow pipe 21 and a liquid flow pipe 22 arranged side by side.

[0043] Both the airflow pipe 21 and the liquid flow pipe 22 are equipped with flow valves 20, and the flow valves 20 are electromagnetic proportional valves whose opening degree can be adjusted by current signals.

[0044] Specifically, nozzles 16, 17, and 18 are all made of corrosion-resistant materials, and their nozzles are designed in a conical shape to facilitate uniform fluid spraying. The three nozzles are arranged in a fan shape, with nozzle 16 located on the left side of the fan, nozzle 27 in the middle, and nozzle 38 on the right side. This distribution ensures uniform fluid distribution within cylinder 1, improving the mixing effect.

[0045] Mixing pipe 19: The mixing pipe 19 is located on the outside of the cylinder body 1 and is connected to the distribution pipe 3. The mixing pipe 19 is made of high-strength plastic or metal and has good sealing performance and pressure resistance. An airflow pipe 21 and a liquid flow pipe 22 are arranged side by side at the top of the mixing pipe 19.

[0046] Gas flow pipe 21 and liquid flow pipe 22: Gas flow pipe 21 and liquid flow pipe 22 are used to transport gas and liquid respectively, and are arranged side by side at the top of the mixing pipe 19. The diameter of gas flow pipe 21 and liquid flow pipe 22 is designed according to actual application requirements to ensure smooth transport of gas and liquid.

[0047] Flow valve 20: Flow valves 20 are installed on both the gas flow pipe 21 and the liquid flow pipe 22. The flow valves 20 are electromagnetic proportional valves, which can adjust their opening degree through current signals, thereby precisely controlling the flow rate of gas and liquid. The selection of electromagnetic proportional valves ensures precise flow regulation and improves the automation level of the device.

[0048] The working principle of this utility model is as follows: When in use, the device control system is activated, and the vibration sensor 7 on the suspension beam 2 begins to collect the vibration frequency data of the flow vane 4 in real time. The temperature sensor 8 simultaneously collects the temperature data of the surface of the flow vane 4 and the inside of the cylinder 1. The system compares the collected vibration frequency and temperature data with the preset scale-free state benchmark value. If the vibration frequency is 5%-10% lower than the benchmark value and the temperature is 3-5℃ higher than the benchmark value, it is determined that the flow vane 4 has moderate or higher scale, and the cleaning program is triggered.

[0049] After the cleaning program is started, the ultrasonic transducers 6 distributed in a ring on the outer wall of the cylinder 1 are activated first. The ultrasonic transducers 6 transmit high-frequency vibrations into the cylinder 1 through the slot 15. The vibration energy is conducted to the flow vanes 4 through the inner wall of the cylinder 1. During this process, the thermal grease in the slot 15 conducts the heat generated by the ultrasonic transducers 6 to the outer wall of the cylinder 1 in real time to prevent the ultrasonic transducers 6 from overheating and being damaged. The high-frequency vibration continues for 3-5 minutes, causing cracks to appear inside the scale layer on the surface of the flow vanes 4, destroying the adhesion between the scale layer and the vane surface, and pre-treating for subsequent jet cleaning.

[0050] After the ultrasonic vibration pretreatment is completed, the system synchronously opens the flow valves 20 (electromagnetic proportional valves) on the airflow pipe 21 and the liquid flow pipe 22. The opening of the flow valves 20 is adjusted according to the scale level monitored in the early stage. If it is moderate scale, the medium ratio of the airflow pipe 21 to the liquid flow pipe 22 is adjusted to 3:1; if it is heavy scale, the ratio is adjusted to 2:1. The gas and liquid are fully mixed in the mixing pipe 19 to form a low-pressure gas-liquid mixture, which is then transported through the distribution pipe 3 to the nozzles 16, 17, and 18 on the inner side below it. The three nozzles are arranged in a fan shape, and the spray angle evenly sprays the gas-liquid mixture onto the surface of the flow blade 4, covering key areas such as the steam inlet edge, back arc, and blade tip of the blade, and thoroughly flushing and peeling off the scale layer loosened by the ultrasonic waves.

[0051] Simultaneously with the start of the gas-liquid jet cleaning process, the system activates the solenoid valve 13 on the negative pressure pipe 14, creating a negative pressure environment inside the manifold 11 (which is laid out in a ring along the inner wall of the cylinder 1). The adsorption holes 10 evenly distributed on the inner wall of the manifold 11 generate adsorption force, drawing the scale particles suspended inside the cylinder 1 after being peeled off from the surface of the flow vane 4 into the manifold 11. These particles are then transported through the negative pressure pipe 14 to the collection device outside the cylinder 1, preventing the scale particles from re-attaching to the flow vane 4 or the inner wall of the cylinder 1.

[0052] After the gas-liquid jet cleaning continues, the vibration sensor 7 and temperature sensor 8 continuously monitor the vibration frequency and temperature of the flow vane 4. If the data returns to the mild scaling threshold, the system first closes the flow valve 20 to stop the gas-liquid jet, and then closes the ultrasonic transducer 6 and solenoid valve 13 to complete a single cleaning cycle.

[0053] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0054] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms include and / or encompass are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0055] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0056] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A self-cleaning device for flow vanes in a low-pressure cylinder, comprising a cylinder body (1) and flow vanes (4) disposed inside the cylinder body (1), characterized in that: An ultrasonic transducer (6) is arranged in a ring at the position of the flow vane (4) on the outer wall of the cylinder (1). A collector pipe (11) is fixed on the inner wall of the cylinder (1) on one side of the flow vane (4) by a U-shaped frame (12). A negative pressure pipe (14) connected to the collector pipe (11) is provided on the outer wall of the cylinder (1). The inner wall of the cylinder (1) on the other side of the flow vane (4) is fixed with a distribution pipe (3) by a U-shaped frame (5). A suspension beam (2) is provided between the U-shaped frames (5), and a vibration sensor (7) and a temperature sensor (8) are arranged side by side on the suspension beam (2). A nozzle (16), a nozzle (17), and a nozzle (18) are arranged in a fan shape below the inner side of the distribution pipe (3). A mixing pipe (19) connected to the distribution pipe (3) is provided on the outer side of the cylinder (1), and an airflow pipe (21) and a liquid flow pipe (22) are arranged side by side at the top of the mixing pipe (19).

2. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: The negative pressure pipe (14) and the manifold (11) are both annular structures, and the negative pressure pipe (14) and the manifold (11) are laid along the inner wall of the cylinder (1).

3. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: Both the airflow pipe (21) and the liquid flow pipe (22) are equipped with flow valves (20), and the flow valves (20) are electromagnetic proportional valves whose opening degree can be adjusted by current signal.

4. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: The outer wall of the cylinder (1) is uniformly provided with slots (15) for installing ultrasonic transducers (6), and the inner wall of the slots (15) and the ultrasonic transducers (6) are filled with thermally conductive silicone grease.

5. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: The flow blade (4) is connected to the center of the suspension beam (2) via a connecting shaft (9).

6. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: The inner wall of the manifold (11) is uniformly provided with adsorption holes (10), and the negative pressure pipe (14) is provided with a solenoid valve (13).

7. The self-cleaning device for low-pressure cylinder flow vanes according to claim 1, characterized in that: The vibration sensor (7) and temperature sensor (8) are both covered with a high-temperature resistant ceramic protective shell on the outside of their detection ends, and the surface of the protective shell has a strip-shaped through hole that is perfectly adapted to the sensor detection end.

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