KR102319760B1 - Flow rate control in continuous casting - Google Patents

Abstract

An apparatus (1) for controlling a flow rate in a mold (2) for continuous casting of metal comprises: at least two first front cores (3) having an associated first magnetic coil (4) disposed on one side of the mold; at least two second front cores (5) having an associated second magnetic coil (6) disposed on opposite sides of the mold and substantially aligned with said first front core; an outer magnetic loop (7, 8, 9) connecting the second front core to the first front core so that one-way magnetic flux can pass through the mold from the first front core to the second front core and vice versa; and a control interface 14 that enables independent control of the two subsets of the first magnetic coil.

Description

Flow rate control in continuous casting

The present invention relates to the field of continuous casting of metals, and in particular proposes a device for controlling the flow rate in a thin slab caster.

Stability control is essential in high-speed continuous foil slab casting processes. Modern high-productivity thin slab casting machines can have throughputs of 8 tonnes per minute or more. In this scenario, the rate of inflow of molten steel is high as it leaves the submerged entry nozzle (SEN) and towards the mold, which leads to a strong turbulence effect, which is unstable, fluctuating and time-varying in the upper part of the strand. risk of negative flow patterns. Reducing this effect is important to obtain homogeneous and constant thermal and flow conditions so that the fluid steel solidifies uniformly in the mold.

In today's continuous casting machines, slab production is often diversified into various grades and dimensions. To accommodate these various casting machine outputs, the operation of the thin slab casting machine dynamically changes according to the width, casting speed, shape of SEN, SEN immersion, superheat, mold funnel shape, etc. A difficult aspect of the process is to provide an equivalent solidification environment irrespective of the caster parameters under conditions where homogeneous solidification is preferred. High-speed thin slab casting machines are particularly at risk of excessive meniscus flow rates, fluctuations, turbulence and deflection flows, which can lead to mold powder entrainment or fluctuations in initial shell solidification.

Electromagnetic brake (EMBR) not only brakes the flow of molten steel in the mold, but also allows this braking force to be adjusted to an appropriate level according to the incoming flow rate of steel by controlling the current to the brake, so these potential It provides an excellent alternative to dynamically offset the deterioration of phosphorus quality.

Traditional deterministic (or open-loop) EMBR control applies different currents to the EMBR at different casting conditions. Appropriate current settings are usually found by tests evaluating steel quality and process stability, and by numerical and physical modeling. Besides being cumbersome, time-consuming and expensive, these methods work on a large scale and lack the sharpness of handling local and special events.

EP2633928B1 attempts to improve EMBR control by placing a plurality of independently controllable magnetic brakes in different areas of the casting mold. This allows the operator to offset left/right asymmetry or depth gradients in the molten metal flow with a certain degree of freedom. However, by the configuration of the magnetic poles, the magnetic brake can only apply a magnetic field in which the direction of at least one local magnetic field in the mold is opposite to that of another local magnetic field in the mold. That is, a braking device according to EP2633928B1 having one left braking region and one right region can be operated in a mode such as (+,-) mode, (-,+) mode, but for example (+,+ ) or (+,0) mode.

One object of the present invention is to propose a flow rate control device which enables a more versatile, flexible and/or more adaptable flow rate control in a mold for continuous casting of metals. This object is achieved by the invention as defined by the independent claims.

In a first aspect, there is provided an apparatus for controlling a flow rate in a mold for continuous casting of metal, comprising: at least two first front cores having an associated first magnetic coil disposed on one side of the mold; at least two second front cores substantially aligned with the first front core and having an associated second magnetic coil disposed on an opposite side of the mold; and an outer magnetic loop connecting the second front core to the first front core such that the unidirectional magnetic flux can pass through the mold from the first front core to the second front core and vice versa. According to one embodiment, the flow rate control device further comprises a control interface enabling independent control of the two subsets of the first magnetic coil.

Due to the combination of an external magnetic loop and a control interface that allows a portion of the first magnetic coil to be controlled independently of the rest of the first magnetic coil, the flow rate control device is capable of providing one-way magnetic flux with different intensities in different regions of the mold. can The one-way magnetic flux is a flux directed from the mold side proximate to the first front core to the mold side proximate to the second front core anywhere, unless locally zero, or anywhere from the mold side proximate to the second front core to the first front core. It is the magnetic flux toward the mold side. The presence of an external magnetic loop allows for the generation of a one-way magnetic flux, but it is also possible to apply a flux of the (+,-) or (-,+) type, where the net flux is zero (e.g. left/right magnitude) is equal) or non-zero (eg if left/right sizes are different). The presence of an external magnetic loop releases the limitation described in EP2633928B1 that the direction of at least one local magnetic field in the mold is opposite to the direction of another local magnetic field in the mold.

In one embodiment, the control interface enables independent control of two or more subsets of the second magnetic coil. This is in addition to the independent control of two or more subsets of the first magnetic coil that the control interface enables. An effect of the controllability of the second magnetic coil is that the geometry and/or local strength of the magnetic flux can be more precisely controlled.

The subset of the first magnetic coil and/or the subset of the second magnetic coil may be arranged differently relative to the lateral direction of the mold. For example, in an embodiment wherein the flow rate control device comprises one left and one right first front core and one left and one right second front core, the two left magnetic coils associated with the two right magnetic coils associated with it It can be controlled independently of the coil. This may allow for a more precise adjustment of the applied magnetic flux for the lateral direction, and thus a more precise control of the flow rate, including the flow geometry.

In a variant, the flow rate control device may comprise two left and two right first front cores and two left and two right second front cores, the two left first front cores being in the vertical direction of the mold. They can be placed at different heights to provide good coverage. Likewise, each of the right first, left second and right second front cores may be disposed at different heights. According to this variant, the magnetic coils associated with the two left first front cores can be controlled independently of the magnetic coils associated with the two right first front cores. also (i) between the magnetic coils associated with the upper and lower left first front cores; (ii) between the magnetic coils associated with the upper and lower left second front cores; and (iii) the magnetic coils associated with the upper and lower right first front cores. between, (iv) between the magnetic coils associated with the upper and lower right second front cores, and/or (v) between the magnetic coils associated with the two left second front cores and the magnetic coils associated with the two right second front cores. There is optional (but not required) control independence.

In the embodiment described above, independent control can be achieved by the fact that the control interface includes electrical terminals for energizing the magnetic coils of each subset. That is, each subset is provided with electrically isolated terminals (or pairs of terminals). Alternatively, if the control interface comprises a processor and is realized at least partially in software, control independence may be achieved by software instructions to this effect.

In one embodiment, the control interface is configured to coordinately control a magnetic coil associated with the aligned pair of anterior cores. For example, the magnetic coil associated with the (upper) left first front core and the magnetic coil associated with the (upper) left second front core are cooperatively controlled. These cores may be aligned in the sense that their axes of symmetry, generally parallel to the transverse direction of the mold, substantially coincide. Cooperative control is to be understood as meaning that substantially equal or proportional control signals or excitation currents are applied to both magnetic coils and thus the resulting magnetic flux through both coils is similar or substantially equal. This can be achieved by providing the control interface with a common electrical terminal (or terminal pair) for exciting one of the magnetic coils that is to be controlled in a cooperative manner. Likewise, in the case of a control interface comprising a processor, cooperative control may be achieved by providing corresponding software instructions.

In one embodiment, the magnetic coil is controlled based on sensor data regarding the temperature distribution or temperature gradient within the mold or regarding the characteristics of the meniscus. The sensor data may have spatial resolution for the lateral direction of the mold. That is, the sensor data may include at least one left and one right value. In embodiments where the spatial resolution is much finer, there may be three or more different sensor data values corresponding to the same number of points or areas distributed along the lateral direction of the mold.

In one embodiment, the first and/or second front core is provided with a flux-forming element. This may result in spatially non-uniform magnetic flux passing through the mold. The flux-forming element may be reconfigurable.

In one embodiment, the outer magnetic loop includes first and second level cores that can be withdrawn from the mold to allow for mold exchange or maintenance, and an outer yoke. This provides a magnetic circuit capable of channeling the magnetic field in a substantially closed loop, i.e. from the second front core through the second level core, the outer yoke and the first level core to the first front core, the magnetic flux being It passes from the core across the mold to reach the second front core.

In one embodiment, the flow rate control device is supported so that it can move independently of the mold. Typically, in order to make the casting run more smoothly, the mold is mounted on a vibrating table. The flow rate control device, which does not benefit from experiencing vibrations, must be mounted on a support structure other than the vibration table. As the weight that the vibrating table has to bear is thus reduced, the vibrating table can be simpler in design, more economical to operate, and less prone to wear and fatigue.

In a second aspect, there is provided a system for continuous casting of metal comprising a mold, a source of molten metal, and a flow rate control device having the above characteristics. Preferably, the system is a thin slab casting machine.

In general, all terms used in the claims are to be interpreted according to their ordinary meaning in the art, unless explicitly defined otherwise herein. The terms flow rate control device, electromagnetic brake device, electromagnetic brake (EMBR) and device may be used interchangeably herein for simplicity. All references to "an element, device, component, means, step, etc., which are modified by the article/definitive article" are, unless otherwise specified, a reference to at least one example of that element, apparatus, component, means, step, etc. should be interpreted openly. The steps of any method disclosed herein need not be performed in the exact order disclosed unless otherwise specified.

Aspects and embodiments are now described by way of example with reference to the accompanying drawings.
1 and 2 are perspective, partially cutaway views of a thin slab casting machine having a single magnetic coil on each side of a casting mold.
3 is a schematic plan view of a thin slab casting machine including an outer yoke, the magnetic coils on either side of the mold cannot be independently controlled.
4 is a schematic plan view of a thin slab casting machine including independently controllable left and right magnetic coils on each side of a mold, and two inner yokes arranged so that the magnetic field directions on the left and right are opposite to each other;
5 is a schematic plan view of a thin slab casting machine including an external yoke and independently controllable left and right magnetic coils on each side of a mold, in accordance with an embodiment of the present invention.
6 is a schematic front view of the configuration of a flux-forming element disposed on a front core of a thin slab casting machine;
7A is a perspective view of a front core of a thin slab casting machine including a configuration of flux-forming elements;
Fig. 7b is a schematic front view of the construction of the flux-forming element shown in Fig. 7a;
8 is a schematic plan view of a thin slab casting machine including an external yoke and independently controllable left and right magnetic coils on each side of the mold, in accordance with an embodiment of the present invention, showing the processor, control interface and sensors;
Fig. 9 is a perspective view of a casting mold in which a plurality of optical fibers are horizontally arranged on the walls thereof to sense the temperature distribution within the mold;
10 is a side cross-sectional view (lower part) of a SEN for a thin slab casting machine, showing the velocity distribution v(x) and meniscus height h for the lateral direction x, and a cross-sectional view through line BB ( upper part).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Aspects of the present invention will now be more fully described with reference to the accompanying drawings in which specific embodiments of the present invention are shown.

However, these aspects may be embodied in many different forms and should not be considered limiting; Rather, these examples are provided by way of example so that this invention will be thorough and complete, and will fully convey the scope of all aspects of the invention to those skilled in the art. As summarized in the following description of reference numerals, like reference numerals refer to like elements throughout.

1 and 2, cutaway views with different amounts of opaque objects removed, show a thin slab caster system with an electromagnetic braking device of a universal type. In operation, the SEN 13 ejects steel or molten metal such as ferrous or non-ferrous alloys into the mold 2 . Due to the downward force of its own gravitational force and the weight of the metal subsequently added upwards in the mold 2 , the metal moves vertically to reach the cooler region of the mold 2 , where it slowly solidifies (crystallizes), eventually It leaves the mold 2 as a continuous slab. The mold 2 may be made, for example, of copper, optionally with an inner surface lubricated or coated to control friction, and may have a cross-section measuring about 100 mm×1400 mm, with a diameter of 5.5 m/min. It may be suitable for casting speed.

The electromagnetic braking device shown in FIGS. 1 and 2 includes a first front core 3 (visible only in FIG. 2 ) on the proximal side of the mold 2 and a second front core 5 on the distal side of the mold 2 . ) (only visible in FIG. 2). One magnetic coil 4 , 6 surrounds each front core 3 , 5 and is thus associated with the front core 3 , 5 . An electrical terminal 10 for exciting the magnetic coil 4 at least on the proximal side is shown. The divided proximal parts 3.1 , 5.1 of the first and second front cores 3 , 5 extend to the surface of the mold 2 through corresponding passages of the refrigerant channels 11.1 , 12.1 configured to remove excess heat. . The electromagnetic braking device further comprises first and second level cores 8 , 9 which interface with the front core 3 , 5 and further interface with a double-sided magnetic yoke 7 which serves to close the magnetic circuit. do. The interface of the magnetic circuit may be solid or may have an air gap. The magnetic yoke 7 and the level cores 8 , 9 may be of a ferromagnetic material such as iron.

)에 실질적으로 수직한 정적 자기장(

)에 노출된다. 따라서 금속은

와 실질적으로 반대되는 제동 와전류 힘The hollow arrows indicate the direction of the local magnetic flux while the magnetic coils 4 and 6 are energized. Under the action of the excited magnetic coils 4 , 6 , the metal flow in the mold 2 under the SEN 13 is

) a static magnetic field substantially perpendicular to (

) is exposed to So the metal

Braking eddy current force substantially opposite to

는 국소 전기장이고

는 적절한 단위의 전도율이다. 도 1 및 도 2에 도시된 전자기 제동 장치는 몰드(2)의 다른 측방향 위치에서 유동의 독립적인 제어를 가능하게 하지 못할 수 있다.will be experienced, and here

is the local electric field

is the conductivity in appropriate units. The electromagnetic braking device shown in FIGS. 1 and 2 may not enable independent control of the flow in different lateral positions of the mold 2 .

3 is a schematic plan view of a thin slab casting machine with an electromagnetic braking device comprising an outer yoke 7 . This thin slab casting machine has characteristics similar to those described with reference to FIGS. 1 and 2 . An electromagnetic braking device equipped with a thin slab casting machine comprises a single magnetic coil 4 , 6 on each side of the mold 2 . The magnetic coil is energized according to a signal generated by the connected control interface 14 to provide a magnetic flux similar to that shown by the solid arrow. Although the control interface 14 can enable independent control of the two magnetic cores 4 and 6 , it is impossible to impart transverse magnetic fields of different strengths to the left and right sides of the mold 2 .

4 shows left and right first front cores 3a, 3b associated with left and right first magnetic coils 4a, 4b as well as left and right second front cores 5a, 5b associated with left and right second magnetic coils 6a, 6b. A top view of another prior art casting system having an electromagnetic braking device. The magnetic flux can be circulated by the first inner magnetic yoke 15 interfacing with the left and right first front cores 3a, 3b and the second inner magnetic yoke 16 interfacing with the left and right second front cores 5a, 5b. have. Since the magnetic flux indicated by the solid arrow is recirculated through the mold 2 as in EP2633928B1, the electromagnetic braking device shown is only capable of generating a magnetic field that causes the left and right magnetic fields to have opposite directions. This applies regardless of the controllability of the magnetic coils 4a, 4b, 6a, 6b.

The present invention proposes a solution for improving the controllability of the magnetic braking field. 5 shows a thin slab casting machine having a flow rate control device 1 comprising an external yoke 7 as well as independently controllable left and right magnetic coils 4 and 6 on each side of the mold, according to an embodiment of the present invention. It is a schematic plan view. The left control interface 14a controls the excitation of the magnetic coils 4a, 6a corresponding to the left first and second front cores 3a, 5a. Preferably, the two coils are controlled in a cooperative manner in the sense described above. The right control interface 14b is arranged to energize the corresponding coil on the right side of the mold 2 . This flow rate control device 1 allows independent control of the magnetic field passing through different lateral positions of the mold 2 . The magnetic flux can circulate not through the mold 2 but through the outer loop with the outer yoke 7 . Regarding the general characteristics of the flow rate control device 1 according to the invention, reference is made to the above description of the electromagnetic braking device shown in FIGS. 1 to 4 .

In a variant of the embodiment shown in FIG. 5 , the first and second level cores 8 and 9 may also be divided into left first, right first, left second, and right second level cores. Then, the first left level core will interface with the first left anterior core and the like.

The support structure for the flow rate control device 1 is not explicitly shown in FIG. 5 . The flow rate control device 1 is preferably supported so that it can move independently of the mold 2 . Although the mold 2 can be mounted on a vibrating table, the flow rate control device 1 is preferably mounted on a support structure other than the vibrating table. In this way, since the vibration table can support a lighter load, its design can be simplified.

6 is a schematic diagram of the arrangement of flux-forming elements arranged on the proximal parts 5.1, 6.1 of the front cores 5, 6 of the flow rate control device 1 in a thin slab casting machine. A filled rectangle corresponds to a portion extending relatively closer to the mold 2 , and an empty rectangle corresponds to an end relatively farther from the mold 2 . Since the front cores 5 and 6, which may be made of mild steel, iron or other ferromagnetic material, have a much higher permeability than air, the magnetic flux will prefer a shorter air gap and be concentrated there. Therefore, the local magnetic field will be relatively stronger in the short air gap than in the long air gap, and thus the magnetic flux passing through the mold 2 will be distributed with higher flexibility. This flux distribution effect can be even more pronounced if the front core opposite the mold 2 has a symmetrical flux-forming element.

The configuration of the flux-forming element can be adapted to the expected flow pattern taking into account the internal geometry of the mold 2 , the characteristics of the SEN 13 , the casting speed, and the like, so that an appropriate braking action is achieved. In some embodiments, flux-formed elements can be reconstructed after deployment to become useful in other casting processes or to incorporate later insights into a given casting process. Reconfigurability is ensured if the flux-forming element is provided as a plurality of freely positionable magnetic protrusions 17 of the type shown in FIG. 7A . The protrusions 17 may be rods of iron or other ferromagnetic material that releasably fit into the recesses of the respective front cores. Reconstitution of the flux-forming element is preferably carried out between successive continuous casting batches.

In the example shown in FIG. 6 , the flux-shaping element will make the magnetic flux relatively stronger in the lower part except for the central part. In a further example shown in FIG. 7b , the flux-forming elements are arranged in a roughly bowl-like shape corresponding to positions on the mold 2 where stronger braking is expected. The width of each of FIGS. 6 and 7b corresponds approximately to the overall width of the mold 2 . The height may correspond to the upper part of the mold 2 as shown in the perspective views of FIGS. 1 and 2 .

It is recalled that, in accordance with one embodiment of the present invention, the left and right sides of each configuration shown preferably belong to respective left and right first (or second) front cores with associated magnetic coils. This achieves dynamic left/right controllability in addition to the option to reconfigure the flux forming elements between casting batches. In other embodiments with a higher number of magnetic coils, the lateral resolution of the controllability may be much finer. The patterns shown in FIGS. 6 and 7B are mirror symmetric with respect to the left/right direction, but it is also possible to use asymmetric patterns. The asymmetric braking force distribution due to this pattern may be beneficial in stabilizing the asymmetric casting jet from the SEN 13 .

8 shows a thin slab casting machine comprising independently controllable left and right magnetic coils 4a, 4b, 6a, 6b and an outer yoke 7 on each side of a mold 2, according to an embodiment of the present invention. It is a schematic plan view. A processor 18, left and right control interfaces 14a, 14b for energizing the magnetic coil, and left and right sensors 19a, 19b for detecting various flow parameters are further provided. Flow parameters may include temperature distribution or temperature gradient within mold 2 , meniscus height profile, meniscus velocity, meniscus height variation and/or other meniscus properties. The control interfaces 14a, 14b may be connected to a thyristor power converter, such as a converter in Applicants' DCS family, or may be realized as a thyristor power converter.

Local temperature can be sensed using placement of optical fibers using the method and apparatus disclosed in WO2017032488A1; In particular, please refer to FIGS. 1A, 1B, 1C, 1D and 2 among them. 9 of the present invention is a perspective view of the upper part of the casting mold 2 and the SEN 13 . On the wall of the mold 2 is a sensor array comprising a plurality of optical fibers (dotted lines) extending horizontally to the lateral openings, these fibers making it possible to detect temperature distributions or temperature gradients with high spatial resolution. The resulting sensor data can reveal coagulation anomalies and can also capture meniscus shape in detail to predict meniscus flow rates. As an alternative to FIG. 9 , a vertically arranged optical fiber may be used. The fully decentralized measuring system easily captures the flow velocity and fluctuations on the left and right sides of the SEN 13, and can be easily connected to the left/right independent flow rate control device 1 of the kind described above to manage the flow asymmetry. A high-resolution measurement of the temperature in the region close to the meniscus provides sufficient information to independently control the left and right flow rates. A possible alternative control method is based on a divided set of molded level sensors with separate information about the level and fluctuations from the left and right.

10 shows the SEN 13 and the resulting inlet velocity distribution v(x). The lower part of the figure is a cross-sectional side view of the SEN 13 embodied as a two-channel fishtail-shaped nozzle. In the upper part of FIG. 10 there is a cross-sectional view taken along line B-B, in which it can be seen that the SEN 13 has a flat cross-section substantially aligned with the lateral direction of the mold 2 . The mold-level sensor may enable the velocity distribution v(x) and the meniscus height h to be tracked, so that the flow rate control device 1 controls to apply a braking magnetic field suitable to stabilize the flow. can be The magnetic field stabilizes the flow of the molten metal and guides the momentum towards the meniscus into a double-roll flow pattern while minimizing meniscus fluctuations and providing a suitable shape to help control the meniscus local flow rate. can be configured. In one example, in the case of a 100×1400 mm mold and a skew inlet velocity condition involving ±50% velocity fluctuation, the left and right magnitudes of the applied magnetic field are such that the flow velocity at ±440 mm from the lateral center of the mold 2 is equal. It should vary by about 23%. When this magnetic field is applied, the meniscus flow asymmetry is substantially stabilized and the flow rate peak is attenuated.

Returning to the description of Fig. 8, the inventors have found that automatic meniscus flow rate and asymmetry control can be set using the left/right independent flow rate control device 1 in combination with an on-line flow measurement sensor such as the mold-level sensor described above. realized that there is The closed control loop may be realized in the processor 18 provided as an industrially suitable computer environment for robust and continuous operation. The control loop may, for example, execute a PID algorithm. As the processor 18, an ABB Ability™ Optimold Monitor commercially available by the present applicant may be selected.

When the flow rate of the meniscus in the mold is accurately predicted, the closed-loop control system controls interface 14a of the flow rate control device 1 to apply a variable braking magnetic field or electromagnetic field to counteract the meniscus velocity that is too low or too high. , 14b). the left control interface 14a controls the excitation of both the left first magnetic coil 4a and the left second magnetic coil 6a; It is understood that the right control interface 14b controls the excitation of both the right first magnetic coil 4b and the right second magnetic coil 6b. In the same way, the control loop cooperates with the flow rate control device 1 to mitigate the flow pattern asymmetry. For example, a higher flow velocity in one lateral half of the mold 2 may be suppressed by a locally enhanced DC (ie, non-oscillating) magnetic field. Control may be made on data from an electromagnetic level sensor, and high frequency feedback may be used to obtain detailed level and fluctuation information at the probing location. This makes it possible to control the meniscus speed and control the stability of the meniscus level in the upper part of the mold 2 .

In one embodiment, the control loop has two parts, the first part is the determination of the EMBR current based on process inputs such as casting speed, SEN geometry, SEN depth, steel grade, mold dimensions and similar process characteristics. Decisions may depend in part on magnetohydrodynamic simulations and/or recorded empirical data. The second part is the dynamic control of the EMBR. The meniscus level sensors 19 located on the left and right sides of the mold 2 measure the meniscus level and meniscus fluctuations, and the transient values can be taken as inputs for realizing dynamic control of the EMBR left/right current. . Dynamic control may include iterative positive and negative adjustments of the initially obtained EMBR current values based on process inputs.

In a further embodiment, the processor 18 coupled to the control interface 14 is configured to control the magnetic coil based on a numerical simulation of transient flow dynamics within the mold.

In the above, aspects of the present invention have been mainly described with reference to several examples. However, as will be readily understood by those skilled in the art, other embodiments other than those described above may likewise exist within the scope of the invention as defined by the claims.

1: device, flow control device, electromagnetic braking device
2: mold
3: first anterior core
3.1: proximal portion of the first anterior core
4: Coil associated with the first anterior core
5: second anterior core
5.1: proximal portion of the second anterior core
6: Coil associated with the second anterior core
7: Outer yoke
8: first level core
9: 2nd level core
10: electrical terminal
11: first refrigerant channel
12: second refrigerant channel
13: immersion nozzle
14: control interface
15: first inner yoke
16: second inner yoke
17: magnetic protrusion
18: processor
19: sensor

Claims (19)

A device (1) for controlling the flow rate in a mold (2) for continuous casting of metal,
at least two first front cores (3) having an associated first magnetic coil (4) disposed on one side of the mold;
at least two second front cores (5) having an associated second magnetic coil (6) disposed on opposite sides of the mold and substantially aligned with said first front core;
an outer magnetic loop (7, 8, 9) connecting the second front core to the first front core so that one-way magnetic flux can pass through the mold from the first front core to the second front core and vice versa; and
A device comprising a control interface (14) enabling independent control of two subsets of a first magnetic coil,
A device characterized in that the front core is provided with a reconfigurable flux-forming element for allowing a spatially non-uniform magnetic flux to pass through the mold. 2. The apparatus of claim 1, wherein the control interface enables independent control of the two subsets of the second magnetic coil. The apparatus of claim 1 or 2, wherein the subsets of the first or second magnetic coils are arranged differently relative to the lateral direction of the mold. 3. The apparatus of claim 1 or 2, wherein each subset of the first or second magnetic coils comprises one or more magnetic coils. 3. The device of claim 1 or 2, wherein the control interface is configured to cooperatively control a magnetic coil associated with the aligned pair of anterior cores. Device according to claim 1 or 2, wherein the control interface comprises electrical terminals (10) for energizing each subset of magnetic coils. Device according to claim 1 or 2, wherein the control interface comprises a processor (18). 8. The method of claim 7, further comprising one or more sensors (19), wherein the processor of the control interface comprises:
temperature distribution within the mold and/or
Meniscus height profile, meniscus velocity, meniscus height variation, or other meniscus characteristic.
an apparatus configured to control the magnetic coil based on sensor data from the sensor. 8. The apparatus of claim 7, wherein the processor of the control interface is configured to process sensor data having a spatial resolution for the lateral direction of the mold. 8. The apparatus of claim 7, wherein the processor of the control interface is configured to control the magnetic coil based on a numerical simulation of transient flow dynamics within the mold. The apparatus of claim 1, wherein the reconfigurable flux-shaping element comprises a plurality of freely positionable magnetic protrusions (17). 12. The method of any one of claims 1, 2 and 11, wherein the outer magnetic loop comprises:
first and second level cores (8, 9) arranged to interface with the first and second front cores, respectively; and
A device comprising an external yoke (7). 13. The apparatus of claim 12, wherein the level core is retractable from the mold. 12. The device of any one of claims 1, 2 and 11, further comprising a support structure that allows the device to move independently of the mold. 15. The device of claim 14, wherein no part of the device is supported by the vibrating table. It is a system for continuous casting of metal,
mold (2);
metal source 13; and
12. A system comprising the device of any one of claims 1, 2 and 11. 17. The system of claim 16, which is a thin slab caster. delete delete

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