Aluminum alloy thin strip vertical casting and rolling system and process

Abstract

The present application relates to the technical field of aluminum alloy cast rolling, in particular to an aluminum alloy thin strip vertical cast rolling system and process, comprising at least one pair of horizontally placed cast rolling rollers and side sealing plates located on both sides of the cast rolling rollers, and a V-shaped area between the side sealing plates and the top of the cast rolling rollers collectively forming a cast rolling area molten pool; an adjustable height feeding nozzle is arranged above the cast rolling area molten pool, the feeding nozzle comprises a heat preservation layer, a casting nozzle and a temperature control assembly, the heat preservation layer is located outside the casting nozzle, the temperature control assembly is located between the heat preservation layer and the casting nozzle, the casting nozzle comprises a liquid storage cavity and a discharge port, the discharge port has an elongated structure, the cross-sectional width of the discharge port is 5-10 mm, and the length of the discharge port is 130-150 mm. The present application can solve the technical problem that the system balance cannot be quickly maintained during the existing aluminum alloy production process, resulting in low overall cast rolling speed.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy casting and rolling technology, specifically to a vertical casting and rolling system and process for aluminum alloy thin strips. Background Technology

[0002] Currently, in the field of aluminum alloy casting and rolling, the thickness of cast aluminum alloy coils is generally in the range of 5-8mm. People hope that the coil thickness is as thin as possible to reduce the number of cold rolling passes in subsequent processes. However, the thinner the cast coil, the greater the technical difficulty and the more limiting conditions there are. At present, there are three main types of aluminum alloy casting and rolling equipment: bottom pouring, horizontal, and inclined. However, none of these three casting and rolling methods can overcome the influence of gravity on the aluminum liquid entering the casting and rolling zone. The heat transfer and flow of the liquid inside the molten pool are different in the two crystallization shells, resulting in inconsistent crystallization rates on the two sides of the billet shell. The grain orientation is biased towards the lower shell, which in turn makes the cast strip structure uneven, the surface quality of the cast strip unstable and has differences between the two sides, resulting in poor performance and making it unsuitable for direct subsequent rolling processing.

[0003] To address this problem, the inventors, after careful consideration, decided to apply vertical casting to aluminum alloy processing, utilizing gravity to ensure uniform distribution of the molten aluminum. Patent document CN101269406B also provides a continuous casting process for aluminum alloy strip billets, where two casting rolls are placed horizontally, ensuring uniform and symmetrical cooling of the molten aluminum alloy. This results in a consistent surface morphology of the liquid film in the condensation zone, leading to a uniform microstructure in the resulting strip billet, which is beneficial for subsequent processing. However, the inventors discovered that the above casting process still suffers from the following technical problems:

[0004] 1. The molten pool structure is large and deep, making it impossible to interfere with the flow field and temperature of the molten pool from the outside. The only way to control it is by changing the melt temperature and the cooling intensity of the casting rolls. However, this method is not conducive to the stable and precise adjustment of the balance between heat transfer, flow, solidification and hot rolling of the aluminum liquid. The main reason is that the temperature of the molten aluminum pool plays a crucial role in the process of casting and rolling aluminum liquid into aluminum strip. When the casting and rolling speed increases, the aluminum liquid flows faster in the molten pool. If the temperature of the melt is too high at this time, it will cause the aluminum liquid to leak before it can solidify. When the temperature of the molten pool is too low, the aluminum liquid is more likely to solidify in the molten pool. Therefore, the existing casting and rolling speed is greatly limited.

[0005] 2. Similarly, because the existing molten pool is not convenient for adjusting the flow of aluminum liquid, crystallization and solidification, the existing technology cannot produce ultra-thin aluminum strips with a thickness of less than 1 mm. Summary of the Invention

[0006] The present invention aims to provide a vertical casting and rolling system and process for aluminum alloy strips, which can solve the technical problem that the existing aluminum alloy production process cannot quickly maintain system balance, resulting in low overall casting and rolling speed.

[0007] To achieve the above object, the present application adopts the following technical scheme:

[0008] The vertical casting-rolling system of aluminum alloy thin strip comprises at least one pair of horizontally placed casting-rolling rolls and side sealing plates located on both sides of the casting-rolling rolls, and a V-shaped area between the top of the casting-rolling rolls and the side sealing plates on both sides together encloses a casting-rolling area molten pool; an adjustable height feeding nozzle is arranged above the casting-rolling area molten pool, the feeding nozzle comprises a heat preservation layer, a casting nozzle and a temperature control assembly, the heat preservation layer is located outside the casting nozzle, the temperature control assembly is located between the heat preservation layer and the casting nozzle, the casting nozzle comprises a liquid storage cavity and a discharge port, the discharge port has an elongated structure, the cross-sectional width of the discharge port is 5-10mm, and the length of the discharge port is 130-150mm.

[0009] Technical principles and beneficial effects:

[0010] By arranging the special feeding nozzle with the temperature control assembly, the present application can realize real-time heating or cooling according to the temperature condition near the casting-rolling area (molten pool), ensure that the aluminum liquid in the molten pool is always in a semi-molten state, maintain the dynamic balance in the casting-rolling process, and thus realize continuous casting. In other words, by adjusting the temperature of the aluminum liquid in the feeding nozzle, the temperature of the aluminum liquid in the shell forming area can be intervened, and the length of the shell forming area (the aluminum liquid immediately solidifies into a crystalline state when contacting the casting-rolling roll from a molten state) is controlled indirectly. When the casting-rolling speed increases, the aluminum liquid flow speed becomes faster, which causes the length of the shell forming area to decrease excessively. If the length of the shell forming area decreases to a length at which the cooling liquid inside the casting-rolling roll cannot take away the heat released by the crystallization, the aluminum liquid cannot solidify in time between the casting-rolling roll seals, and the casting mill will appear "leakage", which causes the casting-rolling to be unable to continue. At this time, the temperature control assembly in the feeding nozzle is adjusted to reduce the temperature of the aluminum liquid, increase the cooling intensity, increase the amount of aluminum liquid in the feeding nozzle that enters the semi-solid crystalline state, take away the heat released by the crystallization that the casting-rolling roll cannot take away in time, and keep the aluminum liquid in the molten pool in a molten state, so as to ensure the continuous casting.

[0011] On the basis of the above-mentioned temperature control assembly, the present application designs the cross-sectional width of the discharge port of the casting nozzle to be 5-10mm and the length to be 130-150mm. This design structure further meets the conditions for artificially interfering with the aluminum liquid that forms the molten pool between the two casting-rolling rolls, makes the amount, temperature and flow speed of the aluminum liquid in the space of the discharge port of the casting nozzle artificially interfered sensitive, the response time after the interference is short, and the controllable purpose is truly achieved. Furthermore, the casting-rolling speed is always kept at 120-150m / min to realize stable production, and the problem of low casting-rolling speed is solved.

[0012] The present application can select two modes of submergence type or infusion type according to actual conditions by setting the height of the feeding nozzle as adjustable, only need to adjust the fixed height of the feeding nozzle or the distance between the nozzle outlet and the roll gap, and then change the depth of the molten pool; in special cases, the molten pool can only exist in the space of the liquid storage cavity and the nozzle outlet, and the aluminum liquid flows out of the nozzle outlet under the action of gravity and the static pressure of the aluminum liquid above, and then forms the shell zone with the casting roll, and then continuously forms the rolling zone.

[0013] The present application horizontally places two casting rolls, uses the uniform gravity distribution to make the crystallization rate of the two sides of the aluminum strip almost the same, the internal crystallization grain orientation of the product is basically the same, the casting mill obtains more favorable rolling conditions (low deformation resistance) for hot rolling, and the thickness of the coiled material is thinned; in addition, the feeding nozzle can real-time adjust the molten pool, not only realizes the coiled material with thinner thickness and higher production efficiency, but also improves the internal organization of the coiled material (fast crystallization speed, grain refinement), and the performance of the finished product can be comparable to hot rolled material.

[0014] Further, the width of the cross section of the outlet is 6mm, and the length is 140mm; the size is the optimal value of the cross section of the outlet of the casting roll for 1 series aluminum alloy, when the cross-sectional area of the outlet is in the above range, and the temperature of the aluminum liquid is adjusted by the temperature control assembly, the aluminum liquid is always in a molten state during the casting process, and the aluminum strip with a thickness of less than 1mm can be produced.

[0015] Further, the side sealing plate comprises a two-layer structure, and a heating pipe and a temperature sensor are arranged between the two-layer structure.

[0016] Beneficial effects: by arranging the heating pipe and the temperature sensor in the side sealing plate, the temperature of the side aluminum liquid and the crystallization temperature can be intervened, the problem of long crystallization solidification zone caused by low temperature of the upper side of the axial shell zone can be solved by increasing the temperature of the side sealing plate; because in the whole casting area, the temperature of the two sides close to the side sealing plate is easy to lose, and the crystallization solidification of the other parts is earlier, the crystallization solidification zone of the coiled material is long, the deformation resistance of the casting roll is increased, the casting speed is seriously affected, the casting force is unevenly distributed along the transverse (axial) direction, and the smooth rolling of the coiled material is affected, such as edge cracking and edge shape control defects; in the rolling process, the temperature of the heating pipe is controlled in the range of 380-390℃, which can ensure the continuous casting, and avoid the problem of aluminum strip cracking.

[0017] Further, the temperature control assembly is at least two groups, and is arranged on both sides of the cross section of the outlet, and each temperature control assembly comprises a heater and a cooling pipe; the temperature near the casting area can be adjusted in real time by the temperature control assembly according to the casting strip.

[0018] Further, the heat preservation layer is made of silicon-aluminum fiber plate, and the nozzle is made of red copper.

[0019] Beneficial effects: the silicon-aluminum fiber plate has the advantages of light weight, high temperature resistance, good thermal stability, low thermal conductivity, small heat capacity, good resistance to mechanical vibration, small thermal expansion, good heat insulation performance, etc., which can effectively avoid heat dissipation of the aluminum liquid in the liquid storage cavity; the red copper has good electrical conductivity, thermal conductivity, ductility, deep drawability and corrosion resistance, which can effectively conduct heat, resist heat friction and high temperature, and is not easy to deform.

[0020] Further, one side of the side sealing plate in contact with the aluminum liquid is made of a composite plate made of red copper and graphite, and the other side is made of a silicon-aluminum fiber plate.

[0021] Further, the distance between the discharge port of the nozzle and the midpoint of the roll gap is 7.3 cm.

[0022] The aluminum alloy thin strip vertical casting and rolling process adopts an aluminum alloy thin strip vertical casting and rolling system for processing, mainly including the following steps:

[0023] S1: preheat the feeding nozzle to 130-160℃, preheat the side sealing plate to 420-450℃, and preheat the casting and rolling roller to 60-90℃;

[0024] S2: place a lead-out plate on the outlet side of the casting and rolling roller and apply a casting and rolling roller pre-tightening force, inject 680-690℃ aluminum liquid into the feeding nozzle, start the casting and rolling roller to slowly rotate, and the rotation speed of the casting and rolling roller is 0.03-0.15m / min;

[0025] S3: remove the lead-out plate in S2 to obtain a thicker aluminum strip blank, the thickness of the thicker aluminum strip blank is 1.8-2.5mm, increase the temperature of the liquid storage cavity of the feeding nozzle to 665-675℃, at the same time, reduce the roll gap between the two casting and rolling rollers, the roll gap between the two casting and rolling rollers is 0.6-1.0mm, and increase the rotation speed of the casting and rolling roller, and the thinner aluminum strip blank is cast and rolled;

[0026] S4: after the aluminum strip blank leaves the casting and rolling roller, the material is collected through the coiling mechanism to establish the coiling tension of the aluminum strip blank.

[0027] Further, when the thinner aluminum strip blank is cast and rolled in S3, the rotation speed of the casting and rolling roller is 120-150m / min, the cooling water temperature of the casting and rolling roller is 25-15℃, the flow is 230t / H, the pressure is 3-5bar, the temperature of the liquid storage cavity of the feeding nozzle is 665-675℃, and the temperature of the side sealing plate is maintained at 380-390℃; the rolling force of the casting mill is 1800-2500t, and the rolling torque is 450-550KN.M.

[0028] Further, the thickness of the thinner aluminum strip blank is 0.8-1.2mm.

[0029] Beneficial effects: By adopting the above casting and rolling system and process, aluminum strips with a thickness of 0.8 mm can be produced, and the casting and rolling speed can reach 120-150 m / min. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the casting and rolling equipment of the present invention;

[0031] Figure 2 This is a schematic diagram of the feed nozzle of the present invention;

[0032] Figure 3 This is a schematic diagram of the side sealing plate of the present invention;

[0033] Figure 4 for Figure 3 Side sectional view of the middle side panel. Detailed Implementation

[0034] The following detailed description illustrates the specific implementation method:

[0035] The markings in the accompanying drawings include: aluminum liquid flow channel 1, side sealing plate 2, second layer structure 21, heating tube 22, first layer structure 23, first temperature sensor 24, feeding nozzle 3, insulation layer 31, casting nozzle 32, liquid storage chamber 321, discharge port 322, heater 33, cooling tube 34, second temperature sensor 35, casting roll 4, pinching and turning roller 5, turning pressure roller 6, pinching roller 7, feeding roller 8, shearing machine 9, uncoiling trolley 10, coiler 11, width B, length L.

[0036] Example

[0037] like Figures 1-4 As shown, the vertical casting and rolling system for aluminum alloy strip includes two horizontally placed casting rolls 4, side sealing plates 2, and a height-adjustable feed nozzle 3. The casting rolls 4 consist of roll sleeves, roll cores, and cooling water channels. The roll sleeves are in contact with the liquid metal on the outer layer and act as a water-cooled crystallizer during the casting and rolling process. After the liquid metal is injected between the casting rolls 4, it is cooled, crystallized, and deformed until it becomes a metal strip blank with the required cross-sectional shape. There are two side sealing plates 2, which are used to close the two sides of the casting rolls 4. Specifically, the side sealing plates 2 are installed between the V-shaped concave arcs formed on the upper part of the two casting rolls 4 by a support frame, and their lower surfaces maintain a gap of 0.05-0.1mm with the surface of the casting rolls 4, and their relative positions with the casting rolls 4 remain unchanged at all times. The V-shaped area at the top of the two casting rolls 4 and the two side sealing plates 2 together form the molten pool of the casting zone. According to the actual use needs, the distance between the two side sealing plates 2 can be adjusted along the axial direction of the casting rolls 4 to obtain aluminum strips of different widths.

[0038] In this embodiment, the specific structure of the side sealing plate 2 is as follows: Figures 3-4As shown, the side sealing plate 2 comprises two layers of structure, i.e. a first layer of structure 23 and a second layer of structure 21, and a heating pipe 22 and a first temperature sensor 24 are arranged between the two layers of structure. Specifically, the side of the side sealing plate 2 contacting the molten aluminum is the first layer of structure 23, which is made of a composite plate made of red copper and graphite, and the second layer of structure 21 is made of a silicon-aluminum fiber plate, which mainly plays a heat preservation role. In the rolling process of the present embodiment, the temperature of the side sealing plate 2 is maintained at 380-390°C, and when the temperature reaches the above range, the heating is stopped, and when the temperature is lower than the above range, the heating is automatically started to ensure that the crystallization and solidification of the edge portion of the molten aluminum meet the requirements of high-speed rolling.

[0039] The feeding nozzle 3 of the present embodiment is vertically arranged above the roll gap of the two casting and rolling rollers 4 through a mounting plate. A strip-shaped hole is vertically arranged on the upper portion of the feeding nozzle 3, and a threaded hole is arranged on the mounting plate. When it is necessary to adjust the height of the feeding nozzle 3, the screw is loosened, and after the height of the feeding nozzle 3 is adjusted, the screw is tightened to realize fixation and positioning (in other embodiments except the present embodiment, the distance between the feeding nozzle 3 and the casting and rolling roller 4 can also be adjusted by adjusting the height of the mounting plate). The specific structure of the feeding nozzle 3 is shown in Figure 2 As shown, the feeding nozzle comprises a heat preservation layer 31, a casting nozzle 32 and a temperature control assembly. The heat preservation layer 31 is located outside the casting nozzle 32, and the temperature control assembly is located between the heat preservation layer 31 and the casting nozzle 32. Specifically, the heat preservation layer 31 is made of a silicon-aluminum fiber plate, and the casting nozzle 32 is made of red copper. The casting nozzle 32 comprises a liquid storage cavity 321 and a discharge port 322. The discharge port 322 of the casting nozzle 32 has an elongated structure, and the cross-sectional width B thereof is 5-10 mm, and the length L thereof is 130-150 mm. In the present embodiment, the cross-sectional width B of the discharge port 322 is 6 mm, and the length L thereof is 140 mm. The discharge port 322 is 7.3 cm away from the midpoint of the roll gap. In the present embodiment, the roll diameter of the casting and rolling roller 4 is 800 mm. In the present embodiment, the temperature control assembly comprises four groups. Two groups are arranged on both sides of the discharge port 322, and the other two groups are arranged on both sides of the liquid storage cavity 321 of the casting nozzle 32. Each temperature control assembly comprises a heater 33 and a cooling pipe 34. Specifically, the heater 33 and the cooling pipe 34 are inlaid between the heat preservation layer 31 and the casting nozzle 32 through a red copper plate. In addition, a second temperature sensor 35 is arranged on the lower portion of both sides of the discharge port 322.

[0040] As shown in Figure 1As shown, the cast-rolling system of the present application further comprises a coiling mechanism, which comprises a pinch-turning roller 5, a turning pressure roller 6, a pinch roller 7, a feeding roller 8 and a coiler 11 connected in sequence, wherein the pinch-turning roller 5 is located below the roll gap of the two cast-rolling rollers 4, and a plate shearing machine 9 for shearing the aluminum strip is further arranged behind the feeding roller 8; in particular in use, the aluminum strip blank comes out of the roll gap of the cast-rolling rollers 4, falls naturally under the action of gravity and the rolling of the cast-rolling rollers 4, changes direction after the pinch-turning roller 5 and the turning pressure roller 6, and then is pulled by the pinch roller 7, the head of the aluminum strip is sheared by the plate shearing machine 9, and is guided to the nip of the coiler 11 by the uncoiling trolley 10, or under the action of the coiler, the coiler 11 starts to coil the aluminum strip blank, establishes the coiling tension, and continuously coils until the whole coil is completed.

[0041] The present application further discloses an aluminum alloy thin strip vertical cast-rolling process, which is processed by the above-mentioned aluminum alloy thin strip vertical cast-rolling system, can produce an ultra-thin aluminum strip with a thickness less than 1 mm, and the cast-rolling speed can reach 120-150 m / min, and mainly comprises the following steps:

[0042] S1: the oven or the heater 33 of the feeding nozzle 3 is preheated to 130-160℃, the heating pipe 22 in the side sealing plate 2 is preheated to 420℃-450℃ (when starting to work, the heat loss of the side sealing plate is large, so the side sealing plate needs a higher temperature when preheating), and the two cast-rolling rollers 4 are preheated to 60-90℃ by adopting the hot spraying graphite mode.

[0043] S2: when the system preheating reaches the temperature in S1, the lead-out plate is placed at the outlet side of the cast-rolling roller 4 and the pre-tightening force of the cast-rolling roller 4 is applied, the aluminum liquid with a temperature of 680-690℃ is injected into the feeding nozzle 3 through the aluminum liquid flow tank 1, and the cast-rolling roller 4 is started to rotate slowly, wherein the rotating speed of the cast-rolling roller 4 is 0.03-0.15 m / min.

[0044] S3: the drawing plate in S2 is removed to obtain a thicker aluminum strip blank, the thickness of the thicker aluminum strip blank is 1.8-2.5 mm, then the temperature of the liquid storage cavity 321 of the feeding nozzle 3 is increased to 665-675 ℃ to make up for the temperature loss of the vertical plate, at the same time, the roll gap between the two casting and rolling rollers 4 is adjusted, and the rotating speed of the casting and rolling rollers 4 is increased, and the thinner aluminum strip blank is cast and rolled. At this time, the roll gap between the casting and rolling rollers 4 is 0.6-1.0 mm, the rotating speed of the casting and rolling rollers 4 is 120-150 m / min, the cooling water temperature of the casting and rolling rollers 4 is 25-15 ℃, the flow is 230 t / H, the pressure is 3-5 bar, the temperature of the liquid storage cavity 321 of the feeding nozzle 3 is kept at 665-675 ℃, and the temperature of the side sealing plate 2 is maintained at 380-390 ℃. In the embodiment, the thickness of the thinner aluminum strip blank is 0.8-1.2 mm, and the rolling force of the casting and rolling machine is 1800-2500 t, and the rolling moment is 450-550 KN.M. These equipment parameters are for casting and rolling 1 series aluminum alloy, and the casting and rolling equipment parameters of other series aluminum alloy are different.

[0045] S4: after the aluminum strip blank leaves the casting and rolling rollers 4, the material is collected through the coiling mechanism to establish the coiling tension of the aluminum strip blank.

[0046] When the above casting and rolling process is adopted, various parameters in the casting and rolling area can be manually adjusted by the operator at the initial stage of casting and rolling, when the casting and rolling reaches the preset thickness and speed of the aluminum strip coil, the intelligent program controller can be started to enable the intelligent controller to automatically manage the process parameters in the casting and rolling process until the entire casting and rolling coil production process is completed.

[0047] Taking the casting and rolling 1 series aluminum alloy as an example, the feeding nozzle 32 is provided with an elongated structure, the cross-sectional size of the feeding outlet 322 is controlled, the temperature of the feeding outlet 322 is adjusted in time during the casting and rolling process, the molten aluminum in the casting and rolling area is kept in a molten state, and the super-thin aluminum strip with a thickness less than 1 mm can be stably produced at a high speed of 120-150 m / min; under the same casting and rolling conditions, after the cross-sectional size of the feeding outlet and the temperature of the feeding outlet are changed, the aluminum strip thickness, the casting and rolling speed and the casting and rolling state are shown in the following table 1:

[0048] Table 1: cross-sectional size of feeding outlet and temperature change parameter table of feeding outlet in different embodiments and comparative examples under the same casting and rolling conditions

[0049]

[0050] Note: due to the deviation of the temperature measuring instrument, the temperature in the table is rounded by correction.

[0051] As can be seen from Example 1, when the cross-sectional size of the discharge port is taken as the minimum value (5 mm in width and 130 mm in length) and the temperature of the discharge port is the lowest at 665 ℃, the thickness of the rolled aluminum strip is 1.35 mm, but the rolling speed is limited, and the maximum rolling speed is 120 m / min; if the rolling speed is increased under this temperature condition, the crystallization speed of the aluminum liquid becomes fast, the deformation resistance of the aluminum liquid increases when it contacts the casting roller to be formed, and the problem of strip breakage is prone to occur, resulting in discontinuous rolling.

[0052] As can be seen from Example 2, when the cross-sectional width of the discharge port is 6 mm, the length is 140 mm, and the temperature of the discharge port is 670 ℃, the thickness of the cast-rolled aluminum strip can be 0.8-1 mm, and the cast-rolling speed can be stabilized in the range of 120-150 m / min.

[0053] As can be seen from Example 3, when the cross-sectional size of the discharge port is taken as the maximum value (10 mm in width and 150 mm in length) and the temperature of the discharge port is the highest at 675 ℃, the thinnest thickness of the cast-rolled aluminum strip can reach 0.7 mm, but the cast-rolling speed is limited, and the maximum cast-rolling speed is 120 m / min; if the cast-rolling speed is increased under this temperature condition, the problem of liquid leakage will occur in the cast-rolling process because the aluminum liquid cannot solidify in time, thereby resulting in discontinuous cast-rolling.

[0054] In summary, as can be seen from Examples 1-3, the cross-sectional size of the discharge port and the temperature of the discharge port will affect the cast-rolling speed and the thickness of the aluminum strip, and the main reason is that the crystallization rate of the aluminum liquid, the discharge port flow and the temperature of the discharge port are not matched, thereby causing problems such as liquid leakage or strip breakage; therefore, in order to stably produce aluminum strips with a thickness of less than 1 mm at a speed of 120-150 m / min, it is necessary to strictly control the cross-sectional size of the discharge port and the temperature of the discharge port so as to match the crystallization rate of the aluminum liquid.

[0055] As can be seen from Comparative Examples 1-2, when the cross-sectional width of the discharge port is 3 mm, the feeding amount of the discharge port is insufficient, and the cast-rolling speed is limited, and the maximum cast-rolling speed is 60 m / min; when the cross-sectional width of the discharge port is 12 mm, due to the temperature limitation of the discharge port, the deformation resistance of the aluminum strip increases when the rolling speed is increased, and the problem of strip breakage is prone to occur, and the rolling process is discontinuous.

[0056] As can be seen from Comparative Examples 3-4, when the cross-sectional length of the discharge port is 120 mm, the temperature control component of the discharge port has weak regulation, and when the rolling speed is increased, the rolling process will be unstable, thereby causing large fluctuations in the thickness of the aluminum strip and inconsistency of the aluminum strip; when the cross-sectional length of the discharge port is 160 mm, the temperature control component of the discharge port has too strong regulation, and when the speed is increased, the rolling process will still be unstable, and the problem of inconsistency in the thickness of the aluminum strip will occur.

[0057] From the comparative example 5-6, when the temperature of the discharge port is 660℃, the rolling speed is limited, the maximum speed is 102m / min, the rolling current of the casting and rolling machine increases, i.e. the deformation resistance reaches the limit of the equipment; when the temperature of the discharge port is 680℃, the aluminum liquid is in liquid state in the rolling pool area, and the aluminum liquid cannot solidify in time during rolling, resulting in liquid leakage and stopping of rolling.

[0058] In summary, the comparative examples 1, 4 and 5 can roll the aluminum strip with a thickness less than 1mm, but the rolling speed is greatly limited, the strip is easy to break during rolling, resulting in discontinuous production or inconsistent thickness of the rolled aluminum strip, and the problem of some parts being thick and some parts being thin; therefore, only when the cross-sectional size of the discharge port, the temperature of the discharge port and the speed of the casting and rolling are in a balanced state, the aluminum strip with a thickness less than 1mm can be continuously and stably produced.

[0059] The above is only an embodiment of the present application, and the well-known specific technical solutions and / or common knowledge of characteristics in the scheme are not described in detail. It should be noted that for those skilled in the art, without departing from the technical solutions of the present application, a number of modifications and improvements can be made, which should also be considered as the protection scope of the present application, and these will not affect the effect of the implementation of the present application and the practicality of the patent. The protection scope of the present application should be subject to the content of its claims, and the specific implementation mode and the like in the specification can be used to explain the content of the claims.

Claims

1. A vertical casting and rolling system for aluminum alloy thin strips, characterized in that, It includes at least one pair of horizontally placed casting rolls and side sealing plates on both sides of the casting rolls. The V-shaped area between the side sealing plates and the top of the casting rolls together forms a molten pool in the casting zone. Above the molten pool in the casting zone, there is a height-adjustable feed nozzle. The feed nozzle includes an insulation layer, a casting nozzle, and a temperature control component. The insulation layer is located on the outside of the casting nozzle, and the temperature control component is located between the insulation layer and the casting nozzle. There are at least two sets of temperature control components, which are arranged on both sides of the outlet of the casting nozzle. Each temperature control component includes a heater and a cooling pipe. The casting nozzle includes a liquid storage chamber and a discharge port. The discharge port has a slender structure with a cross-sectional width of 5-10 mm and a discharge port length of 130-150 mm. The temperature of the liquid storage chamber of the feed nozzle is maintained at 665-675℃.

2. The vertical casting and rolling system for aluminum alloy thin strips according to claim 1, characterized in that: The discharge port of the casting nozzle has a cross-sectional width of 6mm and a length of 140mm.

3. The vertical casting and rolling system for aluminum alloy thin strips according to claim 1, characterized in that: The side sealing plate comprises a two-layer structure, with a heating tube and a temperature sensor disposed between the two layers.

4. The vertical casting and rolling system for aluminum alloy thin strips according to any one of claims 1-3, characterized in that: The insulation layer is made of silicon-aluminum fiberboard, and the casting nozzle is made of copper.

5. The vertical casting and rolling system for aluminum alloy thin strips according to claim 3, characterized in that: The side of the side sealing plate that contacts the molten aluminum is made of a composite plate of copper and graphite, while the other side is made of silicon-aluminum fiberboard.

6. The vertical casting and rolling system for aluminum alloy thin strips according to claim 5, characterized in that: The discharge port is 7.3 cm away from the midpoint of the roller gap.

7. A vertical casting and rolling process for aluminum alloy thin strips, wherein the aluminum alloy thin strips are processed using the vertical casting and rolling system as described in any one of claims 1-3, 4, and 5-6, characterized in that, The main steps include the following: S1: Preheat the feed nozzle to 130-160℃, the side sealing plate to 420-450℃, and the casting roll to 60-90℃; S2: Place the lead-out plate on the exit side of the casting roll and apply the pre-tightening force to the casting roll. Inject molten aluminum at 680-690℃ into the feed nozzle, start the casting roll and make it rotate slowly. The speed of the casting roll is 0.03-0.15m / min. S3: Remove the lead plate from S2 to obtain a thicker aluminum strip billet with a thickness of 1.8-2.5mm. Gradually increase the temperature of the feed nozzle from the original temperature to maintain the temperature in its storage chamber at 665-670℃. At the same time, reduce the gap between the two casting rolls to 0.6-1.0mm and increase the speed of the casting rolls to cast a thinner aluminum strip billet. S4: After the aluminum strip leaves the casting rolls, it is collected by the coiling mechanism to establish the coiling tension of the aluminum strip.

8. The vertical casting and rolling process for aluminum alloy thin strips according to claim 7, characterized in that: When stabilizing the casting and rolling of thin aluminum strip in S3, the rotational speed of the casting roll is 120-150 m / min, the cooling water temperature of the casting roll is 25-15℃, the flow rate is 230 t / H, the pressure is 3-5 bar, the temperature of the liquid storage chamber in the feed nozzle is 665-675℃, and the temperature of the side sealing plate is maintained at 380-390℃; the rolling force of the casting and rolling mill is 1800-2500 t, and the rolling torque is 450-550 KN.M.

9. The vertical casting and rolling process for aluminum alloy thin strips according to claim 8, characterized in that: The thickness of the thinner aluminum strip blank is 0.8-1.2mm.

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