A secondary air measuring dynamic cleaning device

Abstract

The application discloses a secondary air measurement dynamic cleaning device, and belongs to the field of power plant boiler monitoring. The cleaning device comprises a positive pressure main pipe and a negative pressure main pipe installed at the rear end of the positive pressure main pipe. The upper ends of the positive pressure main pipe and the negative pressure main pipe are provided with measuring ports. The two ends of the positive pressure main pipe and the negative pressure main pipe are connected with connecting pipes. The outer end of the connecting pipe of the positive pressure main pipe is provided with a windward pipe. The outer end of the connecting pipe of the negative pressure main pipe is provided with a leeward pipe. The cleaning mechanism comprises a rotating shaft penetratingly and telescopically arranged in the windward pipe and the leeward pipe, a plurality of spring strips fixedly connected with the rotating shaft at positions corresponding to the inside of the pipes along the length direction of the rotating shaft, a hammer body fixedly connected with one end of the spring strip away from the rotating shaft, and a driving piece for driving the rotating shaft to rotate. The cleaning mechanism can realize dynamic cleaning of the inside of the windward pipe and the leeward pipe, effectively avoid dust adsorption and accumulation on the inner wall of the pipes, ensure long-term stable operation of the measuring device, and maintain the measurement accuracy.

Description

Technical Field

[0001] This application relates to the field of power plant boiler monitoring technology, specifically a dynamic cleaning device for secondary air measurement. Background Technology

[0002] In the operation system of thermal power plants, the measurement of air velocity and volume in the primary, secondary, and tertiary air of the boiler, as well as in the flue gas ducts of the desulfurization and denitrification systems, is a crucial link in ensuring the stable, economical, and safe operation of the unit. Accurate air velocity and volume data not only provide core information for boiler combustion optimization, ensuring complete fuel combustion to reduce energy waste, but also effectively control pollutant emissions, reduce equipment failure risks, and play an irreplaceable role in improving the overall efficiency of the entire power generation system.

[0003] Currently, various wind speed and air volume measurement technologies and devices have been developed in the industry. Among them, a modular multi-point wind speed and air volume measurement device disclosed in Chinese utility model patent with authorization announcement number CN211148691U is quite representative. This device adopts a modular design, including a main pipeline module, multiple back-to-back tube measurement modules, and a differential pressure signal processing module. It can be flexibly assembled and combined according to actual site requirements. The multiple back-to-back tube measurement modules can be detachably installed on the main pipeline module according to the required layout, greatly simplifying the installation and disassembly process. Based on the Pitot tube measurement principle, it calculates wind speed by measuring the differential pressure between positive and negative pressure. The differential pressure signal processing module is installed at the top of the main pipeline module, significantly shortening the pressure-conducting pipeline between the pressure tap and the differential pressure signal processing module, thereby reducing the probability of pipeline blockage, reducing pressure signal loss during transmission, and effectively improving the accuracy and real-time performance of the measurement. Meanwhile, the device is also designed with a vibration self-cleaning unit, including a cleaning rod and hammers that are evenly and alternately fixed on the cleaning rod. This is designed to prevent blockage inside the back tube measuring module. The back tube measuring module is installed on the vertical pipe unit by bolt connection, which saves a lot of welding work and reduces the safety risks of on-site installation and construction.

[0004] However, in practical applications, existing vibration self-cleaning units rely on the impact and swing of the cleaning rod and hammer to clean dust. However, due to the weight of the hammer itself, the swing amplitude of the hammer is limited when the wind force is small, resulting in insufficient impact force against the inner wall of the pipe. This makes it difficult to generate enough vibration force inside the pipe, making it difficult to effectively vibrate and remove the dust attached to the pipe wall, thus affecting the long-term stable operation of the measuring device and the continuity of measurement accuracy.

[0005] Therefore, this application provides a dynamic cleaning device for secondary air measurement to solve the above problems. Utility Model Content

[0006] This application provides a dynamic cleaning device for secondary wind measurement, which aims to solve the problems mentioned in the background art, such as the existing vibration self-cleaning unit having a small swing amplitude and insufficient impact force when the wind is low due to the weight limitation of the hammer body, which cannot generate enough vibration force to effectively remove dust from the pipe wall, resulting in easy clogging of the measuring device and affecting the measurement accuracy.

[0007] To achieve the above objectives, this application provides the following technical solution: a secondary air measurement and dynamic cleaning device, comprising a positive pressure main pipe and a negative pressure main pipe installed at the rear end of the positive pressure main pipe, both the upper ends of the positive pressure main pipe and the negative pressure main pipe being provided with measuring ports, both ends of the positive pressure main pipe and the negative pressure main pipe being connected to connecting pipes, the outer end of the connecting pipe of the positive pressure main pipe being fitted with a windward pipe, and the outer end of the connecting pipe of the negative pressure main pipe being fitted with a leeward pipe; further comprising a cleaning mechanism; the cleaning mechanism comprising components respectively inserted through and inserted into the windward pipe and the leeward pipe The system comprises a rotating shaft, multiple spring bars fixedly connected at positions corresponding to the interior of the pipe along the length of the rotating shaft, a hammer fixedly connected to the end of each spring bar away from the rotating shaft, and a drive component for rotating the rotating shaft. The rotating shaft passes through the pipe along a straight vertical line. The drive component includes a vertical shaft fixedly connected to both ends of one of the rotating shafts and arc-shaped blades fixedly connected to the vertical shaft at equal intervals in a ring. Both ends of the rotating shaft are fixedly connected to sprockets, and chains mesh with the sprockets. The arc-shaped blades in the drive component rotate under wind power, driving the rotating shaft connected to them to rotate via the vertical shaft. The sprockets at both ends of this rotating shaft drive the other rotating shaft to rotate synchronously via chains. When the rotating shaft rotates, it causes the spring bars to move in an arc shape, which in turn drives the hammer to move upwards along the arc trajectory. During this process, the hammer strikes the inner wall of the pipe, shaking off the attached dust and achieving dynamic cleaning.

[0008] Preferably, to avoid scratching the inner wall of the pipe with the hammer, the hammer body has a spherical structure. Using a spherical structure avoids scratching the inner wall of the pipe when hammering, protecting the integrity of the inner surface of the pipe, extending the service life of the pipe, and ensuring that the cleaning effect of the hammering is not affected.

[0009] Preferably, to prevent dust from affecting the sprockets and chain, a protective shell is fitted over the outer sides of the two sprockets and the chain. The protective shell is connected to the positive and negative pipes via a bracket. Lubricating oil is provided inside the protective shell, and the rotating shaft is rotatably connected to the protective shell. This effectively prevents dust from entering the meshing area of ​​the sprockets and chain, preventing dust from adhering to the sprockets and chain and affecting their transmission performance. Simultaneously, the internal lubricating oil reduces friction and wear between the sprockets and chain, improving transmission efficiency and service life, and reducing maintenance costs.

[0010] Preferably, the rotating shaft is connected to the protective housing via a sealed bearing. This ensures the rotating shaft can rotate freely while effectively preventing lubricating oil leakage from inside the protective housing and preventing external dust from entering the housing, maintaining a sealed environment and lubrication effect inside the housing, and ensuring the normal operation of the sprocket and chain.

[0011] Preferably, the windward duct has sloping air inlets at both its upper and lower ends, and the leeward duct has horizontal air inlets at both its upper ends. The sloping air inlets of the windward duct help to capture airflow more efficiently, increase the air volume, and improve the sensitivity and accuracy of the measurement; the horizontal air inlets of the leeward duct can meet the requirements of measuring negative pressure, ensuring the acquisition of a stable negative pressure signal, thereby making the measurement of positive and negative pressure more accurate and providing reliable data for wind speed calculation.

[0012] Preferably, the cutting angle of the inclined surface air inlet is 45 to 60 degrees. This angle range can ensure that the airflow is effectively captured by the duct while avoiding excessive airflow resistance, making the airflow more stable and reducing the impact of airflow disturbance on measurement accuracy. It is suitable for the wind speed range and flow characteristics of secondary air in thermal power plants.

[0013] Preferably, the measuring port is equipped with a differential pressure signal processing module for processing the measured differential pressure signal. This module can directly process the positive and negative differential pressure signals acquired by the measuring port, shortening the signal transmission path, reducing signal loss and interference, improving the timeliness and accuracy of signal processing, and thus enhancing the accuracy and real-time performance of wind speed measurement, providing more reliable data support for boiler combustion optimization.

[0014] This application utilizes a cleaning mechanism to achieve dynamic cleaning of the interior of both the windward and leeward ducts, effectively preventing dust from adsorbing and accumulating on the inner walls of the ducts, ensuring long-term stable operation of the measuring device, and maintaining measurement accuracy. Driven by wind power, it requires no additional power source, saving energy, and the cleaning process is continuous. The cleaning effect is significantly better than traditional vibration self-cleaning methods, and it is not limited by wind strength, providing excellent cleaning performance under various working conditions. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a dynamic cleaning device for measuring secondary airflow.

[0016] Figure 2 for Figure 1 Enlarged view of the middle section structure;

[0017] Figure 3 This is a schematic diagram of the drive component.

[0018] In the picture:

[0019] 1. Positive pressure main pipe; 11. Windward pipe; 2. Negative pressure main pipe; 21. Backwind pipe; 3. Measuring port; 4. Connecting pipe; 5. Cleaning mechanism; 51. Rotating shaft; 52. Spring bar; 53. Hammer body; 54. Drive component; 541. Vertical shaft; 542. Arc blade; 543. Sprocket; 544. Chain; 545. Protective shell. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] Example 1

[0022] This embodiment provides a dynamic cleaning device for secondary air measurement, such as... Figure 1-3As shown, the cleaning device includes a positive pressure main pipe 1 and a negative pressure main pipe 2 installed at the rear end of the positive pressure main pipe 1. Measuring ports 3 are provided at the upper ends of both the positive pressure main pipe 1 and the negative pressure main pipe 2. Connecting pipes 4 are connected to both ends of the positive pressure main pipe 1 and the negative pressure main pipe 2. A windward pipe 11 is installed at the outer end of the connecting pipe 4 of the positive pressure main pipe 1, and a leeward pipe 21 is installed at the outer end of the connecting pipe 4 of the negative pressure main pipe 2. It also includes a cleaning mechanism 5. The cleaning mechanism 5 includes a rotating shaft 51 that passes through and is inserted into the windward pipe 11 and the leeward pipe 21 respectively, and a shaft 51 extending along its length and perpendicular to the interior of the pipe. Multiple spring bars 52, a hammer body 53 fixedly connected to the end of the spring bars 52 away from the rotating shaft 51, and a driving component 54 for driving the rotating shaft 51 to rotate are fixedly connected at the corresponding positions. The rotating shaft 51 passes through a pipe located on the same straight line vertically. The driving component 54 includes a vertical shaft 541 fixedly connected to both ends of one of the rotating shafts 51 and arc-shaped blades 542 fixedly connected to the vertical shaft 541 at equal intervals along a ring. Both ends of the rotating shaft 51 are fixedly connected to sprockets 543, and chains 544 meshing with them are fitted on the two sprockets 543. The cleaning mechanism 5 can realize dynamic cleaning of the inside of the windward pipe 11 and the leeward pipe 21, effectively preventing dust from adsorbing and accumulating on the inner wall of the pipe, ensuring the long-term stable operation of the measuring device, and maintaining the measurement accuracy. Driven by wind power, no additional power source is required, saving energy. The cleaning process is continuous, and the cleaning effect is significantly better than the traditional vibration self-cleaning method. It is not limited by the wind force and can play a good cleaning role under various working conditions. The arc-shaped blades 542 in the drive unit 54 rotate under the action of wind power, driving the connected rotating shaft 51 to rotate via the vertical shaft 541. The sprockets 543 at both ends of the rotating shaft 51 drive another rotating shaft 51 to rotate synchronously via the chain 544. When the rotating shaft 51 rotates, it drives the spring strip 52 to make an arc-shaped motion. The spring strip 52 then drives the hammer body 53 to move from bottom to top along the arc-shaped trajectory. During this process, the hammer body 53 hammers the inner wall of the pipe, shaking off the attached dust and achieving dynamic cleaning.

[0023] To prevent the hammer 53 from scratching the inner wall of the pipe, the hammer 53 has a spherical structure. This spherical structure prevents scratches on the inner wall of the pipe during hammering, protecting the integrity of the inner surface, extending the pipe's service life, and ensuring the cleaning effect is not affected. When the spherical hammer 53 moves with the spring strip 52 and comes into contact with the inner wall of the pipe, its curved surface makes point contact with the inner wall. Compared to a structure with sharp edges, the contact area is small and the force is evenly distributed, preventing scratches and thus avoiding damage to the inner wall of the pipe.

[0024] To prevent dust from affecting sprockets 543 and chain 544, a protective shell 545 is fitted over the outer sides of both sprockets 543 and chain 544. The protective shell 545 is connected to the positive and negative pipes via a bracket. Lubricating oil is installed inside the protective shell 545, and the rotating shaft 51 is rotatably connected to it. This effectively prevents dust from entering the meshing area of ​​sprockets 543 and chain 544, preventing dust from adhering to them and affecting their transmission performance. Simultaneously, the internal lubricating oil reduces friction and wear between sprockets 543 and chain 544, improving transmission efficiency and service life, and reducing maintenance costs. The protective shell 545, fitted over the outer sides of sprockets 543 and chain 544, forms a relatively enclosed space, isolating dust from them. The internal lubricating oil forms an oil film on the surfaces of sprockets 543 and chain 544 during movement, reducing direct friction and providing some dust protection.

[0025] The rotating shaft 51 is connected to the protective housing 545 via a sealed bearing. This ensures the rotating shaft 51 can rotate freely while effectively preventing lubricating oil leakage from inside the protective housing 545 and preventing external dust from entering the housing. It maintains a sealed environment and lubrication effect inside the protective housing 545, ensuring the normal operation of the sprocket 543 and chain 544. The sealed bearing has sealing properties; its sealing ring tightly fits the mounting holes of the rotating shaft 51 and the protective housing 545. During the rotation of the shaft 51, it reduces rotational resistance, prevents lubricating oil leakage from gaps, and blocks external dust from entering the protective housing 545 through gaps.

[0026] The windward duct 11 has sloping air inlets at both its upper and lower ends, while the leeward duct 21 has horizontal air inlets at both its upper ends. The sloping air inlets of the windward duct 11 facilitate more efficient airflow capture, increase air volume, and improve measurement sensitivity and accuracy. The horizontal air inlets of the leeward duct 21 meet the requirements for measuring negative pressure, ensuring a stable negative pressure signal, thus making the measurement of positive and negative pressure more accurate and providing reliable data for wind speed calculation. The windward duct 11 needs to measure positive pressure; the sloping air inlets form an angle with the airflow direction, better catching the airflow and allowing it to enter the windward duct 11 more smoothly, enhancing the positive pressure signal. The leeward duct 21 is used to measure negative pressure; the horizontal air inlets meet the requirements for airflow acquisition during negative pressure measurement, stably collecting negative pressure information within the duct. Combined with the positive pressure signal from the windward duct 11, wind speed is calculated through differential pressure.

[0027] The cutting angle of the ramp air inlet is 45–60 degrees. This angle range ensures that the air inlet 11 effectively captures the airflow while avoiding excessive airflow resistance, resulting in smoother airflow and reducing the impact of airflow disturbance on measurement accuracy. It is suitable for the wind speed range and flow characteristics of secondary air in thermal power plants. The cutting angle of 45–60 degrees creates a suitable angle between the ramp air inlet and the airflow. When the secondary airflow passes through, it can smoothly enter the air inlet 11. This avoids insufficient airflow due to an angle that is too small, or airflow turbulence caused by a sharp increase in airflow resistance due to an angle that is too large, thus ensuring the stability and accuracy of positive pressure measurement.

[0028] The measuring port 3 is equipped with a differential pressure signal processing module for processing the measured differential pressure signals. It can directly process the positive and negative differential pressure signals acquired through measuring port 3, shortening the signal transmission path, reducing signal loss and interference, and improving the timeliness and accuracy of signal processing. This, in turn, enhances the accuracy and real-time performance of wind speed measurement, providing more reliable data support for boiler combustion optimization. The measuring ports 3 of the positive pressure main pipe 1 and the negative pressure main pipe 2 respectively acquire positive and negative pressure signals. The differential pressure signal processing module is directly installed within measuring port 3, enabling it to quickly receive these differential pressure signals and perform amplification, filtering, and calculations to obtain accurate wind speed data, avoiding various interferences and attenuations that occur during long-distance signal transmission.

[0029] It should be noted that many of the standard parts used in this application are available on the market, while non-standard parts can be specially customized. The connection method used in this application is also a very common method in the mechanical field, and will not be described in detail here.

[0030] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and concept of this application, should be included within the scope of protection of this application.

Claims

1. A dynamic cleaning device for measuring secondary airflow, comprising a positive pressure main pipe (1) and a negative pressure main pipe (2) installed at the rear end of the positive pressure main pipe (1), wherein the upper ends of the positive pressure main pipe (1) and the negative pressure main pipe (2) are provided with measuring ports (3), and both ends of the positive pressure main pipe (1) and the negative pressure main pipe (2) are connected to connecting pipes (4), wherein the outer end of the connecting pipe (4) of the positive pressure main pipe (1) is provided with a windward pipe (11), and the outer end of the connecting pipe (4) of the negative pressure main pipe (2) is provided with a leeward pipe (21). It also includes cleaning agencies (5); Its features are: The cleaning mechanism (5) includes a rotating shaft (51) that is inserted through the windward pipe (11) and the leeward pipe (21), a plurality of spring strips (52) that are fixedly connected at positions corresponding to the inside of the pipe along the length direction of the rotating shaft (51), a hammer (53) that is fixedly connected to one end of the spring strips (52) away from the rotating shaft (51), and a driving member (54) for driving the rotating shaft (51) to rotate; wherein the rotating shaft (51) passes through the pipe located on the same straight line from top to bottom; The drive unit (54) includes a vertical shaft (541) fixedly connected to both ends of one of the shafts (51) and an arc-shaped blade (542) fixedly connected to the vertical shaft (541) at equal intervals along a ring. Both ends of the shaft (51) are fixedly connected to sprockets (543), and chains (544) meshing with the two sprockets (543) are fitted on them.

2. The secondary wind measurement and dynamic cleaning device according to claim 1, characterized in that: The hammer (53) has a spherical structure.

3. The secondary wind measurement and dynamic cleaning device according to claim 1, characterized in that: A protective shell (545) is fitted over the outer side of the two sprockets (543) and the chain (544). The protective shell (545) is connected to the positive and negative pipes of the pipeline through a bracket. The protective shell (545) is filled with lubricating oil. The rotating shaft (51) is rotatably connected to the protective shell (545).

4. The secondary wind measurement and dynamic cleaning device according to claim 3, characterized in that: The rotating shaft (51) is connected to the protective shell (545) via a sealed bearing.

5. The secondary wind measurement and dynamic cleaning device according to claim 1, characterized in that: The windward pipe (11) has sloping air inlets at both the upper and lower ends, and the leeward pipe (21) has horizontal air inlets at both the upper ends.

6. The secondary wind measurement and dynamic cleaning device according to claim 5, characterized in that: The cutting angle of the slope air inlet is 45 to 60 degrees.

7. The secondary wind measurement and dynamic cleaning device according to claim 1, characterized in that: The measuring port (3) is equipped with a differential pressure signal processing module for processing the measured differential pressure signal.

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