Annealing pretreatment system for double-zero aluminum foil finished product

Abstract

The utility model discloses a double-zero aluminum foil finished product annealing pretreatment system which comprises an annealing furnace group and a hot gas pipeline, the annealing furnace group comprises four annealing furnaces, and each annealing furnace is provided with a negative pressure fan, a circulating fan, a heater and a centrifugal fan; an air inlet of the circulating fan is communicated with the annealing furnace through a hot air pipeline, an air outlet of the circulating fan is communicated with an air inlet of the heater, and an air outlet of the heater is communicated with the annealing furnace through a hot air pipeline; an air inlet of the negative pressure fan is communicated with the annealing furnace through a hot air pipeline, an air outlet of the negative pressure fan is communicated with an air outlet of the centrifugal fan through an exhaust branch pipeline, and an air inlet of the centrifugal fan is communicated with an exhaust main pipeline; the annealing furnaces are communicated through a main exhaust pipeline; each annealing furnace is further provided with a purging valve, and the purging valves are arranged on the hot air pipelines which are communicated with the annealing furnaces through the air inlets of the circulating fans. When the annealing device is used for annealing a double-zero aluminum foil finished product, the technical problems of high-cost foil annealing treatment and annealing hot edge forming can be solved.

Description

1. Technical field:

[0001] The utility model belongs to the technical field of aluminum material processing, and in particular relates to a double-zero aluminum foil finished product annealing pretreatment system. 2. Background technology:

[0002] As a packaging material, double-zero aluminum foil needs to have good formability and a clean and bright surface, and the annealing process is an important part of achieving these goals. The appropriate annealing treatment method is the key to the annealing process. The appropriate annealing treatment method can not only ensure the stability of the quality of the aluminum foil finished product, but also shorten the annealing cycle to improve the annealing efficiency, save the aluminum foil production cost and reduce the aluminum foil loss after annealing.

[0003] At present, aluminum foil manufacturers with a certain production scale can basically maintain the quality of finished aluminum foil products. However, with the decline in the profitability of aluminum foil, the cost awareness of aluminum foil manufacturers has increased, and "cost reduction and efficiency improvement" has become more and more important. The annealing process is the last process of finished aluminum foil processing. The increase in waste caused by annealing heat fringe means a waste of production costs in the previous process. Improper annealing treatment will not only cause the annealing process to operate poorly and inefficiently, but also increase power consumption and increase waste caused by annealing heat fringe. The consequences all mean an increase in costs for aluminum foil manufacturers, a decrease in profits and a weakening of market competitiveness.

[0004] The annealing process requires increasing the temperature to change the mechanical properties of the aluminum foil. Generally, the annealing process is carried out at a certain rate to reach the set target temperature for insulation. However, the situation of annealing heat fringe is not optimistic, because there are many methods in the relevant public literature. In order to improve the heat fringe, some treatments are often done before the coil is annealed. Some technologies use static methods and extend the heating and cooling time. Some technologies use insulation layers in the slitting stage. Some technologies use insulation rooms. Most of the above methods belong to annealing pretreatment methods. These annealing pretreatment methods either greatly reduce the production and operation efficiency or greatly increase the investment cost of the enterprise, which increases the operation cost of the enterprise.

[0005] At present, there are also many patent literature reports on the annealing process of double-zero aluminum foil finished products. For example: 1. The invention patent of CN106521372A discloses a finished annealing process of double-zero aluminum foil. This process allows the slit coil to stand outside the furnace for 12-48 hours, stand in front of the furnace for 24-48 hours, and then slowly heat up and slowly heat up the furnace to reduce the temperature difference of the coil during the annealing process, reduce the internal stress concentration of the coil, and thus achieve the purpose of controlling or reducing the stripping. The existing problems are: the annealing cycle is extremely long, which increases the annealing production pressure, increases the investment cost, and increases the energy waste. 2. The invention patent of CN 207121631 U discloses a preheating system for a double-zero aluminum foil annealing furnace. The system achieves slow heating of the annealing material and slow cooling of the out-of-furnace material by constructing a preheating room for the annealing material and a cooling room for the out-of-furnace material, and performs heat exchange and heating in the preheating room, thereby reducing the stress concentration inside the coil and effectively preventing the stripping of the finished product. The existing problems are: the construction costs of the preheating room, cooling room and supporting facilities are high, which increases the transportation and static process of the coils to be annealed, increases the annealing production pressure, and increases the production cost. 3. Utility Model Content:

[0006] The technical problem to be solved by the utility model is: in view of the processing conditions of the existing double zero aluminum foil annealing process or device and the existing annealing heat edge problem, the utility model provides a double zero aluminum foil finished product annealing pretreatment system. By using the utility model system to anneal the double zero aluminum foil finished product, the technical problems of high cost annealing of foil and annealing heat edge can be solved.

[0007] In order to solve the above problems, the technical solution adopted by the utility model is:

[0008] The utility model provides a double-zero aluminum foil finished product annealing pretreatment system, comprising an annealing furnace group and a hot air pipeline, wherein: the annealing furnace group comprises four annealing furnaces, each annealing furnace is equipped with a negative pressure fan, a circulating fan, a heater and a centrifugal fan; the circulating fan air inlet is connected with the annealing furnace through the hot air pipeline, the air outlet is connected with the heater air inlet, the heater air outlet is connected with the annealing furnace through the hot air pipeline; the negative pressure fan air inlet is connected with the annealing furnace through the hot air pipeline, the air outlet is connected with the centrifugal fan air outlet through the exhaust branch pipeline, the centrifugal fan air inlet is connected with the exhaust main pipeline; the annealing furnaces are connected through the exhaust main pipeline.

[0009] According to the above-mentioned double-zero aluminum foil finished product annealing pretreatment system, the air inlet of the negative pressure fan provided in each annealing furnace is located at the top of the annealing furnace furnace, the air outlet of the negative pressure fan is connected to the exhaust branch pipe through a flange, the end of the exhaust branch pipe is connected to the air outlet of the centrifugal fan through a flange, and the air inlet of the centrifugal fan is connected to the exhaust main pipe through a flange.

[0010] According to the above-mentioned double-zero aluminum foil finished product annealing pretreatment system, the centrifugal fan includes an impeller, a casing, an air inlet, an air outlet, an adjusting damper and a driving device.

[0011] According to the above-mentioned double-zero aluminum foil finished product annealing pretreatment system, the power of the centrifugal fan is 330W, and the maximum air volume is 11m3 / min, which is less than the power of the negative pressure fan of 7.5KW and the air volume of 43m3 / min.

[0012] According to the above-mentioned double-zero aluminum foil finished product annealing pretreatment system, the frequency of the negative pressure fan is set to 25-35 Hz (the frequency of my country's power grid is 50 Hz; this is used to regulate the operating power and air volume of the negative pressure fan).

[0013] According to the above-mentioned double-zero aluminum foil finished product annealing pretreatment system, each annealing furnace is also equipped with a purge valve, and the purge valve is arranged on the hot air pipeline connected to the annealing furnace through the hot air pipeline at the air inlet of the circulating fan.

[0014] In the double-zero aluminum foil finished product annealing pretreatment system of the utility model, the air inlet of each centrifugal fan is connected to the exhaust main pipeline, and the air outlet of each centrifugal fan and the air outlet of each negative pressure fan are in the opposite direction of the axis of each annealing furnace exhaust branch pipeline.

[0015] The technical scheme principle of the double-zero aluminum foil finished product annealing pretreatment system of the utility model is: utilizing the combined effects of the annealing furnace circulation fan and the negative pressure fan, designing the annealing furnace exhaust duct according to the hot air passing path, each centrifugal fan is connected to each annealing furnace exhaust branch duct and the exhaust main duct, so that each annealing furnace group is an annealing pretreatment system; in this annealing pretreatment system, sufficient hot air can be called for heating the foil in the annealing furnace. The application of the utility model does not require additional high-cost investment, and the finished aluminum foil does not need to be left still or circulated. It can be directly put into the furnace for annealing pretreatment after slitting. The average power consumption per hour in the annealing pretreatment stage is about 2Kwh, which is 78Kwh per hour compared with the average power consumption of 78Kwh per hour at a heating rate of 5℃ / h, that is, 76Kwh of power consumption per hour is saved; and after annealing pretreatment, the aluminum foil roll with a length of less than 20,000 meters has almost completely disappeared, and the proportion of annealing heat-ripening waste for aluminum foil rolls with a length of more than 20,000 meters has dropped significantly, from a maximum of 6.86% to a minimum of 1.52%. Therefore, the utility model fully realizes the cost reduction and efficiency improvement in the aluminum foil production process, and has outstanding technical advantages.

[0016] The hot air paths of the annealing pretreatment system of the double-zero aluminum foil finished product of the utility model are divided into two types. The first type is: when the four annealing furnaces in the annealing furnace group are all performing normal annealing processes, the centrifugal fan does not work, and the hot air is drawn into the exhaust branch pipe by the negative pressure fan, enters the exhaust main pipe through the centrifugal fan, and then is discharged into the atmosphere; the second type is: when there is an annealing furnace (such as: 1# annealing furnace) in the annealing furnace group for annealing pretreatment, the centrifugal fan is started, and the hot air is drawn into the exhaust branch pipe by the negative pressure fan provided in other annealing furnaces in the annealing furnace group (such as: 2#, 3#, 4# annealing furnaces), and then enters the exhaust main pipe. Part of the hot air in the exhaust main pipe is drawn into the exhaust branch pipe of the annealing furnace (1# annealing furnace) for annealing pretreatment through the centrifugal fan, and then enters the annealing furnace for annealing pretreatment, and is used to heat the foil in the furnace, and the remaining hot air is discharged into the atmosphere.

[0017] The operation process of the utility model double zero aluminum foil finished product annealing pretreatment system:

[0018] a. First, confirm whether there are both vacant annealing furnaces and normally operating annealing furnaces in the finished product annealing pretreatment system; if both exist, push the aluminum foil rolls to be annealed that do not need to be left still into the vacant annealing furnace, close and press the furnace door (the temperature of the aluminum foil rolls to be annealed is room temperature), and keep the annealing furnace hearth in a closed state; if all are vacant annealing furnaces, start one of the empty furnaces for heating (the empty furnace has a fast heating speed and low power consumption), then push the aluminum foil rolls to be annealed that do not need to be left still into the vacant annealing furnace, close and press the furnace door, and keep the annealing furnace hearth in a closed state;

[0019] b. Then set the frequency of the circulating fan of the annealing furnace equipped with the aluminum foil coil to be annealed (the frequency of the circulating fan is set to 20-40Hz; the frequency of my country's power grid is 50Hz), and start it after setting, so that the furnace of the annealing furnace and the aluminum foil coil to be annealed can exchange heat. When the overall temperature in the furnace drops to room temperature, it tends to be stable (the temperature in winter and summer is 25-45℃; this process takes less than 3 hours to complete);

[0020] c. After stabilizing, start the centrifugal fan of the hot gas duct of the annealing furnace, and adjust the damper of the centrifugal fan to control the hot gas replenishment volume to 5-9m3 / min (according to the production situation). At this time, the hot gas extracted from other annealing furnaces in the system is injected into the annealing furnace through the exhaust duct to improve the atmosphere in the furnace and heat the aluminum foil coil. At the same time, set the opening of the purge valve to 10-50% (to avoid the furnace temperature rising too fast);

[0021] d. (The width of the annealed aluminum foil roll is generally 300-1600mm) According to the width of the aluminum foil roll, the operation time of the centrifugal fan is set to 3-8h. During this period, the centrifugal fan transports hot air to the aluminum foil roll to be processed, and the corresponding furnace temperature will rise to 30-55℃. At this time, the centrifugal fan is turned off and the annealing pretreatment is completed (the above parameters can be controlled and adjusted by the upper computer system, which is simple to operate and easy to monitor);

[0022] e. After the annealing pretreatment of the finished double-zero aluminum foil is completed, the annealing process operation program is started (during the entire annealing process, the centrifugal fan stops working, and the openings of the circulating fan, negative pressure fan and purge valve in each heating and cooling and insulation stage are set to fixed values, respectively set to 40Hz, 30Hz and 50%, to maintain the stability of the annealing furnace inlet and outlet air volume and uniform furnace temperature changes).

[0023] The positive and beneficial effects of the utility model:

[0024] 1. The principle of the technical solution of the utility model is based on the combination of the circulating fan and the negative pressure fan of the annealing furnace; the hot air intercommunication between the four annealing furnaces is realized through the hot air pipeline, forming an annealing pretreatment system.

[0025] 2. The technical solution of the utility model breaks the inherent idea that the annealing furnace only uses a negative pressure fan to extract the hot air in the furnace. The centrifugal fan arranged in the hot air pipeline can call part of the hot air to fill the furnace, heating the foil while also utilizing part of the waste heat.

[0026] 3. The construction of the double-zero aluminum foil annealing pretreatment system of the utility model does not require additional high cost investment. In the annealing pretreatment system of the utility model, the pretreatment period is short and the energy consumption is low. The hot air discharged during the operation of the annealing furnace is effectively used to heat the aluminum foil, reducing energy waste; the entire pretreatment stage takes 6 to 11 hours, and the aluminum foil does not need to be left still or circulated, thereby improving production efficiency. Calculated based on the power consumption saving of 76Kwh per hour, the entire pretreatment stage can save 456 to 836Kwh of power consumption. If 2,400 tons of aluminum foil are produced monthly, the average annealing furnace is about 80 times, that is, 36,480 to 66,880Kwh of power consumption can be saved per month.

[0027] 4. The aluminum foil coils treated by the double-zero aluminum foil annealing pretreatment system of the utility model have a significant improvement effect on the annealing heat fringe condition. The generation rate of annealing heat fringe has been reduced from the original 18% to below 5%, and the degree of annealing heat fringe has been significantly reduced. The amount of scrap generated by the hot drum of the aluminum foil coils has been reduced by more than 90%, and the comprehensive yield rate has been increased by nearly 2%, with obvious direct economic benefits. 4. Description of the drawings:

[0028] Figure 1Front view and side view of the structural principle of the operation state of a single annealing furnace in the pretreatment stage of the system of the utility model;

[0029] Figure 2 A schematic diagram of the structure of a double-zero aluminum foil finished product annealing pretreatment system of the utility model.

[0030] In the figure: 1. negative pressure fan, 2. circulating fan, 3. heater, 4. exhaust main duct, 5. foil coil to be processed, 6. centrifugal fan, 7. circulating air, 8. negative pressure fan extracts hot air from the furnace, 9. centrifugal fan transports hot air into the furnace, 10. exhaust branch duct, 11. 1# annealing furnace in the pretreatment system, 12. 2# annealing furnace in the pretreatment system, 13. 3# annealing furnace in the pretreatment system, 14. 4# annealing furnace in the pretreatment system; 21. purge valve, 22. hot air discharged into the atmosphere. V. Specific implementation methods:

[0031] The present invention is further described below in conjunction with embodiments, but the scope of protection of the technical solution of the present invention is not limited thereto.

[0032] Embodiment 1:

[0033] The utility model discloses a double-zero aluminum foil finished product annealing pretreatment system, comprising an annealing furnace group and a hot air pipeline, wherein the annealing furnace group comprises four annealing furnaces (i.e., 1# annealing furnace 11, 2# annealing furnace 12, 3# annealing furnace 13, and 4# annealing furnace 14), each of which is equipped with a negative pressure fan 1, a circulating fan 2, a heater 3, and a centrifugal fan 6; the air inlet of the circulating fan 2 is connected to the annealing furnace through the hot air pipeline, the air outlet is connected to the air inlet of the heater 3, and the air outlet of the heater 3 is connected to the annealing furnace through the hot air pipeline; the air inlet of the negative pressure fan 1 is connected to the annealing furnace through the hot air pipeline, the air outlet is connected to the air outlet of the centrifugal fan 6 through the exhaust branch pipeline 10, and the air inlet of the centrifugal fan 6 is connected to the exhaust main pipeline 4; the annealing furnaces are connected through the exhaust main pipeline 4.

[0034] Furthermore, the air inlet of the negative pressure fan 1 provided in each annealing furnace is located at the top of the annealing furnace furnace, the air outlet of the negative pressure fan 1 is connected to the exhaust branch pipe 10 through a flange, the end of the exhaust branch pipe 10 is connected to the air outlet of the centrifugal fan 6 through a flange, and the air inlet of the centrifugal fan 6 is connected to the exhaust main pipe 4 through a flange.

[0035] Furthermore, the centrifugal fan includes an impeller, a casing, an air inlet, an air outlet, an adjusting damper and a driving device; the power of the centrifugal fan is 330W, and the maximum air volume is 11m3 / min, which is less than the power of the negative pressure fan of 7.5KW and the air volume of 43m3 / min; the frequency of the negative pressure fan is set to 25-35Hz (the frequency of my country's power grid is 50Hz; this is used to regulate the operating power and air volume of the negative pressure fan).

[0036] Furthermore, each annealing furnace is also equipped with a purge valve 21, and the purge valve 21 is arranged on the hot air pipeline connected to the annealing furnace through the hot air pipeline at the air inlet of the circulating fan 2.

[0037] The relevant results of annealing the double-zero aluminum foil finished product using the annealing pretreatment system of the utility model are shown in Tables 1 to 4.

[0038] Table 1 The first set of test data for processing double zero aluminum foil finished products using the utility model system in summer

[0039]

[0040] Table 2 The second set of test data of double zero aluminum foil finished products processed by the utility model system in summer

[0041]

[0042] Table 3 The first set of test data of using the utility model system to process double zero aluminum foil finished products in winter

[0043]

[0044] Table 4 The second set of test data of double zero aluminum foil finished products processed by the utility model system in winter

[0045]

[0046] It can be seen from the above test data that the use of the system of the utility model to anneal the finished double-zero aluminum foil can solve the technical problems of high-cost foil annealing and annealing heat fringe.

Claims

1. A double zero aluminum foil finished product annealing pretreatment system, comprising an annealing furnace group and a hot air pipeline, characterized in that: The annealing furnace group includes four annealing furnaces, each of which is equipped with a negative pressure fan, a circulating fan, a heater and a centrifugal fan; the air inlet of the circulating fan is connected to the annealing furnace through a hot air duct, and the air outlet is connected to the air inlet of the heater, and the air outlet of the heater is connected to the annealing furnace through a hot air duct; the air inlet of the negative pressure fan is connected to the annealing furnace through a hot air duct, and the air outlet is connected to the air outlet of the centrifugal fan through an exhaust branch duct, and the air inlet of the centrifugal fan is connected to the exhaust main duct; the annealing furnaces are connected through the exhaust main duct.

2. The double zero aluminum foil finished product annealing pretreatment system according to claim 1 is characterized in that: The air inlet of the negative pressure fan provided in each annealing furnace is located at the top of the annealing furnace furnace, the air outlet of the negative pressure fan is connected to the exhaust branch pipe through a flange, the end of the exhaust branch pipe is connected to the air outlet of the centrifugal fan through a flange, and the air inlet of the centrifugal fan is connected to the exhaust main pipe through a flange.

3. The double zero aluminum foil finished product annealing pretreatment system according to claim 1 is characterized in that: The centrifugal fan comprises an impeller, a casing, an air inlet, an air outlet, an adjusting damper and a driving device.

4. The double zero aluminum foil finished product annealing pretreatment system according to claim 3 is characterized in that: The power of the centrifugal fan is 330W, and the maximum air volume is 11m3 / min, which is less than the power of the negative pressure fan of 7.5KW and the air volume of 43m3 / min.

5. The double zero aluminum foil finished product annealing pretreatment system according to claim 3 is characterized in that: The frequency of the negative pressure fan is set to 25-35 Hz.

6. The double zero aluminum foil finished product annealing pretreatment system according to claim 1, characterized in that: Each annealing furnace is also equipped with a purge valve, which is arranged on a hot air pipeline connected to the annealing furnace through the hot air pipeline at the air inlet of the circulating fan.

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