Device suitable for adjusting flow speed in wind powder pipeline of power station boiler

Abstract

The utility model relates to the technical field of fluid flow regulation and control, in particular to a device suitable for regulating the flow speed in a wind powder pipeline of a power station boiler, which comprises a mounting box, the mounting box is vertically arranged on a horizontal pipeline and communicated with the horizontal pipeline, and the horizontal pipeline is provided with a flow regulating valve. A lifting mechanism arranged on the mounting box is connected with an adjusting rod so as to drive the adjusting rod to move in the radial direction of the horizontal pipeline, the adjusting rod penetrates into the mounting box and is connected with the main rod, and a plurality of supporting rods are connected to the main rod side by side at equal intervals so as to form a comb-shaped structure. A special connection mode of the main rod and the supporting rods is adopted, the through-flow area of the wind powder horizontal pipeline can be changed by driving the supporting rods to move, the flow speed of airflow in the horizontal pipeline is adjusted, the installation box and the horizontal pipeline are connected without cutting off the horizontal pipeline, installation can be conducted only through slotting, the construction difficulty and workload are greatly reduced, and the construction efficiency is improved. Dust is not easy to accumulate in the mounting box, so that the reliability of the device is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of fluid flow regulation and control, in particular to a device suitable for regulating flow velocity in an air-powder pipeline of a power station boiler. Background Art

[0002] At present, my country's electricity supply is still dominated by thermal power generation. Thermal power generation uses raw coal as the primary energy source. Usually, the raw coal is ground into coal powder first, and then sent into the boiler for combustion with hot air. With the improvement of the manufacturing industry, the capacity of single boilers is getting larger and larger. Usually, the coal powder sent into the boiler is divided into dozens of horizontal pipes. Whether the air-powder flow in each horizontal pipe is uniform will directly affect the safety and economy of boiler combustion. However, since each horizontal pipe is of different lengths and arrangements, the size of the resistance is definitely different, and it is inevitable that the flow in the pipe will deviate. This requires the air-powder flow in each horizontal pipe to be adjusted. At present, the flow regulating equipment used in the horizontal air-powder pipe of the boiler in China is mainly divided into two categories: one is an adjustable shrinkage hole, and the other is a circular adjustable baffle door.

[0003] The first type, the so-called adjustable shrinkage hole, is to use two approximately semicircular split gate plates on an end face of the horizontal air-powder pipe. The flow area can be changed by moving the gate plates. Moving the gate plates toward the center of the horizontal pipe can reduce the flow area, moving them in the opposite direction can expand the flow area or fully open them. The adjustable shrinkage hole is theoretically feasible. In actual use, since the two gate plates are arranged in two spaces respectively, the space will inevitably be blocked by coal powder after a long time, and the moisture in the coal powder is also easy to condense, causing the coal powder to agglomerate and solidify. This makes almost all the shrinkage holes stuck and unable to be adjusted. It is inconvenient to dismantle it for manual cleaning and reassembly. In addition, when installing the adjustable shrinkage hole, the horizontal air-powder pipe must be cut off and fixed with a flange. The diameter of the horizontal air-powder pipe is relatively large, generally about 650mm, and the wall thickness is about 12mm, which requires a lot of work and is not safe.

[0004] The second type is a circular adjustable baffle door, which also cuts off the entire horizontal pipeline and is installed in the air-powder horizontal pipeline through a flange. The flow rate is adjusted by changing the angle of the circular adjustable baffle in the pipeline. Its shortcomings are that it is troublesome to install, and on the other hand, the circular adjustable baffle has a certain angle when adjusted in the pipeline. When the coal powder encounters the baffle surface, it will change direction and shoot toward the inner wall of the air-powder horizontal pipeline. Long-term operation may even wear through the air-powder pipeline wall. In addition, the flow blocking area in the pipeline is large. Even if it is fully opened, there is still 15~20% of the flow blocking area. Among dozens of air-powder pipes, there are always a few that need to fully open the adjusting door due to large resistance. That is to say, even if the circular baffle adjusting door is fully opened, there is still a large flow resistance, and the baffle adjusting shaft is also easily worn, thereby shortening the service life of the adjusting shaft. Utility Model Content

[0005] The utility model aims to solve the above defects and provides a device suitable for regulating the flow rate in the air-powder pipeline of a power station boiler.

[0006] In order to overcome the defects existing in the background technology, the technical solution adopted by the utility model to solve its technical problems is: a device suitable for adjusting the flow rate in the air-powder duct of a power station boiler, comprising an installation box, the installation box is vertically arranged on a horizontal duct, and the installation box is connected to the horizontal duct, the lifting mechanism arranged on the installation box is connected to the adjusting rod to drive the adjusting rod to move in the radial direction of the horizontal duct, the adjusting rod is inserted into the installation box and connected to the main rod, and a plurality of support rods are connected to the main rod side by side and equidistantly to form a comb-shaped structure.

[0007] A further improvement includes forming an arc-shaped structure at the end of the support rod to match and fit the inner wall of the horizontal pipe.

[0008] A further improvement includes providing a wear-resistant plate on the flow-facing surface of the support rod.

[0009] A further improvement includes providing a rolling portion on the main rod, and the rolling portion is rollingly arranged on the inner wall of the installation box.

[0010] A further improvement includes the adjustment rod being inserted into the installation box after passing through an airtight box provided on the installation box, and the airtight box being provided with an air supply pipe for supplying compressed air into the airtight box.

[0011] Further improvements include that the lifting mechanism includes a carrying plate arranged on the installation box, a stepper motor and a screw arranged on the carrying plate, two fixed seats are arranged opposite to each other on the carrying plate, a screw is rotatably arranged between the fixed seats, one end of the screw is connected to the output end of the stepper motor to drive the screw to rotate, an adjusting slider connected to the adjusting rod with a thread on the screw is driven to move along the axial direction of the screw, and the adjusting slider is slidably arranged on the carrying plate.

[0012] A further improvement includes at least two adjusting sliders being threadedly connected to the screw rod.

[0013] The beneficial effects of the utility model are as follows: the design adopts a connection method of a comb-shaped structure of a main rod and a support rod, and the flow area of ​​the horizontal air-powder duct can be changed by driving the support rod to move, thereby realizing the adjustment of the airflow velocity in the horizontal duct, and the installation box is connected to the horizontal duct without cutting the horizontal duct, and only a slit is needed for installation, which greatly reduces the construction difficulty and workload, and dust is not easy to accumulate in the installation box, which greatly improves the reliability of the device; the wear-resistant plate improves the wear resistance of the support rod and extends the service life of the support rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 It is the front view of the utility model;

[0016] Figure 2 It is a right view of the utility model;

[0017] In the figure, 1-installation box, 2-support rod, 3-air pipe, 4-adjusting rod, 5-adjusting slider, 6-stepping motor, 7-fixing seat, 8-bearing plate, 9-airtight box, 10-main rod, 11-wear-resistant plate, 12-horizontal pipeline, 13-screw rod, 14-rolling part. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. The embodiments in the basic utility model and all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] according to Figure 1 and Figure 2 As shown, a device suitable for regulating the flow rate in an air-powder duct of a power station boiler comprises an installation box 1, wherein the installation box 1 is vertically arranged on a horizontal duct 12, and the installation box 1 is communicated with the horizontal duct 12, a lifting mechanism arranged on the installation box 1 is connected to an adjusting rod 4, thereby driving the adjusting rod 4 to move in the radial direction of the horizontal duct 12, the adjusting rod 4 is penetrated into the installation box 1 and connected to the main rod 10, a plurality of support rods 2 are connected to the main rod 10 in parallel and equidistantly to form a comb-shaped structure, the support rods 2 are driven by the lifting mechanism to be radially inserted into the horizontal duct 12 to regulate the air-powder flow rate in the horizontal duct 12, and when the air-powder airflow passes between the support rods 2, the coal powder flows through the gaps between the support rods 2, thereby preventing the airflow from being deviated to one side and wearing the inner wall of the air-powder horizontal duct 12.

[0020] In this design, it is only necessary to make a slit in the arc range of about one-third above the horizontal pipe 12, and install the installation box 1 on the horizontal pipe 12, which greatly reduces the construction difficulty and workload. The installation box 1 is vertically arranged on the horizontal pipe 12, and coal powder is not easy to accumulate in the entire installation box 1. Even if some coal powder accumulates on the inner wall of the installation box 1, the lifting mechanism drives the support rod 2 to move to shake off the coal powder on the inner wall of the installation box 1, and the coal powder re-enters the horizontal pipe 12, solving the problem of powder accumulation in the adjustable shrinkage hole adjustment space and greatly improving the reliability of the device. This comb-shaped assembly method of the main rod 10 and the support rod 2 prevents the support rod 2 from reducing the flow in the entire horizontal pipe 12 to zero when the horizontal pipe 12 is fully closed, thereby affecting the safety of the unit equipment.

[0021] The end of the support rod 2 forms an arc structure that matches and fits with the inner wall of the horizontal pipe 12. When the support rod 2 is fully inserted into the horizontal pipe 12, the arc surface of the support rod 2 fits with the inner wall of the horizontal pipe 12. Since there are gaps between the support rods 2, wind and powder still pass through the gaps at this time. According to a large number of tests and the resistance characteristics of the wind and powder horizontal pipe 12, this design retains one-third of the flow area in the fully closed state.

[0022] In order to increase the service life of the support rod 2 and improve the wear resistance of its surface, a wear-resistant plate 11 is provided on the upstream surface of the support rod 2. The wear-resistant plate 11 is made of aluminum oxide. Since the support rod 2 will be directly eroded by wind powder, the general material will wear quickly. This design greatly increases the service life of the support rod 2.

[0023] In order to meet the needs of automation, the lifting mechanism includes a carrying plate 8 arranged on the installation box 1, a stepper motor 6 and a screw 13 arranged on the carrying plate 8. Two fixed seats 7 are relatively arranged on the carrying plate 8. The screw 13 is rotatably arranged between the fixed seats 7. One end of the screw 13 is connected to the output end of the stepper motor 6 to drive the screw 13 to rotate. The screw 13 is threadedly connected to an adjusting slider 5 connected to the adjusting rod 4 to drive the adjusting slider 5 to move axially along the screw 13, and the adjusting slider 5 is slidably arranged on the carrying plate 8. In a further embodiment, at least two adjusting sliders 5 are threadedly connected to the screw 13. This design method is beneficial to improving the stability of sliding, and is also beneficial to balancing the force applied to the adjusting rod 4 by the balance support rod 2 after being subjected to force in the horizontal pipe 12.

[0024] In order to reduce the influence of the support rod 2 on the adjusting rod 4 when the force is applied, a rolling portion 14 is arranged on the main rod 10, and the rolling portion 14 is arranged to roll on the inner wall of the installation box 1. The rolling portion 14 rolls on the inner wall of the installation box 1 as the adjusting rod 4 moves, so as to balance the force applied to the support rod 2 in the wind and powder horizontal duct 12. The rolling portion 14 is preferably a universal ball or a universal wheel.

[0025] Since the pressure in the horizontal pipeline 12 is higher than the atmospheric pressure, when the adjusting rod 4 is inserted into the installation box 1 and moves, wind and powder will appear at the connection between the installation box 1 and the adjusting rod 4. In order to prevent this phenomenon from occurring, an airtight box 9 is provided. The adjusting rod 4 passes through the airtight box 9 provided on the installation box 1 and then is inserted into the installation box 1. The airtight box 9 is provided with an air supply pipe 3 for conveying compressed air to the airtight box 9. The adjusting rod 4 passes through the airtight box 9. The connection between the airtight box 9 and the adjusting rod 4 is tightly matched, and the gap is very small, which is equivalent to the sliding of the piston. Compressed air is input through the air supply pipe 3 so that the air pressure in the airtight box 9 is higher than the air pressure in the horizontal pipeline 12. Since the pressure in the airtight box 9 is higher than the pressure in the horizontal pipeline 12, the wind and powder in the horizontal pipeline 12 will not bubble out. At the same time, the sliding gap of the adjusting rod 4 in the airtight box 9 is small, and almost no compressed air needs to be consumed. Such a design neither wastes energy nor has a good sealing effect.

[0026] Working principle: Start the stepper motor 6, the stepper motor 6 drives the screw rod 13 to rotate, thereby driving the adjusting rod 4 to move, and the adjusting rod 4 drives the support rod 2 to be radially and vertically inserted into the horizontal pipe 12. By inserting the support rod 2 into the horizontal pipe 12, the force surface of the support rod 2 is changed, thereby adjusting the air flow rate in the horizontal pipe 12. At the same time, the external air source transports compressed air to the airtight box 9 through the air pipe 3.

[0027] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for regulating flow rate in air-powder pipeline of power station boiler, characterized in that: The invention comprises an installation box (1), wherein the installation box (1) is vertically arranged on a horizontal pipe (12), and the installation box (1) is connected to the horizontal pipe (12); a lifting mechanism arranged on the installation box (1) is connected to an adjusting rod (4) so ​​as to drive the adjusting rod (4) to move in the radial direction of the horizontal pipe (12); the adjusting rod (4) is inserted into the installation box (1) and connected to a main rod (10); and a plurality of supporting rods (2) are connected to the main rod (10) in parallel and at equal distances so as to form a comb-shaped structure.

2. A device for regulating flow rate in an air-powder duct of a power station boiler as claimed in claim 1, characterized in that: The end of the support rod (2) forms an arc-shaped structure that matches and fits the inner wall of the horizontal pipe (12).

3. A device for regulating flow rate in an air-powder duct of a power station boiler as claimed in claim 1, characterized in that: A wear-resistant plate (11) is provided on the flow-facing surface of the support rod (2).

4. A device for regulating flow rate in an air-powder duct of a power station boiler as claimed in claim 1, characterized in that: A rolling portion (14) is provided on the main rod (10), and the rolling portion (14) is arranged to roll on the inner wall of the installation box (1).

5. A device for regulating flow rate in an air-powder duct of a power station boiler as claimed in claim 1, characterized in that: The adjusting rod (4) is inserted into the installation box (1) after passing through an airtight box (9) provided on the installation box (1), and an air supply pipe (3) for supplying compressed air into the airtight box (9) is provided on the airtight box (9).

6. A device for regulating flow rate in an air-powder duct of a power station boiler as claimed in any one of claims 1 to 5, characterized in that: The lifting mechanism comprises a bearing plate (8) arranged on the installation box (1), a stepper motor (6) and a screw rod (13) arranged on the bearing plate (8); two fixing seats (7) are arranged on the bearing plate (8) in a relative manner; a screw rod (13) is rotatably arranged between the fixing seats (7); one end of the screw rod (13) is connected to the output end of the stepper motor (6) so as to drive the screw rod (13) to rotate; an adjusting slider (5) connected to the adjusting rod (4) is threadedly connected on the screw rod (13) so as to drive the adjusting slider (5) to move axially along the screw rod (13); and the adjusting slider (5) is slidably arranged on the bearing plate (8).

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