Production method of aluminum alloy cold-rolled coiled material

Abstract

The invention discloses a production method of an aluminum alloy cold-rolled coiled material, and relates to the technical field of aluminum alloy coiled material preparation. The specific production method comprises the following steps that S1, rolling is conducted, specifically, a cast ingot is obliquely rolled to increase the width, then longitudinal rolling is conducted, and an aluminum coil is obtained; s2, cleaning and sewing are conducted, specifically, 2-3 aluminum rolls are placed on a sewing device of a cleaning machine to be sewn and combined, and the pressure of the sewing device is 12-13 Mpa; s3, heat treatment: carrying out heat treatment on the cleaned and sewn coiled material; and S4, withdrawal and straightening: straightening and shearing the coiled material subjected to heat treatment through a withdrawal and straightening machine to obtain a finished product. The method solves the problems of low subsequent heat treatment production efficiency and low yield of the aluminum alloy cold-rolled coiled material with the width larger than or equal to 2500mm, the ingot casting width can be reduced to a greater extent, scrap caused by cracks generated in ingot casting is avoided, meanwhile, the weight of a single coil can be increased, the equipment operation amount is reduced, waste generation is reduced, the production efficiency is improved, and the production cost is reduced. And large-scale production is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy coil preparation, and in particular to a production method of aluminum alloy cold-rolled coil. Background Art

[0002] As the demand for aluminum alloy coils continues to increase, industry competition is becoming increasingly fierce. Aluminum processing companies hope to reduce production costs and improve market competitiveness by increasing production capacity per unit time and improving production efficiency. At present, the equipment of aluminum processing companies is getting larger and larger, the width of products is getting wider and wider, and the required ingot width is also getting wider and wider. However, the wider the ingot width, the easier it is to produce crack defects during the casting process.

[0003] In the prior art, aluminum alloy coils with a width of ≥2500mm are made from ingots of the following specifications: ingot width = finished product width - (100-800mm), ingot maximum length = rolling mill roll width - (150-200)mm, ingot thickness = 500-650mm. The width is increased to: finished product width + (100-200)mm by transverse rolling of the ingot, and then longitudinal rolling is performed. The disadvantage of this technology is that the ingot length is limited by the width of the rolling mill, and the weight of a single coil is only 8-12 tons (the weight of a single coil designed and produced by the equipment is 20-30 tons). At the same time, the subsequent heat treatment production efficiency is low and the yield rate is low. Patent CN 114774657 A discloses a method for preparing a high-strength and thin 7-series aluminum alloy strip. The method is to mechanically stitch, thread, pre-clean, solid solution, quench, and pre-stretch the 7-series aluminum alloy strip cold-rolled to a thickness of 0.10-0.50 mm in an air cushion continuous annealing furnace, and then perform box-type artificial aging annealing to obtain a high-strength and thin 7-series aluminum alloy strip. However, the air cushion continuous annealing furnace has high equipment investment costs and process production costs, and can only be applied to 0.1-0.5 mm strips. At the same time, the stitching operation is only for threading the strip through the air cushion continuous annealing furnace, and the size of the coil after passing through is still the original size.

[0004] Based on the above problems, the purpose of this application is to provide a method for producing aluminum alloy cold-rolled coils. Summary of the invention

[0005] In view of the above shortcomings, the present invention provides a method for producing aluminum alloy cold-rolled coils, which solves the problems of low production efficiency and low yield of subsequent heat treatment of aluminum alloy cold-rolled coils with a width of ≥2500mm. The specific technical scheme is as follows:

[0006] A method for producing an aluminum alloy cold-rolled coil comprises the following steps:

[0007] S1. Rolling: firstly, the ingot is rolled obliquely to increase the width, and then longitudinally rolled to obtain the aluminum coil;

[0008] The width of the ingot = the finished product width - (200-1000) mm, the length of the ingot = the rolling mill roll surface width + (100-800) mm, and the thickness of the ingot = 500-650 mm;

[0009] S2. Cleaning and sewing: 2 to 3 aluminum coils are placed on the sewing device of the cleaning machine for sewing and rolling. The pressure of the sewing device is 12 to 13 MPa. If the sewing pressure is too small, the sewing will not be firm. If the sewing pressure is too large, it will easily cause serious deformation of the sewing part, and the coil near the sewing head will be squeezed and deformed during annealing.

[0010] S3, heat treatment: heat treatment of the cleaned and stitched coils;

[0011] S4, Straightening: The heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product.

[0012] Furthermore, in step S1, when the ingot is obliquely rolled, the ingot head is placed at an angle of 15 to 60 degrees to the rolling roller.

[0013] Furthermore, in step S1, the thickness of the aluminum coil is 1 to 1.2 mm.

[0014] Furthermore, in step S2, the initial tensile stress of the cleaning machine is 14-18 MPa, and the tensile stress of the cleaning machine after suturing is set to 70-80% of the initial tensile stress. If the tension is too large, creases will appear at the sutures, and if the tension is too small, the aluminum coil will not be rolled tightly and loose layers will appear.

[0015] Furthermore, in step S3, the heat treatment is performed in a box furnace.

[0016] Furthermore, in step S3, the heat treatment temperature is 120-350°C.

[0017] Furthermore, in step S4, the uncoiling tensile stress of the tension leveler is 10-12 MPa, and the elongation is 0.2-1.0%.

[0018] Furthermore, in step S4, the shearing is that the straightening machine cuts off 150 to 180 m of head and tail waste, and the stitching cuts off 10 to 15 m, and the cutting width is 100 mm.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention limits the rolling angle and formulates reasonable cleaning, stitching, heat treatment and straightening processes, which can reduce the ingot width to a greater extent and avoid the scrapping of the ingot caused by cracks in casting. At the same time, it can also increase the weight of a single coil, reduce the amount of equipment operation, and reduce waste generation, thereby improving production efficiency, which is very beneficial to large-scale production.

[0021] 2. The cleaning and stitching steps of the present invention can increase the weight of a single coil, and the production efficiency of the annealing furnace can be doubled. At the same time, the cleaning machine, annealing furnace, and straightening machine can reduce a large number of aluminum coil lifting workers and the operation of loading and unloading the material coils, thereby reducing the amount of equipment operation.

[0022] 3. The head and tail wastes cut off during the production of the finished straightening products of the present invention are greatly reduced, and the finished product rate is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0024] Figure 1 The aluminum alloy cold-rolled coil prepared in Example 1 has slight creases at the seam-joined coil;

[0025] Figure 2 This is the ingot that was scrapped due to cracks in the production process of Comparative Example 2. DETAILED DESCRIPTION

[0026] The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0027] Example 1

[0028] In this embodiment, 5A06 alloy cold-rolled coil is prepared, the finished product width is 2600mm, the finished product thickness is 1.2mm, and the rolling mill roll surface width is 2850mm. The specific production method includes the following steps:

[0029] S1. Rolling: First, the ingot is rolled obliquely to increase the width to 2700mm, and then longitudinally rolled to a thickness of 1.2mm to obtain an aluminum coil; when the ingot is rolled obliquely, the ingot head is placed at 15 degrees to the roller; the ingot specifications used are as follows:

[0030] Ingot width = finished product width 2600mm-800mm=1800mm, ingot length = rolling mill roller surface width + 350mm=3200mm, ingot thickness = 600mm, weight = 9.26 tons.

[0031] S2. Cleaning and stitching: Put the two aluminum coils on the stitching device of the cleaning machine for stitching and rolling, the stitching device pressure is 12 MPa; the initial tensile stress of the cleaning machine is 16 MPa, and the tensile stress of the cleaning machine after stitching is set to 75% of the initial tensile stress.

[0032] S3. Heat treatment: Place the cleaned and stitched coils in a box furnace for heat treatment at a temperature of 120°C.

[0033] S4, straightening: the heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product. The unwinding tensile stress of the straightening machine is 11Mpa, and the elongation is 0.5%. The straightening machine cuts off 160m of head and tail waste, and 12m of sewing is cut off. The cutting width is 100mm.

[0034] The aluminum alloy cold-rolled coil ingot material feeding width produced in this embodiment is 1800mm, which is 30% narrower than the ingot width of normal production, and can effectively avoid the generation of ingot casting cracks, and the creases at the seams are slight. Figure 1 , the red frame shows that the coiled material prepared by the method of this embodiment has a light crease, and the crease is basically invisible.

[0035] Example 2

[0036] In this embodiment, 5A06 alloy cold-rolled coil is prepared, the finished product width is 2600mm, the finished product thickness is 1.2mm, and the rolling mill roll surface width is 2850mm. The specific production method includes the following steps:

[0037] S1. Rolling: First, the ingot is rolled obliquely to increase the width to 2700mm, and then longitudinally rolled to a thickness of 1.2mm to obtain an aluminum coil; when the ingot is rolled obliquely, the ingot head is placed at 30 degrees to the roller; the ingot specifications used are as follows:

[0038] Ingot width = finished product width 2600mm-800mm=1800mm, ingot length = rolling mill roller surface width + 350mm=3200mm, ingot thickness = 600mm, weight = 9.26 tons.

[0039] S2. Cleaning and stitching: The three aluminum coils are placed on the stitching device of the cleaning machine for stitching and winding. The pressure of the stitching device is 12 MPa. The initial tensile stress of the cleaning machine is 16 MPa. After stitching, the tensile stress of the cleaning machine is set to 75% of the initial tensile stress.

[0040] S3. Heat treatment: Place the cleaned and stitched coils in a box furnace for heat treatment at a temperature of 350°C.

[0041] S4, straightening: the heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product. The unwinding tensile stress of the straightening machine is 11Mpa, and the elongation is 0.5%. The straightening machine cuts off 170m of head and tail waste, and 12m of sewing is cut off. The cutting width is 100mm.

[0042] The aluminum alloy cold-rolled coil produced in this embodiment has no crack defects, no cracks are generated during ingot casting, and the creases at the seams are slight.

[0043] Example 3

[0044] In this embodiment, 5A06 alloy cold-rolled coil is prepared, the finished product width is 2600mm, the finished product thickness is 1mm, and the rolling mill roll surface width is 2850mm. The specific production method includes the following steps:

[0045] S1. Rolling: First, the ingot is rolled obliquely to increase the width to 2800mm, and then longitudinally rolled to a thickness of 1mm to obtain an aluminum coil; when the ingot is rolled obliquely, the ingot head is placed at 60 degrees to the roller; the ingot specifications used are as follows:

[0046] Ingot width = finished product width 2600mm - 200mm = 2400mm, ingot length = rolling mill roller surface width + 100mm = 2950mm, ingot thickness = 500mm, weight = 9.48 tons.

[0047] S2. Cleaning and stitching: The three aluminum coils are placed on the stitching device of the cleaning machine for stitching and rolling. The pressure of the stitching device is 13 MPa. The initial tensile stress of the cleaning machine is 14 MPa. After stitching, the tensile stress of the cleaning machine is set to 70% of the initial tensile stress.

[0048] S3. Heat treatment: Place the cleaned and stitched coils in a box furnace for heat treatment at a temperature of 300°C.

[0049] S4, straightening: the heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product. The unwinding tensile stress of the straightening machine is 10Mpa, and the elongation is 0.2%. The straightening machine cuts off 150m of waste material at the head and tail, and cuts off 10m of sewing, with a cutting width of 200mm.

[0050] The aluminum alloy cold-rolled coil produced in this embodiment has no crack defects, no cracks are generated during ingot casting, and the creases at the seams are slight.

[0051] Example 4

[0052] In this embodiment, 5A06 alloy cold-rolled coil is prepared, the finished product width is 2600 mm, the finished product thickness is 1.2 mm, and the rolling mill roll surface width is 2850 mm. The production method comprises the following steps:

[0053] S1. Rolling: First, the ingot is rolled obliquely to increase the width to 2750mm, and then longitudinally rolled to a thickness of 1.2mm to obtain an aluminum coil; when the ingot is rolled obliquely, the ingot head is placed at 55 degrees to the roller; the ingot specifications used are as follows:

[0054] Ingot width = finished product width 2600mm-1000mm=1600mm, ingot length = rolling mill roller surface width + 800mm=3650mm, ingot thickness = 650mm, weight = 10.17 tons.

[0055] S2. Cleaning and stitching: Put the two aluminum coils on the stitching device of the cleaning machine for stitching and rolling, the stitching device pressure is 12Mpa; the initial tensile stress of the cleaning machine is 18Mpa, and the tensile stress of the cleaning machine after stitching is set to 80% of the initial tensile stress.

[0056] S3. Heat treatment: Place the cleaned and stitched coils in a box furnace for heat treatment at a temperature of 200°C.

[0057] S4, straightening: the heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product. The unwinding tensile stress of the straightening machine is 12Mpa, and the elongation is 1.0%. The straightening machine cuts off 180m of waste material at the head and tail, and 15m of sewing is cut off. The cutting width is 150mm.

[0058] The aluminum alloy cold-rolled coil produced in this embodiment has no crack defects, no cracks are generated during ingot casting, and the creases at the seams are slight.

[0059] Comparative Example 1

[0060] In this comparative example, the existing process is used to prepare 5A06 alloy cold-rolled coil, the finished product width is 2600 mm, the finished product thickness is 1.2 mm, and the rolling mill roll surface width is 2850 mm.

[0061] The ingot specifications used are: ingot width = 2000mm, ingot length = 2700mm, ingot thickness 600mm, weight 8.7 tons. The process is to increase the width to 2700mm by horizontal rolling of the ingot, and then to 1.2mm by longitudinal rolling.

[0062] The waste weight and yield rate of each embodiment and comparative example were calculated, and the results are shown in Table 1:

[0063] Table 1

[0064]

[0065] If the weight of comparative example 1 is the same as that of embodiment 2 (weight increase 3.2 times), the total weight of waste is: 0.322×3.2+1.254×3.2=5 tons, while the total weight of waste in embodiment 2 is only 1.542 tons+1.427 tons=2.969 tons. It can be seen that the method of the present invention can improve the yield rate and production efficiency and reduce waste generation.

[0066] Comparative Example 2

[0067] In this comparative example, 5A06 alloy cold-rolled coils were prepared, with a finished product width of 2600mm, a finished product thickness of 1.2mm, and a rolling mill roll surface width of 2850mm; an ingot with a width of 2700mm, a length of 6000mm, a thickness of 600mm, and a weight of 9.26 tons was used. The ingot feeding width reached 2700mm, and crack defects were easily generated during the ingot casting process, which resulted in the scrapping of the entire ingot, and the casting difficulty was high and the success rate was low. Figure 2 This is an ingot that was scrapped due to cracks in the production process. The white line in the middle is the crack.

[0068] In summary, the present invention can reduce the width of the ingot to the greatest extent by limiting the rolling angle and formulating reasonable cleaning, suturing, heat treatment and straightening processes, thereby avoiding the scrapping of the ingot caused by cracks in the casting. At the same time, it can also increase the weight of a single coil, reduce the amount of equipment operation, reduce waste generation, and thus improve production efficiency, which is very beneficial for large-scale production. The cleaning and suturing steps of the present invention can increase the weight of a single coil, and the production efficiency of the annealing furnace can be increased exponentially. At the same time, the cleaning machine, annealing furnace, and straightening machine can reduce a large number of aluminum coil lifting workers, and the material coil loading and unloading operations, thereby reducing the amount of equipment operation. The head and tail waste cut off during the production of the straightening finished product of the present invention is greatly reduced, and the yield rate is high.

[0069] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A method for producing cold-rolled aluminum alloy coils, characterized in that: The following steps are involved: S1. Rolling: firstly, the ingot is rolled obliquely to increase the width, and then longitudinally rolled to obtain the aluminum coil; The width of the ingot = the finished product width - (200-1000) mm, the length of the ingot = the rolling mill roll surface width + (100-800) mm, and the thickness of the ingot = 500-650 mm; S2, cleaning and sewing: placing 2 to 3 aluminum coils on the sewing device of the cleaning machine for sewing and rolling, the pressure of the sewing device is 12 to 13 MPa; S3, heat treatment: heat treatment of the cleaned and stitched coils; S4, Straightening: The heat-treated coil is straightened and sheared by a straightening machine to obtain the finished product.

2. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S1, when the ingot is obliquely rolled, the ingot head is placed at an angle of 15 to 60 degrees to the rolling roller.

3. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S1, the thickness of the aluminum coil is 1 to 1.2 mm.

4. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S2, the initial tensile stress of the cleaning machine is 14-18 MPa, and the tensile stress of the cleaning machine after suturing is set to 70-80% of the initial tensile stress.

5. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S3, the heat treatment is performed in a box furnace.

6. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S3, the heat treatment temperature is 120-350°C.

7. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S4, the unwinding tensile stress of the tension leveler is 10-12 MPa, and the elongation is 0.2-1.0%.

8. The method for producing cold-rolled aluminum alloy coil according to claim 1, characterized in that: In step S4, the shearing is that the straightening machine cuts off 150-180m of head and tail waste, and the sewing machine cuts off 10-15m, and the cutting width is 100mm.

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