Pneumatic isolation mill hot air door

Abstract

The utility model belongs to hot air door technical field especially, and a kind of pneumatic isolation coal mill hot air door including door frame, door panel, door panel includes arc seat;The outside of arc seat is provided with a plurality of first rotary scraper and second rotary scraper for removing coal ash, first rotary scraper and second rotary scraper synchronous motion, the included angle formed by first rotary scraper and second rotary scraper and arc seat tangent in initial state is respectively alpha and beta, the angle of alpha and beta is all not more than 90 °, the utility model solves the problem that hot air door leads to plug-in door movement jamming due to coal ash, the coal ash in the deep of the sliding slot inside door frame can be cleaned under the condition of not stopping machine disassembly by the switching action of door panel, maintenance time is reduced, avoid the work efficiency decline caused by stopping machine.

Description

Technical Field

[0001] This utility model belongs to the field of hot air door technology, specifically relating to a pneumatic isolation hot air door for a coal mill. Background Technology

[0002] The hot air damper of a coal mill is a key component of the auxiliary equipment of a coal mill in thermal systems such as coal-fired power plants and industrial boilers. Its core function is to ensure the normal operation of the coal mill, optimize the quality of pulverized coal preparation, and work in synergy with the entire thermal system to achieve safe and efficient operation by adjusting the flow of hot air. The functions of the hot air damper are: firstly, to dry the moisture in the raw coal to achieve the ideal grinding humidity, thereby preventing raw coal with excessive moisture from sticking inside the coal mill and affecting grinding efficiency; secondly, to control the flow rate of hot air and precisely adjust the temperature of the pulverized coal mixture at the coal mill outlet, avoiding excessively low temperatures that could affect the drying of the raw coal and excessively high temperatures that could cause pulverized coal explosions.

[0003] After prolonged use, common circular hot air dampers with slide plates accumulate a large amount of coal ash deep within their internal grooves. Since one side of the hot air damper connects to the coal mill and the other side connects to the hot air duct, cleaning the coal ash deep within the internal grooves is difficult, especially in the arc-shaped grooves. While coal ash in straight grooves can be cleaned by scraping as the damper slides, cleaning the arc-shaped grooves is extremely troublesome. If the machine is stopped and disassembled for cleaning, it will undoubtedly affect work efficiency and may also disrupt the coordination between devices during subsequent installation. If left unattended, the accumulated coal ash will cause the damper to jam, affecting its control over the hot air. Utility Model Content

[0004] To address the problems mentioned in the background section, this invention provides a pneumatically operated hot air door for a coal mill, which features the ability to clean coal ash and ensure flexible opening and closing of the slide gate.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a pneumatic isolation coal mill hot air door, including a door frame and a door panel, the door panel including an arc-shaped seat; a plurality of first rotating scrapers and second rotating scrapers for removing coal ash are arranged on the outer side of the arc-shaped seat, the first rotating scrapers and the second rotating scrapers move synchronously, and in the initial state, the angles formed by the first rotating scraper and the second rotating scraper and the tangent of the arc-shaped seat are α and β respectively, and the angles of α and β are not greater than 90°.

[0006] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, when the first rotating scraper comes into contact with the inner groove of the door frame, the second rotating scraper does not come into contact with the inner groove of the door frame.

[0007] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, a connecting cable is provided on the outer side of the first rotating scraper to pull the second rotating scraper to move synchronously.

[0008] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, one side of the first rotating scraper and the second rotating scraper is provided with sharp teeth for cleaning coal ash inside the placement trough.

[0009] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, a pointed cone for cleaning coal ash is provided on the outer side of the arc-shaped seat.

[0010] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, a sealing surface is provided on the outer side of the arc-shaped seat.

[0011] As a preferred embodiment of the pneumatic isolation coal mill hot air door of this utility model, a fixing plate for scraping coal ash from the straight groove of the door frame is provided on the outer side of the door panel.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. By opening and closing the door panel, the coal ash deep inside the sliding groove of the door frame can be cleaned without stopping the machine, reducing maintenance time, avoiding downtime and reduced work efficiency, and also protecting the coordination between devices.

[0014] 2. The first rotating scraper cleans the coal ash, which can reduce the coal ash accumulation inside the door frame, prevent the door panel from getting stuck during opening and closing, maintain the flexibility of the door panel when opening and closing, and ensure precise control of the hot air flow. Attached Figure Description

[0015] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0017] Figure 2 This is a structural schematic diagram of the cross-section of the door frame in this utility model;

[0018] Figure 3 This is a schematic diagram of the door panel structure in this utility model;

[0019] Figure 4 In this utility model Figure 3 A magnified structural diagram at point A;

[0020] Figure 5 In this utility model Figure 3A magnified structural diagram at point B;

[0021] Figure 6 This is a schematic diagram of the torsion spring mounting structure in this utility model;

[0022] In the picture:

[0023] 1. Door frame; 2. Door panel; 3. Arc-shaped seat; 4. First rotating scraper; 5. Connecting cable; 6. Second rotating scraper; 7. Cone; 8. Teeth; 9. Mounting groove; 10. Sealing surface; 11. Pneumatic device; 12. Fixing plate; 13. Torsion spring. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] like Figures 1-6 As shown:

[0026] A pneumatic isolation hot air door for a coal mill includes a door frame 1 and a door panel 2. The door panel 2 includes an arc-shaped seat 3. Several first rotating scrapers 4 and second rotating scrapers 6 for removing coal ash are arranged on the outer side of the arc-shaped seat 3. The first rotating scrapers 4 and the second rotating scrapers 6 move synchronously. In the initial state, the included angles formed by the first rotating scrapers 4 and the second rotating scrapers 6 and the tangent of the arc-shaped seat 3 are α and β, respectively, and the angles of α and β are not greater than 90°. When using a slide-type hot air damper, the pneumatic device 11 drives the door panel 2 to move, opening and closing the hot air damper and regulating the hot air flow. However, the inner groove of the door frame 1 accumulates a large amount of coal ash over time. This coal ash not only affects the flexibility of opening and closing the door panel 2 but also damages the sealing line of the hot air damper. As the door panel 2 gradually closes, the first rotating scraper 4 contacts the inner groove of the door frame 1 and rotates to one side. While rotating, the first rotating scraper 4 cleans the accumulated coal ash in the groove. This cleaning action by the first rotating scraper 4 prevents excessive coal ash accumulation inside the groove, ensuring the sealing effect of the hot air damper and precise control of the hot air flow. The first rotating scraper 4 and the second rotating scraper 6 are reset by the torsion spring 13 when the door panel 2 is opened, ensuring continuous use in subsequent operations.

[0027] α represents the angle formed by the center line of the first rotating scraper 4 and the tangent of the arc-shaped seat 3, and β represents the angle formed by the center line of the second rotating scraper 6 and the tangent of the arc-shaped seat 3. The other side of the angle α formed between the first rotating scraper 4 and the arc-shaped seat 3 is limited by the arc-shaped seat 3, and the other side of the angle β formed between the second rotating scraper 6 and the arc-shaped seat 3 is limited by the arc-shaped seat 3.

[0028] Furthermore, when the first rotating scraper 4 contacts the internal groove of the door frame 1, the second rotating scraper 6 does not contact the internal groove of the door frame 1. Because coal ash accumulates in the internal groove of the door frame 1, this ash not only affects the sealing performance of the sliding door but also reduces the smoothness of the inner wall of the groove. When both the first rotating scraper 4 and the second rotating scraper 6 are in contact with the internal groove of the door frame 1, the second rotating scraper 6 will not contact the internal groove of the door frame 1. This is due to the different rotational positions of the two scrapers, thereby reducing the amount of force exerted when the first rotating scraper 4 and the second rotating scraper 6 contact the door frame 1, and also preventing excessive friction from affecting the opening and closing speed of the door panel 2.

[0029] In an optional embodiment, a connecting cable 5 is provided on the outer side of the first rotating scraper 4 to pull the second rotating scraper 6 to move synchronously.

[0030] When the first rotating scraper 4 comes into contact with the inner groove of the door frame 1 and rotates to one side, the second rotating scraper 6 is pulled to rotate together through the connecting cable 5, so as to avoid the first rotating scraper 4 and the second rotating scraper 6 rubbing against the door frame 1 multiple times and slow down the opening and closing speed of the door panel 2.

[0031] While the first rotating scraper 4 pulls the second rotating scraper 6 to move together, the second rotating scraper 6 is a certain distance away from the inner groove of the door frame 1 and will not come into contact with it. Thus, when the second rotating scraper 6 rotates, it will not rub against the inner wall of the inner groove of the door frame 1, avoiding excessive friction that could affect the opening and closing speed of the door. At the same time as the second rotating scraper 6 rotates, it will also clean the coal ash inside the groove. Although it does not clean all the coal ash inside the groove, it will damage the structure of the coal ash during the cleaning process. Subsequently, the coal ash with the damaged structure will be cleaned away by the wind and the vibration force of the device itself during operation. In addition, there is a certain gap between the door frame 1 and the arc-shaped seat 3 of the door panel 2, so even if there is some coal ash, it will not affect the operation of the hot air door.

[0032] The connecting cable 5 can be made of aramid rope, stainless steel wire rope, etc. These materials not only have a certain degree of flexibility, but also have a high cost performance and a wide range of applications.

[0033] In an optional embodiment, one side of the first rotating scraper 4 and the second rotating scraper 6 is provided with sharp teeth 8 for cleaning the coal ash inside the placement groove 9. Several placement grooves 9 on the outer side of the arc-shaped seat 3 are used to place the first rotating scraper 4 and the second rotating scraper 6, so as to avoid them occupying the gap between the arc-shaped seat 3 of the door frame 1 and the door panel 2, causing the rotating scraper to get stuck between the door frame 1 and the door panel 2;

[0034] The coal ash inside the placement tank 9, whose structure has been damaged by the sharp teeth 8, will be cleaned away by the wind and the vibration force of the device itself during operation.

[0035] In an optional embodiment, a pointed cone 7 for cleaning coal ash is provided on the outer side of the arc-shaped seat 3. The pointed cone 7 is provided at the cleaning dead corners of several first rotating scrapers 4 and second rotating scrapers 6. As the arc-shaped seat 3 moves, the pointed cone 7 inserts into the interior of the coal ash, thereby destroying its structural integrity. At the same time, a groove for increasing the friction between the pointed cone and the coal ash can be provided on its outer side, or a component with a barbed structure can be provided so that some coal ash is brought out when the door panel 2 is opened. The coal ash stuck at the barbed on the outer side of the door panel 2 will be blown away by the flowing air when the door panel 2 is first opened. Because the airflow at the hot air duct is fixed, a small air duct is formed when the door panel 2 is first opened. At this time, the airflow speed of the hot air is relatively high, thereby blowing away the coal ash stuck at the barbed on the outer side of the door panel 2 so that it can be used again later.

[0036] In an optional embodiment, a sealing surface 10 is provided on the outer side of the arc-shaped seat 3. The sealing surface 10 is set as an inclined surface with an angle between 30° and 45°. At the same time, a matching sealing inclined surface is provided on the inner side of the door frame 1. The sealing surface 10 can increase the sealing performance between the door and the frame and prevent hot air leakage.

[0037] In an optional embodiment, a fixing plate 12 is provided on the outer side of the door panel 2 to scrape away coal ash from the straight groove of the door frame 1. The fixing plate 12 scrapes away the coal ash inside the straight groove as the door panel 2 moves, thus preventing it from affecting the flexibility of the door panel 2's movement.

[0038] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A pneumatic isolation hot air door for a coal mill, comprising a door frame (1) and a door panel (2), the door panel (2) comprising an arc-shaped seat (3); characterized in that: The outer side of the arc-shaped seat (3) is provided with several first rotating scrapers (4) and second rotating scrapers (6) for removing coal ash. The first rotating scrapers (4) and the second rotating scrapers (6) move synchronously. In the initial state, the angles formed by the first rotating scrapers (4) and the second rotating scrapers (6) and the tangent of the arc-shaped seat (3) are α and β, respectively, and the angles of α and β are not greater than 90°.

2. The pneumatic isolation coal mill hot air damper according to claim 1, characterized in that: When the first rotating scraper (4) comes into contact with the inner groove of the door frame (1), the second rotating scraper (6) does not come into contact with the inner groove of the door frame (1).

3. The pneumatic isolation coal mill hot air damper according to claim 1 or 2, characterized in that: A connecting cable (5) is provided on the outer side of the first rotating scraper (4) to pull the second rotating scraper (6) to move synchronously.

4. The pneumatic isolation coal mill hot air damper according to claim 1, characterized in that: The first rotating scraper (4) and the second rotating scraper (6) are provided with sharp teeth (8) on one side for cleaning the coal ash inside the placement trough (9).

5. The pneumatic isolation coal mill hot air damper according to claim 4, characterized in that: The outer side of the arc-shaped seat (3) is provided with a pointed cone (7) for cleaning coal ash.

6. The pneumatic isolation coal mill hot air damper according to claim 1, characterized in that: A sealing surface (10) is provided on the outer side of the arc-shaped seat (3).

7. The pneumatic isolation coal mill hot air damper according to claim 1, characterized in that: A fixing plate (12) is provided on the outside of the door panel (2) to scrape away coal ash at the straight groove of the door frame (1).

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