CN212443157U - High-speed continuous casting and rolling system for aluminum alloy thin strip - Google Patents

Abstract

The utility model discloses a high-speed continuous casting and rolling system for thin strip of aluminum alloy belongs to metallurgical processing technology field, include the smelting furnace that sets gradually along the production line, the stove that stews, preceding liquid tank, continuous casting machine, hot rolling mill, middle quick cooling device, cold rolling unit and coiling machine. The utility model discloses fused processes such as high-speed casting, continuous hot rolling, middle fast cooling, continuous cold rolling, once only accomplished from casting to cold-rolled tissue evolution. The method has high solidification speed, can produce common aluminum strips, can produce aluminum strips with high alloy content such as 5XXX, 6XXX series and the like, has the production speed of 60-100 m/min, low production energy consumption and high production rhythm, has less pollution emission and great economic benefit and social benefit, and can ensure that the rolling time from the smelting of the cast ingot to the rolling of a finished product is less than 8-12 h.

Description

High-speed continuous casting and rolling system for aluminum alloy thin strip

Technical Field

The utility model belongs to the technical field of the metallurgical processing, concretely relates to high-speed continuous casting and rolling system is taken to aluminum alloy realizes that broad width aluminum alloy takes high-speed, high-efficient manufacturing based on short flow.

Background

The automobile lightweight, new energy automobile, public transportation, aerospace, one-by-one construction and the like can greatly promote the continuous and stable increase of the using amount of the high-end aluminum alloy, and the demand of the high-end aluminum alloy is strong. Meanwhile, with global warming and environmental deterioration, metal processing industries at home and abroad are developed towards greenization, low energy consumption, low emission, short flow and high efficiency.

At present, a production method of a middle-high-end aluminum alloy thin strip is mainly based on a conventional process, and comprises the steps of casting aluminum liquid into an aluminum ingot with the thickness of 300-600 mm, cutting a head, milling a surface, heating, hot rolling and coiling, and then cold rolling, coiling and subsequent heat treatment. The time consumed from the beginning to the end of the manufacturing process is long, the production efficiency is low, the energy consumption is high, and the economic benefit needs to be improved. Meanwhile, the horizontal casting and rolling speed of the conventional aluminum alloy is about 0.8-1.2 m/min (including an inclined mode), the thickness of the product is mostly 6-10 mm, rapid solidification cannot be realized in the process, crystal grains cannot be refined, alloy structure segregation (downward) is easily caused by horizontal casting, only 1xxx series and a small number of 3xxx and 8xxx series alloy products can be generally produced, and the application of the product is limited to civil fields with low requirements on casting quality and performance, such as building decoration, packaging and the like. Similarly, the Hazelett twin-belt continuous casting and rolling technology has the typical thickness of not more than 20mm, the casting speed is about 15m/min, and the aluminum thin strip is subsequently hot rolled and coiled, so that the production variety is also limited and segregation is easy to occur. Therefore, the defects of low production speed, few production varieties and the like of the traditional casting and rolling process are urgently needed to be solved.

In order to accelerate the production efficiency, improve the product quality and shorten the process flow, a great number of attempts are made by many scientific research institutions and scientific research workers. For example, U.S. patent CN200580010951.6 by mei-ai corporation proposes a short-run high-speed method for producing thin aluminum strip, which comprises cooling a continuously cast thin aluminum alloy strip to a hot or warm rolling temperature for rolling, and performing on-line annealing or solution treatment to coil the finished product; the process flow avoids the large deformation link of cold rolling, does not obtain accumulated deformation, cannot provide initial energy accumulation for subsequent heat treatment, and is not beneficial to subsequent structure control and performance control. For another example, patent CN200810098094.5 of Chongqing university directly coils aluminum alloy strip of 1.0-3.5 mm cast and rolled at high speed, and further adjustment of the aluminum thin strip cannot be performed. For another example, northeast university patent 201910577706.7 provides a method for rapidly producing an aluminum alloy thin strip, but the production cycle is delayed through multiple uncoiling and coiling in the process, and the casting and rolling speed is 0.3-35 m/min.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model aims at providing a thin high-speed continuous casting and rolling system of taking of aluminum alloy to solve the big, inefficient, turnover cycle length of conventional long flow process area and conventional short flow process quality low side, the difficult problem such as inefficiency.

The utility model discloses a realize through following technical scheme:

the utility model provides a pair of thin high-speed continuous casting and rolling system of taking of aluminum alloy, include the smelting furnace that sets gradually along the production line, the stove that stews, preceding liquid tank, continuous casting machine, hot rolling mill, middle quick cooling device, cold rolling unit and coiling machine.

Further, the continuous casting machine is a molten pool precooling type vertical constant-diameter twin-roll casting machine, a precooling vertical plate is arranged on the edge of a molten pool, and a water-cooling casting roll is arranged at the lower part of the molten pool.

Furthermore, the molten pool is a high static pressure closed molten pool, an end side sealing structure or an insertion side sealing structure is adopted, the height of the molten pool is 100-500 mm, and a pre-cooling vertical plate arranged on the edge of the molten pool can take away 0-30% of heat of the aluminum alloy melt.

Furthermore, the double rollers of the water-cooled casting roller are horizontally arranged, a groove-shaped roller or a smooth roller is adopted, a water-cooled structure is arranged in the water-cooled casting roller, and a roller sleeve sleeved outside the water-cooled casting roller is a copper sleeve or a thin-wall carbon steel sleeve; the width of the surface of the water-cooled casting roller is 1000-2000 mm, and the diameter of the water-cooled casting roller is 500-1200 mm; the thickness of the roller sleeve is 10-70 mm; the inlet temperature of cooling water of the water-cooled casting roller is 20-33 ℃, the outlet temperature of the cooling water is 20-40 ℃, and the pressure of the cooling water is 0.2-0.5 Mpa.

Further, the continuous casting machine adopts closed casting and is provided with a flow distribution pipe immersed into a molten pool, the central height of the flow distribution pipe is 300-500 mm, the diameter of the flow distribution pipe is 150-200 mm, the length of the flow distribution pipe is 500-2000 mm, holes are uniformly formed in the flow distribution pipe, the hole opening distance is 30-80 mm, the hole opening angle is 25-40 degrees, the hole opening width is 10-15 mm, and the length is 50-100 mm.

Further, the smelting furnace, the standing furnace, the front liquid box and the continuous casting machine are sequentially connected through a chute or a runner.

Further, the system also comprises air cooling devices arranged on the vertical section of the continuous casting machine and positioned on two sides of the thin strip, and the air pressure adopted by the air cooling devices is 0.4-0.7 MPa.

Further, the system also comprises a pinch roll arranged behind the bending arc section of the continuous casting machine.

Furthermore, the system also comprises a scrap chopper and a crop shear which are arranged in front of the hot rolling mill, and a scrap chopper and a segment shear which are arranged behind the cold rolling mill.

Further, the intermediate quick cooling device adopts medium cooling.

The utility model has the advantages that:

1) the utility model discloses different with current cast-rolling integration technique, adopted cast-rolling separation technique, overcome the easy problem that ftractures of high alloy content aluminum alloy in casting process, can realize the continuous casting and rolling of high alloy content aluminum alloy.

2) The utility model discloses fused processes such as casting, warm rolling, middle quick cooling, cold rolling, once only accomplished from casting to cold-rolled tissue evolution for whole production line area is little, and whole unit length overall length is not more than 100 m.

3) The utility model discloses save processes such as semicontinuous casting, face milling, homogenization thermal treatment, intermediate annealing, the production energy consumption is low, and the energy consumption only has 1/2 ~ 1/3 of traditional handicraft.

4) The utility model discloses the casting machine has adopted thin wall carbon steel roller shell, has greatly reduced the thermal resistance, and the solidification speed can reach 1000 ℃/S and above, belongs to typical inferior rapid solidification, adapts to difficult casting alloy, for example 5XXX and 6XXX alloy. These alloys are difficult to produce on conventional cast-rolling lines.

5) The utility model discloses utilize the rapid solidification technique, the aluminum alloy fuse-element solidifies rapidly in vertical two roller casting roll district within a definite time, has reduced the tissue segregation, can realize the casting of the aluminum alloy casting of higher alloy content no main aluminum alloy even, and its tissue is even, and the crystalline grain is tiny.

6) The utility model adopts the sealing technology of the molten aluminum bath to prevent the secondary oxidation of the cast aluminum alloy solution.

7) The utility model discloses utilize the rapid solidification technique, the casting speed is fast, can reach 60 ~ 100 m/min. The annual capacity of one unit can reach more than 15-20 ten thousand tons.

8) The utility model discloses be fit for producing thin and wide aluminum alloy strip, can stably produce the aluminium casting strip within 5mm, the width can reach 1000 ~ 2000 mm.

9) The utility model discloses the production rhythm is fast, and the flow is short, and production cycle is short, is less than 8 ~ 12h from the finished rolling of smelting to the aluminium ingot.

Generally speaking, the utility model discloses a process such as clean smelting, high-speed casting, online precooling, continuous hot rolling, middle fast cooling, continuous cold rolling, online side cut, online batch have been fused in the process flow, once only accomplish from casting to cold rolling tissue evolution. The method has the advantages of small occupied area, short process flow, low investment cost, low energy consumption and emission, fine crystal grains, uniform structure, good product performance, suitability for production of common plates and medium-high-end aluminum alloy strips and the like.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and/or combinations particularly pointed out in the appended claims.

Drawings

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail with reference to the accompanying drawings, in which:

fig. 1 is the schematic diagram of the industrial production line of the present invention.

Fig. 2 is a process flow chart of the present invention.

In the figure: SMF-smelting furnace; STF-standing furnace; FLB-front tank; VCR — continuous casting machine; ACD-air cooling device; PR-pinch roll; SS 1-scrap cutter; SH 1-crop shear; HR-hot rolling mill; FC — intermediate rapid cooling device; CR 1-CRn-cold rolling mill group; SS 2-scrap cutter; SH 2-segmentation shear; DC1, DC 2-1 # and 2# coilers; T0-T6 show the temperature of the aluminum alloy strip at each stage; H0-H3 show the thickness of the aluminum alloy strip at each stage.

Detailed Description

The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can also be implemented or applied through other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention, and the features in the following embodiments and examples may be combined with each other without conflict.

Referring to the attached drawings 1 and 2, the main equipment of the high-speed continuous casting and rolling system for the aluminum alloy thin strip of the embodiment comprises a smelting furnace SMF, a standing furnace STF, a front liquid box FLB, a continuous casting machine VCR, an air cooling device ACD, a pinch roll PR, a scrap cutter SS1, a crop shear SH1, a hot rolling mill HR, an intermediate quick cooling device FC, cold rolling units CR 1-CRn, a scrap cutter SS2, a segmented shear SH2, a coiling machine DC1 and DC 2. The smelting furnace, the standing furnace, the front liquid box and the continuous casting machine are connected through a chute or a runner; the continuous casting machine is characterized in that a copper sleeve or a thin-wall steel sleeve is adopted as a casting roller outer roller sleeve, two rollers are horizontally arranged and cast up and down, the temperature of a cast aluminum alloy melt is 650-720 ℃, the casting speed is not lower than 60-100 m/min, the thickness of a cast aluminum strip is 2-5 mm, and the width of the cast aluminum strip is 1000-2000 mm; the continuous casting machine is provided with a precooling vertical plate, so that 0-30% of heat of the aluminum alloy melt can be removed, and the requirement of rapid solidification and cooling of the aluminum liquid is met; the continuous casting machine is provided with an optional air cooling device in the vertical section, the cast aluminum alloy strip can be strengthened, and the temperature of the cast aluminum strip is controlled to be 200-550 ℃ by cold air with the air pressure of 0.4-0.7 MPa in an online air cooling mode; after the pinch roll is arranged at the arc bending section of the continuous casting machine, the cast aluminum strip horizontally advances; the edge breaking shears and the end cutting shears are arranged in front of the hot rolling mill, and can be used for trimming the edge and cutting the end of the cast thin strip; the hot rolling mill is used for carrying out hot rolling or warm rolling on the cast thin strip, the temperature of the aluminum strip is controlled to be 200-550 ℃, and the reduction amount is controlled to be 5-50%; the intermediate quick cooling device is positioned between the hot rolling mill and the cold rolling mill group, the rolled thin strip is cooled by adopting a medium, and the temperature of the cooled aluminum strip is controlled to be not more than 60 ℃; the cold rolling unit can be provided with 1-3 cold rolling frames, the rolling temperature of a cold-rolled aluminum strip is not more than 60 ℃, the total deformation rate is controlled to be 30-90%, the thickness of the obtained aluminum alloy thin strip is 0.5-2 mm, the cold rolling unit is provided with a dynamic specification changing function, and cold-rolled aluminum coils with a plurality of target thicknesses are produced under the condition that the thickness of a casting blank is not changed; and a scrap shearing shear, a sectional shear and a scrap collecting device are arranged behind the cold rolling unit and are used for cutting off the cold-rolled thin strip, cutting off the edge part and coiling the scrap or breaking the scrap.

Specifically, a specified aluminum alloy ingot or electrolytic aluminum liquid is added into a smelting furnace SMF to be smelted, the metal after being smelted and degassed flows into a refining furnace STF to be further refined, then the molten metal flows into a front liquid box FLB, the molten metal is kept in a stable state in the front liquid box FLB and is continuously supplied to a continuous casting machine VCR through a chute, an aluminum thin strip from the continuous casting machine VCR passes through an optional air cooling device ACD and a pinch roll PR, passes through an optional scrap shear SS1 and a shear SH1 of a shear trimming station for edge trimming and transverse cutting, and then is sent into a hot rolling machine HR to be subjected to hot rolling or warm rolling. And (3) feeding the aluminum thin strip from the hot rolling mill into a medium-cooled intermediate quick cooling device FC, quickly cooling to a cold rolling temperature, and then feeding the aluminum thin strip into a cold rolling unit CR for cold rolling. The aluminum thin strip from the cold rolling mill is cut by scrap shear SS2 and cut by segment shear SH2 at appropriate time, and then is coiled by a coiling machine DC. In the period, the number of the smelting furnace, the refining furnace, the hot rolling mill, the cold rolling mill and the coiling mill is configured according to the capacity of the unit, the product quality requirement and the like.

The following process steps of the high-speed continuous casting and rolling system for the aluminum alloy thin strip are introduced, and the process comprises the following steps:

(a) smelting and refining: melting an aluminum alloy ingot or directly adopting electrolytic aluminum liquid to melt in a melting furnace, degassing by melting, then transferring the aluminum liquid to a standing furnace to further purify the aluminum liquid so as to obtain stable refined aluminum alloy melt, then degassing and filtering on line, and continuously conveying the qualified aluminum liquid to a subsequent continuous casting machine through a runner or a chute.

(b) Continuous casting: the refined aluminum alloy melt is continuously cast at high speed in a vertical equal-diameter twin-roll casting machine by adopting an online cooling technology, and a casting thin strip is obtained.

(c) Hot rolling or warm rolling: and (3) directly feeding the continuously cast thin strip into a hot rolling mill for rolling through a pinch roll and an optional head, tail and edge shearing device to obtain the thin strip with good plate shape and thickness precision.

(d) And (3) rapid cooling: and arranging an intermediate fast cooling device behind the hot rolling mill, and carrying out intermediate fast cooling treatment on the thin strip to obtain the thin strip meeting the cold rolling condition.

(e) Cold rolling and coiling: and directly feeding the cooled thin strip into a cold rolling mill group for cold rolling, and segmenting and coiling the cold-rolled thin strip.

By adopting the scheme, the method integrates the procedures of casting, hot rolling, intermediate quick cooling, cold rolling and the like, directly finishes the structure evolution from casting to cold rolling, greatly simplifies the process flow and greatly shortens the production period. The production energy consumption is 1/2-1/3 of the traditional process, the rolling time from the smelting of the aluminum ingot to the finished product is less than 8-12 h, and the stock turnover is not needed.

The width of the water-cooling casting roll used in the embodiment is 1000-2000 mm, the diameter is phi 500-1200 mm, the thickness of the roll sleeve is 10-70 mm, the material of the roll sleeve can be copper alloy or thin-wall carbon steel, cooling water is introduced into the casting roll, the cooling speed of the thin strip can reach 1000 ℃/S or above, the cooling water pressure of the water-cooling casting roll is 0.2-0.5 Mpa, the inlet temperature of the cooling water in the casting roll is 20-33 ℃, and the outlet temperature is 20-40 ℃. The heat transfer effect is increased, the cooling speed of the aluminum liquid is greatly improved, the casting and rolling efficiency is obviously improved, and the productivity is greatly improved. The improvement of the heat transfer effect enables the production of the aluminum alloy with a large solidification range by adopting a casting and rolling process to be feasible. The utility model discloses the improvement tissue that can be fine improves product quality. Based on the sub-rapid solidification principle, because the utility model improves the cooling rate of the aluminum liquid, the super-cooling degree is improved, the nucleation rate is increased, the growth of crystal grains is inhibited, and the original crystal grains are fine. Therefore, the utility model discloses be favorable to producing thin area of high performance aluminum alloy.

In the high-speed continuous casting process of the embodiment, a novel distributor is adopted, so that the molten aluminum uniformly enters the vertical equal-diameter double-roller casting machine through the distributor. The central height of the flow distribution pipe of the flow distributor is 300-500 mm, the diameter of the flow distribution pipe is 150-200 mm, the length of the flow distribution pipe is 500-2000 mm, the flow distribution pipe is uniformly perforated, the distance between the holes is 30-80 mm, the angle of the holes is 25-40 degrees, the width of the holes is 10-15 mm, and the length of the holes is 50-100 mm. When the pouring device is used for vertical pouring, the flow distributor is inserted below the liquid level for pouring, and the position of the water outlet is lower than the position below the liquid level, so that the liquid level is stable. The whole pouring process adopts a closed pouring mode of high static pressure, air is prevented from entering, the oxidation of aluminum alloy is effectively prevented, and the defect of casting and rolling caused by the fact that oxide skin enters molten aluminum is avoided; and (4) adopting high static pressure for pouring, and controlling the height of a molten pool to be 100-500 mm.

In the embodiment, the hot rolling mill HR is arranged behind the continuous casting machine VCR, and the aluminum thin strip from the continuous casting machine VCR is subjected to hot rolling or warm rolling, so that cracking of high-alloy-content aluminum alloys such as 5XXX and 6XXX due to large casting stress in the casting and cooling process is prevented, a casting machine and hot rolling combination mode is adopted, casting and rolling separation is realized, cracks of the rolled aluminum strip are avoided, and the guarantee is provided for producing the high-alloy-content aluminum thin strip by a continuous casting and rolling process.

The utility model discloses to smelt, casting, hot rolling, fast cold, cold rolling and have fused together, need not the stock turnover, once only accomplished the production of aluminium foil coil of strip. The cast aluminum thin strip is directly rolled in a cold rolling unit after hot rolling or warm rolling, and then is coiled by a coiling machine. The middle adopts a medium quick cooling mode, and the medium is one or a combination of more of water, air or water mist; the intermediate quick cooling device is arranged behind the hot rolling mill, and the aluminum thin strip coming out of the hot rolling mill is quickly cooled, so that the growth of internal crystal grains is prevented.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and it is obvious that those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (10)

1. The high-speed continuous casting and rolling system for the aluminum alloy thin strip is characterized by comprising a smelting furnace, a standing furnace, a front liquid box, a continuous casting machine, a hot rolling machine, an intermediate quick cooling device, a cold rolling unit and a coiling machine which are sequentially arranged along a production line.

2. The system of claim 1, wherein the continuous casting machine is a vertical constant diameter twin roll casting machine of a molten bath precooling type, and the edge of the molten bath is provided with precooling vertical plates, and the lower part of the molten bath is provided with water-cooled casting rolls.

3. The high-speed continuous casting and rolling system for the aluminum alloy thin strip according to claim 2, wherein the molten pool is a high static pressure closed molten pool, an end side sealing structure or an insertion side sealing structure is adopted, the height of the molten pool is 100-500 mm, and a pre-cooling vertical plate arranged on the edge of the molten pool can take away 0-30% of heat of the aluminum alloy melt.

4. The high-speed continuous casting and rolling system for the thin aluminum alloy strip according to claim 2, wherein the two rollers of the water-cooled casting roller are horizontally arranged, a groove-shaped roller or a smooth roller is adopted, a water-cooled structure is arranged in the water-cooled casting roller, and a copper sleeve or a thin-wall carbon steel sleeve is sleeved outside the water-cooled casting roller; the width of the surface of the water-cooled casting roller is 1000-2000 mm, and the diameter of the water-cooled casting roller is 500-1200 mm; the thickness of the roller sleeve is 10-70 mm; the inlet temperature of cooling water of the water-cooled casting roller is 20-33 ℃, the outlet temperature of the cooling water is 20-40 ℃, and the pressure of the cooling water is 0.2-0.5 Mpa.

5. The high-speed continuous casting and rolling system for the thin aluminum alloy strip according to any one of claims 2 to 4, wherein the continuous casting machine adopts closed casting, is provided with a flow distributor immersed into a molten pool, and has a central height of 300 to 500mm, a diameter of 150 to 200mm, a length of 500 to 2000mm, and holes uniformly formed on the flow distributor, wherein the hole pitch is 30 to 80mm, the hole angle is 25 to 40 °, the hole width is 10 to 15mm, and the length is 50 to 100 mm.

6. The high-speed continuous casting and rolling system for thin aluminum alloy strip according to claim 1, wherein the smelting furnace, the standing furnace, the front liquid box and the continuous casting machine are connected in sequence through a chute or a runner.

7. The high-speed continuous casting and rolling system for the thin aluminum alloy strip according to claim 1, further comprising air cooling devices arranged on the vertical section of the continuous casting machine and located on two sides of the thin aluminum alloy strip, wherein the air pressure adopted by the air cooling devices is 0.4-0.7 MPa.

8. The system of claim 1 further comprising pinch rolls positioned after the curved segment of the continuous caster.

9. The high-speed continuous casting and rolling system for the thin aluminum alloy strip according to claim 1, further comprising edge breaking shears and head cutting shears arranged in front of the hot rolling mill, and edge breaking shears and sectional shears arranged behind the cold rolling mill.

10. The high-speed continuous casting and rolling system for the thin aluminum alloy strip according to claim 1, wherein the intermediate rapid cooling device is cooled by a medium.

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