Aluminum alloy twin-roll strip continuous casting equipment and flow distribution system

Abstract

The application discloses an aluminum alloy double-roller thin strip continuous casting equipment and a flow distribution system, and aims to continuously and stably distribute the molten aluminum to the molten pool for a long time, thereby improving the casting and rolling quality of the thin strip. To this end, the aluminum alloy double-roller thin strip continuous casting flow distribution system comprises a buffer cavity and a flow distribution cavity, the lower end of the flow distribution cavity is immersed in a stable molten pool formed between two crystallization rollers, the upper end of the flow distribution cavity is in communication with a liquid outlet hole at the bottom of the buffer cavity, the bottom of the flow distribution cavity is closed and is symmetrically provided with two strip-shaped flow distribution joints on the left and right sides, the two crystallization rollers are symmetrically arranged on the left and right sides of the flow distribution cavity, at least two horizontal baffles are arranged in the flow distribution cavity and are spaced apart from each other, each horizontal baffle is divided into a left and right side-by-side flow guide area and a closed area, a plurality of flow guide holes are uniformly distributed on the flow guide area, the entire bottom of the closed area is sunken to form a slag collecting cavity, and the slag collecting cavity of the upper horizontal baffle is aligned with the flow guide area of the adjacent lower horizontal baffle.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of thin strip continuous casting, and particularly relates to an aluminum alloy double-roller thin strip continuous casting equipment and a flow distribution system. BACKGROUND

[0002] With the development of automobile lightening, light metals have become an indispensable automobile material for improving automobile fuel efficiency and reducing carbon dioxide emissions, and developing light alloys with good mechanical properties to replace traditional automobile steel parts has gradually become a trend. The aluminum alloy thin strip continuous casting technology is one of the near-net shape forming technologies, and its process principle is to directly cast the molten metal between a pair of counter-rotating and internally water-cooled crystallization rollers, and the molten pool liquid level exists in a closed space composed of two side sealing plates and roller surfaces. The molten metal solidifies to form a thin strip between the two rollers. Compared with the traditional continuous casting process, the double-roller thin strip casting has the advantages of short process, low production cost, energy saving, etc.

[0003] Currently, there are two kinds of aluminum alloy double-roller thin strip continuous casting. One is horizontal double-roller thin strip continuous casting (HTRC), in which the two crystallization rollers are arranged vertically, and the molten aluminum liquid passes through the counter-rotating crystallization rollers horizontally under the action of static pressure to obtain an aluminum strip. The advantages are low equipment cost and easy process control, but the disadvantages are low crystallization roller cooling intensity, low pulling speed and low production efficiency. The other is vertical double-roller thin strip continuous casting (VTRC), in which the two crystallization rollers are arranged horizontally, and the molten aluminum liquid passes through the counter-rotating crystallization rollers vertically under the action of static pressure to obtain an aluminum strip. The advantages are high production rate and good plate quality, and the cooling effect is stronger, but the faster pulling speed and cooling speed lead to more difficult process control.

[0004] In order to stably and uniformly distribute the molten metal into the narrow double-roller molten pool, a flow distributor is usually arranged above the double-roller molten pool, and the flow distribution is achieved by using flow distribution holes. However, the existing flow distributor still has problems such as uneven flow distribution, which causes turbulent flow of the molten metal, affects the normal operation of casting and rolling and the quality of the thin strip blank, and the internal structure of the flow distributor is too complex, which easily causes flow system failure due to blockage or scouring during use.

[0005] In view of the above, it is necessary to improve the existing double-roller thin strip continuous casting flow distribution system. SUMMARY

[0006] The main purpose of the present application is to provide an aluminum alloy double-roller thin strip continuous casting equipment and a flow distribution system, which can continuously and stably and uniformly distribute the aluminum liquid into the molten pool for a long time, thereby improving the casting and rolling quality of the thin strip.

[0007] To this end, the application provides an aluminum alloy double-roller thin strip continuous casting flow distribution system, which comprises a buffer cavity and a flow distribution cavity, the lower end of the flow distribution cavity is immersed in a stable molten pool formed between two crystallization rollers, the upper end of the flow distribution cavity is in communication with a liquid outlet hole at the bottom of the buffer cavity, the bottom of the flow distribution cavity is closed and two strip-shaped flow distribution slots are symmetrically arranged on the left and right sides of the flow distribution cavity, the two crystallization rollers are symmetrically arranged on the left and right sides of the flow distribution cavity, at least two horizontal baffles are arranged in the flow distribution cavity, each horizontal baffle is divided into a left and right side-by-side flow guide area and a closed area, the flow guide area is uniformly provided with a plurality of flow guide through holes, the entire bottom of the closed area is sunken to form a slag collecting cavity, and the slag collecting cavity of the upper horizontal baffle is aligned with the flow guide area of the adjacent lower horizontal baffle.

[0008] Specifically, the horizontal baffles are arranged in the middle enlarged section of the flow distribution cavity.

[0009] Specifically, the buffer cavity is further provided with a clamping hole at an upper position of the buffer cavity for facilitating clamping.

[0010] Specifically, the flow distributor is supported and installed above the stable molten pool by a support.

[0011] Specifically, the buffer cavity is a reverse trapezoidal cavity, and the flow distribution cavity is a variable cross-section rectangular cavity.

[0012] Specifically, the bottom of the buffer cavity is provided with a flow disturbing dam.

[0013] Specifically, the flow distributor is supported and installed above the stable molten pool by a support.

[0014] An aluminum alloy double-roller thin strip continuous casting device adopts the double-roller thin strip continuous casting flow distribution system.

[0015] Compared with the prior art, the present application has the following beneficial effects: by adding the buffer cavity above the flow distribution cavity, the metal liquid can be uniformly mixed and most of the kinetic energy can be consumed before the flow distribution cavity, the speed of the metal liquid entering the crystallization roller pool is slowed down, by halving the transverse baffle in the flow distribution cavity into the left and right side-by-side flow guide area and closed area, and by staggered arrangement of the flow guide area and the closed area of the upper and lower adjacent transverse baffles, the kinetic energy can be further consumed when the metal liquid passes through the flow guide hole on the flow guide area, and then the metal liquid touches the closed area of the lower transverse baffle and changes the direction of movement, moves transversely between the two adjacent transverse baffles, and this process can also consume part of the kinetic energy, in this way, through multi-stage kinetic energy consumption, the metal liquid can enter the pool uniformly and stably, so as to realize uniform flow distribution and improve the casting quality. In addition, when the metal liquid moves transversely to the position corresponding to the closed area, the inclusions brought by the raw materials in the smelting process float on the closed area and gather in the slag collecting cavity, so that the purpose of slag removal and metal purification can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 is a structure schematic diagram of an aluminum alloy twin-roll thin strip continuous casting flow distribution system provided by the embodiment of the present application;

[0018] Figure 2 is a side view of the buffer cavity and the flow distribution cavity involved in the embodiment of the present application

[0019] Figure 3 is a top view of the buffer cavity involved in the embodiment of the present application;

[0020] 1, buffer cavity; 2, flow distribution cavity; 3, crystallization roller; 4, stable pool; 5, liquid outlet hole; 6, strip flow distribution gap; 7, transverse baffle; 701, flow guide area; 702, closed area; 8, flow guide through hole; 9, slag collecting cavity; 10, expansion section; 11, clamping hole; 12, bracket; 13, rotating base; 14, induction furnace; 15, turnover mechanism; 16, dam. DETAILED DESCRIPTION

[0021] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0022] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0023] In addition, the terms "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first" and "second" can include one or more of the features explicitly or implicitly. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0024] Referring to Figures 1-3 An aluminum alloy double-roller thin strip continuous casting flow distribution system includes a buffer cavity 1 and a flow distribution cavity 2. The lower end of the flow distribution cavity 2 is immersed in a stable molten pool 4 formed between two crystallization rollers 3, and the upper end is in communication with a liquid outlet hole 5 at the bottom of the buffer cavity 1. The bottom of the flow distribution cavity 2 is closed and symmetrically provided with two strip-shaped flow distribution slots 6 on the left and right sides. The two crystallization rollers 3 are symmetrically arranged on the left and right sides of the flow distribution cavity 2. At least two horizontal baffles 7 are arranged in the flow distribution cavity 2. Each horizontal baffle 7 is divided into a left and right side-by-side flow guide area 701 and a closed area 702. The flow guide area 701 is uniformly provided with a plurality of flow guide through holes 8, and the entire bottom of the closed area 702 is sunken to form a slag collecting cavity 9. The slag collecting cavity 9 of the upper horizontal baffle 7 is aligned with the flow guide area 701 of the adjacent lower horizontal baffle 7.

[0025] When casting, the aluminum liquid from the upstream tundish forms a convection in the large-volume buffer cavity 1, so that the inclusions are fully floated and removed, while consuming most of the kinetic energy of the aluminum liquid, slowing down the speed of the aluminum liquid entering the crystallization roll 3 pool, and then part of the aluminum liquid flows into the lower flow distribution cavity 2 under the action of static pressure and convection, and then flows into the pool through the upper and lower two transverse baffles 7. The aluminum liquid flows uniformly and slowly through the two side strip flow distribution slots 6, reaches the pool flow balance in a short time, and forms a stable liquid column of a certain height in the flow distribution cavity 2.

[0026] In the embodiment, by adding a buffer cavity above the flow distribution cavity 2, the metal liquid can be uniformly mixed and most of the kinetic energy can be consumed before the flow distribution cavity 2, so that the speed of the metal liquid entering the crystallization roll 3 pool is slowed down. By halving the transverse baffles 7 in the flow distribution cavity 2 into left and right side-by-side flow guide areas 701 and closed areas 702, and by staggering the flow guide areas 701 and the closed areas 702 of the upper and lower adjacent transverse baffles 7, the kinetic energy of the metal liquid can be further consumed when the metal liquid passes through the flow guide holes in the flow guide areas 701. Then the metal liquid enters the closed area 702 of the lower transverse baffle 7, changes the direction of movement, and moves transversely between the adjacent two transverse baffles 7. This process can also consume part of the kinetic energy. In this way, through multi-stage kinetic energy consumption, the metal liquid can be uniformly and stably fed into the pool, so as to achieve uniform flow distribution and improve the casting quality.

[0027] In addition, the quality of the thin strip product is directly related to the state of the flow field in the pool, the distribution of the temperature field, and the purity of the aluminum liquid. If the slag on the surface of the pool enters the crystallizer with the metal liquid, it is easy to form accidents such as slag inclusion, strip breakage, and poor strip pattern. The slag on the surface of the pool may come from the inclusions brought by raw materials in the high-temperature aluminum liquid smelting process, the inclusions produced by the reaction of high-temperature aluminum liquid with air, and the inclusions produced by the reaction of high-temperature aluminum liquid with refractory materials. The production of slag is inevitable, therefore, how to prevent the slag from entering the crystallizer to cause production accidents puts strict requirements on the flow field, the slag suction design of the pool surface, etc.

[0028] In the embodiment, when the metal liquid moves transversely to the position corresponding to the closed area 702, the fine inclusions brought by raw materials in the smelting process can float on the closed area 702 and can be collected in the slag collection cavity 9, so as to achieve the purpose of slag removal and metal purification. The flow distribution cavity 2 is partially immersed in the stable pool 4 formed between the double rolls, which has a certain heat preservation effect on the flow distribution system, prevents the metal liquid in this area from prematurely solidifying and separating into thin strip products, and causes the product quality to decrease.

[0029] Referring to Figure 1It can be understood that in actual design, the flow distribution cavity 2 is divided into an enlarged section 10 in the middle and normal sections in the upper and lower parts, and the transverse baffle 7 is arranged in the middle enlarged section 10 of the flow distribution cavity 2. By arranging the transverse baffle 7 in the middle enlarged section 10, the flow rate of the molten metal can be further reduced, thereby facilitating the sufficient floating and collection of fine inclusions, and at the same time, the upper and lower parts are designed to be normal sizes, which can effectively avoid the problem of slow flow or even blockage caused by excessive turbulence suppression.

[0030] Referring to Figure 1 Specifically, a clamping hole 11 for facilitating clamping is arranged at the upper position of the buffer cavity 1, the flow distributor is supported and installed above the stable molten pool 4 by a support 12, the buffer cavity 1 is a reversed trapezoidal cavity, the two side walls and the bottom surface form a certain inclination angle, which increases the liquid space in the upper part of the flow distributor, and plays a buffering and refluxing role on the molten metal injected into the flow distributor, the flow distribution cavity 2 is a rectangular cavity, and the bottom of the buffer cavity 1 is provided with a flow disturbing dam 16.

[0031] In this embodiment, before casting starts, the two induction furnaces are simultaneously charged, one induction furnace is started to work first, and the other induction furnace is started to heat after a certain time. At the same time, the flow distribution system is placed on the support 12 through the specific clamping hole 11. When casting starts, the high-temperature molten aluminum liquid from the induction furnace is poured into the buffer cavity 1 at a constant speed at a certain angle. Due to the obstruction and reflection of the surrounding side walls, the bottom dam and the bottom surface, the aluminum liquid forms a convection in the large-volume trapezoidal buffer cavity 1, which is beneficial to the sufficient floating and removal of inclusions, and at the same time, the majority of kinetic energy of the aluminum liquid is consumed, and the speed of the aluminum liquid entering the molten pool of the crystallization roller 3 is slowed down. Then, part of the aluminum liquid flows into the rectangular cavity below under the action of static pressure and convection through the circular liquid outlet hole 5, and then the aluminum liquid uniformly and slowly flows into the molten pool through the two side strip flow distribution slots 6 after passing through the upper and lower transverse baffles 7, so that the flow balance of the molten pool is reached in a short time. The buffer cavity 1 and the flow distribution cavity 2 are integrally formed in the upper and lower parts and are made of refractory materials.

[0032] Referring to Figure 1 In some embodiments, the flow distribution system further comprises a rotating base 13 arranged at the side of the flow distributor, the rotating base 13 is provided with two induction furnaces 14 and a turnover mechanism 15 for driving the induction furnaces 14 to pour. As for the specific structure of the turnover mechanism 15, it is all prior art, which will not be described here.

[0033] In the embodiment, the whole rotating base 13 is placed above the crystallization roller 3 at a certain height, and the induction furnace 14 can realize longitudinal rotation pouring along the pouring center, thereby providing the metal liquid for the double-roller thin strip continuous casting and rolling production; the rotating base 13 can realize the rotation switching of the two induction furnaces 13 in the horizontal direction, the metal liquid in the induction furnace 14 can be poured into the distributor buffer cavity through the turnover mechanism 15, one can pour the metal liquid while the other can carry out the charging and smelting operation, thereby maximizing the time gap and improving the production efficiency.

[0034] The embodiment of the application integrates the distribution and the buffering, thereby saving the buffer or the transition device, shortening the process and improving the production efficiency; solving the problems of the metal melt flow disorder, the liquid surface fluctuation aggravation, the influence on the normal operation of the casting and rolling and the thin strip blank quality in the prior art; the internal structure of the distributor is too complex, and the distribution system is prone to failure due to the blockage or the flushing effect in the use process.

[0035] The application also provides a double-roller thin strip continuous casting equipment adopting the aluminum alloy double-roller thin strip continuous casting distribution system. Any technical solution disclosed by the application, if not otherwise stated, if a numerical range is disclosed, the disclosed numerical range is a preferred numerical range, and any person skilled in the art should understand that the preferred numerical range is only one of the many implementable numerical values with more obvious technical effects or representative values. Since there are too many values, it is impossible to enumerate them all, so the application discloses some values to illustrate the technical solutions of the application, and the above-mentioned values should not constitute a limitation on the protection scope of the application.

[0036] Meanwhile, if the above-mentioned application discloses or involves the mutually fixed connection of parts or structural members, the fixed connection can be understood as the detachable fixed connection (for example, the bolt or screw connection), or the non-detachable fixed connection (for example, the riveting or welding), and of course, the mutually fixed connection can be replaced by the integral structure (for example, the integral forming manufacturing by using the casting process) (obviously, the integral forming process cannot be used).

[0037] In addition, the terms used to represent the position relationship or the shape in any technical solution disclosed by the above-mentioned application include the approximate, similar or close states or shapes, unless otherwise stated. Any component provided by the application can be assembled from a plurality of individual components, or can be a single component manufactured by the integral forming process.

[0038] The above embodiments are merely exemplary of the application but are not intended to limit the scope of the application. It will be apparent to those having ordinary skill in the art that other changes and modifications to the described embodiments can be made without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments described herein but is to be accorded the full scope inherent in the claims, including both legal equivalents and conservative equivalents to each technical feature recited.

Claims

1. An aluminum alloy twin roll strip continuous casting flow distribution system characterized by: The application relates to an aluminum alloy double-roller thin strip continuous casting and flow distribution system, which comprises a buffer cavity (1) and a flow distribution cavity (2), the lower end of the flow distribution cavity (2) is immersed in a stable molten pool (4) formed between two crystallization rollers (3), the upper end of the flow distribution cavity (2) is communicated with a liquid outlet hole (5) at the bottom of the buffer cavity (1), the bottom of the flow distribution cavity (2) is closed and two strip-shaped flow distribution joints (6) are symmetrically arranged at the left and right sides of the flow distribution cavity (2), the two crystallization rollers (3) are symmetrically arranged at the left and right sides of the flow distribution cavity (2), at least two horizontal baffles (7) are arranged in the flow distribution cavity (2) and are spaced apart from each other, each horizontal baffle (7) is divided into a left and right parallel flow guide area (701) and a closed area (702), wherein, a plurality of flow guide through holes (8) are uniformly distributed on the flow guide area (701), the whole bottom of the closed area (702) is sunken to form a slag collecting cavity (9), the slag collecting cavity (9) of the horizontal baffle (7) located above is aligned with the flow guide area (701) of the horizontal baffle (7) located below.

2. The aluminum alloy twin roll strip continuous casting flow system of claim 1 wherein: The horizontal baffles (7) are arranged in a middle enlarged section (10) of the flow distribution cavity (2).

3. The aluminum alloy twin roll strip continuous casting flow system of claim 1 wherein: A clamping hole (11) for facilitating clamping is further arranged at an upper position of the buffer cavity (1).

4. The aluminum alloy twin roll strip continuous casting flow system of claim 1 wherein: The buffer cavity (1) is supported and installed above the stable molten pool (4) through a support (12).

5. The aluminum alloy twin roll strip continuous casting flow system of claim 1 wherein: The buffer cavity (1) is a reversed trapezoidal cavity, and the flow distribution cavity (2) is a rectangular cavity with a variable cross section.

6. The aluminum alloy twin roll strip continuous casting flow system of any of claims 1-5, wherein: A flow disturbing dam (16) is arranged at the bottom of the buffer cavity (1).

7. The aluminum alloy twin roll strip continuous casting flow system of claim 6, wherein: A rotary base (13) is further arranged at the side of the buffer cavity (1) and the support, the rotary base (13) is provided with two induction furnaces (14) and a turnover mechanism (15) for driving the induction furnaces (14) to pour.

8. An aluminum alloy twin roll strip continuous casting apparatus characterized by: The aluminum alloy double-roller thin strip continuous casting and flow distribution system is used.

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