Continuous casting method

Abstract

The invention relates to a method for continuous casting of metal, in particular steel, wherein liquid metal is conducted from a movably mounted ladle into a continuous casting tundish by means of a shroud and is conducted from the continuous casting tundish into a casting mould via an outlet, the tundish compensating for the interruptions when the ladles are exchanged and the ladles being mounted in a movement device, characterized in that, at the start of casting, i.e. when the liquid metal is first being poured into the tundish, the ladle is positioned such that the shroud is in the region of a transverse centre of the tundish and, after a desired surface level of the bath has been reached, the ladle or the tundish or the ladle and the tundish are moved, and in particular laterally shifted, such that, to form a single rolling kind of flow of the metal in the tundish, the shroud is offset outside of the transverse centre of the tundish in relation to a side wall, and the invention also relates to a continuous casting plant and to a fitting for the tundish.

Description

[0001] CONTINUOUS CASTING PROCESS

[0002] The invention relates to a continuous casting plant, a distributor for continuous casting plants and a method for continuous casting.

[0003] Continuous steel casting is a well-known process for the continuous casting of steel slabs.

[0004] For this purpose, steel is usually produced in a converter, transferred from the steel converter to a ladle and from the ladle via a distributor to the casting mold.

[0005] The distributor's task is to ensure an uninterrupted flow of steel after one ladle has been emptied and the next ladle has been fed.

[0006] In principle, it must be ensured that there are no inclusions in the liquid steel, in particular no slag particles or components of the respective refractory lining or spraying of the vessels as well as reaction products from metallurgical treatment steps.

[0007] This is achieved in particular by arranging appropriate fittings in a distribution trough, which generates a certain upward flow after the steel has been filled in such a way that the steel is flushed to the surface, so that particles which are lighter than the steel are absorbed into the slag or are bound by the slag.

[0008] A continuous casting plant is known from DE 33 37 739 A1. This continuous casting plant has a ladle holding and changing device (ladle turret), ladles, a tundish, a continuous casting mold, and a strand withdrawal device. A tundish is assigned to the ladle, which is filled with molten metal and is in the preparation position for transport to the casting position, for joint transport with the ladle. In this embodiment, the tundish is preferably inserted into the arm provided for receiving the ladle on the ladle turret below the ladle. The tundish and / or ladle are provided with means for detachable connection to one another.

[0009] From EP 0 119 853 A2 a tundish for continuous casting is known, wherein the tundish has a channeled induction heating device arranged on the side wall of the tundish, wherein the device comprises a channel communicating with an opening in the side walls of the tundish.

[0010] EP 0 140 217 A1 discloses a method and a device for changing the casting ladle and the intermediate container in a continuous casting plant.

[0011] From EP 0 726 115 A1 a tundish for receiving and filtering ferrous metal melts is known, which tundish has a discharge opening in the bottom area for withdrawing the metal melt after passing through a deflection and / or filtering device, wherein a ceramic filter is arranged in the tundish, which essentially covers the entire horizontal cross section of the tundish and can be removed in a manner known per se, which filter extends essentially in a horizontal direction and is provided with passage openings which are arranged in the essentially vertical flow direction of the metal melt through the tundish, whereby cleaning or filtering of metal melts can be achieved with a simple construction even for high casting speeds.EP 0 804 306 B1 discloses a device for regulating the flow of molten metal in a tundish to improve the separation of inclusions from the metal bath. For this purpose, a flow control dam is positioned downstream of a shock buffer, which has an upper portion configured to receive a flow of molten steel detaching from the shock buffer and divert it into at least one secondary flow flowing in a downstream direction toward the slag blanket and at least one secondary flow flowing in an upstream direction toward the slag blanket. Ultimately, this is a built-in dam designed to prevent short-circuit flow.

[0012] US Pat. No. 6,074,600 discloses a modification of a tundish dam to minimize turbulence. This is intended to reduce the formation of gas bubbles and slag inclusions, particularly during the initial filling of the tundish. For this purpose, a type of weir is arranged between the steel inlet of the tundish and the steel outlet of the tundish. The weir extends from the bath surface to the bottom, but is spaced from the bottom. Furthermore, a ramp is arranged between the weir and the steel outlet, while a second ramp is arranged upstream of the weir.

[0013] To prevent eddies in vessels containing molten steel, DE 10 2009 009 740 A1 describes the placement of vortex stones in the area of ​​the bottom outlets, with their knife edges extending into the vortex. The vortex stones consist of a circular segment-like, flat fixing part and the braking part with the knife edge. This one-piece component can be practically placed on the bottom outlet, or better yet, placed on a perforated stone and connected to it, because the inner diameter corresponds to that of the bottom outlet.

[0014] EP 3496882 B1 discloses a baffle plate for placement in a tundish to reduce the effects of misalignment of an impinging stream of molten steel entering the tundish. Furthermore, it is known to provide tundish troughs with a lowered floor from the steel inlet to the steel outlet, with a ridge or elevation placed on this inclined floor, sometimes also a stepped inclined floor, such that the steel inlet area forms a kind of pot, from which, after the pot is filled, the water flows over the ridge and then fills the entire tundish. This ridge also serves the purpose of ensuring turbulent flow and slightly extending the residence time of the steel in the tundish, and in particular, achieving contact with the slag layer.

[0015] From CN 103 25 465 Bl, a so-called turbulent flow controller for asymmetric use in the distributor is known, in which the shadow tube is arranged above this installation, whereby this installation is arranged in a plate-like manner with a slightly raised bottom on one side next to other shafts in the distributor.

[0016] A comparable installation is known from CN 102 000 791 A, which is located below the shroud and next to two ridges in the base of the distributor. However, the base of this installation, which has a cuboidal basic shape, is wave-shaped, with the steel from the shroud being cast into this structure and then emerging from it again above.

[0017] From KR 2003 00 52 756 A, a trough-shaped installation with its own vertical walls is known within the distributor. The shroud pipe terminates in a spring-like projection, and from there, the steel initially fills this trough-like structure before flowing into the rest of the distributor. The basic shape of the installation is roughly T-shaped, with the steel flowing through a reduced opening into the rest of the T-shaped sub-distributor.

[0018] A comparable installation is known from EP 0 804 306 B1, in which the steel is first poured into a trough located at the bottom, then exits laterally and encounters conventional embankment installations. CN 217 121 721 U also discloses a similar trough-like installation, but in this case the trough is more elongated-oval, but also with a wave-shaped bottom structure, so that the steel is first poured into this trough and then flows out of it into the rest of the distributor.

[0019] From "Numerical and Physical Study on New Simple Design of Subflux Flow Controller for One-Strand Tundish", Cwudzihski, Adam; Materials 2022, 15, 3756 ff., the influence on the flow using an asymmetric shadow tube was investigated, simulating various arrangements.

[0020] From "Physical and mathematical modeling of inclusion behavior in a tundish with gas curtain" ; Metallurgy and Materials 73(4), 531 - 538 2020, the influence of gas curtains in the inlet area was investigated, whereby the inlet area was additionally designed with walls hanging down from above and walls rising from below.

[0021] It was found that all these measures either calm the flow of the liquid melt, but then lead to a shorter residence time, or make it so turbulent that the particle loading is high.

[0022] The object of the invention is to provide a continuous casting process which leads to improved particle separation with minimal residence time and brings about a significant improvement in the purity of the molten steel.

[0023] The problem is solved by a method having the features of claim 1.

[0024] Advantageous further training is indicated in subclaims.

[0025] A further object is to create a continuous casting plant that leads to improved particle separation with minimal residence time. This object is achieved by a continuous casting plant having the features of claim 7.

[0026] Advantageous further training is indicated in the dependent claims.

[0027] A further task is to create an installation for a distributor in continuous casting, which will achieve improved particle separation with minimal residence time and a significant improvement in the degree of purity.

[0028] The problem is solved by an installation having the features of claim 12.

[0029] Advantageous further training is identified in dependent subclaims.

[0030] The inventors have recognized that by deliberately changing the flow conditions in the distributor, in particular the vortex structures, and increasing the residence time of the particles, in particular particles from non-metallic inclusions (NME) in the melt, the probability of separation of the unwanted particles is increased.

[0031] From "Physical and numerical flow simulation of continuous casting processes in high-temperature technology," Jürgen Odenthal, ISBN 3-937057-10-2, 1st edition 2004, it is known that the distributor flow induced from the ladle via the shroud without any internals in the distributor very often moves in the form of two counter-rotating vortex formations or rolls towards the plug or the pouring tube and the mold, which can be seen particularly in the image on page 129 of this publication. These two counter-rotating vortex formations are also called "double rolls."

[0032] The inventors have also discovered that while the usual internals in tundishes may slightly increase the residence time and can also create arbitrarily complex flow patterns, they do not lead to complete removal of unwanted particles. This may become even more important in the future, as steel production transitions from the traditional converter-based process of refining a mixture of scrap and pig iron and transferring this crude steel to a ladle, to electric steelmaking and upstream direct reduction. This process may result in a higher particle load.

[0033] The inventors have discovered that a singular helical flow or flow roller of the liquid metal in the tundish from the inlet, i.e., the shroud, to the outlet, i.e., the pouring plug, significantly reduces the number of inclusion frequencies per unit area in the cast slab. It is particularly advantageous if this flow extends over as much of the tundish cross-section as possible, i.e., starting from the inlet, over the shroud, over the tundish walls, extending to the bath surface, and then extending in a helical fashion forward to the outlet via the pouring tube. Preferably, at least 80%, preferably 90%, of the tundish cross-section should be encompassed by the singular flow roller.

[0034] According to the invention, this screw- or roller-shaped flow, which is referred to as single-roll, is generated by an asymmetric or eccentric positioning of the shadow tube in the XY plane of the distributor.

[0035] In general, the coordinate system is defined such that the Z-coordinate axis indicates a normal direction perpendicular to the surface of the distributor, the X-coordinate axis points in the direction of metal flow from the shroud tube towards the outlet in the distributor, and the Y-coordinate axis points in the transverse direction of the metal flow in the distributor towards the outlet. Furthermore, the geometry of the flow modifier can be adjusted to influence the flow. This can be achieved using internals such as a ramp or deflection boxes. The single-roll vortex structure is created by deflecting the flow asymmetrically to one side wall and not by the usual symmetrical deflection to both side walls or to the end wall.

[0036] Furthermore, gas purging devices such as purging beams can be used to reinforce the single-roll vortex structure.

[0037] Each of these measures can be carried out individually, several of these measures or all of these measures.

[0038] The asymmetric or eccentric positioning of the shroud in the XY plane of the tundish, or the correspondingly modified arrangement of the tundish under a ladle or other metallurgical vessel, results in the incoming steel hitting the bottom of the tundish and being naturally deflected upward by the opposite wall. In addition, the outflow through the pouring plug will lead to the formation of a helical single-roll flow structure.

[0039] Such an asymmetrical arrangement is preferably implemented after a sprue phase to avoid splashing. For example, the shadow tube is only moved sideways once it has penetrated the rising bath level.

[0040] Either the pan or the distributor or the pan and the distributor can be moved.

[0041] By generally modifying the distributor base to a concave, curved shape, the cylindrical flow can be supported and dead corners avoided. The jet from the shroud tube can enter the distributor in an area where the concave base transitions into a side wall, thereby being deflected.

[0042] The installation according to the invention for influencing the flow can, for example, be a ramp which is designed in the distributor such that an inclined impingement surface of the ramp points towards the shroud tube, so that the liquid metal flowing into the distributor first hits the impingement surface of this ramp and is deflected by this ramp according to the ramp gradient. However, it can also be a deflection box, i.e. a box-shaped device which is open at the top so that the flow from the shroud tube can flow in and which has an opening towards a side wall, whereby the flow from the shroud tube can be deflected accordingly. The installation can also have several openings, but these must all be directed towards only one side wall in order to generate the single roll flow according to the invention.

[0043] The base of the installation can be flat or curved, or even have grooves or other indentations. Furthermore, a nozzle-like pulsation of the melt can also be provided within the deflection box. In any case, however, the molten steel should be deflected toward a side wall, so that the liquid metal is deflected laterally and thus the roller flow is generated.

[0044] In both variants, a corresponding upward deflection will occur on the side wall opposite the ramp with respect to the opening of the installation, which will lead to the aforementioned single-roll flow structure. Of course, it is also possible to combine an asymmetric or eccentric positioning of the shroud tube with a corresponding ramp-shaped flow modifier, with the installation then being arranged in the area of ​​the asymmetric-eccentric positioning or, for example, being formed by a side wall of the distributor in this area. The impact surface can be inclined obliquely with respect to the xy direction, i.e., transversely to the width of the distributor. However, it can also have an inclination towards the outlet or opposite to the outlet.Preferably, an angle beta (ß) of -45° to 45°, preferably 0° to 45°, in particular 0° to 20°, preferably 0° to 10°, particularly preferably 1° to 5° in the direction of the x-axis, starting from the y-axis, can be set. This can influence the initial angle of the singular, helical flow roller and thus influence the residence time accordingly. In one embodiment, the angle can be set comparatively steep, e.g. 35° to 45°, in order to be able to specifically control the mixing time when the quality changes in the distributor. Increasing the angle can improve the quality when mixing liquid melts from electric furnaces with liquid melts from conventional blast furnaces.

[0045] Furthermore, the inclination angle alpha (o) can be set from greater than 20°, preferably greater than 30°, particularly preferably greater than 40°, relative to the y-axis in the z-axis direction in order to create an optimized deflection effect on the side wall. The angle alpha (o) can be selected to be less than 80°, preferably less than 70°, relative to the y-axis in the z-axis direction in order to be able to generate a singular, helical flow roller with increased vortex intensity in the side wall.

[0046] In the case of installation in the form of a deflection box, adjustments to the opening angle are also conceivable, with an angle of -60° to 60°, preferably -45° to 45°, relative to the y-axis in the direction of the z-axis being conceivable, i.e. an upward-facing opening in the direction of the bath level can also be provided. Additionally or alternatively, the opening can also have an angle of -45° to 45° in the direction of the x-axis, starting from the y-axis. This angle can also be achieved by offsetting the installation of the deflection box relative to the distributor. Furthermore, the impact surface can be scalloped or concave instead of flat.

[0047] In all cases, the installation is arranged in the area of ​​the shifted position of the shadow tube after the sprue.

[0048] In addition to these two measures, the opposite wall of the distributor, which deflects the flow upwards towards the covering slag, can of course also be designed with a bevel or a ramp in order to enable the most complete flow possible without turbulence in a dead corner formed by the bottom wall and the side wall.

[0049] Another possibility for creating a corresponding single-roll flow pattern is to inject gas from below, particularly into the wall or adjacent to the wall, particularly at a distance of 200 mm from the wall, which deflects the flow upwards, i.e., toward the cover slag. Such gas purges are also known from converters, for example. Inert gases are used as the purge gas.

[0050] This gas causes the rising gas bubbles to intensify the existing flow and thus entrain the material, i.e., the liquid metal, thus promoting the single-roll flow pattern. Furthermore, these gas bubbles can also specifically influence the liquid steel flow, directing it to the covering slag, thus facilitating particle deposition in the slag.

[0051] The gas purging measure can, of course, be combined with the first-mentioned measure of asymmetrical-eccentric positioning of the shroud tube or adjusting the geometry of the flow modifier to create a ramp, or with both measures, but can also be used alone to create a single-roll vortex structure. Gas purging can take place over a partial length of the distributor, at specific points, or at multiple locations.

[0052] The gas can be blown in through the bottom of the distributor and the bottom surface of the distributor, as is also the case in the converter with so-called purging stones.

[0053] In addition, it is possible to inject the gas through so-called purge bars installed at the bottom of the distributor, which are located adjacent to the wall that directs the metal flow upwards.

[0054] Such a flushing bar can of course also have a ramp-like bevel towards the flow or towards the center of the distributor, which additionally guides the flow upwards gently and without harsh transitions and then further strengthens it by the injected gas.

[0055] If the gas is injected at such a high rate that the induced flow from the distributor base to the bath level is 5 to 15, in particular 10, times as high as the longitudinal flow of the metal from the inlet to the outlet, a roller-like singular flow can be generated by the gas purging alone. For example, the longitudinal flow in a conventional distributor can be approximately 20 mm / sec. If a gas flow of, for example, 50 to 100 operating liters per minute is introduced at a side wall or adjacent to a side wall, and the steel flow in this area can be, for example, 100 to 200 mm / sec, then such a strong superposition can be generated that the desired single-roll flow according to the invention can develop.

[0056] The invention thus relates in particular to methods for the continuous casting of metal, in particular steel, wherein liquid metal is guided from a ladle, which is movably mounted, by means of a shroud into a continuous casting distributor and is guided from the continuous casting distributor via an outlet into a casting mold, wherein the distributor compensates for interruptions when the ladles are changed and wherein the ladles are mounted in a movement device, characterized in that the ladle is positioned during the sprue, i.e. during the first filling of the liquid metal into the distributor, in such a way that the shroud is arranged in the region of a longitudinal center of the distributor and after reaching a desired bath level, the ladle or the distributor or the ladle and the distributor are moved and in particular displaced laterally in such a way that in order to form a single roller-like flow of the metal in the distributor,the shadow pipe is arranged outside the longitudinal center of the distributor offset to a side wall.

[0057] A further development provides that the movement of the ladle or the distributor or the ladle and the distributor comprises one, several or all of: rotating, pivoting, lifting, lowering and / or tilting.

[0058] A further development provides for the shadow tube to be lowered into the distributor before or during the sprue.

[0059] A further development provides that the ladle and distributor are offset from each other when the shadow tube pierces the bath level or dips into the melt.

[0060] A further development provides that for the purpose of offsetting the ladle turret is rotated or shifted by the amount of the desired deflection.

[0061] A further development provides for a device to be arranged below the impingement area of ​​the liquid metal in the distributor, which device supports a singular, directed flow after lateral displacement. Another aspect relates to a continuous casting plant for continuous metal casting, comprising at least one ladle and a distributor arranged thereunder, wherein a ladle outlet for liquid metal into the distributor is arranged on the ladle, and the distributor has an installation below the ladle outlet with a bottom wall and at least two parallel ribs projecting up from the bottom wall.

[0062] A further development provides that at least two ribs are formed, which form a plurality of chambers or grooves for directing the flow of the liquid metal.

[0063] A further development provides that the installation runs from a side wall of the distributor in the direction of the longitudinal center or Y-axis of the distributor, wherein the at least two ribs run substantially parallel or at an angle thereto.

[0064] A further development provides that the bottom wall of the installation is flat or convexly curved or concavely curved and / or formed with a contour or with depressions.

[0065] A further development provides that the distributor is a longitudinal or transverse distributor or V-distributor.

[0066] A further aspect relates to an installation, in particular for use in a distributor of a continuous casting plant, wherein the installation is designed with at least one rib projecting up from the bottom wall, which is oriented at an angle α of -45° to 45°, preferably 0° to 45°, in particular 0° to 20°, preferably 0° to 10°, particularly preferably 1° to 5° in the x-axis direction, starting from the y-axis of the distributor. A further development provides that at least two ribs are formed, which form at least one chamber or channel for deflecting the flow of the liquid metal.

[0067] A further development provides that the bottom wall of the installation is flat or convexly curved or concavely curved.

[0068] A further development provides that the bottom wall is formed obliquely and in particular rises transversely to the longitudinal extent of the distributor, so that a sloping ramp is formed.

[0069] A further development provides that a rear wall is arranged transversely to the channels or chambers away from the floor wall, which closes off the channels or chambers on one side.

[0070] A further development provides that the rear wall ends with a side wall of the distributor or is formed by it.

[0071] A further development provides for the ramp to slope downwards from the rear wall.

[0072] A further development provides that the rear wall projects upwards over the upward-facing front edges of the ribs.

[0073] A further development provides for the front edges of the ribs to run horizontally or sloping.

[0074] A further development provides for the installation to be designed with a circular curve relative to the bottom wall in order to follow the rotation of the ladle turret. A further development provides for side walls of the installation to be arranged on the side edges of the bottom wall, which run transversely to the longitudinal extension of the distributor, and which extend from the rear wall toward the longitudinal center of the distributor.

[0075] A further development provides that the side walls protrude upwards over the upward-facing front edges of the ribs.

[0076] A further development provides that the front edges of the ribs run horizontally or sloping or parallel to the bottom wall.

[0077] A further development provides for the front edges to be convex or concave.

[0078] A further development provides that the installation is made of a refractory material, in particular a basic refractory material comprising one, several or all materials from the group: AI2O3, MgO, CaO, (MgCa)Ü2, carbon, hydraulic binders.

[0079] A further development provides that the bottom wall has anchor elements on the underside for pressing or pouring into the bottom material of a distributor.

[0080] A further development provides that the bottom wall is designed to be flat in the area of ​​the sprue and thus in the area of ​​the longitudinal center of the distributor and rises in a ramp-like manner at a distance from this area towards the rear wall, so that a flat and a ramp-like area are formed.

[0081] The invention is explained by way of example with reference to a drawing. It shows:

[0082] Figure 1: the state of the art with two counter-rotating vortex formations; Figure 2: a highly schematic view of a continuous casting plant;

[0083] Figure 3: a longitudinal section through an installation as a box;

[0084] Figure 4: a top view of the installation according to Figure 2;

[0085] Figure 5: a cross-section through the installation according to Figure 2; Figure 6: a perspective view of an installation;

[0086] Figure 7: a longitudinal section through a distributor with installation;

[0087] Figure 8: the distributor according to Figure 7 in a cross section with a central shadow tube in the sprue;

[0088] Figure 9: a distributor with a shifted shadow pipe in perspective view;

[0089] Figure 10: a longitudinal section through a distributor with the forming single roll;

[0090] Figure 11: a cross-section through the distributor according to Figure 10 with a displacement of the shadow pipe Figure 12: an example of an installation with anchoring options:

[0091] Figure 13: highly schematic view of a first embodiment of anchor elements;

[0092] Figure 14: a highly schematic view of a second embodiment of anchor elements; Figure 15: a highly schematic view of a third embodiment of anchor elements in a plan view;

[0093] Figure 16: highly schematic side view of the third embodiment of anchor elements.

[0094] As can also be seen from the figures, the method according to the invention for the continuous casting of metal, in particular steel, provides for conducting liquid metal from a ladle 1, which is movably mounted, by means of a shadow pipe 17 into a continuous casting distributor 2, which is then conducted from the continuous casting distributor 2 via an outlet into a casting mold.

[0095] As is known, the task of the distributor 2 is to compensate for interruptions when the ladles 1 are changed. For the ladles to be changed, the ladles 1 are mounted in a so-called ladle turret and can be pivoted via the respective distributor 2.

[0096] According to the invention, to form the aforementioned screw-like or roller-like flow, the ladle 1 is positioned during the sprue, i.e., during the first pouring of the liquid metal into the distributor 2, such that the shadow tube 17 is arranged in the region of a transverse center of the distributor 2. After reaching a desired bath level, the ladle 1 or the distributor 2, or the ladle and the distributor 2, are moved, and in particular shifted laterally, such that, to form a single roller-like flow of the metal in the distributor, the shadow tube 17 is arranged offset from a side wall 9 outside the longitudinal center of the distributor 2. This movement can be effected, for example, by a corresponding pivoting movement of the ladle turret. In principle, the movement of the ladle 1 or the distributor 2, or of the ladle 1 and the distributor 2, can comprise one, several, or all of: rotating, pivoting, raising, lowering, or tilting.

[0097] For example, the shadow tube 17 can be lowered into the distributor 2 before or during the sprue. This serves to prevent splashing.

[0098] For example, it is possible that ladle 1 and distributor 2 are displaced relative to each other when the shadow tube 17 penetrates the bath surface 19 or dips into the melt. In this case, splashes are no longer to be expected when the displacement movement occurs.

[0099] In order to support the formation of the desired flow and to avoid undesirable turbulence in the impact area of ​​the pouring jet, a device 4 can be arranged in the impact area of ​​the liquid metal in the distributor 2, which device supports a singular, directed flow after the lateral displacement.

[0100] The continuous casting plant for continuous metal casting thus comprises at least one ladle 1 and a distributor 2 arranged underneath, with a ladle outlet 3 for liquid metal into the distributor 2 being arranged on the ladle 1. The ladle outlet 3 comprises, in particular, a so-called shroud 17, through which the pouring stream is directed into the distributor 3 in a shielded manner.

[0101] The distributor 2 has an installation 4 at least below the ladle outlet 3 at the point where it is positioned after pivoting. The installation 4 is thus offset from the longitudinal center of the distributor 2 and offset from a side wall 9 of the distributor. In particular, it can also be arranged adjacent to a side wall 9 and even be part of the side wall 9. The installation 4 has a bottom wall 5 and at least two parallel ribs 6 projecting up from the bottom wall 5. These ribs 6 can be used to generate a directed flow, but also to reduce or prevent the formation of undesirable turbulence.

[0102] In particular, at least two ribs 6 are formed, which form a plurality of chambers 7 or grooves 8 for directing the flow of the liquid metal.

[0103] The installation 4 runs, for example, from a side wall 9 of the distributor 2 in the direction of the longitudinal axis or transverse center or Y-axis of the distributor 2, wherein the at least two ribs 6 run substantially parallel or at an angle thereto.

[0104] The bottom wall 5 of the installation 4 can be flat or convexly curved or concavely curved and / or formed with a contour or with depressions in order to influence the flow.

[0105] The continuous casting plant can be designed so that the distributor 2 is a longitudinal or transverse distributor or V-distributor.

[0106] The at least one rib 6 of the installation 4 is oriented in particular at an angle α of -45° to 45°, preferably 0° to 45°, in particular 0° to 20°, preferably 0° to 10°, particularly preferably 1° to 5° in the x-axis direction, starting from the y-axis of the distributor 2. If there is more than one rib 6, these preferably run substantially parallel to one another.

[0107] With multiple ribs 6 and at least two ribs 6, these define a chamber 7 or channel 8 between them for deflecting the flow of the liquid metal. The bottom wall 5 of the insert 4 can be designed to be inclined to deflect the pouring stream and, in particular, can rise transversely to the longitudinal extension of the distributor 2, forming a sloping ramp 10.

[0108] In addition, a rear wall 11 can be arranged transversely to the channels 8 or chambers 7 away from the bottom wall 5, which closes off the channels 8 or chambers 7 on one side.

[0109] The rear wall 11 can terminate with a side wall 9 of the distributor 2 or be formed by it.

[0110] If the bottom wall 5 is designed as a ramp 10, the ramp 10 slopes down from the rear wall 11.

[0111] In this case, the rear wall 11 can project upwards over the upwardly facing front edges 12 of the ribs 6, thus projecting above them in height.

[0112] The upwardly facing front edges 12 of the ribs 6 can run horizontally or sloping over their length.

[0113] The insert 4 can be curved in a circular manner relative to the bottom wall 5. This curve corresponds to a segment of a circle. This takes into account the fact that the ladle turret pivots around a vertical axis and thus describes a circular path. This makes the most sense when the bottom wall 5 of the insert 4 extends from a gate point to the point reached after pivoting.

[0114] In this case, the bottom wall 5 can be designed to be flat in the region of the sprue and thus in the region of the longitudinal center 15 of the distributor and can rise in a ramp-like manner at a distance from this region towards the rear wall 11, so that a flat and a ramp-like region are formed.

[0115] Side walls 14 of the installation can be arranged on the side edges 13 of the bottom wall 5 of the installation 4, which run transversely to the longitudinal extension of the distributor 2. These can be arranged with or without a rear wall 11. They run, in particular, parallel to ribs 6 (if present) and can essentially represent additional outer ribs.

[0116] If a rear wall 11 is present, the side walls run from the rear wall 11 in the direction of the longitudinal center 15 of the distributor 2.

[0117] The side walls 14 can also protrude upwards beyond the upwardly facing front edges 12 of the ribs 6. This creates a box enclosed on three sides with ribs 6 inside.

[0118] In this case, the upwardly facing end edges 12 of the ribs 6 can also run horizontally or slopingly or parallel to the bottom wall 5. A convex or concave shape of the end edges 12 over their length is also possible.

[0119] The insert 4 is made of an appropriate refractory material. In particular, a basic refractory material comprising one, several, or all materials from the group: Al2O3, MgO, CaO, (MgCa)O2, carbon, and hydraulic binders.

[0120] For mechanically reliable integration of the installation into the refractory material forming the distributor base, at least one anchor element 16 can be provided on the underside of the base wall 5. The anchor element 16 can, in particular, be designed to be pressed or cast into the base material of a distributor 2. The wear lining of a distributor is usually injection-molded, so this is easily possible in a wet or green state.

[0121] Such anchor elements are shown by way of example in Figures 12 to 16. Here, a base wall 5 of the device 4 is shown in a highly simplified form, from which corresponding anchor elements 16 protrude or extend on the base side. The anchor elements 16 (Figures 13 to 16) can be pins or rods 16a (Fig. 10) or triangular projections 16b (Fig. 11) or a protruding cross 16c made up of two intersecting strips 16d (Figs. 12, 13). The rods 16a or projections 16b can be arranged individually or in groups, symmetrically distributed evenly or distributed without a system on the base 5. In addition, the anchor elements can also be arranged in combination with one another on the base 5.

[0122] Furthermore (Figure 12), the bottom wall 5 of the device can be formed with one or more recesses 16e, through which the device is pressed into the soft concrete and through which the concrete passes and embeds the device. Edge strips 16f, which protrude laterally beyond the bottom wall 5, can also be overflowed by the concrete when pressed into the concrete, embedding the device. In Figure 13, the recesses 16f are shown on the bottom wall and the rear wall for clarity, but the designs are intended and suitable for the bottom wall.

[0123] The distributor 2 is an elongated, preferably trough-like container with two opposite end walls 20, 21 and the two side walls 9 connecting the end walls 20, 21.

[0124] In addition, the distributor 2 has a base 22, with an inlet area 23 and an outlet area 24 provided along a central axis of the distributor 2. The inlet area 23 is arranged adjacent to an inlet-side end wall 20, while the outlet area 24 is formed adjacent to an outlet-side end wall 21, so that incoming steel generally flows through the vessel following the longitudinal extension of the distributor 2. However, the distributor can also be shaped differently, for example, V-shaped or with multiple fingers or multiple outlets.

[0125] The bottom 22 of the distributor 2 can deepen diagonally from an inlet area 23 to an outlet area 24, whereby diagonally means that the depth becomes deeper compared to a bath level 19.

[0126] In the outlet area 24, an outlet 25 with a pouring tube 26 is arranged in the bottom. The pouring tube 26 opens into a mold 27 in which the metal is cooled until solidification occurs. The strand 28 emerges from the bottom of the mold 27 and is deflected by refractory rollers 29, reaching a straightening zone 30. After the straightening zone 30, the strand 28 is cut into slabs 32 by flame cutters 31.

[0127] From Figures 9 and 11, it can be seen that the shadow tube 17 can be displaced eccentrically, i.e., offset relative to one of the walls 9, in the distributor 2. It may be sufficient for the shadow tube 17 to be displaced eccentrically relative to a wall 9, thus allowing the metal jet to flow along the inside of the wall 9, thereby forming a desired helical flow pattern.

[0128] In addition, the outlet 25 can also be arranged in the same direction as the shroud 4, offset from the transverse center of the distributor base 22. This makes it possible to better maintain the helical roller flow up to the outlet 25. It then does not constrict as much as in the prior art (Figure 1).

[0129] Figures 3 to 5 show an inflow of the metal stream, with the installation 4 in this case being designed as a deflection box with an opening 33 to a side wall 7. The melt is introduced via the shadow tube 4 through an upper opening 34 and deflected from the upper opening 34 of the deflection box to the lateral opening 33, so that the liquid metal is deflected laterally and the roller flow is thereby generated. In all figures, a deflection to the left side wall 9 is shown as an example; of course, a mirror-inverted deflection to the right side wall 9 is equally possible and would lead to the same helical roller flow according to the invention.

[0130] The invention therefore has the advantage that both the filling and emptying of the distributor can take place without an accumulation of inclusions and, in addition, the filling efficiency of the distributor is improved.

Claims

Patent claims 1. A method for the continuous casting of metal, in particular steel, wherein liquid metal is guided from a ladle, which is movably mounted, by means of a shadow tube into a continuous casting distributor and is guided from the continuous casting distributor via an outlet into a casting mold, wherein the distributor compensates for interruptions when the ladles are changed and wherein the ladles are mounted in a moving device, characterized in that the ladle is positioned during the sprue, i.e. during the first filling of the liquid metal into the distributor, such that the shadow tube is arranged in the region of a transverse center of the distributor and after reaching a desired bath level, the ladle or the distributor or the ladle and the distributor are moved and in particular shifted laterally such that in order to form a single roller-like flow of the metal in the distributor,the shadow pipe is arranged outside the transverse center of the distributor offset to a side wall.., 2. Method according to claim 1, characterized in that the movement of the ladle or the distributor or the ladle and the distributor comprises one, several or all of: rotating, pivoting, lifting, lowering, tilting.

3. Method according to claim 1 or 2, characterized in that the shadow tube is lowered into the distributor before or during the sprue.

4. Method according to one of the preceding claims, characterized in that the ladle and distributor are offset from one another when the shadow tube pierces the bath level or dips into the melt.

5. Method according to one of the preceding claims, characterized in that for the purpose of offsetting the ladle turret is rotated or shifted by the amount of the desired deflection.

6. Method according to one of the preceding claims, characterized in that a device is arranged below the impact area of the liquid metal in the distributor, which device supports a singular, directed flow after the lateral displacement.

7. Continuous casting plant for metal continuous casting, comprising at least one ladle (1) and a distributor (2) arranged thereunder, wherein a ladle outlet (3) for liquid metal is arranged in the distributor (2) and the distributor (2) has an installation (4) below the ladle outlet (3) with a bottom wall (5) and at least two parallel ribs (6) projecting up from the bottom wall (5).

8. Continuous casting plant according to claim 6, characterized in that at least two ribs (6) are formed, which form a plurality of chambers (7) or channels (8) for directing the flow of the liquid metal.

9. Continuous casting plant according to claim 6 or 7, characterized in that the installation (4) extends from a side wall (9) of the distributor (2) in the direction of the longitudinal axis or transverse center or Y-axis of the distributor (2), wherein the at least two ribs (7) extend substantially parallel or at an angle thereto.

10. Continuous casting plant according to one of claims 6 to 8, characterized in that the bottom wall (5) of the installation (4) is flat or convexly curved or concavely curved and / or formed with a contour or with depressions.

11. Continuous casting plant according to one of claims 6 to 9, characterized in that the distributor (2) is a longitudinal or transverse distributor or V-distributor.

12. Installation, in particular for use in a distributor of a continuous casting plant, characterized in that the installation (4) is designed with at least one rib (6) projecting from the bottom wall (5) which is inclined at an angle o of -45° to 45°, preferably 0° to 45°, in particular 0° to 20°, preferably 0° to 10°, particularly preferably oriented from 1° to 5° in the direction of the x-axis starting from the y-axis of the distributor (2), wherein for the spatial orientation the Z-coordinate axis denotes a normal direction which runs perpendicular to the surface of the distributor, the X-coordinate axis points in the metal flow direction from the shadow tube in the direction of the outlet in the distributor and the Y-coordinate axis points in the transverse direction of the metal flow in the distributor in the direction of the outlet.

13. Installation according to claim 12, characterized in that at least two ribs (6) are formed, which form at least one chamber (7) or channel (8) for deflecting the flow of the liquid metal.

14. Installation according to claim 12 or 13, characterized in that the bottom wall (5) of the installation (4) is flat or convexly curved or concavely curved.

15. Installation according to one of claims 12 to 14, characterized in that the bottom wall (5) is formed obliquely and in particular rises transversely to the longitudinal extent (9) of the distributor (2), so that a sloping ramp (10) is formed.

16. Installation according to one of claims 12 to 15, characterized in that a rear wall (11) is arranged transversely to the channels (8) or chambers (7) away from the bottom wall (5), which closes off the channels (4) or chambers (5) on one side.

17. Installation according to one of claims 12 to 16, characterized in that the rear wall (11) terminates with a side wall of the distributor (2) or is formed by it.

18. Installation according to one of claims 12 to 17, characterized in that the ramp (10) slopes down from the rear wall (11).

19. Installation according to one of claims 12 to 18, characterized in that the rear wall (11) projects upwards beyond upwardly facing end edges (12) of the ribs (6).

20. Installation according to one of claims 12 to 19, characterized in that the front edges (12) of the ribs (6) run horizontally or sloping.

21. Installation according to one of claims 12 to 20, characterized in that the installation is designed to be circularly curved with respect to the bottom wall (5) in order to follow the rotation of the ladle turret.

22. Installation according to one of claims 12 to 21, characterized in that on side edges (13) of the bottom wall (5), which are transverse to the longitudinal extent of the distributor (4) side walls (14) of the installation (4) are arranged, which run from the rear wall (11) in the direction of the longitudinal center (15) of the distributor (2).

23. Installation according to one of claims 12 to 22, characterized in that the side walls (14) project upwards beyond upwardly facing end edges (12) of the ribs (6).

24. Installation according to one of claims 12 to 23, characterized in that the front edges (12) of the ribs (6) are horizontal or sloping or parallel to the bottom wall (5) run.

25. Installation according to one of claims 12 to 24, characterized in that the end edges (12) are convex or concave.

26. Installation according to one of claims 12 to 25, characterized in that the installation is made of a refractory material, in particular a basic refractory material comprising one, several or all materials from the group: Al2O3, MgO, CaO, (MgCa)O2, carbon, hydraulic binders 27. Installation according to one of claims 12 to 26, characterized in that the bottom wall (5) has anchor elements (16) on the underside for pressing or pouring into the bottom material of a distributor (2).

28. Installation according to one of claims 12 to 27, characterized in that the bottom wall (5) is designed to be flat in the region of the sprue and thus in the region of the transverse center (15) of the distributor and, at a distance from this region, rises in a ramp-like manner towards the rear wall (11), so that a flat and a ramp-like region are formed.

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