Cooling system structure for heating mantle of bell-type annealing furnace

Abstract

The utility model relates to the technical field of annealing furnace equipment, in particular to a cooling system structure for a heating mantle of a bell-type annealing furnace. A bypass pipe which does not pass through a heat exchanger is additionally arranged in the middle of a cold air pipe entering the heat exchanger and is merged into a hot air distribution ring pipe, so that part of cold combustion air is directly blown into the furnace through a burner, and the cooling rate of the bell-type annealing furnace can be improved; by arranging the cooling fan and the cooling air pipe on the outer wall of the heating cover, cold air can be directly blown into the annealing furnace, so that the maximum cooling rate of the annealing furnace is further improved, the annealing time is effectively shortened, and the yield of a unit is increased; the cover type annealing furnace is compact in overall structure, does not need to occupy extra installation space by refitting an existing cover type annealing furnace, and is convenient to use and maintain in the later period.

Description

Technical Field

[0001] The utility model belongs to the technical field of annealing furnace equipment, and in particular relates to a heating hood cooling system structure of a hood-type annealing furnace. Background Art

[0002] Hood annealing furnace is generally used for hot rolling of stainless steel coils. Its heating medium is generally gas fuel, such as natural gas or coke oven gas. The combustion air is directly drawn from the hood annealing furnace workshop by the combustion fan of the heating hood and enters the burner after heat exchange with the high-temperature flue gas generated by combustion.

[0003] Large gas heating hoods are generally arranged with two rows of burners, namely the lower burner and the upper burner. The high-temperature flue gas generated after combustion enters the heat exchanger through the exhaust pipe. The heat exchanger uses the high-temperature flue gas to preheat the cold combustion air and reduce the flue gas temperature before discharging it from above the heating hood.

[0004] The cooling scheme of the hood annealing furnace in the prior art is to use a heating hood combustion-supporting blower to blow the combustion-supporting air into the furnace through the burner for cooling. Since the combustion-supporting air has undergone a first-level heat exchange in the heat exchanger and the maximum flow rate of the combustion-supporting air is limited, the cooling rate of the annealing furnace is low, making it difficult to meet the maximum cooling rate requirements of the process, and the annealing time is extended due to the equipment capacity, affecting the production capacity of the unit. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide a hood cooling system structure of a hood-type annealing furnace, which has a compact overall structure, saves installation space, is easy to use and maintain, can effectively improve the cooling rate of the annealing furnace, and thus reduce the time required for the annealing process.

[0006] The technical solution adopted by the utility model to solve the above technical problems is:

[0007] A hood cooling system structure of a hood of a hood-type annealing furnace comprises an annealing furnace 1 and a heating hood 2, wherein a heat exchanger 3 and a combustion-supporting fan 4 are installed on the upper part of the outer wall of the heating hood 2, wherein the smoke inlet of the heat exchanger 3 is connected to the smoke outlet of the annealing furnace 1 through a smoke exhaust pipe 22, and the combustion-supporting fan 4 is connected to the cold air inlet of the heat exchanger 3 through a cold air pipe 7 entering the heat exchanger, and the hot air outlet of the heat exchanger 3 is connected to a hot air distribution ring pipe 8 installed in the middle part of the outer wall of the heating hood 2 through a hot air pipe 13 exiting the heat exchanger, and the hot air distribution ring pipe 8 is connected to the air inlets of corresponding burners through a plurality of burner hot air pipes;

[0008] A gas distribution ring pipe 16 is installed at the lower part of the outer wall of the heating cover 2, and the gas distribution ring pipe 16 is connected to the gas source through the gas main pipe 14 and the gas joint 11 in sequence, and the gas distribution ring pipe 16 is connected to the gas inlet of the corresponding burner through multiple burner gas pipes;

[0009] The middle part of the cold air pipe 7 entering the heat exchanger is connected to the hot air distribution loop pipe 8 through a bypass pipe 27, and an opening regulating valve 24 is installed on the bypass pipe 27;

[0010] On the upper part of the outer wall of the heating hood 2, on the side far from the heat exchanger 3, a cooling fan 25 is installed, and the cooling fan 25 is directly connected to the cold air inlet of the annealing furnace 1 through a cooling air pipe 26.

[0011] Preferably, there are two upper and lower rows of burners on the lower part of the outer wall of the heating hood 2, with six burners in each row, and the upper burners 20 and the lower burners 21 are arranged staggeredly.

[0012] Preferably, the air inlets of the upper burners 20 are all connected to the hot air distribution loop pipe 8 through the corresponding upper burner hot air pipes 9; the gas inlets of the upper burners 20 are all connected to the gas distribution loop pipe 16 through the corresponding upper burner gas pipes 19.

[0013] Preferably, the air inlets of the lower burners 21 are all connected to the hot air distribution loop pipe 8 through the corresponding lower burner hot air pipes 10; the gas inlets of the lower burners 21 are all connected to the gas distribution loop pipe 16 through the corresponding lower burner gas pipes 17.

[0014] Preferably, an air cut-off valve 6 and an air regulating valve 5 are sequentially installed on the cold air pipe 7 entering the heat exchanger, and the bypass pipe 27 is connected to the pipe section of the cold air pipe 7 entering the heat exchanger between the air cut-off valve 6 and the air regulating valve 5.

[0015] Preferably, a gas cut-off valve 12 and a gas regulating valve 15 are sequentially installed on the main gas pipe 14. One end of the main gas pipe 14 is connected to a gas source through the gas joint 11, and the other end is connected to the gas distribution loop pipe 16.

[0016] Preferably, hot air flow regulating valves 23 are installed on both the upper burner hot air pipes 9 and the lower burner hot air pipes 10.

[0017] Preferably, gas flow regulating valves 18 are installed on both the upper burner gas pipes 19 and the lower burner gas pipes 17.

[0018] The present utility model has the following main advantages compared with the prior art:

[0019] 1. The present utility model provides a cooling system structure for the heating hood of a bell-type annealing furnace. By adding a bypass pipe that does not pass through the heat exchanger in the middle of the cold air pipe entering the heat exchanger and incorporating it into the hot air distribution loop pipe, part of the cold combustion-supporting air can be directly blown into the furnace through the burners, thereby improving the cooling rate of the bell-type annealing furnace;

[0020] 2. By arranging a cooling fan and a cooling air duct on the outer wall of the heating hood, the utility model can directly blow cold air into the annealing furnace, so as to further increase the maximum cooling rate of the annealing furnace, effectively shorten the annealing time, and improve the output of the unit.

[0021] 3. The overall structure of the utility model is compact. By modifying the existing bell-type annealing furnace, it does not need to occupy additional installation space, and is convenient to use and easy to maintain in the later stage. Description of the Drawings

[0022] Figure 1 It is the front view of the cooling system of the heating hood of the bell-type annealing furnace in the embodiment of the utility model;

[0023] Figure 2 It is the side view of the cooling system of the heating hood of the bell-type annealing furnace in the embodiment of the utility model;

[0024] Figure 3 It is the rear view of the cooling system of the heating hood of the bell-type annealing furnace in the embodiment of the utility model.

[0025] In the figure: 1. Annealing furnace; 2. Heating hood; 3. Heat exchanger; 4. Combustion-supporting fan; 5. Air regulating valve; 6. Air cut-off valve; 7. Cold air duct entering the heat exchanger; 8. Hot air distribution ring pipe; 9. Hot air duct of upper burners (No. 7 - 12 burners); 10. Hot air duct of lower burners (No. 1 - 6 burners); 11. Gas joint; 12. Gas cut-off valve; 13. Hot air duct leaving the heat exchanger; 14. Gas main pipe; 15. Gas regulating valve; 16. Gas distribution ring pipe; 17. Gas pipe of lower burners; 18. Gas flow regulating valve; 19. Gas pipe of upper burners; 20. Upper burners; 21. Lower burners; 22. Smoke exhaust pipe; 23. Hot air flow regulating valve; 24. Opening regulating valve; 25. Cooling fan; 26. Cooling air duct; 27. Bypass pipe. Detailed Embodiments

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. Usually, the components of the embodiments of the present application described and illustrated herein can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0028] It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0029] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0030] The features and performance of the present application will be further described in detail below in conjunction with embodiments.

[0031] Embodiment 1. This embodiment provides a cooling system for the heating hood of a bell-type annealing furnace, as Figures 1 to 3 shown, including: an annealing furnace 1 and a heating hood 2;

[0032] Among them, a heat exchanger 3 and a combustion-supporting fan 4 are installed on the upper part of the outer wall of the heating hood 2. The flue gas inlet of the heat exchanger 3 is connected to the flue gas outlet of the annealing furnace 1 through a smoke exhaust pipe 22. The combustion-supporting fan 4 is connected to the cold air inlet of the heat exchanger 3 through a cold air pipe 7 for the heat exchanger. The hot air outlet of the heat exchanger 3 is connected to a hot air distribution ring pipe 8 installed in the middle of the outer wall of the heating hood 2 through a hot air pipe 13 for the heat exchanger. The hot air distribution ring pipe 8 is connected to the air inlet of the corresponding burner through a plurality of burner hot air pipes;

[0033] A gas distribution ring pipe 16 is installed on the lower part of the outer wall of the heating hood 2. The gas distribution ring pipe 16 is sequentially connected to a gas source through a gas main pipe 14 and a gas joint 11, and the gas distribution ring pipe 16 is connected to the gas inlet of the corresponding burner through a plurality of burner gas pipes;

[0034] The middle part of the cold air pipe 7 for the heat exchanger is communicated with the hot air distribution ring pipe 8 through a bypass pipe 27, and a throttle valve 24 is installed on the bypass pipe 27;

[0035] A cooling fan 25 is installed on one side of the upper part of the outer wall of the heating hood 2 away from the heat exchanger 3. The cooling fan 25 is directly connected to the cold air inlet of the annealing furnace 1 through a cooling air pipe 26.

[0036] Furthermore, the burners are provided with two upper and lower rows on the lower part of the outer wall of the heating hood 2, and each row is provided with six burners, and the upper burners 20 and the lower burners 21 are arranged staggeredly.

[0037] Further, the air inlets of the upper burners 20 are all connected to the hot air distribution manifold 8 through the corresponding upper burner hot air pipes 9; the gas inlets of the upper burners 20 are all connected to the gas distribution manifold 16 through the corresponding upper burner gas pipes 19.

[0038] Further, the air inlets of the lower burners 21 are all connected to the hot air distribution manifold 8 through the corresponding lower burner hot air pipes 10; the gas inlets of the lower burners 21 are all connected to the gas distribution manifold 16 through the corresponding lower burner gas pipes 17.

[0039] Further, an air shut-off valve 6 and an air regulating valve 5 are successively installed on the cold air pipe 7 entering the heat exchanger for the burners, and the bypass pipe 27 is connected to the pipe section of the cold air pipe 7 entering the heat exchanger between the air shut-off valve 6 and the air regulating valve 5.

[0040] Further, a gas shut-off valve 12 and a gas regulating valve 15 are successively installed on the main gas pipe 14. One end of the main gas pipe 14 is connected to a gas source through the gas connector 11, and the other end is connected to the gas distribution manifold 16.

[0041] Further, hot air flow regulating valves 23 are installed on both the upper burner hot air pipes 9 and the lower burner hot air pipes 10.

[0042] Further, gas flow regulating valves 18 are installed on both the upper burner gas pipes 19 and the lower burner gas pipes 17.

[0043] Embodiment 2: Taking the cold rolling bell-type annealing furnace unit of a certain steel plant as an example, this embodiment includes a total of 42 furnace platforms, which are constructed in two phases. In the first phase, 36 furnace platforms do not adopt the cooling system structure of the present application, and the maximum cooling rate cannot exceed 20 °C / h;

[0044] In the second phase, 6 furnace platforms adopt the cooling system structure of the present application. Through actual measurement, the maximum cooling rate can reach nearly 40 °C / h. Compared with the first-phase unit, the annealing time is effectively shortened, and the output of the unit is greatly improved.

[0045] Further, the parts not described in detail in the present application are the same as the prior art or are implemented using the prior art.

[0046] In summary:

[0047] 1. The present utility model provides a cooling system structure for a bell-type annealing furnace heating hood. By adding a bypass pipe that does not pass through the heat exchanger in the middle of the cold air pipe entering the heat exchanger and incorporating it into the hot air distribution manifold, part of the cold combustion-supporting air can be directly blown into the furnace through the burners, thereby improving the cooling rate of the bell-type annealing furnace;

[0048] 2. By arranging a cooling fan and a cooling air duct on the outer wall of the heating hood, the utility model can directly blow cold air into the annealing furnace, so as to further increase the maximum cooling rate of the annealing furnace, effectively shorten the annealing time, and improve the output of the unit.

[0049] 3. The overall structure of the utility model is compact. By modifying the existing bell-type annealing furnace, it does not need to occupy additional installation space, and is convenient to use and easy to maintain in the later stage.

[0050] The above embodiments are only used to illustrate the design concept and characteristics of the utility model, and the purpose is to enable those skilled in the art to understand the content of the utility model and implement it accordingly. The protection scope of the utility model is not limited to the above embodiments. Therefore, all equivalent changes or modifications made according to the principles and design ideas disclosed by the utility model are within the protection scope of the utility model.

Claims

1. A hood-type annealing furnace heating hood cooling system structure, comprising an annealing furnace (1) and a heating hood (2), characterized in that: A heat exchanger (3) and a combustion-supporting fan (4) are installed on the upper part of the outer wall of the heating hood (2); the smoke inlet of the heat exchanger (3) is connected to the smoke outlet of the annealing furnace (1) through a smoke exhaust pipe (22); the combustion-supporting fan (4) is connected to the cold air inlet of the heat exchanger (3) through a cold air pipe (7) entering the heat exchanger; the hot air outlet of the heat exchanger (3) is connected to a hot air distribution ring pipe (8) installed in the middle part of the outer wall of the heating hood (2) through a hot air pipe (13) exiting the heat exchanger; the hot air distribution ring pipe (8) is connected to the air inlets of corresponding burners through a plurality of burner hot air pipes; A gas distribution ring pipe (16) is installed at the lower part of the outer wall of the heating cover (2), and the gas distribution ring pipe (16) is connected to the gas source through the gas main pipe (14) and the gas joint (11) in sequence, and the gas distribution ring pipe (16) is connected to the gas inlet of the corresponding burner through a plurality of burner gas pipes; The middle part of the cold air pipe (7) entering the heat exchanger is connected to the hot air distribution ring pipe (8) through a bypass pipe (27), and an opening regulating valve (24) is installed on the bypass pipe (27); A cooling fan (25) is installed on the side of the upper part of the outer wall of the heating hood (2) away from the heat exchanger (3), and the cooling fan (25) is directly connected to the cold air inlet of the annealing furnace (1) through a cooling air duct (26).

2. A bell-type annealing furnace heating bell cooling system structure according to claim 1, characterized in that: The burners are arranged in two upper and lower rows at the lower part of the outer wall of the heating cover (2), each row is provided with six burners, and the upper burners (20) and the lower burners (21) are arranged alternately.

3. The bell-type annealing furnace heating bell cooling system structure according to claim 2 is characterized in that: The air inlet of the upper burner (20) is connected to the hot air distribution ring pipe (8) through the corresponding upper burner hot air pipe (9); the gas inlet of the upper burner (20) is connected to the gas distribution ring pipe (16) through the corresponding upper burner gas pipe (19).

4. A bell-type annealing furnace heating bell cooling system structure according to claim 3, characterized in that: The air inlet of the lower burner (21) is connected to the hot air distribution ring pipe (8) through the corresponding lower burner hot air pipe (10); the gas inlet of the lower burner (21) is connected to the gas distribution ring pipe (16) through the corresponding lower burner gas pipe (17).

5. The bell-type annealing furnace heating bell cooling system structure according to claim 1, characterized in that: The burner is provided with an air shut-off valve (6) and an air regulating valve (5) in sequence on the cold air pipe (7) entering the heat exchanger, and the bypass pipe (27) is connected to the pipe section of the cold air pipe (7) entering the heat exchanger located between the air shut-off valve (6) and the air regulating valve (5).

6. The bell-type annealing furnace heating bell cooling system structure according to claim 1, characterized in that: A gas shut-off valve (12) and a gas regulating valve (15) are sequentially installed on the gas main pipe (14); one end of the gas main pipe (14) is connected to a gas source via the gas connector (11), and the other end is connected to the gas distribution ring pipe (16).

7. The bell-type annealing furnace heating bell cooling system structure according to claim 4, characterized in that: The upper burner hot air pipe (9) and the lower burner hot air pipe (10) are both installed with hot air flow regulating valves (23).

8. The bell-type annealing furnace heating bell cooling system structure according to claim 4, characterized in that: The upper burner gas pipe (19) and the lower burner gas pipe (17) are both installed with gas flow regulating valves (18).

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