Long-service-life wear-resistant furnace mouth fixed section flue structure

Abstract

The utility model discloses a long-life wear-resistant furnace mouth fixed section flue structure, which comprises an upper header group, a lower header group and a plurality of groups of heated pipes, each of the upper header group and the lower header group comprises two groups of annular headers which are communicated with each other inside and outside, two ends of each group of heated pipes are respectively communicated with the upper header group and the lower header group on the inner side, and the upper header group and the lower header group are communicated with each other. The upper header group is arranged above the lower header group, the bottom of the heated pipe is bent and extends into the furnace mouth, and an alloy wear-resistant layer is overlaid on the surface of the heated pipe. The flue has the advantages that the abrasion and thinning degree of the flue is reduced by surfacing the alloy abrasion-resistant layer on the surface of the heated pipe, so that the service life of the flue at the fixed section is prolonged, meanwhile, the shutdown time of a converter caused by flue replacement is reduced, continuous and stable production is guaranteed, and the production efficiency is improved. And the safety risk of personnel caused by flue maintenance is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of flue arrangements, and particularly relates to a long-life wear-resistant flue structure for the fixed section of a furnace mouth. Background Art

[0002] During the decarburization blowing process of a converter, a large amount of high-temperature flue gas containing combustible gas is generated. To absorb the heat in the high-temperature flue gas during converter smelting, recover steam, reduce the flue gas discharge temperature, and at the same time create conditions for converter flue gas dust removal and gas recovery, a converter waste heat boiler flue is set up. The waste heat boiler flue consists of a movable hood, a fixed section flue of the furnace mouth, a movable section flue, a middle three-section flue, and a final section flue. The temperature entering the waste heat boiler flue is about 1650 °C, and this heat is generated by the chemical reaction of blowing oxygen into the converter molten iron, and the carbon in the metal separates from the molten iron and burns partially at the lower part of the waste heat boiler flue.

[0003] The fixed section flue of the furnace mouth in the lower part of the waste heat boiler flue is closest to the converter furnace mouth and is in the harshest environment. Affected by the steel smelting process, the temperature in the converter fluctuates constantly, and the temperature in the flue will fluctuate accordingly. With the steep rise and fall of the flue gas temperature, the flue will expand and contract accordingly and is constantly under the action of alternating stress. Under such a harsh working condition environment, any flaw in design, material, production, and use is difficult to withstand such long-term thermal fatigue, and ultimately will lead to leakage and production stoppage or even cause major accidents. In addition, the high-temperature flue gas in the flue also contains a large amount of dust particles, which will cause strong abrasion to the inner wall of the flue during the high-speed movement of the gas flow. Over time, the inner side wall will become thinner until the flue fails and is scrapped. Content of the Utility Model

[0004] The purpose of the utility model is to provide a long-life wear-resistant flue structure for the fixed section of a furnace mouth, which reduces the degree of wear and thinning of the flue by surfacing an alloy wear-resistant layer on the surface of the heating tube, thereby extending the life of the fixed section flue.

[0005] The above technical purpose of the utility model is achieved through the following technical solutions:

[0006] A long-life wear-resistant flue structure for the fixed section of a furnace mouth, characterized in that it includes an upper header group, a lower header group, and heating tubes. Both the upper header group and the lower header group include two sets of annular headers that are internally and externally connected. There are several groups of heating tubes. The two ends of each group of heating tubes are respectively connected to the inner upper header group and the lower header group. The upper header group is arranged above the lower header group. The bottom of the heating tube is bent and extends into the furnace mouth, and an alloy wear-resistant layer is surfaced on the surface of the heating tube.

[0007] Preferably, a plurality of groups of support beams are fixedly connected below the outer annular header of the lower header, and the bottoms of the plurality of groups of support beams are fixedly installed outside the furnace mouth.

[0008] Preferably, the plurality of heating tubes are arranged in a circular array in the furnace mouth. After being bent in the furnace mouth at the bottom of each group of heating tubes, an inner tube portion and an outer tube portion are formed. An outlet is arranged above the outer tube portion and is communicated with the annular header inside the upper header group. An inlet is arranged above the inner tube portion and is communicated with the annular header inside the lower header group.

[0009] Preferably, rock wool is filled between the inner tube portion and the outer tube portion, and a flue gas cover plate is installed above the rock wool. The flue gas cover plate is horizontally installed between the lower header group and the inner tube portion.

[0010] Preferably, two groups of reinforcing rings are arranged above the furnace mouth of the outer tube portion, namely a first reinforcing ring and a second reinforcing ring. The first reinforcing ring is arranged outside the outer tube portion, and the second reinforcing ring is arranged inside the outer tube portion.

[0011] Preferably, positioning pins are vertically and fixedly installed between the inner and outer annular headers of the upper header group.

[0012] Preferably, a sand seal groove is arranged above the upper header group.

[0013] Preferably, the heating tubes are made of 15CrMoG alloy steel. A total of 228 heating tubes are provided and numbered in sequence. Alloy wear-resistant layers are surfacing-welded on the surfaces of the heating tubes numbered 1-38 and 191-228 within the 120-degree range in front of the furnace mouth.

[0014] Preferably, the alloy wear-resistant layer is formed by surfacing-welding with ERNiCrMo-3 nickel-based alloy welding wire. The surfacing range of the alloy wear-resistant layer is within 140 degrees of the inner surface of the heating tube. The thickness of the alloy wear-resistant layer is 3 mm, and the surfacing height is 3 m.

[0015] Preferably, the adjacent inner tube portion and outer tube portion are formed by butt-welding after being arranged with flat steel side by side. The connection of the flat steel between the inner tube portions is close to the center of the inner tube portion, and the connection of the flat steel between the inner tube portions is close to the inner side of the furnace mouth.

[0016] In summary, the present utility model has the following beneficial effects: By surfacing alloy wear-resistant layers on the surfaces of the heating tubes within the 120-degree range in front of the furnace mouth, the present utility model reduces the degree of wear and thinning of the flue, thereby extending the service life of the fixed-section flue. At the same time, the extension of the service life of the flue also reduces the converter downtime caused by replacing the flue, ensures the continuity and stability of production, and reduces the safety risks brought by personnel for flue maintenance. Description of the Drawings

[0017] Figure 1 is the front main body schematic diagram of the present utility model;

[0018] Figure 2 is the schematic diagram of the specific connection structure of the heating tubes of the present utility model;

[0019] Figure 3 is Figure 2 the schematic diagram of the structure at the A-A line in

[0020] Figure 4 is the schematic diagram of the distribution of the heating tubes of the present utility model;

[0021] Figure 5 is Figure 4 the partial enlarged schematic diagram of the I area in

[0022] In the figure, 1. lower header group, 2. upper header group, 3. heating tube, 4. flat steel, 5. alloy wear-resistant layer, 6. flue gas cover plate, 7. first reinforcing ring, 8. second reinforcing ring, 9. rock wool, 10. support beam, 11. positioning pin, 12. sand seal groove. Specific embodiments

[0023] The following further describes the specific embodiments of the present utility model in conjunction with the accompanying drawings. This embodiment does not constitute a limitation to the present utility model.

[0024] As Figures 1 to 5 shown, a long-life wear-resistant furnace mouth fixed-section flue structure includes an upper header group 2, a lower header group 1 and heating tubes 3. Both the upper header group 2 and the lower header group 1 include two groups of annular headers that are internally and externally connected. A number of groups of heating tubes 3 are provided to form a membrane wall tube row. Both ends of each group of heating tubes 3 are respectively connected to the inner upper header group 2 and the lower header group 1. The upper header group 2 is arranged above the lower header group 1. The bottom of the heating tubes 3 is bent and extends into the furnace mouth. An alloy wear-resistant layer 5 is surfacing-welded on the surface of the heating tubes 3.

[0025] A number of groups of support beams 10 are also fixedly connected below the outer annular header of the lower header, and the bottoms of the number of groups of support beams 10 are fixedly installed on the outside of the furnace mouth.

[0026] A number of groups of heating tubes 3 are arranged in a circular array in the furnace mouth. The bottom of each group of heating tubes 3 forms an inner tube part 13 and an outer tube part 14 after being bent in the furnace mouth. A water outlet is arranged above the outer tube part 14 and is connected to the inner annular header of the upper header group 2. An inlet is arranged above the inner tube part 13 and is connected to the inner annular header of the lower header group 1. After the cooling water enters the lower header group 1, it is evenly distributed to each heating tube 3 of the membrane wall tube row. Each heating tube 3 is an independent loop, and the cooling water enters the upper header group 2 through the heating tubes 3 to form a cycle.

[0027] Rock wool 9 is filled between the inner pipe section 13 and the outer pipe section 14. The rock wool 9 mainly functions as fireproofing, heat insulation, and thermal insulation. A flue cover plate 6 is installed above the rock wool 9. The flue cover plate 6 is horizontally installed between the lower header group 1 and the inner pipe section 13, and the flue cover plate 6 can prevent the leakage of rock wool.

[0028] Two sets of reinforcing rings are provided above the furnace mouth on the outer pipe section 14, namely the first reinforcing ring 7 and the second reinforcing ring 8. The first reinforcing ring 7 is arranged outside the outer pipe section 14, and the second reinforcing ring 8 is arranged inside the outer pipe section 14. The first reinforcing ring 7 and the second reinforcing ring 8 can withstand the deformation of the heating pipe 3.

[0029] A positioning pin 11 is also vertically and fixedly installed between the inner and outer annular headers of the upper header group 2 to ensure the correct and precise relative position of the fixed-section flue.

[0030] A sand seal groove 12 is provided above the upper header group 2 to prevent the leakage of flue gas by sealing.

[0031] The heating pipe 3 is made of 15CrMoG alloy steel. There are a total of 228 heating pipes 3, which are numbered in sequence. Alloy wear-resistant layers 5 are surfacing-welded on the surfaces of the heating pipes 3 numbered 1 - 38 and 191 - 228 within the 120-degree range in front of the furnace mouth.

[0032] The alloy wear-resistant layer 5 is formed by surfacing-welding with ERNiCrMo-3 nickel-based alloy welding wire. The surfacing range of the alloy wear-resistant layer 5 is within 140 degrees of the inner surface of the heating pipe 3. The thickness of the alloy wear-resistant layer 5 is 3 mm, and the surfacing height is 3 m.

[0033] The adjacent inner pipe section 13 and the outer pipe section 14 are formed by butt welding after being arranged side by side with flat steel 4. The connection of the flat steel 4 between the inner pipe sections 13 is close to the center of the inner pipe section 13, and the connection of the flat steel 4 between the inner pipe sections 13 is close to the inner side of the furnace mouth.

[0034] By surfacing alloy wear-resistant layers on the surfaces of the heating pipes within the 120-degree range in front of the furnace mouth, the present utility model reduces the degree of wear and thinning of the flue, thereby extending the service life of the fixed-section flue. At the same time, the extension of the service life of the flue also reduces the converter downtime caused by replacing the flue, ensures the continuity and stability of production, and reduces the safety risks for personnel during flue maintenance. The above is only a preferred embodiment of the present utility model and is not used to limit the present utility model. Those skilled in the art can make various modifications or equivalent replacements within the essence and protection scope of the present utility model, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the technical solution of the present utility model.

Claims

1. A long-life wear-resistant furnace mouth fixed-section flue structure, characterized in that, It includes an upper header group, a lower header group and heating tubes. Both the upper header group and the lower header group include two sets of annular headers that are internally and externally connected. There are several groups of heating tubes. Each group of heating tubes is connected to the inner upper header group and lower header group at both ends. The upper header group is arranged above the lower header group. The bottom of the heating tube is bent and extends into the furnace mouth. An alloy wear-resistant layer is surfacing-welded on the surface of the heating tube.

2. The long-life wear-resistant furnace mouth fixed-section flue structure according to claim 1, characterized in that: Several support beams are also fixedly connected below the outer annular header of the lower header. The bottoms of several groups of support beams are fixedly installed outside the furnace mouth.

3. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 1, characterized in that: Several groups of heating tubes are arranged in a circular array in the furnace mouth. The bottom of each group of heating tubes forms an inner tube part and an outer tube part after being bent in the furnace mouth. An outlet is arranged above the outer tube part and is connected to the annular header inside the upper header group. An inlet is arranged above the inner tube part and is connected to the annular header inside the lower header group.

4. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 3, characterized in that: Rock wool is filled between the inner tube part and the outer tube part. A flue cover plate is installed above the rock wool. The flue cover plate is horizontally installed between the lower header group and the inner tube part.

5. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 3, characterized in that: Two reinforcing rings, namely a first reinforcing ring and a second reinforcing ring, are arranged above the furnace mouth of the outer tube part. The first reinforcing ring is arranged outside the outer tube part, and the second reinforcing ring is arranged inside the outer tube part.

6. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 1, characterized in that: Positioning pins are also vertically and fixedly installed between the inner and outer annular headers of the upper header group.

7. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 1, characterized in that: A sand seal groove is arranged above the upper header group.

8. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 1, characterized in that: The heating tubes are made of 15CrMoG alloy steel. There are 228 heating tubes in total, which are numbered in sequence. The alloy wear-resistant layer is surfacing-welded on the surfaces of the heating tubes numbered 1-38 and 191-228 within the 120-degree range in front of the furnace mouth.

9. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 8, characterized in that: The alloy wear-resistant layer is formed by surfacing-welding with ERNiCrMo-3 nickel-based alloy welding wire. The surfacing range of the alloy wear-resistant layer is within 140 degrees of the inner surface of the heating tube. The thickness of the alloy wear-resistant layer is 3 mm, and the surfacing height is 3 m.

10. A long-life wear-resistant furnace mouth fixed-section flue structure according to claim 3, characterized in that: The adjacent inner tube part and outer tube part are formed by butt-welding flat steel and then fusion-welding. The connection of the flat steel between the inner tube parts is close to the center of the inner tube part, and the connection of the flat steel between the inner tube parts is close to the inner side of the furnace mouth.

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