A boiler annular wind box structure and sealing method

Abstract

The present invention discloses a boiler annular bellows structure, the technical solution of which is as follows: it includes a burner, a furnace and a furnace pipe arranged around the furnace, and also includes an annular bellows and a band. The annular bellows is arranged around the outside of the furnace pipe, the band is fixed between the furnace pipe and the annular bellows, the furnace pipes are stacked and arranged on the inner wall of the band to form a furnace pipe wall, the burner is arranged through the furnace pipe wall, a first flexible cushion layer is provided between adjacent furnace pipes, a second flexible cushion layer is provided on the side of the furnace pipe close to the annular bellows, the second flexible cushion layer extends to the outer wall of the band, the edge of the annular bellows is connected to the furnace pipe to form an annular sealing channel, and the annular sealing channel is respectively connected to the air supply pipeline and the air inlet of the burner. The boiler annular bellows structure of the present invention can effectively avoid the leakage problem of high-temperature dust and improve the factory environment. The present invention also provides a sealing method for the boiler annular bellows structure.

Description

Technical Field

[0001] The invention relates to the technical field of boiler structures, and in particular to a boiler annular bellows structure and a sealing method for the boiler annular bellows structure. Background Art

[0002] Conventional boilers mainly include a furnace for combustion and heating and furnace tubes arranged around the furnace. The furnace tubes are stacked and arranged on a vertical support plate to form a furnace tube wall. One end of the burner passes through the furnace tube wall and enters the furnace, and the other end is connected to the external fresh air supply pipeline. There is also an air inlet in the middle of the burner, which is connected to the air supply pipeline.

[0003] One end of the air preheater is set at the air outlet of the furnace, and the other end is set on the air supply pipe. As a heat exchange device, the purpose of the air preheater is to realize the recycling of the heat of the exhaust in the furnace air outlet pipe. Specifically, the gas in the air supply pipe forms secondary air after circulating heat exchange in the air preheater. The secondary air enters the burner through the air inlet and finally enters the furnace through the burner to mix with the fuel in the fresh air supply pipe for combustion, which improves the heat utilization efficiency while achieving heating of the furnace tube.

[0004] However, the gas in the air outlet pipe contains a large amount of high-temperature dust generated after combustion. In the air preheater, when the air outlet pipe and the gas in the air supply pipe are exchanging heat, high-temperature dust will enter the air supply pipe. Since the temperature variation range of the furnace tube wall is large, there must be thermal alternating stress between the furnace tube and the support plate and the burner, which makes it easy for gaps to appear. Considering that the dust temperature in the furnace is extremely high, if it leaks from the gap, it will seriously affect the environment of the boiler room area. For example, during the maintenance of the fan, it was found that the sliding bearing was severely worn, affecting the safe operation of the unit. After analysis, it was directly related to the poor operating environment of the fan caused by the leakage of boiler ash. In addition, due to the high-temperature ash accumulation falling in pieces, there is also a certain risk of high-temperature burns. Summary of the invention

[0005] The purpose of the present invention is to solve the problem in the prior art that gaps are easily present in the boiler structure, resulting in leakage of high-temperature dust that affects the factory environment and operation safety.

[0006] The technical solution of the present invention is: to provide a boiler annular bellows structure, including a burner, a furnace and a furnace pipe arranged around the furnace, and also including an annular bellows and a binding band, the annular bellows is arranged around the outside of the furnace pipe, the binding band is fixed between the furnace pipe and the annular bellows, the binding band includes an inner wall facing the furnace and an outer wall sealed with the annular bellows, the furnace pipes are stacked and arranged on the inner wall of the binding band to form a furnace pipe wall, the burner is arranged through the furnace pipe wall, a first flexible pad is provided between adjacent furnace pipes, a second flexible pad is provided on the side of the furnace pipe close to the annular bellows, the second flexible pad extends to the outer wall of the binding band, the edge of the annular bellows is connected to the furnace pipe to form an annular sealing channel, and the annular sealing channel is respectively connected to the gas supply pipe and the air inlet of the burner.

[0007] The beneficial effects of the present invention compared with the prior art are as follows: by arranging an annular bellows on the outside of the furnace tube, an annular sealed channel is formed between the annular bellows and the furnace tube wall, and the secondary air heated in the air supply duct enters the annular sealed channel to achieve the heat preservation effect on the furnace chamber; at the same time, through the arrangement of the first flexible pad layer and the second flexible pad layer, due to the flexible seal, the furnace tube itself and the gap between the binding band and the furnace tube can be effectively and durably sealed, which effectively improves the sealing of the annular sealed channel and avoids the leakage of high-temperature dust in the annular sealed channel.

[0008] Preferably, the binding is in the shape of a column, there are multiple bindings arranged around the furnace, and the furnace pipe is fixed to a single edge of the inner wall of the binding. Due to the existence of thermal alternating stress, the method of directly welding the furnace pipe and the support plate in the prior art is prone to bulging and cracking. Therefore, by setting the binding, the furnace pipe and the multiple bindings are all single-point welded, which effectively avoids this problem.

[0009] Preferably, the furnace tube is tilted, and the angle between the furnace tube and the horizontal plane is 15-30°, which is beneficial to the thermal circulation of water in the furnace tube.

[0010] Preferably, fins for heat conduction are provided between the furnace tubes, and the fins are connected with filling blocks near the edge of the annular bellows. The edge of the annular bellows is welded to the filling blocks, furnace tubes and outer side walls of the binding bands to achieve sealing.

[0011] Preferably, a positioning column is fixed on the furnace tube, the end of the positioning column passes through the second flexible cushion layer, and a mesh cover is provided on the outer surface of the second flexible cushion layer, and the mesh cover is connected to the end of the positioning column. Since the secondary air in the annular sealed channel is mixed with high-temperature dust, the provision of the mesh cover can effectively protect the second flexible cushion layer and reduce the wear or deformation of the second flexible cushion layer.

[0012] Preferably, the second flexible cushion layer includes an inner cushion layer and an outer cushion layer, the inner cushion layer covers the intersection of the left side wall of the binding band and the furnace tube and the intersection of the right side wall of the binding band and the furnace tube, and the outer cushion layer covers the outer side wall of the binding band, the inner cushion layer, and a side wall of the furnace tube close to the furnace chamber. The second flexible cushion layer effectively blocks the gap between the binding band and the furnace tube, preventing leakage of high-temperature dust.

[0013] Preferably, the distances between the left side and the right side of the outer cushion layer and the binding belt are both greater than 0.3 m to ensure a more stable sealing effect.

[0014] Preferably, the first flexible cushion layer and the second flexible cushion layer are both thermal insulation cotton, and the first flexible cushion layer is glued to the tube wall of the furnace tube. The use temperature of the thermal insulation cotton can reach 450°C, and it has good durability and can better block the gap.

[0015] The present invention also provides a sealing method for a boiler annular wind box structure, which specifically comprises the following steps:

[0016] S1, clean the annular bellows, binding belts and furnace tubes, and confirm that the connections between the annular bellows, binding belts and furnace tubes meet the requirements;

[0017] S2, welding a positioning column on the side wall of the furnace tube close to the annular bellows, and the positioning column is arranged toward the annular bellows;

[0018] S3, filling a first flexible cushion layer between the furnace tubes, and attaching the first flexible cushion layer to the tube wall of the furnace tube by an adhesive;

[0019] S4, covering the side wall of the furnace tube close to the annular wind box with a second flexible cushion layer, the second flexible cushion layer extends to and covers the outer side wall of the binding belt, and the end of the positioning column passes through the second flexible cushion layer;

[0020] S5, covering the outer surface of the second flexible cushion layer with a mesh cover and compacting it, and then fixing the end of the positioning column to the mesh cover through a gasket or a thrust plate.

[0021] Preferably, the method further comprises step S6 of further gluing the gaps between the second flexible cushion layer and the binding belt and the furnace tube by means of an adhesive. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a boiler annular wind box structure of the present invention;

[0023] Figure 2 A top view of a boiler annular wind box structure of the present invention;

[0024] Figure 3 for Figure 2 A magnified schematic diagram of the middle A area;

[0025] Figure 4 A side view schematic diagram of a boiler annular wind box structure of the present invention;

[0026] Figure 5 For along Figure 4 Schematic cross-sectional view of the BB section line.

[0027] In the attached drawings: 1-furnace; 2-furnace tube; 2.1-filling block; 3-annular bellows; 4-binding strap; 4.1-welding point; 5-burner; 5.1-air inlet; 6-first flexible cushion layer; 7-second flexible cushion layer; 7.1-inner cushion layer; 7.2-outer cushion layer; 7.3-positioning column; 7.4-mesh cover; 8-air preheater; 8.1-air outlet pipe; 8.2-air supply pipe; 8.3-fresh air supply pipe. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] See also Figure 1 and Figure 2 A boiler annular wind box structure of the present invention comprises a furnace 1, a furnace tube 2 arranged around the furnace 1, an annular wind box 3 arranged around the outer side of the furnace tube 2, and a band 4 fixed relative to the ground. The middle part of the band 4 is located between the furnace tube 2 and the annular wind box 3. The side of the band 4 facing the furnace 1 is the inner wall, and the side facing away from the furnace 1 is the outer wall, and the outer wall of the band 4 is sealed and welded to the upper edge and the lower edge of the annular wind box 3. The furnace tubes 2 are stacked and arranged on the inner wall of the band 4 to form a furnace tube wall, one end of the burner 5 passes through the furnace tube wall to enter the furnace 1, and the other end is connected to the fresh air supply pipeline 8.3. The air inlet 5.1 of the burner 5 is located between the furnace tube wall and the annular wind box 3. A first flexible cushion layer 6 is provided between adjacent furnace tubes 2, and a second flexible cushion layer 7 is provided on the side wall of the furnace tube 2 close to the annular wind box 3, and the second flexible cushion layer 7 extends and covers the outer wall of the band 4. The edge of the annular wind box 3 is welded to the side wall of the furnace tube 2, so that an annular sealed channel is formed between the annular wind box 3 and the furnace tube wall. The annular sealed channel is connected to the air supply pipeline 8.2 and the air inlet 5.1 of the burner 5 respectively.

[0030] When in use, the furnace 1 discharges high-temperature exhaust gas through the air outlet pipe 8.1, and the air preheater 8 transfers the heat of the high-temperature exhaust gas in the air outlet pipe 8.1 to the air supply pipe 8.2. The heated secondary air in the air supply pipe 8.2 first enters the annular sealing channel to achieve the heat preservation effect on the furnace 1; then the secondary air enters the burner 5 through the air inlet 5.1 of the burner 5, and mixes with the fuel in the fresh air supply pipe 8.3 and enters the furnace 1 for combustion to achieve heating of the furnace tube 2; the high-temperature exhaust gas after combustion is discharged from the air outlet pipe 8.1 and heat is exchanged again at the air preheater 8, thereby realizing the recycling of heat. At the same time, due to the flexible sealing of the first flexible cushion layer 6 between the furnace tubes 2, the gap between the furnace tubes 2 is blocked; the second flexible cushion layer 7 is flexibly sealed between the bandage 4 and the furnace tube 2, and the gap between the bandage 4 and the furnace tube 2 is blocked, thereby effectively improving the sealing of the annular sealing channel and avoiding the leakage of high-temperature dust.

[0031] See also Figure 2 In this embodiment, the binding band 4 is columnar, and four binding bands 4 are arranged around the furnace 1 to achieve stable support for the furnace tube 2. The single-side edge of the inner wall of the binding band 4 is provided with a plurality of welding points 4.1 arranged in the vertical direction, and the furnace tube 2 is fixed to the binding band 4 by welding through the welding points 4.1, thereby effectively avoiding the problem of expansion and cracking between the furnace tube 2 and the support plate due to thermal alternating stress in the prior art. At the same time, considering that there is a gap between the edge of the inner wall of the binding band 4 without the welding point 4.1 and the furnace tube 2, the second flexible cushion layer 7 is provided to effectively block the gap and ensure the sealing of the annular sealing channel.

[0032] It should be noted that the binding bands 4 can also be set to other numbers and evenly spaced to achieve stable support for the furnace tubes 2; the burner 5 is located between the binding bands 4 and passes through the gaps between adjacent furnace tubes 2 into the furnace 1 to avoid interference.

[0033] See also Figure 4 and Figure 5 A horizontal positioning column 7.3 is fixedly welded to the side wall of the furnace tube 2 near the annular wind box 3, and the end of the positioning column 7.3 passes through the second flexible cushion layer 7. A mesh cover 7.4 is provided on the outer surface of the second flexible cushion layer 7, and the mesh cover 7.4 and the end of the positioning column 7.3 are connected to each other through a gasket or a thrust plate. Since the secondary air in the annular sealing channel is mixed with high-temperature dust, the setting of the mesh cover 7.4 can effectively protect the second flexible cushion layer 7 and reduce the wear or deformation of the second flexible cushion layer 7.

[0034] In this embodiment, the second flexible cushion layer 7 includes an inner cushion layer 7.1 and an outer cushion layer 7.2. The inner cushion layer 7.1 covers the intersection of the left wall of the band 4 and the furnace tube 2 and the intersection of the right wall of the band 4 and the furnace tube 2. The outer cushion layer 7.2 covers the outer wall of the band 4, the inner cushion layer 7.1, and the side wall of the furnace tube 2 close to the furnace 1. Considering that high-temperature dust can only pass through the gap between the band 4 and the furnace tube 2 near the upper edge or lower edge of the annular bellows 3, the second flexible cushion layer 7 can be only arranged at the upper edge and lower edge of the annular bellows 3. Of course, it can also be arranged so that the second flexible cushion layer 7 completely covers the band 4 in the annular bellows 3. The setting of the second flexible cushion layer 7 blocks the gap between the band 4 and the furnace tube 2, effectively preventing the leakage of high-temperature dust. The distance between the left and right sides of the outer cushion layer 7.2 relative to the band 4 is greater than 0.3m to ensure a more stable blocking effect. It should be noted that the positioning column 7.3 can only pass through the outer cushion layer 7.2 to fix the second flexible cushion layer 7; it can also pass through the outer cushion layer 7.2 and the inner cushion layer 7.1 at the same time, so as to fix the second flexible cushion layer 7 while making the connection between the outer cushion layer 7.2 and the inner cushion layer 7.1 more stable.

[0035] See also Figure 5 The furnace tube 2 is tilted, and the angle between the furnace tube 2 and the horizontal plane is 20°, which is conducive to the heat circulation of water in the furnace tube 2. Fins (not shown in the figure) for heat conduction are also arranged between adjacent furnace tubes 2. The fins are connected to the position near the edge of the annular bellows 3 with a filling block 2.1. The upper edge and the lower edge of the annular bellows 3 are welded to the filling block 2.1, the furnace tube 2, and the outer wall of the binding band 4 in turn to achieve sealing.

[0036] The first flexible cushion layer 6 and the second flexible cushion layer 7 are both thermal insulation cotton, and the first flexible cushion layer 6 is glued to the tube wall of the furnace tube 2. The use temperature of the thermal insulation cotton can reach 450°C, and it has good durability and can better block the gap.

[0037] The present invention also provides a sealing method for a boiler annular wind box structure, which specifically comprises the following steps:

[0038] S1, clean the annular bellows 3, the binding belt 4, and the furnace tube 2, and confirm that the connection between the annular bellows 3, the binding belt 4, and the furnace tube 2 meets the requirements;

[0039] S2, welding a positioning column 7.3 on the side wall of the furnace tube 2 close to the annular wind box 3, and the positioning column 7.3 is arranged toward the annular wind box 3;

[0040] S3, filling the first flexible cushion layer 6 between the furnace tubes 2, and making the first flexible cushion layer 6 adhere to the tube wall of the furnace tube 2 by adhesive;

[0041] S4, a second flexible cushion layer 7 is covered on the side wall of the furnace tube 2 close to the annular wind box 3, the second flexible cushion layer 7 extends to and covers the outer side wall of the binding belt 4, and the end of the positioning column 7.3 passes through the second flexible cushion layer 7;

[0042] S5, cover the outer surface of the second flexible cushion layer 7 with the mesh cover 7.4 and compact it, and then fix the end of the positioning column 7.3 to the mesh cover 7.4 through a gasket or a thrust plate.

[0043] Furthermore, after step S5, the gaps between the second flexible cushion layer 7 and the binding belt 4 and the furnace tube 2 may be glued by adhesive to further improve the sealing performance of the annular sealing channel.

[0044] The present invention is described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A boiler annular wind box structure, comprising a burner (5), a furnace (1) and a furnace tube (2) arranged around the furnace (1), characterized in that: The invention also comprises an annular bellows (3) and a binding belt (4), wherein the annular bellows (3) is arranged around the outer side of the furnace tube (2), the binding belt (4) is fixed between the furnace tube (2) and the annular bellows (3), the binding belt (4) comprises an inner side wall facing the furnace chamber (1) and an outer side wall sealed to the annular bellows (3), the furnace tubes (2) are stacked and arranged on the inner side wall of the binding belt (4) to form a furnace tube wall, the burner (5) is arranged through the furnace tube wall, a first flexible cushion layer (6) is arranged between adjacent furnace tubes (2), a second flexible cushion layer (7) is arranged on the side of the furnace tube (2) close to the annular bellows (3), the second flexible cushion layer (7) extends to the outer side wall of the binding belt (4), the edge of the annular bellows (3) is connected to the furnace tube (2) to form an annular sealed channel, and the annular sealed channel is respectively connected to the air supply pipeline (8.2) and the air inlet (5.1) of the burner (5).

2. A boiler annular wind box structure according to claim 1, characterized in that: The binding band (4) is in the shape of a column, there are a plurality of binding bands (4) arranged around the furnace (1), and the furnace tube (2) is fixed to a single side edge of the inner wall of the binding band (4).

3. A boiler annular wind box structure according to claim 2, characterized in that: The furnace tube (2) is arranged tilted, and the angle between the furnace tube (2) and the horizontal plane is 15-30°.

4. A boiler annular wind box structure according to claim 3, characterized in that: Fins for heat conduction are also provided between the furnace tubes (2); a filling block (2.1) is connected to the fin near the edge of the annular bellows (3); the edge of the annular bellows (3) is welded to the filling block (2.1), the furnace tubes (2), and the outer side wall of the binding band (4) to achieve sealing.

5. A boiler annular wind box structure according to any one of claims 1 to 4, characterized in that: A positioning column (7.3) is fixed on the furnace tube (2), the end of the positioning column (7.3) passes through the second flexible cushion layer (7), the outer surface of the second flexible cushion layer (7) is provided with a mesh cover (7.4), and the mesh cover (7.4) is connected to the end of the positioning column (7.3).

6. A boiler annular wind box structure according to claim 5, characterized in that: The second flexible cushion layer (7) comprises an inner cushion layer (7.1) and an outer cushion layer (7.2); the inner cushion layer (7.1) covers the intersection between the left side wall of the binding band (4) and the furnace tube (2) and the intersection between the right side wall of the binding band (4) and the furnace tube (2); and the outer cushion layer (7.2) simultaneously covers the outer side wall of the binding band (4), the inner cushion layer (7.1), and a side wall of the furnace tube (2) close to the furnace chamber (1).

7. A boiler annular wind box structure according to claim 6, characterized in that: The distances between the left side and the right side of the outer cushion layer (7.2) and the binding belt (4) are both greater than 0.3 m.

8. The boiler annular wind box structure according to claim 5, characterized in that: The first flexible cushion layer (6) and the second flexible cushion layer (7) are both thermal insulation cotton, and the first flexible cushion layer (6) is glued to the tube wall of the furnace tube (2).

9. A sealing method for a boiler annular wind box structure, characterized in that: The boiler annular wind box structure according to any one of claims 5 to 8 is applied, and includes the following steps: S1, cleaning the annular bellows (3), the binding belt (4), and the furnace tube (2), and confirming that the connection between the annular bellows (3), the binding belt (4), and the furnace tube (2) meets the requirements; S2, welding a positioning column (7.3) on the side wall of the furnace tube (2) close to the annular wind box (3), and the positioning column (7.3) is arranged toward the annular wind box (3); S3, filling a first flexible cushion layer (6) between the furnace tubes (2), and attaching the first flexible cushion layer (6) to the tube wall of the furnace tube (2) by means of an adhesive; S4, a second flexible cushion layer (7) is covered on the side wall of the furnace tube (2) close to the annular wind box (3), the second flexible cushion layer (7) extends to and covers the outer side wall of the binding belt (4), and the end of the positioning column (7.3) passes through the second flexible cushion layer (7); S5, the mesh cover (7.4) is covered on the outer surface of the second flexible cushion layer (7) and compacted, and then the end of the positioning column (7.3) is fixed to the mesh cover (7.4) by a gasket or a thrust plate.

10. The sealing method of a boiler annular wind box structure according to claim 9, characterized in that: The method further comprises step S6 of further gluing the gaps between the second flexible cushion layer (7) and the binding belt (4) and the furnace tube (2) using an adhesive.

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