Steel flow directional distribution rectifying ladle for thin-strip continuous casting and thin-strip continuous casting system

Abstract

The invention belongs to the technical field of thin-strip steel casting, and particularly relates to a steel flow directional distribution rectifying ladle for thin-strip continuous casting and a thin-strip continuous casting system. A steel flow directional distribution rectifying ladle for thin-strip continuous casting comprises a ladle body, and a rectifying field area, an arc-shaped guide slope and a stable flow outlet area are arranged in the ladle body. A vortex reduction buffer slope, an arc-shaped transition area and a buffer flow guide block are arranged in the rectification field area, and the buffer flow guide block is provided with an anti-impact buffer area, a fluid flow guide channel, a turbulent flow diffusion area and a flow expansion area which are communicated with one another; the stable flow outlet area is provided with a central water gap, a plurality of expansion area water gaps and a plurality of wall area water gaps; slits are formed in the central water gap; the expansion area water gaps and the wall area water gaps are symmetrically arranged on the left side and the right side of the central water gap at intervals; the arc-shaped guide slope is arranged on the rear side of the buffering flow guide block and guides molten steel into a slit of the water gap corresponding to the stable flow outlet area. Through the space gradient rectification design, the turbulence and vortex phenomena of the steel flow are effectively eliminated, the molten steel is uniformly and stably distributed, and the qualification rate and the production efficiency of thin strip products are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of thin strip steel casting, and particularly relates to a steel flow directional distribution rectifier package for thin strip continuous casting and a thin strip continuous casting system. BACKGROUND

[0002] The iron and steel industry is gradually moving towards a green, low-carbon, energy-saving, environmentally friendly and low-cost development path, and short process continuous casting and rolling technology is increasingly valued. As a continuous steel casting method close to the final shape, the twin-roll thin strip continuous casting technology can directly produce thin strip cast blanks with a thickness of not more than 10 mm and can be directly processed into strip-shaped materials. Compared with traditional continuous casting technology, thin strip continuous casting technology is particularly prominent with its short process flow, low energy consumption, less investment demand, small floor area, high labor productivity and low production cost.

[0003] In the thin strip continuous casting process, a transition package needs to be set in the middle of the double-roll molten pool, which not only slows down the gravitational potential energy generated when the molten steel falls, but also slows down the impact of the molten steel on the core nozzle and the lower molten pool, stabilizes the molten pool liquid level, and ensures the quality of the molten steel. With the increasing advantages of short process technology, the demand for increasing the throughput and the molten steel speed of thin strip continuous casting is increasing, and the traditional thin strip blank process system cannot meet the current production demand, especially the structure of the existing transition package. When a large flow of molten steel enters the transition package, a rapid vortex is generated in the fluid region, causing a large fluctuation in the liquid level of the transition package. This will cause the speed of the molten steel flowing out of the transition package to be uneven, seriously affecting the stability of the liquid level of the lower molten pool. Since the molten steel flows out through the 9-18 sizing nozzle areas of the transition package, as the throughput increases, the unstable flow field inside the transition package becomes more serious, not only causing a large difference in the outlet speed of the molten steel in the transition package, but also causing a large drop in the temperature of the molten steel at the two outlets. The temperature of the molten steel at the middle outlet is high, and the temperature of the molten steel at the side outlet is low, with a temperature difference of more than 20℃, which ultimately affects the surface quality of the steel plate.

[0004] In order to solve the above problems, the Chinese invention patent application file with publication number CN111347031A discloses a dam weir type transition package for thin strip continuous casting, which sets a combination of a weir and a dam inside the transition package. After the molten steel enters the transition package from the inlet, it passes through the weir bottom in turn, climbs over the dam top after the liquid level rises, enters the distributed liquid outlet hole of the transition package, and uniformly flows out of the transition package. Although this design can suppress the occurrence of an unstable flow field inside the transition package to some extent and reduce the temperature difference between the two outlet temperatures and the middle liquid control temperature to some extent, but due to the continuous irregular scouring of the molten steel on the dam body, the dam body material is prone to fall off, thereby destroying the original stable flow field. In addition, the fallen refractory material will flow to the sizing nozzle channel with the flow of the molten steel, and will block the sizing nozzle channel with the accumulation of time, thereby causing the molten steel to be blocked and affecting the surface quality of the thin strip product. SUMMARY

[0005] In view of this, the purpose of the present application is to provide a steel flow directional distribution and rectification package for thin strip continuous casting, to solve the technical problem that the existing transition package is difficult to ensure stable flow of liquid steel in the package body, thereby affecting the surface quality of thin strip products; the purpose of the present application is also to provide a thin strip continuous casting system to meet the existing high steel flow and large roll diameter process requirements.

[0006] To solve the above problems, the steel flow directional distribution and rectification package for thin strip continuous casting provided by the present application adopts the following technical scheme: The steel flow directional distribution and rectification package for thin strip continuous casting is used to receive liquid steel flowing from a submerged nozzle, comprising a package body, wherein a rectification field area, an arc-shaped guide slope and a stable flow outlet area are arranged in the package body; The rectification field area is provided with a vortex reduction buffer slope, an arc-shaped transition area and a buffer flow guide block mounted on the inner bottom wall of the package body, the buffer flow guide block has an impact-resistant buffer area, a fluid flow guide channel, a turbulent diffusion area and an expansion area which are interconnected, the impact-resistant buffer area is arranged opposite to the submerged nozzle, the turbulent diffusion area and the expansion area are respectively located on the front and rear sides of the impact-resistant buffer area, the turbulent diffusion area is close to the vortex reduction buffer slope, and the expansion area is close to the arc-shaped guide slope; the arc-shaped transition area is arranged at the position corresponding to the intersection of the two adjacent vertical inner side walls of the package body, and the vortex reduction buffer slope is arranged at the position corresponding to the intersection of the inner bottom wall and the vertical inner side wall of the package body; The stable flow outlet area is provided with a central nozzle having a slit, a plurality of expansion area nozzles and a plurality of wall area nozzles which are symmetrically arranged on the left and right sides of the central nozzle, and the wall area nozzles are located outside the expansion area nozzles; The arc-shaped guide slope is used to guide the liquid steel into the slit of the corresponding nozzle of the stable flow outlet area.

[0007] The beneficial effects of the steel flow directional distribution rectifier bag for thin strip continuous casting are as follows: the three-stage spatial gradient rectification structure is formed by arranging the rectification field area, the buffer arc slope and the stable flow outlet area, and the phased guidance, rectification and buffering of the steel flow from the inlet to the outlet are realized. The arc transition area is arranged at the corner of the bag body, so that the steel flow uses the curved surface to smoothly turn, and the boundary layer separation and low pressure vortex caused by the right angle mutation are suppressed; the vortex reduction buffer slope decomposes the vertical impact kinetic energy into tangential / normals components, uses the Coanda effect to keep the steel flow attached to the wall flow, eliminates the "dead water area" of the steel flow, significantly reduces the vortex intensity, and achieves the effects of reducing liquid surface fluctuation, dispersing scouring protection refractory and improving temperature uniformity; the impact-resistant buffer area, the fluid guide channel, the turbulent diffusion area and the flow expansion area and other functional areas are arranged on the buffer guide block, and through multiple guidance, buffering and diffusion in space, the kinetic energy and non-uniformity of the steel flow are systematically resolved, so that the flow field is stable and the steel liquid is uniformly distributed; the arc guide slope guides the steel flow to smoothly enter the stable flow outlet area, and the stable flow outlet area is provided with multiple groups of water outlets with slits matched with different positions of the steel flow, so that fine distribution of flow is realized, and the steel flow can realize zoned outflow, uniform flow speed and consistent temperature distribution under the conditions of large flow and high speed, effectively reducing the temperature difference between the wall area steel flow and the middle steel flow, and improving the finished product quality of the thin strip steel plate.

[0008] Further, the liquid guide channels are arranged at least two in the front and back directions, and the intersection positions of the extension lines of the liquid guide channels and the corresponding side walls of the bag body are located on the front side of the arc guide slope.

[0009] Beneficial effects: multiple liquid guide channels can quickly disperse the steel flow and avoid local turbulence caused by a single liquid guide channel; in addition, the liquid guide channels can ensure that the steel flow has completed rectification before entering the arc guide slope, so that the arc guide slope can more efficiently guide the steel flow to the stable flow outlet area, avoiding flow field disorder.

[0010] Further, each liquid guide channel is inclined and has a converging structure.

[0011] Beneficial effects: the converging structure can accelerate and stably guide the steel flow, ensure the consistency of the steel flow direction, and ensure the uniformity of the kinetic energy of the steel flow entering the stable flow outlet area.

[0012] Further, the buffer flow guide block comprises a base, a turbulent flow buffer block body, a first flow guide block body and a second flow guide block body which are formed on the base and arranged in front and back intervals, and the turbulent flow buffer block body, the first flow guide block body and the second flow guide block body are symmetrically arranged left and right with two; the impact-resistant buffer area is a circular recess provided on the base, and the gap space between the turbulent flow buffer block body and the first flow guide block body and the gap space between the first flow guide block body and the second flow guide block body form the liquid flow guide channel respectively; the front side of the two turbulent flow buffer block bodies is provided with an arc flow guide surface, and the area between the two arc flow guide surfaces forms the turbulent flow diffusion area; the rear side of the two second flow guide block bodies is provided with an expansion flow surface arranged obliquely, and the area between the two expansion flow surfaces forms an expansion flow area in the shape of an expansion.

[0013] Beneficial effects: The functions of each area on the buffer flow guide block are clear, and the impact-resistant buffer area directly bears the impact of the steel flow; the liquid flow guide channel formed by the turbulent flow buffer block body and the first flow guide block body and the liquid flow guide channel formed by the first flow guide block body and the second flow guide block body guide the molten steel in the set direction; the turbulent flow diffusion area and the expansion flow area gradually eliminate the kinetic energy of the molten steel, realize the progressive regulation and control of impact buffering, directional flow guiding and uniform diffusion, and the stability of the flow field is significantly improved.

[0014] Further, the front side of the first flow guide block body is a first front flow guide slope, the rear side is a first rear flow guide slope, and the first front flow guide slope and the first rear flow guide slope are connected by a circular arc surface; the front side of the second flow guide block body is a second front flow guide slope, and the second front flow guide slope and the expansion flow surface are connected by a circular arc.

[0015] Beneficial effects: The circular arc transition avoids vortex generation caused by sharp corners, reduces energy loss and turbulence of the steel flow at the edges of the first flow guide block body and the second flow guide block body, makes the flow field smoother, and also protects the refractory from local erosion.

[0016] Further, the package body comprises a package bottom, a front side wall and a rear side wall which are fixed on the front and rear sides of the package bottom and arranged in parallel intervals, a left side wall and a right side wall which are fixed on the left and right sides of the package bottom and arranged in parallel intervals, and two inclined side walls which are fixed on the package bottom and correspondingly connect the front side wall and the left side wall and the front side wall and the right side wall, and the inner side wall of the inclined side wall and the inner side wall of the left side wall or the right side wall form the arc-shaped transition area arranged vertically, and the inner wall surface of the package bottom is the inner bottom wall, and the intersection of the inner side wall of the front side wall and the inner bottom wall forms the vortex reduction buffer slope; a stable flow area cover plate is arranged on the rear side of the arc-shaped guide slope on the package bottom, and the central nozzle, the expansion area nozzle and the wall area nozzle are all provided on the stable flow area cover plate.

[0017] Further, the stable flow area cover plate is provided with a clamping groove corresponding to the position of the central water gap, the expansion area water gap and the wall area water gap, and the clamping groove has a trapezoidal clamping hole; the slit is inserted into the corresponding clamping groove from top to bottom, and the slit has a trapezoidal clamping section matched with the trapezoidal clamping hole, and the outlet of the slit is located below the stable flow area cover plate.

[0018] Beneficial effect: The slit is convenient to install at each water gap, and the stability of the slit after installation is ensured, and displacement under the impact of the steel flow is avoided.

[0019] Further, the package body is a symmetrical structure, the geometric center of the central water gap coincides with the geometric center of the stable flow area cover plate, and the straight line connecting the geometric center of the impact-resistant buffer area is located on the symmetrical plane of the package body.

[0020] Beneficial effect: The symmetrical structure of the package body can ensure the consistency of the steel flow in the left and right directions; when the straight line connecting the geometric center of the central water gap and the geometric center of the impact-resistant buffer area is located on the symmetrical plane of the package body, the path of the steel flow from the inlet to the outlet is symmetrical, and the uniformity of the flow field is further improved.

[0021] Further, the inner bottom wall of the package body is inclined downward from front to back towards the stable flow outlet area.

[0022] Beneficial effect: The inclined inner bottom wall is beneficial to guide the steel liquid to flow to the stable flow outlet area, and avoid the residue and accumulation of the steel liquid on the inner bottom wall.

[0023] The technical scheme of the thin strip continuous casting system provided by the present application is: The thin strip continuous casting system adopts the steel flow directional distribution and rectification package in any one of the above technical schemes, and details are not repeated here.

[0024] The beneficial effect of the thin strip continuous casting system is that the thin strip continuous casting system has the flow field stability advantage of the steel flow directional distribution and rectification package for thin strip continuous casting, can meet the process requirements under the condition of high flow and large roll diameter, improve the overall production efficiency, reduce energy consumption, and significantly improve the surface quality and dimensional accuracy of the produced thin strip steel. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a perspective view of the steel flow directional distribution and rectification package for thin strip continuous casting of the present application; Figure 2 It is a front view of Figure 1 Figure 3 It is a structure diagram of the buffer guide block in Figure 1 Figure 4 It is a structure diagram of the stable flow outlet area in the steel flow directional distribution and rectification package for thin strip continuous casting of the present application; ​​Figure 5 A cross-sectional view of the steel flow directional distribution rectifier package in a central position of the thin strip continuous casting system of the present application; Figure 6 A structure view of the slit; Figure 7 A structure view of the thin strip continuous casting system of the present application.

[0026] Explanation of reference numerals: 1, package body; 11, front side wall; 12, rear side wall; 13, bevel wall; 14, left side wall; 15, right side wall; 2, rectifier field area; 21, arc-shaped transition area; 22, vortex reduction buffer slope; 3, arc-shaped guide slope; 4, stable flow outlet area; 41, stable flow area cover plate; 42, central nozzle; 43, expansion area nozzle; 44, wall area nozzle; 45, slit; 451, trapezoidal clamping section; 46, trapezoidal clamping opening; 5, buffer flow guide block; 51, turbulent flow buffer block; 511, inclined flow guide surface; 512, arc-shaped flow guide surface; 52, first flow guide block; 521, first front flow guide slope; 522, first rear flow guide slope; 53, second flow guide block; 531, second front flow guide slope; 532, flow expansion surface; 54, circular recess; 55, turbulent flow diffusion area; 56, first liquid flow guide channel; 57, second liquid flow guide channel; 58, flow expansion area; 101, long nozzle; 102, tundish; 103, submerged nozzle; 104, directional distribution rectifier package; 105, flow distributor; 106, molten pool; 107, pair of rollers. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

[0028] The embodiments of the steel flow directional distribution rectifier package for thin strip continuous casting provided by the present application are as follows: As shown in Figure 1 , Figure 2 and Figure 7 , the steel flow directional distribution rectifier package for thin strip continuous casting is used for receiving molten steel flowing in from a submerged nozzle, and includes a package body 1. The top of the package body 1 is provided with a top cover (not shown in the figure), and the top cover is provided with a insertion hole for the submerged nozzle 103 to insert into. The package body 1 is provided with a rectifier field area 2, an arc-shaped guide slope 3 and a stable flow outlet area 4.

[0029] Since the steel flow finally flows to the stable flow outlet area 4, for the convenience of description, the stable flow outlet area 4 is defined as being located at the rear side of the package body 1.

[0030] In this embodiment, as shown in Figure 1 andFigure 2 As shown in the drawings, the package body 1 is of symmetrical structure, and the package body 1 comprises a package bottom, a front side wall 11, a rear side wall 12, a left side wall 14, a right side wall 15 and two inclined side walls 13. The front side wall 11 and the rear side wall 12 are respectively fixed on the front and rear sides of the package bottom and are arranged in parallel and at intervals. The left side wall 14 and the right side wall 15 are respectively fixed on the left and right sides of the package bottom and are arranged in parallel and at intervals. The two inclined side walls 13 are fixed on the package bottom and are arranged symmetrically on the left and right sides of the front side wall 11. One of the two inclined side walls 13 connects the front side wall 11 and the left side wall 14, and the inner side wall of the inclined side wall 13 and the inner side wall of the left side wall 14 meet to form an arc-shaped transition area 21 arranged vertically. The other inclined side wall 13 connects the front side wall 11 and the right side wall 15, and the inner side wall of the inclined side wall 13 and the inner side wall of the right side wall 15 also meet to form an arc-shaped transition area 21 arranged vertically. The radius of the arc-shaped transition area 21 ranges from 250 mm to 300 mm.

[0031] The inner surface of the package bottom is the inner bottom wall of the package body 1. The inner side wall of the front side wall 11 and the inner bottom wall meet to form a vortex reduction buffer slope 22, which is a transition arc with a radius ranging from 200 mm to 400 mm. The arc-shaped transition area 21 and the vortex reduction buffer slope 22 are both located in the range of the rectification field area 2. Figure 5 As shown in the drawings, the inner bottom wall is arranged to be inclined downward toward the stable flow outlet area 4 from front to back, and the inclination angle is 3°. The angle can be reasonably adjusted according to actual needs. When pouring is stopped, the molten steel can flow along the inclined inner bottom wall to the stable flow outlet area 4, and there is no excessive molten steel remaining on the inner bottom wall, thereby avoiding subsequent solidification of the molten steel.

[0032] As shown in the drawings, Figure 2 , Figure 3 and Figure 5As shown, the rectifying field area 2 is also provided with a buffer flow guide block 5, which is made of sintered high zirconium brick and has high thermal stability and corrosion resistance, is embedded in the package bottom and is fixed and sealed with the package bottom by means of cement. The buffer flow guide block 5 is of a symmetrical structure formed integrally and is arranged at the rear side of the vortex reduction buffer slope 22, with a distance range of 100mm-400mm from the vortex reduction buffer slope 22. After the buffer flow guide block 5 is installed, the symmetrical plane thereof coincides with the symmetrical plane of the package body 1. In this embodiment, the buffer flow guide block 5 includes a base and a turbulent flow buffer block body 51, a first flow guide block body 52 and a second flow guide block body 53 which are arranged in front of and behind the base and are symmetrical left and right. The base is provided with a circular recess 54 which is arranged opposite to the submerged nozzle in the up-down direction, but has a certain distance therefrom, and the geometric center of the circular recess 54 is located on the above-mentioned symmetrical plane. In actual production, the outer diameter of the circular recess 54 matches the caliber of the submerged nozzle and is within 30mm-50mm, and the depth of the circular recess 54 ranges from 20mm to 50mm. The circular recess 54 forms an impact-resistant buffer zone to resist the vertical impact of the steel flow.

[0033] The front side of the turbulent flow buffer block body 51 is provided with an arc-shaped flow guide surface 512, and the rear side is provided with an inclined flow guide surface 511, and the area surrounded by the two arc-shaped flow guide surfaces 512 forms a turbulent flow diffusion zone 55. The radius of the circular arc of the arc-shaped flow guide surface 512 ranges from 10mm to 50mm, and the angle between the inclined flow guide surface 511 and the horizontal plane ranges from 30° to 40°. The front side of the first flow guide block body 52 is a first front flow inclined surface 521, and the rear side is a first rear flow inclined surface 522, and the first front flow inclined surface 521 and the first rear flow inclined surface 522 are connected by a circular arc surface, and the area between the first front flow inclined surface 521 and the inclined flow guide surface 511 forms a first liquid flow guide channel 56. The angle between the first front flow inclined surface 521 and the horizontal plane ranges from 70° to 100°, and the angle between the first rear flow inclined surface 522 and the horizontal plane is 45°.

[0034] The front side of the second flow guide block body 53 is a second front flow inclined surface 531, and the rear side is an inclined expansion surface 532, and the second front flow inclined surface 531 and the expansion surface 532 are connected by a circular arc. The area between the second front flow inclined surface 531 and the first rear flow inclined surface 522 forms a second liquid flow guide channel 57, and the area between the two expansion surfaces 532 forms an expansion zone 58 in the shape of an expanded mouth. The angle between the second front flow inclined surface 531 and the horizontal plane ranges from 110° to 130°, and the angle between the extension planes of the two expansion surfaces 532 ranges from 60° to 85°.

[0035] As can be seen from the above, the turbulent diffusion zone 55 and the diffusion zone 58 are respectively located on the front and rear sides of the impact-resistant buffer zone, and are in communication with the first liquid guide channel 56 and the second liquid guide channel 57. The turbulent diffusion zone 55 is close to the vortex reduction buffer slope 22, and the diffusion zone 58 is close to the arc-shaped guide slope 3. The first liquid guide channel 56 and the second liquid guide channel 57 are both in a closed structure, and their directions can be adjusted by adjusting the inclination angles of the inclined guide surface 511, the first front guide inclined surface 521, the first rear guide inclined surface 522, and the second front guide inclined surface 531, but the intersection points of the extension lines of the liquid guide channels with the corresponding side walls of the package 1 are all located on the front side of the arc-shaped guide slope 3.

[0036] The arc-shaped guide slope 3 is located on the rear side of the buffer guide block 5, and the spacing range between the arc-shaped guide slope 3 and the buffer guide block 5 is 300mm-500mm. The arc-shaped guide slope 3 is a circular arc slope with an outward convex surface, and the arc length radius range is 300mm-600mm. The flow field area between the buffer guide block 5 and the arc-shaped guide slope 3 is a transition flow area, and the flow field area on the rear side of the arc-shaped guide slope 3 is a stable flow outlet area 4.

[0037] As shown in Figure 4 The stable flow area cover plate 41 is located on the rear side of the arc-shaped guide slope 3 in the stable flow outlet area 4, and the central water gap 42, the expansion area water gap 43, and the wall area water gap 44 are arranged on the stable flow area cover plate 41. The length of the stable flow area cover plate 41 ranges from 1500mm to 2900mm, and the width ranges from 120mm to 400mm. The geometric center of the central water gap 42 coincides with the geometric center of the stable flow area cover plate 41. The expansion area water gap 43 is arranged symmetrically about the central water gap 42, and the wall area water gap 44 is also arranged symmetrically about the central water gap 42, but the wall area water gap 44 is located on the outer side of the expansion area water gap 43. The number of the expansion area water gap 43 and the wall area water gap 44 can be reasonably designed according to actual needs. The length of the central water gap 42 ranges from 300mm to 580mm, and the width ranges from 50mm to 60mm; the length of the expansion area water gap 43 ranges from 200mm to 480mm, and the width ranges from 50mm to 60mm; the length of the wall area water gap 44 ranges from 300mm to 580mm, and the width ranges from 50mm to 60mm. In this embodiment, the length of the central water gap 42 is the same as the length of the wall area water gap 44, and both are greater than the length of the expansion area water gap 43. The widths of the central water gap 42, the wall area water gap 44, and the expansion area water gap 43 are the same.

[0038] The distance between the central water inlet 42 and the adjacent extension zone water inlet 43 is 20mm to 50mm; the distance between two adjacent extension zone water inlets 43 located on the same side as the central water inlet 42 is 30mm to 90mm; the distance between the adjacent extension zone water inlet 43 located on the same side as the central water inlet 42 and the wall zone water inlet 44 is 20mm to 50mm; the distance between two adjacent wall zone water inlets 44 located on the same side as the central water inlet 42 is 30mm to 90mm.

[0039] like Figure 4 As shown, slits 45 are installed at the central inlet 42, each expansion zone inlet 43, and each wall zone inlet 44 to form corresponding slit inlets. The length of the slits 45 ranges from 150mm to 500mm, and the width ranges from 5mm to 15mm. Figure 5 As shown, the cover plate 41 in the stable flow region is provided with slots corresponding to the positions of the central inlet 42, the expansion zone inlet 43, and the wall zone inlet 44. These slots have trapezoidal openings 46. For example... Figure 6 As shown, the slit 45 has a trapezoidal locking segment 451 that matches the trapezoidal bayonet 46. During installation, the slit 45 is inserted into the corresponding slot from top to bottom, so that the trapezoidal locking segment 451 is locked in place at the trapezoidal bayonet 46. At this time, the outlet of the slit 45 is located below the cover plate 41 in the stable flow region. In actual production, the outlet end of each slit 45 is inserted into the lower flow field, extending below the liquid surface.

[0040] The specific working principle of the steel flow directional distribution rectifier for thin strip continuous casting of the present invention is as follows: In actual production, such as Figure 7 As shown, molten steel in the ladle flows into the tundish 102 through the long nozzle 101, and then into the directional distribution rectifier ladle of the present invention through the submersible nozzle 103 at the bottom of the tundish 102. The bottom of the submersible nozzle 103 is inserted into the ladle body 1, at a distance of 100mm to 200mm from the inner bottom wall of the ladle body 1. The steel flow density is 7000 to 7500 kg / m³. 3 The molten steel in the rectifier flows through the slit nozzles to the distributor 105. The distributor 105 is inserted into the molten pool 106, and the molten steel in the molten pool 106 flows between the rollers 107 to form thin strip steel.

[0041] When the molten steel passes through the submerged nozzle into the enclosure 1, due to the action of gravitational potential energy, not only a large external force impact on the enclosure 1 area, but also a large disturbance to the flow field area, which will cause more vortex and liquid surface fluctuation near the steel flow inlet area, this fluctuation will be in the form of wave transmission to the entire flow field area, thereby affecting the entire flow field liquid surface stability. The thin strip continuous casting steel flow directional distribution rectifier package of the present application is internally provided with three functional areas of rectifier field area 2, arc-shaped guide slope 3 and stable flow outlet area 4, which will guide, rectify and buffer the steel flow from the inlet to the outlet in stages, effectively reducing the vortex and liquid surface fluctuation.

[0042] Wherein, the impact-resistant buffer area on the buffer guide block is arranged at a position vertically opposite to the submerged nozzle, locally buffers the position where the steel flow high-speed impact easily produces violent disturbance, effectively controls the turbulent diffusion of the core area; the kinetic energy and non-uniformity of the steel flow are systematically eliminated through the multiple guiding, buffering and diffusion in space of the buffer guide block, the flow field is stabilized, and the liquid distribution is uniform. The arc-shaped transition area 21 increases the flow distance of the steel flow, makes the steel flow smoothly turn along the curved surface, avoids the boundary layer separation and low pressure vortex caused by the right angle mutation. The vortex reduction buffer slope 22 decomposes the vertical impact kinetic energy into tangential / normals components, uses the Coanda effect to keep the steel flow adhering to the wall flow, eliminates the "dead water area" of the steel flow, significantly reduces the vortex intensity by 60%-80%, and also reduces the liquid surface fluctuation, disperses the scouring protection refractory, and improves the temperature uniformity, creating stable inflow conditions for the subsequent.

[0043] In addition, the flow rate of the nozzle with multiple groups of installed slits 45 in the stable flow outlet area 4 is matched with the flow field area, so that the steel flow can realize zoned outflow, uniform flow rate and consistent temperature distribution under the conditions of large flow rate and high speed, effectively reducing the temperature difference between the two ends and the middle, and improving the quality of thin strip steel plate products. The outlets of each group of nozzles are directly immersed in the lower flow field, avoiding the splashing of the outflowing steel flow in the flow process in the rectifier, and reducing the fluctuation of the lower flow field.

[0044] The thin strip continuous casting steel flow directional distribution rectifier package of the present application forms a layer-by-layer progressive liquid buffering and uniform distribution path in the enclosure 1 by using the arc-shaped transition area 21, the vortex reduction buffer slope 22, the buffer guide block 5, the arc-shaped guide slope 3 and the multiple group of narrow slit nozzles, systematically solves the problems of serious vortex, unstable liquid surface and uneven temperature distribution of the thin strip continuous casting transition package under the conditions of high flow rate and large roll diameter, significantly improves the flow stability and outlet temperature uniformity of the steel flow, and meets the development needs of green, low-carbon and efficient short process continuous casting technology.

[0045] The present application is used together with a traditional transition package to perform water model experiment flow test, and mainly investigates the maximum lifting height of the liquid surface distance from the bottom of the water inlet area, the average change height of the liquid surface in the flow field area, and the maximum lifting height of the liquid surface area at the steel liquid outlet. Through test verification, the maximum lifting height of the liquid surface distance from the bottom of the water inlet area, the average change height of the liquid surface in the flow field area, and the maximum lifting height of the liquid surface area at the steel liquid outlet of the thin strip continuous casting steel flow directional distribution and rectification package of the present application are obviously lower than those of the traditional transition package, so that the steel flow turbulence and vortex phenomenon can be effectively eliminated, and uniform and stable distribution of the steel liquid is realized.

[0046] In other embodiments, the buffer flow guide block can be reasonably designed according to the size of the package body, and the liquid flow guide channel is not limited to two in the present application, but can be only one liquid flow guide channel, or more than three liquid flow guide channels.

[0047] Embodiments of the thin strip continuous casting system of the present application: As shown in Figure 7 The thin strip continuous casting system includes a tundish 102, a directional distribution and rectification package 104, a flow distributor 105, a molten pool 106, and a pair of rollers 107. The tundish 102 is connected with a ladle through a long nozzle 101. The submerged nozzle 103 at the bottom of the tundish 102 is inserted into the directional distribution and rectification package 104. Each slit nozzle of the directional distribution and rectification package 104 is inserted into the flow distributor 105. The flow distributor 105 is inserted into the molten pool 106. The steel liquid in the molten pool 106 flows between the pair of rollers 107 to form a thin strip steel. The structure of the directional distribution and rectification package 104 is the same as that in the above-described embodiments of the thin strip continuous casting steel flow directional distribution and rectification package, and will not be described in detail here.

[0048] According to the above description of the present specification, those skilled in the art can also understand that the terms used such as "upper", "lower", "front", "rear", "left", "right", "horizontal", "bottom", "inner", "outer" and the like indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings of the present specification, which are only for the purpose of facilitating the description of the present application and simplifying the description, and do not explicitly or implicitly indicate or suggest that the devices or elements involved must have the specific orientation, be constructed and operated in a specific orientation, therefore the above orientation or positional relationship terms cannot be understood or interpreted as a limitation on the present application.

[0049] In the description of the present specification, the meaning of "a plurality of" is at least two, such as two, three or more, etc., unless otherwise explicitly and specifically limited.

[0050] The above is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A ladle for directional distribution and rectification of molten steel flow in thin strip continuous casting, used to receive molten steel flowing in from an immersion nozzle, comprising a ladle body, characterized in that, The package contains a flow rectification area, an arc-shaped guide slope, and a stable flow outlet area; The rectifying field area is equipped with a vortex reduction buffer slope, an arc-shaped transition zone, and a buffer guide block installed on the bottom wall of the package. The buffer guide block has interconnected anti-impact buffer zones, fluid guiding channels, turbulent diffusion zones, and flow expansion zones. The anti-impact buffer zone is arranged vertically opposite to the submersible nozzle. The turbulent diffusion zone and the flow expansion zone are located on the front and rear sides of the anti-impact buffer zone, respectively. The turbulent diffusion zone is close to the vortex reduction buffer slope, and the flow expansion zone is close to the arc-shaped guide slope. The arc-shaped transition zone is located at the intersection of two corresponding adjacent vertical inner walls of the package. The vortex reduction buffer slope is located at the intersection of the inner bottom wall and the corresponding vertical inner wall of the package. The stable outflow area is equipped with a central water inlet, each with a slit inside, and multiple extension zone water inlets and multiple wall zone water inlets symmetrically arranged on the left and right sides of the central water inlet. The wall zone water inlets are located outside the extension zone water inlets. The curved guide slope is used to guide molten steel into the narrow slit of the corresponding nozzle in the stable flow outlet area.

2. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 1, characterized in that, The liquid guiding channels are provided at least two at intervals in the front-to-back direction, and the intersection of the extension line of each liquid guiding channel and the corresponding side wall of the package is located on the front side of the arc-shaped guide slope.

3. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 2, characterized in that, All liquid flow channels are arranged at an angle and have a tapered opening.

4. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 2 or 3, characterized in that, The buffer guide block includes a base and turbulent buffer blocks, a first guide block, and a second guide block formed on the base and arranged at intervals. Two turbulent buffer blocks, a first guide block, and a second guide block are symmetrically arranged on the left and right. The impact-resistant buffer is a circular concave platform set on the base. The gap space between the turbulent buffer block and the first guide block, and the gap space between the first guide block and the second guide block respectively form the liquid guiding channel. The front side of each of the two turbulent buffer blocks is provided with an arc-shaped guide surface, and the area between the two arc-shaped guide surfaces forms the turbulent diffusion zone. The rear side of each of the two second guide blocks is provided with an inclined flow-expanding surface, and the area between the two flow-expanding surfaces forms a flared flow-expanding zone.

5. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 4, characterized in that, The front side of the first guide block is a first front guide slope, and the rear side is a first rear guide slope. The first front guide slope and the first rear guide slope are connected by a circular arc surface. The front side of the second guide block is a second front guide slope, and the second front guide slope is connected to the flow expansion surface by a circular arc surface.

6. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 5, characterized in that, The package includes a bottom, a front wall and a rear wall fixed to the front and rear sides of the bottom and arranged in parallel and spaced apart, a left wall and a right wall fixed to the left and right sides of the bottom and arranged in parallel and spaced apart, and two oblique walls fixed to the bottom and correspondingly connecting the front wall and the left wall, and the front wall and the right wall. The intersection of the inner wall of the oblique wall and the inner wall of the left wall or the right wall forms a vertically arranged arc-shaped transition zone. The inner surface of the bottom is the inner bottom wall. The intersection of the inner wall of the front wall and the inner bottom wall forms the vortex reduction buffer slope. A stabilizing flow area cover plate is provided on the bottom of the package behind the arc-shaped guide slope. The central water inlet, the expansion zone water inlet and the wall zone water inlet are all opened on the stabilizing flow area cover plate.

7. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 6, characterized in that, The cover plate of the stable flow area is provided with slots at the positions corresponding to the central water inlet, the expansion zone water inlet and the wall zone water inlet. The slots have trapezoidal openings. The slit is inserted into the corresponding slot from top to bottom. The slit has a trapezoidal segment that matches the trapezoidal opening. The outlet of the slit is located below the cover plate of the stable flow area.

8. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 6 or 7, characterized in that, The package has a symmetrical structure, the geometric center of the central inlet coincides with the geometric center of the stable flow zone cover, and the straight line connecting the geometric center of the shock-resistant buffer zone is located on the symmetrical plane of the package.

9. The steel flow directional distribution rectifier for thin strip continuous casting according to claim 1, characterized in that, The inner bottom wall of the package is inclined downwards from front to back toward the stable outlet area.

10. A thin strip continuous casting system, characterized in that, Includes the steel flow directional distribution rectifier for thin strip continuous casting as described in any one of claims 1-9.

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