Novel passivating, drying and heating system
By adding a burner and temperature sensor inside the passivation drying oven, utilizing the residual heat of the furnace area for supplemental heating, and combining this with the insulation layer and axial flow fan for rapid cooling, the problem of insufficient passivation drying temperature for galvanized aluminum-magnesium strip steel was solved, achieving efficient passivation and energy-saving effects.
Patent Information
- Application Number
- CN202423159262.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-12-20
AI Technical Summary
In the existing passivation and drying process of galvanized aluminum-magnesium strip steel, the passivation drying box is too short and the heat source temperature is insufficient, making it difficult to reach the passivation drying temperature required by the process, which affects product quality and customer satisfaction.
A new passivation drying heating system is adopted. By adding burners and temperature sensors in the passivation drying box, the residual heat recovered from the furnace process is used for supplemental heating. Combined with the insulation layer and axial flow fan for rapid cooling, the galvanized aluminum-magnesium strip steel reaches and maintains a suitable temperature.
It achieves effective passivation and drying of galvanized aluminum-magnesium strip steel, meets the temperature range required for passivation, improves thermal energy utilization, reduces fuel consumption, and ensures product quality.
Smart Images
Figure CN223512434U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of passivation of galvanized aluminum-magnesium strip steel. Background Technology
[0002] Passivation refers to the process of treating metals with strong oxidizing agents or electrochemical methods to make the surface inactive, thus slowing down the corrosion rate of the metal. Zinc-aluminum-magnesium steel strips can be passivated using roller coating. The passivation solution is evenly coated onto the surface of the strip using a passivation roller, and then cured at high temperature, forming a layer of zinc, a passivation film, and aluminum oxide on the surface, thereby improving the material's corrosion resistance. Roller coating offers strong passivation capabilities, extends the material's service life, and produces a uniform and dense passivation film, effectively improving the corrosion resistance of zinc-aluminum-magnesium materials.
[0003] In the production process of galvanized aluminum-magnesium strip steel, passivation is one of the main methods to improve the corrosion resistance of the coating. When passivation is performed by roll coating, the galvanized aluminum-magnesium strip steel needs to be dried after roll coating. Generally, this is done in a passivation drying oven. The heat source for drying is the waste heat recovered from the furnace process, with a waste heat temperature of approximately 130℃. The passivation drying temperature for galvanized aluminum-magnesium strip steel is required to reach 70-80℃. However, due to the short length of the passivation drying oven (only about 7 meters), and under full-load production conditions of 120TV, the heating time is only about 4-8 seconds. After the strip steel is heated in the drying oven, the passivation drying temperature cannot reach the process requirement of 70℃. In addition, cooling should be carried out in a timely manner after passivation drying to ensure that the plate temperature is below 45℃ before coiling. When the process does not meet the requirements, the salt spray test of the zinc-aluminum-magnesium product will be unsatisfactory. The product will develop white rust within 24 hours when it enters the water at the downstream customer's location, causing product quality defects, reducing customer satisfaction, and affecting product competitiveness. Utility Model Content
[0004] The technical problem to be solved by this utility model is: how to overcome the technical problems in the background and achieve good passivation of galvanized aluminum-magnesium strip steel.
[0005] The technical solution adopted in this utility model is as follows: a novel passivation drying heating system, wherein the conveyor roller 2 carries galvanized aluminum-magnesium strip steel from bottom to top through the passivation drying box 1, the galvanized aluminum-magnesium strip steel is heated and dried in the passivation drying box 1, the lower side of the passivation drying box 1 is connected to the drying box air inlet pipe 7, the inside of the passivation drying box 1 has multiple first nozzles 18 facing the plate surface of the galvanized aluminum-magnesium strip steel inside the passivation drying box 1, each nozzle is connected to the drying box air inlet pipe 7, the upper part of the passivation drying box 1 has a correction roller 10 and a looper 8, the waste heat pipe for recovering waste heat from the furnace process heat energy is connected to the combustion chamber air inlet pipe 12, the combustion chamber air outlet pipe 13 is connected to the drying box air inlet pipe 7, the combustion chamber 14 has a burner for supplemental heating inside, the burner air inlet pipe 15 is equipped with a first air valve 16, and a temperature sensor 17 is also installed inside the combustion chamber 14.
[0006] The passivation drying oven 1 is equipped with an upper left baffle 3 and an upper right baffle 4 on its upper side. The upper left baffle 3 is rotatably connected to the left side plate of the passivation drying oven 1, and the upper right baffle 4 is rotatably connected to the right side plate of the passivation drying oven 1. The passivation drying oven 1 is equipped with a lower left baffle 5 and a lower right baffle 6 on its lower side. The lower left baffle 5 is rotatably connected to the left side plate of the passivation drying oven 1, and the lower right baffle 6 is rotatably connected to the right side plate of the passivation drying oven 1.
[0007] The passivation drying oven 1 has an insulation layer 11 on its outer side.
[0008] An axial flow fan 9 is located between the straightening roller 10 and the looper 8, with the second nozzle of the axial flow fan 9 facing the surface of the galvanized aluminum-magnesium strip steel.
[0009] The two fixed rollers at the inlet of loop 8 are water-cooled rollers.
[0010] In the operation of this utility model, the conveyor roller 2 carries the galvanized aluminum-magnesium strip steel (after hot dipping) through the passivation drying box 1. The upper left baffle 3, upper right baffle 4, lower left baffle 5, and lower right baffle 6 are all in a closed state. The function of the upper left baffle 3, upper right baffle 4, lower left baffle 5, and lower right baffle 6 is to enhance the heat preservation effect. The hot air recovered from the furnace process heat energy enters the combustion chamber air inlet pipe 12 through the waste heat pipe, and then enters the combustion chamber 14. The temperature of the hot air (hot air) entering through the waste heat pipe is about 130℃. In order to meet the passivation drying requirements of the galvanized aluminum-magnesium strip steel inside the passivation drying box 1, the temperature of the hot air entering the passivation drying box 1 needs to be 320℃-350℃. In this invention, the temperature of the hot gas is increased by combustion through a burner located inside the combustion chamber 14 for supplemental heating. The temperature of the hot gas is adjusted by adjusting the opening of the first gas valve 16. When the temperature sensor 17 inside the combustion chamber 14 detects that the temperature of the hot gas inside the combustion chamber 14 meets the requirements, the second gas valve on the combustion chamber outlet pipe 13 (there is a second gas valve on the combustion chamber outlet pipe 13) is opened. The hot gas inside the combustion chamber 14 flows through the combustion chamber outlet pipe 13 and the intermediate connecting pipe (connecting the combustion chamber outlet pipe 13 and the drying...) The air inlet pipe 7 of the drying chamber enters the passivation drying chamber 1, which then passesivates and dries the galvanized aluminum-magnesium strip steel in the passivation drying chamber 1. The hot air entering from the drying chamber air inlet pipe 7 is cooled and discharged through the upper and lower openings of the passivation drying chamber 1. The temperature of the dried galvanized aluminum-magnesium strip steel is 70-80℃. Under the action of the two fixed rollers (water-cooled) at the inlet of the looper 8 and the axial flow fan 9 (blowing cold air to the galvanized aluminum-magnesium strip steel), the temperature of the galvanized aluminum-magnesium strip steel is rapidly reduced to below 45℃, thereby enabling the galvanized aluminum-magnesium strip steel to meet the passivation requirements.
[0011] The beneficial effects of this utility model are as follows: This utility model can meet the passivation drying requirements of galvanized aluminum-magnesium strip steel. This utility model enhances the heat preservation effect of the passivation drying chamber 1 by adding the upper left baffle 3, upper right baffle 4, lower left baffle 5, and lower right baffle 6. It also enhances the heat preservation effect of the passivation drying chamber 1 by installing an insulation layer 11 on the outside of the passivation drying chamber 1. By enhancing the heat preservation effect, the utilization rate of hot air is improved, thereby reducing the fuel consumption of the burner used for supplemental heating. The combustion chamber in this utility model increases the temperature of the hot air, thereby increasing the temperature in the passivation drying chamber, ensuring that the temperature of the galvanized aluminum-magnesium strip steel leaving the passivation drying chamber 1 is 70-80℃, meeting the passivation drying requirements. Under the action of the two fixed rollers (water-cooled) at the inlet of the looper 8 and the axial flow fan 9 (blowing cold air onto the galvanized aluminum-magnesium strip steel), the temperature of the galvanized aluminum-magnesium strip steel is rapidly reduced to below 45℃, thus meeting the passivation requirements. Attached Figure Description
[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0013] Figure 2This is a schematic diagram of the combustion chamber of this utility model;
[0014] Among them, 1. passivation drying box, 2. conveyor roller, 3. upper left baffle, 4. upper right baffle, 5. lower left baffle, 6. lower right baffle, 7. drying box air inlet pipe, 8. looper, 9. axial flow fan, 10. correction roller, 11. heat insulation layer, 12. combustion chamber air inlet pipe, 13. combustion chamber air outlet pipe, 14. combustion chamber, 15. burner air inlet pipe, 16. first air valve, 17. temperature sensor, 18. first nozzle. Detailed Implementation
[0015] like Figure 1 and Figure 2 As shown, a novel passivation drying and heating system is presented, which is an improvement on the existing passivation drying and heating system.
[0016] In existing passivation drying heating systems, conveyor rollers 2 carry galvanized aluminum-magnesium steel strips from bottom to top through the passivation drying chamber 1. The galvanized aluminum-magnesium steel strips are heated and dried in the passivation drying chamber 1. The lower side of the passivation drying chamber 1 is connected to the air inlet pipe 7. Inside the passivation drying chamber 1, there are multiple first nozzles 18 facing the surface of the galvanized aluminum-magnesium steel strips inside the passivation drying chamber 1. Each nozzle is connected to the air inlet pipe 7. The upper part of the passivation drying chamber 1 has a straightening roller 10 and a looper 8. In one embodiment, the passivation drying chamber is about 7 meters long. The hot air used in the passivation drying chamber 1 is generated from the waste heat recovered from the furnace process, and the temperature is about 130°C. When the holding time in the passivation drying chamber 1 is 4-8 seconds, the temperature of the galvanized aluminum-magnesium steel strips is below 70°C when they leave, which does not meet the passivation drying requirements. Therefore, either the holding time or the passivation drying temperature needs to be increased. Otherwise, the passivation requirements cannot be met. However, the production line is operating at full capacity, leaving only 4-8 seconds for drying (the time from when the galvanized aluminum-magnesium strip enters the passivation drying chamber to when it leaves). Therefore, the only option is to increase the drying temperature.
[0017] In this utility model, the waste heat pipe for the furnace area process heat energy recovery is connected to the combustion chamber inlet pipe 12, the combustion chamber outlet pipe 13 is connected to the drying box inlet pipe 7, the combustion chamber 14 has a burner for heat replenishment inside, the burner inlet pipe 15 is equipped with a first gas valve 16, and the combustion chamber 14 is also equipped with a temperature sensor 17.
[0018] The passivation drying oven 1 is equipped with an upper left baffle 3 and an upper right baffle 4 on its upper side. The upper left baffle 3 is rotatably connected to the left side plate of the passivation drying oven 1, and the upper right baffle 4 is rotatably connected to the right side plate of the passivation drying oven 1. The passivation drying oven 1 is equipped with a lower left baffle 5 and a lower right baffle 6 on its lower side. The lower left baffle 5 is rotatably connected to the left side plate of the passivation drying oven 1, and the lower right baffle 6 is rotatably connected to the right side plate of the passivation drying oven 1.
[0019] Compared to the absence of the upper left baffle 3, upper right baffle 4, lower left baffle 5, and lower right baffle 6, the heat preservation efficiency can be effectively enhanced. In addition, the passivation drying oven 1 has an insulation layer 11 on the outside, which can further enhance the heat preservation effect, thereby enabling the galvanized aluminum-magnesium strip steel to meet the drying requirements in a short time.
[0020] Furthermore, according to passivation requirements, the dried galvanized aluminum-magnesium steel strip needs to be rapidly cooled to below 45°C. This invention addresses this by installing an axial flow fan 9 between the straightening roller 10 and the looper 8, and replacing the two fixed rollers at the inlet of the looper 8 with water-cooled rollers. This ensures the dried galvanized aluminum-magnesium steel strip can be rapidly cooled to below 45°C.
[0021] In one embodiment, the upper left baffle 3, upper right baffle 4, lower left baffle 5, and lower right baffle 6 are opened when the conveyor rollers inside the passivation drying oven 1 are waiting for maintenance, and are closed when in operation.
[0022] The conveyor roller 2 carries the galvanized aluminum-magnesium strip steel (after hot dipping) through the passivation drying box 1. The hot air recovered from the furnace process heat energy (the hot air obtained by exchanging heat between air and the waste heat of the blast furnace) enters the combustion chamber air inlet pipe 12 through the waste heat pipe, and then enters the combustion chamber 14. The temperature of the hot air (hot air) entering through the waste heat pipe is about 130℃. In order to meet the passivation drying requirements of the galvanized aluminum-magnesium strip steel inside the passivation drying box 1, the temperature of the hot air entering the passivation drying box 1 needs to be 320℃-350℃. The temperature of the hot air is increased by combustion in the burner inside the combustion chamber 14 for supplemental heating. The temperature of the hot air is adjusted by adjusting the opening of the first gas valve 16. When the temperature sensor 17 in the combustion chamber 14 detects that the temperature of the hot air in the combustion chamber 14 meets the requirements, the second gas valve on the pipe of the combustion chamber outlet pipe 13 (there is a second gas valve on the pipe of the combustion chamber outlet pipe 13) is opened. The hot air in the combustion chamber 14 enters the passivation drying box 1 through the combustion chamber outlet pipe 13, the intermediate connecting pipe (the pipe connecting the combustion chamber outlet pipe 13 and the drying box inlet pipe 7), and the drying box inlet pipe 7, thereby passivating and drying the galvanized aluminum-magnesium strip steel in the passivation drying box 1. The hot air entering from the drying box inlet pipe 7 is cooled and discharged through the drying box outlet pipe. An insulation layer is installed on the exterior of the passivation drying box 1. In one embodiment, the insulation layer is a 100mm thick rock wool composite board, which adds external insulation to the existing passivation drying box and reduces heat dissipation of the passivation drying box. The dried galvanized aluminum-magnesium steel strip is conveyed out. The temperature of the dried galvanized aluminum-magnesium steel strip is 70-80℃. Under the action of the two fixed rollers (water-cooled) at the inlet of the looper 8 and the axial flow fan 9 (blowing cold air to the galvanized aluminum-magnesium steel strip), the temperature of the galvanized aluminum-magnesium steel strip is rapidly reduced to below 45℃, so that the galvanized aluminum-magnesium steel strip meets the passivation requirements.
Claims
1. A novel passivation drying heating system, wherein a conveyor roller (2) carries galvanized aluminum-magnesium strip steel from bottom to top through a passivation drying box (1), the galvanized aluminum-magnesium strip steel is heated and dried in the passivation drying box (1), the lower side of the passivation drying box (1) is connected to a drying box air inlet pipe (7), the inside of the passivation drying box (1) has multiple first nozzles (18) facing the plate surface of the galvanized aluminum-magnesium strip steel inside the passivation drying box (1), each nozzle is connected to the drying box air inlet pipe (7), the upper part of the passivation drying box (1) has a correction roller (10) and a looper (8), characterized in that: The waste heat pipeline for recovering waste heat from the furnace process is connected to the combustion chamber inlet pipe (12), the combustion chamber outlet pipe (13) is connected to the drying box inlet pipe (7), the combustion chamber (14) contains a burner for supplemental heating, the burner inlet pipe (15) is equipped with a first gas valve (16), and the combustion chamber (14) is also equipped with a temperature sensor (17).
2. The novel passivation drying heating system according to claim 1, characterized in that: The upper side of the passivation drying oven (1) is equipped with an upper left baffle (3) and an upper right baffle (4). The upper left baffle (3) is rotatably connected to the left side plate of the passivation drying oven (1), and the upper right baffle (4) is rotatably connected to the right side plate of the passivation drying oven (1). The lower side of the passivation drying oven (1) is equipped with a lower left baffle (5) and a lower right baffle (6). The lower left baffle (5) is rotatably connected to the left side plate of the passivation drying oven (1), and the lower right baffle (6) is rotatably connected to the right side plate of the passivation drying oven (1).
3. The novel passivation drying heating system according to claim 1, characterized in that: The passivation drying oven (1) has an insulation layer (11) on the outside.
4. The novel passivation drying heating system according to claim 1, characterized in that: An axial flow fan (9) is located between the straightening roller (10) and the looper (8), with the second nozzle of the axial flow fan (9) facing the surface of the galvanized aluminum-magnesium strip.
5. The novel passivation drying heating system according to claim 1, characterized in that: The two fixed rollers at the inlet of the looper (8) are water-cooled rollers.