Method for heating a steel-intermediate strip in the production of a steel-flat strip

Abstract

The invention relates to a method for heating, in particular reheating, an intermediate strip (2) during the production of flat strips, in which the intermediate strip (2) is heated by means of an induction module head (12) of an induction module (10) of an induction furnace (1), in particular of a rolling plant, preferably of a steel strip production plant, and mechanically positioning the induction module head (12) in accordance with at least one current parameter of the intermediate strip (2) at / in the induction furnace (1).

Description

[0001] The present invention relates to a method for heating, in particular reheating, an intermediate strip during the production of flat strip. Furthermore, the present invention relates to a system control for an induction furnace, a rolling mill, or a steel strip production system, in particular for the production of endless strip. Furthermore, the present invention relates to an induction furnace, a rolling mill, or a steel strip production system, in particular for the production of endless strip.

[0002] In a steel strip production plant, for example, for endless strip production (ESP), an induction furnace is used in the rolling mill of the steel strip production plant for reheating a (steel) intermediate strip of a (steel) flat strip to be formed using a casting and rolling method. This induction furnace is located, for example, between a high reduction mill (HRM) having, for example, two to four, and in particular three, rolling stands and a finishing mill (FM) having, for example, four to seven, and in particular five, rolling stands.

[0003] In addition to numerous other influencing factors, the quality of the finished flat strip depends on the heating or reheating of the intermediate strip in the induction furnace. Particularly for thin intermediate strips, the so-called transverse-field induction module (Transversal Flux) of the induction furnace has emerged as an efficient and therefore suitable solution for rolling mills in steel strip production plants. A rolling mill can comprise several rolling mills, similar to the above.

[0004] Furthermore, the quality of the finished flat strip depends on a uniform temperature distribution of the intermediate strip, particularly at the longitudinal end of the induction furnace, which is located behind the strip in the production direction. The more uniform the temperature distribution along the surface of the intermediate strip or along its transverse cross-section, the better the quality of the finished flat strip. The transverse direction is, of course, perpendicular to the two strip edges of the intermediate strip. The present invention is based on the objective of ensuring correct heating, and in particular correct reheating, of the intermediate strip during flat strip production.

[0005] EP 2 287 345 A1 teaches a method for controlling and / or regulating an induction furnace for a rolling mill, wherein the electrical actuation of the induction coils of the induction furnace is described.

[0006] JP S62013526A discloses a method for regulating the temperature of an induction-heated furnace for heating slabs using computer-based regulation.

[0007] JP 2007237240A discloses mechanical positioning of an induction coil.

[0008] The object of the present invention is achieved by a method for heating, in particular reheating, an intermediate strip during the production of flat strip by means of a system control for an induction furnace, a rolling mill, or a steel strip production plant, in particular for continuous strip production, and by means of an induction furnace, a rolling mill, or a steel strip production plant, in particular for continuous strip production. Advantageous developments, additional features, and / or advantages of the invention are apparent from the dependent claims and the following description.

[0009] Transverse field induction modules of induction furnaces, such as rolling mills for steel strip production plants, are typically installed and controlled in pairs in order to configure the power input into the center strip as uniformly as possible.

[0010] The first strip edge (edge region) can be heated via the closed end regions of the first transverse field induction module's induction module head, and the second strip edge (edge region) can be heated via the closed end regions of the second transverse field induction module's induction module head. This applies similarly to the open central regions of the transverse field induction modules; that is, the open central region of the induction module head of the first transverse field induction module is positioned opposite the open central region of the induction module head of the second transverse field induction module relative to the centerline of the induction furnace. See also Figures 3 to 7 (closed end regions: 13, open central region: 14).

[0011] In the context of studies on the quality of the finished flat strip, it has been found that at the longitudinal end of the induction furnace, which is located in the production direction and is located at the rear, the symmetrical temperature distribution of the intermediate strip ( Figure 2 ) represents a good compromise as a precursor to the currently practically unadjustable uniform temperature distribution in the operating intermediate belt (such a substantially uniform temperature distribution at the belt edges is achieved by Figure 1 The temperature distribution in FIG is represented by the solid line, wherein only a single induction module head is active here. )

[0012] In-depth research has revealed that due to the mechanical positioning of the induction module head relative to the induction furnace centerline, the actual positioning of the induction module head on the intermediate belt running through the rolling mill often deviates from the intended positioning. This is the case when the intermediate belt centerline does not coincide (parallel) with the induction furnace centerline. Contrary to previous assumptions, it has been shown that such deviations in both transverse directions, parallel and angular, are the rule, not the exception.

[0013] Therefore, it is important that the induction modules are correctly positioned relative to the intermediate strip in order to achieve a uniform temperature distribution of the intermediate strip along its surface in a transverse direction, for example, as a transverse line, i.e., also across its cross section. In the method according to the invention, the intermediate strip is heated by an induction module head of an induction furnace, in particular a rolling mill, preferably a steel strip production plant, in particular for continuous strip production, wherein the induction module head is mechanically positioned according to at least one current, i.e., actual, parameter of the intermediate strip in / within the induction furnace. Of course, at least one further parameter may be used, if necessary, to position the induction module head.

[0014] The induction module heads of the induction furnace are positioned according to the at least one parameter of the intermediate zone such that, at at least one location in / at the induction furnace, a temporally symmetrical thermal energy distribution (e.g., temperature distribution) of the operating intermediate zone occurs transversely to the intermediate zone centerline. In other words, the thermal energy distribution of the operating intermediate zone is observed at this at least one location. The thermal energy distribution or the symmetry of the thermal energy distribution is not dependent on a deviation of the intermediate zone centerline from the induction furnace centerline.

[0015] Based on the at least one parameter of the intermediate zone, the induction module heads can be positioned in a chronological order at at least one location in / at the induction furnace to attempt or intentionally achieve a temporary symmetry in the thermal energy distribution of the intermediate zone, or to further symmetrize this temporary symmetry. Alternatively or additionally, an attempt or intentionally can be made to homogenize the thermal energy distribution of the intermediate zone in a transverse direction at and / or within the intermediate zone. Alternatively or additionally, an attempt or intentionally can be made to adapt the thermal energy of the intermediate zone edges to the thermal energy of the intermediate zone centerline.

[0016] The parameters of the intermediate strip can reflect essentially current (actual) conclusions about the current (actual) intermediate strip at / in the induction furnace and / or at / in the rolling mill. Furthermore, the parameters of the intermediate strip cannot represent merely general conclusions about the induction furnace and / or the rolling mill itself. That is, for example, the parameters of the intermediate strip do not reflect merely local or global conclusions about the induction furnace and / or the rolling mill itself. These parameters can represent current conclusions about the interaction of the intermediate strip with the induction furnace and / or the rolling mill itself. Furthermore, these parameters can represent current conclusions about the current state of the intermediate strip at / in the induction furnace and / or about the intermediate strip itself.

[0017] The parameters of the intermediate zone cannot reflect merely geometrical conclusions about the induction furnace and / or the rolling mill itself, or the lateral limitations of the intermediate zone within the induction furnace and / or the rolling mill itself. This also applies to other identifications of the intermediate zone that are essentially solely determined by the induction furnace and / or the rolling mill itself. The parameters of the intermediate zone can reflect the geometric position of the intermediate zone within the rolling mill and / or the induction furnace and / or the distribution of heat energy of the intermediate zone in / within the rolling mill and / or the induction furnace along the transverse direction of the intermediate zone.

[0018] It is crucial that the distance between the induction modules and the strip edges of the intermediate strip is precisely adjusted to achieve a symmetrical and, if necessary, uniform (similar values and / or no discontinuities (high gradients, bends)) heat energy distribution of the intermediate strip over its surface, across its width (considered as a width line) or across its cross section. The actual positioning of the induction module heads relative to the strip edge or edges of the intermediate strip is not known with sufficient precision in the prior art. The subsequent measurement locations for the intermediate strip are located spatially significantly upstream of the induction furnace and / or rolling mill and / or spatially significantly downstream of the induction furnace and / or rolling mill.

[0019] The parameters of the intermediate belt can reflect the intermediate belt centerline in the induction furnace. Other values, particularly other current measured values, can be incorporated into the parameters of the intermediate belt. Furthermore, the current thermal energy distribution in the intermediate belt can be incorporated into the parameters of the intermediate belt. Furthermore, the parameters of the intermediate belt can essentially represent only the intermediate belt centerline. Furthermore, the intermediate belt centerline can be detected by a centerline detection mechanism. Such a centerline detection mechanism can operate, for example, using at least one side guide roller, a centerline measurement mechanism, an edge measurement mechanism, an image processing mechanism, a vision mechanism / system, and the like.

[0020] The center line of the intermediate belt in an induction furnace can be determined from the current positioning of exactly / at least one, exactly / at least two, or exactly / at least four side guide rollers on the intermediate belt. Using the positioning of a single side guide roller, together with the known width of the intermediate belt in the transverse direction, a point / segment of the center line of the intermediate belt in the induction furnace can be determined at a position of the side guide roller. Using (at least) two side guide rollers arranged offset in the longitudinal direction of the induction furnace, the center line in the induction furnace can thus be determined.

[0021] This can be extended to side guide roller pairs, wherein, by means of one side guide roller pair, a point / section of the center line of the center strip in the induction furnace can be determined at one position of the side guide rollers without knowing the width of the center strip. By means of (at least) two side guide roller pairs arranged offset in the longitudinal direction of the induction furnace, the center line in the induction furnace can thus be determined without knowing the width of the center strip.

[0022] The current position of the lateral guide rollers can be determined / obtained from the force control of the lateral guide rollers. The current position of the lateral guide rollers, determined by force control, is therefore used to identify the centerline of the intermediate strip. The centerline of the intermediate strip detected by the lateral guide rollers is communicated to the system control (automatic control) of the induction furnace. The current position of the lateral guide rollers can be used to determine the current parallel and / or angular offset of the centerline of the intermediate strip relative to the centerline of the induction furnace.

[0023] The parameters of the intermediate zone can reflect the thermal energy distribution of the intermediate zone within the induction furnace. Other values, in particular other current measured values, can be incorporated into the parameters of the intermediate zone. Furthermore, the current center line of the intermediate zone can be incorporated into the parameters of the intermediate zone. Furthermore, the parameters of the intermediate zone can essentially represent only the thermal energy distribution of the intermediate zone. Furthermore, the thermal energy distribution of the intermediate zone can be detected by a temperature determination device, in particular a temperature scanner.

[0024] The current heat energy distribution of the central zone can be determined in the transverse direction. A current trend line can then be determined from the heat energy distribution, which reflects the current symmetry of the heat energy distribution of the central zone in the transverse direction. Based on this current trend line, the induction module heads of the induction furnace can be positioned such that the current symmetry of the heat energy distribution of the central zone in the transverse direction is symmetrical, or at least not asymmetrical.

[0025] For example, a trend line older in time is compared with the current trend line or the current trend line is compared with an ideal trend line so that the current trend line should show at least a uniform, symmetrical thermal energy distribution or an improved symmetry of the thermal energy distribution. The thermal energy distribution of the intermediate zone can be determined, for example, by a temperature determination device, in particular a temperature scanner, as the temperature distribution of the intermediate zone.

[0026] In one embodiment, the current incoming heat energy distribution of the intermediate zone in the transverse direction can be determined before the actual induction furnace (at the beginning / inside the induction furnace) and / or in the preceding induction furnace (in the front half of the induction furnace). The required electrical power of the induction furnace, the required electrical power distribution within the induction furnace, and / or the required position of the induction module head in the transverse direction can be determined from this heat energy distribution. Furthermore, the induction module head can preferably be initially positioned in anticipation of any asymmetry in the temperature distribution of the incoming intermediate zone into the induction furnace. The method hereby projects a certain time into the future, and if necessary, the induction module head is positioned accordingly, with modifications to the method being necessary.

[0027] In one embodiment, the current heat energy distribution of the intermediate strip in the transverse direction, in the subsequent induction furnace (the rear half of the induction furnace) and / or after the actual induction furnace (at / at the end of the induction furnace), can be determined. From this heat energy distribution, a current trend line can be determined, which reflects the current symmetry of the heat energy distribution of the intermediate strip in the transverse direction. Based on this trend line, the induction module heads can then be positioned to compensate for any asymmetry in the temperature distribution of the exiting intermediate strip. This can take into account the current heat energy distribution of the intermediate strip in the transverse direction. In other words, induction module heads positioned above / below the cooler strip edge are moved further toward this strip edge.

[0028] The method can be operated such that the current trend line of the current thermal energy distribution in the intermediate zone approaches a desired (good to essentially optimal) trend line (target trend line). To this end, the relevant induction module heads located above / below the intermediate zone are positioned accordingly. The relevant trend lines can be linear, nonlinear, composite trend lines, etc. The method can be designed as a control method or a regulation method (closed-loop control). The induction modules can be designed as transverse field induction modules. This also naturally means that the induction module heads are designed as transverse field induction modules.

[0029] The system control system according to the present invention is designed such that the method according to the present invention can be implemented and / or carried out by the system control system. The system control system comprises a system controller and the necessary connections. The induction furnace according to the present invention, the rolling mill according to the present invention, or the steel strip production plant according to the present invention comprises a system control system according to the present invention. Furthermore, the method according to the present invention can be implemented and / or carried out by the induction furnace according to the present invention, the rolling mill according to the present invention, or the steel strip production plant according to the present invention.

[0030] The invention is explained in detail below with reference to exemplary embodiments and schematic, not-to-scale drawings. Sections, elements, components, units, assemblies, and / or diagrams having the same, single meaning, or similar design and / or function are denoted by the same reference numerals in the description of the figures (see below), in the list of reference numerals, in the claims, and in the illustrated figures (figures). With respect to exemplary embodiments or assemblies, diagrams, units, components, elements, or sections thereof, possible, non-explained alternatives, static and / or dynamic reversals, combinations, etc., not shown in the description of the invention (see above), or in the drawings, can also be seen from the list of reference numerals and / or in the description of the figures.

[0031] In the present invention, a feature (section, element, component, unit, assembly, function, parameter, etc.) can be positive, i.e., present, or negative, i.e., absent. In this technical specification (description (description of the invention (see above), description of the drawings (see below), list of reference numerals, claims, drawings), a negative feature is not explicitly explained as a feature when its absence is not taken into account according to the present invention. In other words, the invention that is actually completed and not provided by the prior art is the omission of this feature.

[0032] The features of this technical specification can be used not only in the manner and / or method described, but also in other manners and / or methods (isolated, combined, substituted, supplemented, separate, omitted, etc.). In particular, it is possible to replace, supplement, or omit features in the claims and / or description based on a reference numeral in the description, list of reference numerals, claims, and / or drawings and the features assigned to these reference numerals, or vice versa. Furthermore, features in the claims can be explained and / or elaborated in this manner.

[0033] Features of the description can also be interpreted as optional features (in view of the (primarily mostly unknown) prior art); that is, each feature can be understood as an optional, arbitrary or preferred feature, that is, as a non-binding feature. Thus, a feature, including its surroundings, can be omitted from an exemplary embodiment, whereby this feature can then be applied to the generalized inventive concept. The absence of a feature (a negative feature) in an exemplary embodiment indicates that this feature may be optional with respect to the invention (for a person skilled in the art). Furthermore, the generic term for a feature can also be read in conjunction with the generic term for this feature (possibly further hierarchically divided into subgenerics, etc.), thereby allowing, for example, generalization of the features while taking into account identical effects and / or equivalence.

[0034] In the merely exemplary and schematic illustrations of the accompanying drawings:

[0035] Figure 1 and 2 In each case, a single transverse field induction module ( Figure 1 ) and through a plurality of paired mounted transverse field-induction modules ( Figure 2 ) the temperature distribution in the steel strip manufacturing plant after the intermediate strip is reheated,

[0036] 3, 4 and 8 show the prior art in a two-dimensional, greatly simplified top view, wherein the induction module heads of the induction modules are related to the center line of the rolling mill and the center line of the intermediate belt is parallel (FIG. 4) or at an angle (FIG. Figure 5 ) deviates from the center line of the rolling mill,

[0037] Figure 5 and 7 An example of a first embodiment of the invention is shown in a two-dimensional, greatly simplified top view, wherein the induction module head is related to the center line of the middle strip and the middle strip center line is parallel ( Figure 5 ) or at an angle ( Figure 7 ) deviates from the mill centerline, and

[0038] Figure 8 、 9 10 show a second embodiment of the present invention, wherein the trend line of the asymmetric temperature distribution through the middle zone ( Figure 8 ) and the corresponding positioning of the sensing module head ( Figure 10 ) to control or adjust the trend line of the symmetrical temperature distribution in the middle zone ( Figure 9 ).

[0039] In the following, two embodiments (first embodiment: Figure 5 and 7 , the second implementation method: Figures 8 to 10 Although the present invention has been described and illustrated in more detail by way of preferred embodiments, the present invention is not limited to the disclosed embodiments but has basic characteristics.

[0040] Other variants can be derived therefrom and / or from the above description (invention description) without departing from the scope of protection of the present invention. The present invention can be used generally in induction furnaces, in particular in the field of steel production, preferably for producing flat strip (see above). The figures show only those spatial sections of the subject matter of the present invention that are necessary for understanding the invention.

[0041] The following explanation of the invention with reference to the drawings relates to the longitudinal direction Lr and the transverse direction Qr. The longitudinal direction Lr corresponds to the main extension direction of the intermediate strip 2 (and of the finished flat strip), of the induction furnace 1, of the rolling mill, and, if applicable, of the strip production plant, while the transverse direction Qr is perpendicular to the longitudinal direction Lr and lies in the horizontal plane of the intermediate strip 2 (and of the finished flat strip).

[0042] Induction furnace center line M I Here, the straight line represents the center line M of the induction furnace 1 or of the rolling mill, parallel to the longitudinal direction Lr.Z Here, the straight line represents the center line M of the intermediate strip 2, in particular in an induction furnace 1 or in a rolling mill, mainly parallel to the longitudinal direction Lr. Z About Induction Furnace Center Line M I Run essentially parallel, offset or at an angle (small angle).

[0043] For design reasons, see also Figures 3 and 4, in the induction furnace 1, a local overheating of the (first) strip edge 22 (edge region 22) of the intermediate strip 2 is generated on one side by the induction module head 12 (coil current I) of the single transverse field induction module 10 ( Figure 1 , overheating on the left). This overheating is caused by eddy currents caused by the open central region 14 of the induction module 10. The overheating of the first strip edge 22 is clearly independent of the position of the induction module head 12 relative to the center strip 2 due to the geometric expansion of the induction module head 12 in the transverse direction Qr, since the induction module head 12 protrudes beyond the first strip edge 22.

[0044] See also the temperature distribution T Z1 (dotted line), T Z2 (solid line), T Z3 (dashed lines), which show the dependence of the temperature of the intermediate strip 2 on the position of the induction module head 12 along the transverse direction Qr on the intermediate strip 2. Here, the temperature distribution T Z1 represents the induction module head 12 that projects beyond the second strip edge 22 (edge region 22) opposite the first strip edge 22 (approximately +20 mm for a width of the intermediate strip 2 in the transverse direction Qr of approximately 1,200 mm). Z2 represents the induction module head 12 in the correct position with respect to the second strip edge 22. And the temperature distribution T Z3 This represents the induction module head 12 not extending sufficiently to the second belt edge 22 (approximately -20 mm in the above example).

[0045] That is, with respect to the first edge 22 ( Figure 1 , open central section 14) along the transverse direction Qr opposite the second edge 22 is either essentially intentionally heated correctly (for induction modules 10 installed in pairs; see Figure 1 , solid line T Z2 If the induction module head 12 does not extend all the way to this strip edge 22, then insufficient heating is obtained (see Figure 1 Right, dotted line T Z3If the induction module head 12 extends beyond this strip edge 22, an overheating similar to the overheating of the open central region 14 is obtained (see Figure 1 Right, dotted line T Z1 ).

[0046] To counteract this and to obtain in the ideal case a symmetrical temperature distribution T of the intermediate zone 2 Z (Similar to the geothermal energy distribution T Z )(See Figure 2 ), the sensing modules 10 are installed in pairs (see FIG. 3 to FIG. Figure 7 ). As a result, each strip edge 22 of the intermediate strip 2 passes not only through the closed end regions 13 of two directly adjacent induction module heads 12 of two induction modules 10 or a plurality of such pairs (see FIG. 3 : five such pairs) but also through the open central region 14 thereof. As a result, the strip edges 22 of the intermediate strip 2 are heated substantially identically (see FIG. Figure 2 In this case, the input of electrical power into the intermediate strip 2 by means of the inductive module heads 12 is essentially symmetrical.

[0047] The distance of the induction module head 12 from the intermediate strip 2 , ie from its two strip edges 22 , 22 , decisively influences the temperature distribution T of the intermediate strip 2 across its width. Z The temperature distribution is shown as a variation line along the transverse direction Qr. Figure 1 and 2 Shown in. Figure 1 The figure shows how the distance of the induction module 10 from the two strip edges 22, 22 of the central strip 2 influences the power input into the central strip 2 (vertical axis: temperature distribution T in the form of a line power density, for example) within the width of the central strip 2 in the transverse direction Qr (right axis: left strip edge 22 to the furnace centerline M1 to the right strip edge 22). Z , with description of temperature, etc.).

[0048] Therefore, the further the induction module head 12 is from the outer strip edge 22 (see the upper induction module head 12 in FIG. 4 ), the lower the power input and the subsequent temperature there will also be (see the temperature distribution T of the middle strip 2 in FIG. 4 ). Z ). In order to Z To achieve uniform heating of the two strip edges 22, 22, the induction modules 10 are always installed in pairs. Figure 2 right, Figure 2 The results of the electrical power input are shown for a plurality of induction modules 10 connected in pairs.

[0049] Here, the first induction module head 12 heats the first strip edge 22 with its open central region 14 and heats the second strip edge 22 lying opposite thereto in the transverse direction Qr with its closed end region 13; see, for example, the leftmost induction module head 12 in FIG3 . Antiparallel to this, the second induction module head 12 heats the second strip edge 22 with its open central region 14 and heats the first strip edge 22 lying opposite thereto in the transverse direction Qr with its closed end region 13; see, for example, the induction module head 12 to the right of the leftmost induction module head 12 in FIG3 .

[0050] The mechanical positioning of the individual transverse field induction modules 10 is in the prior art (see FIG. 3 ) relative to the induction furnace centerline M of the rolling mill. I Absolutely, at the center line M of the induction furnace I In the example mentioned at the beginning, the intermediate strip 2 is carried out between the high-reduction mill and the finishing mill. Z Not always on the center line M of the induction furnace I See Figure 4. However, in the induction furnace, the center line M I On this basis, the lateral field sensing module 10 and its sensing module head 12 are positioned in the prior art.

[0051] If the median line M Z Deviation from the center line M of the induction furnace I 4 (but the induction module head 12 relates to the center line of the induction furnace), then the asymmetric temperature distribution T discussed above appears at the outlet of the induction furnace 1 at the edge 22 of the intermediate belt 2. Z . Asymmetric temperature distribution T Z (The far right of Figure 4) This may then lead to product quality issues and process stability problems.

[0052] This problem can be solved by at least one of the following measures: - Detecting the actual or current median strip centerline M Z , and is used for the horizontal positioning of the sensing module 10 or its sensing module head 12 (centerline detection). By positioning the side guide rollers 30 on the middle belt 2, for example by means of force adjustment, the current middle belt centerline M of the middle belt 2 can be identified. Z As a supplementary solution or alternative solution, the current middle belt center line M can also be detected by other suitable center line detection mechanisms (other mechanisms or devices at the middle belt 2, image processing mechanisms, visual mechanisms / systems). Z .

[0053] Next, the actual or current, in particular horizontal, center line M of the center line 2 isZ The device control mechanism is communicated to the device control mechanism (automatic control) of the induction furnace 1. The device control mechanism is based on the detected and communicated middle belt center line M Z Position each sensing module 10 or its sensing module head 12. Thus, it is possible to rely on the current middle belt center line M Z The sensing module 10 or its sensing module head 12 is positioned and thus even on the center line M of the middle strip 2 Z Deviation from the center line M of the rolling equipment I Symmetrical temperature distribution T Z (See Figure 5 far right).

[0054] This makes it possible, on the one hand, to detect deviations of the intermediate strip 2 in the transverse direction Qr (see Figure 5 , lateral direction - deviation) and the middle strip 2 relative to the middle strip center line M Z angular deviation (see Figure 7 , angular deviation) is compensated. — Figures 3 to 7 mainly show the intermediate zone 2 relative to the center line M of the induction furnace. I The running (arrow, with the middle line M Z ), the position of the induction module head 12 and the temperature distribution T of the intermediate zone 2 at the outlet of the induction furnace 1 Z (far right).

[0055] Figures 3 and 4 illustrate the prior art. First (Figure 3), the intermediate belt 2 is run in the center of an induction furnace 1, such as a rolling mill. The induction module head 12 is positioned symmetrically on the belt path of the intermediate belt 2 (fixed to the induction furnace). The current positioning (randomly) corresponds to the desired or previously calculated positioning, since the intermediate belt centerline M Z With induction furnace center line M I Coincident. This results in a symmetrical temperature distribution T Z (Figure 3, far right).

[0056] In FIG4 , the intermediate belt 2 does not run in the center of the induction furnace 1. The intermediate belt center line M Z The induction module head 12 is related to the center line M of the induction furnace. I , whereby the induction module head 12 is positioned asymmetrically on the middle belt 2. The previously calculated positioning does not correspond to the current positioning, because the middle belt center line M Z Different from the induction furnace center line M I Therefore, an asymmetric temperature distribution T occurs in the prior art. Z .

[0057] exist Figure 5In the embodiment, the middle belt 2 is also not running in the center of the induction furnace 1. However, the middle belt center line M Z The current position of the side guide rollers 30 on the intermediate belt 2 is known. In other words, the current position of the side guide rollers 30 can be used to determine the current intermediate belt center line M. Z .

[0058] The sensing module head 12 may now be related to the median strip center line M Z The induction module head 12 is now symmetrically positioned on the middle belt 2 and no longer symmetrically positioned on the induction furnace centerline M. I The calculated positioning corresponds to the current positioning, since the median line M is now Z This is crucial for the positioning of the induction module head 12 on the intermediate strip 2. This also results in a symmetrical temperature distribution T of the intermediate strip 2. Z ( Figure 5 far right).

[0059] In FIG6 (prior art), the intermediate belt 2 does not run in the center of the induction furnace 1, but runs at an angle relative thereto. Z The induction module head 12 is related to the induction furnace center line M I , whereby the induction module head 12 is positioned asymmetrically on the middle belt 2. The calculated positioning does not correspond to the current positioning, since the middle belt centerline M Z Different from the induction furnace center line M I As a result, an asymmetric temperature distribution T Z (Figure 6, far right).

[0060] exist Figure 7 In the example shown in FIG. 1 , the intermediate belt 2 is also not running in the center of the induction furnace 1 but is running at an angle relative thereto. Z The positioning of the side guide rollers 30 is known. The induction module head 12 may now be related to the middle belt center line M Z , and is positioned accordingly. The induction module head 12 is now positioned symmetrically on the middle belt 2. The calculated positioning corresponds to the current positioning, since the middle belt center line M is now Z This is crucial for the positioning of the induction module head 12 on the intermediate strip 2. This results in a symmetrical temperature distribution T of the intermediate strip 2. Z ( Figure 7 far right).

[0061] In addition, see Figures 8 to 10 As an alternative or in addition, at the beginning, in the center and / or at the end of the induction furnace 1 ( Figure 10) The current temperature distribution T of the intermediate strip 2 can be detected, for example, by a temperature determination device, in particular a temperature scanner 40 . Z Using this temperature distribution T Z , in order to position the induction module head 12 horizontally by means of a control method or a regulating method (closed loop control) and to improve the temperature distribution T as much as possible Z If the temperature distribution T on one side of the intermediate zone 2 is found Z If the temperature distribution T deviates from the standard, the induction module head 12 is positioned so that a temperature distribution T that is as symmetrical as possible and, if necessary, uniform is obtained. Z .

[0062] Figure 8 Such a middle strip 2 is shown with respect to the middle strip center line M. Z Asymmetrical, along the line (horizontal axis: 22 to M Z 22) Temperature distribution T on the surface of the intermediate belt 2 along the transverse direction Qz Z From this temperature distribution T Z In this case, a trend line Tr, in this case a linear trend line Tr, can be ascertained or calculated. The trend line Tr can be ascertained or calculated in many different ways.

[0063] A simple form is the temperature distribution T of the middle zone 2. Z The absolute minimum or maximum of the connecting lines can be connected. Furthermore, the average value of two such connecting lines, optionally weighted, can be used as trend line Tr. In this case, the region of the intermediate strip 2 that ends at the strip edge 22 can be given a special weighting. Of course, higher-order trend lines Tr, i.e., nonlinear trend lines Tr, for example, can also be used.

[0064] The horizontal orientation of the induction module head 12 is now changed by a control or regulation method in such a way that the trend line Tr comes as close as possible to a predetermined, substantially good to optimal solution, which is also represented by the trend line Tr ( Figure 9 ). In the present case, in the illustrated example of a linear trend line Tr, the slope of a substantially good to substantially optimal trend line Tr is zero (the trend line Tr is substantially parallel to the right axis). The current trend line Tr should be close to this slope and coincide with it as closely as possible.

[0065] For this purpose, it is preferred that only those induction module heads 12 that can be used to implement the trend line Tr be adjusted (positioned) horizontally. This is usually a maximum of half of all existing induction module heads 12, that is, those induction module heads whose closed end regions 13 are located above / below the cold strip edge 22. Of course, it is also possible to adjust these induction module heads 12 in pairs, for example, by the same amount, since a movement of the open central region 14 of the induction module head 12 has no significant effect on the temperature of the strip edge 22.

[0066] As in Figure 10 As shown in FIG, the temperature distribution T of the intermediate strip 2 along the transverse direction Qr before the induction furnace 1 Z (Thermal energy distribution T Z ) is determined, for example, by a temperature scanner 40 (on the left in FIG. 4 ). The signals of this temperature scanner 40 are used to determine, by means of a suitable model, the required electrical power of the induction modules 10 or the induction module heads 12 of the induction furnace 1, the required electrical power distribution on the induction modules 10 or their induction module heads 12 within the induction furnace 1, and the required position of the induction module heads 12 above / below the center strip 2 in the transverse direction Qr, in order to achieve the desired temperature within permissible limits and a symmetrical temperature distribution T Z .

[0067] In addition to the necessary (as symmetrically as possible and, if necessary, uniform) energy input into the intermediate strip 2, for example, for finish rolling the intermediate strip 2, it is thus possible to anticipate compensation for the asymmetrical temperature distribution of the intermediate strip 2 by the induction furnace 1 already after rolling the intermediate strip 2 and before heating the intermediate strip 2 in the induction furnace 1. This means that the relevant induction module heads 12 should initially be positioned in such a way that the incoming temperature distribution T of the intermediate strip 2 can be compensated. Z The positioning of the induction module head 12 can then of course be further varied by the method according to the invention in such a way that the resulting temperature distribution T of the intermediate strip 2 can be compensated additionally or primarily. Z The identified asymmetry.

[0068] The temperature distribution T of the intermediate belt 2 along the transverse direction Qr at the outlet or rear end of the induction furnace 1 is Z The determination can also usually be carried out by means of a temperature scanner 40 (in Figure 10 If the temperature distribution T is determined or measured as described above in such a measurement Zand, for example, calculate a non-horizontal trend line Tr, a correction can be performed. The correction relates in particular to the longitudinal sections of the intermediate belt 2 in the induction furnace 1 that follow in time, for the intermediate belt 2, due to the intermediate belt center line M Z Deviate from the center line M of the induction furnace I Compensation for asymmetrical temperature distribution caused by

[0069] This is like Figure 10 The process is as shown in FIG. 1 , in that the induction module heads 12 positioned on the cooler strip edge 22 continue to move in the direction of the cooler strip edge 22 (dotted arrows). Figure 8 and 9 As shown in FIG, this also results in an increased concentration of the magnetic field / eddy currents in the intermediate strip 2 on this side and thus in a higher strip edge temperature (see FIG. Figure 10 Temperature distribution T Z dashed line in the middle).

[0070] This can be done by control / regulation, wherein the induction module head 12 is moved so far that the determined temperature distribution T Z The temperature distribution T in the intermediate zone 2 is symmetrical again, for example, the trend line Tr becomes horizontal. Preferably, the calculation model for compensating for temperature asymmetry can precalculate the necessary movements of the induction module heads 12 and position the induction module heads 12 according to the calculated shifts, which leads to a more rapid achievement of a symmetrical temperature distribution T in the intermediate zone 2. Z .

[0071] In addition, taking into account the inlet temperature distribution T Z In the case of Figure 10 The dashed arrows in FIG and its complementary sensing module head 12 (in the pair of sensing modules 10 ) are indicated. Thus, the power requirement, temperature distribution T Z Essentially all requirements with regard to symmetrization and, if necessary, homogenization and compensation of temperature asymmetries are met and repeatedly specified as new target values for the control / regulation of the induction furnace 1 .

[0072] Furthermore, the temperature distribution T Z And also find out the trend line Tr at another position (at Figure 10 Thus, the next induction module head 12 after the temperature scanner 40 can be used to control / regulate the symmetrical temperature distribution T ZThe method can be operated both with the incoming temperature scanner 40 as the only temperature scanner 40 and with the outgoing temperature scanner 40 as the only temperature scanner 40. Of course, it is also possible to use two temperature scanners 40, 40. The temperature scanner 40 (in Figure 10 In brackets) can be used in all embodiments, but can also be omitted.

Claims

1. A method for heating, in particular reheating, an intermediate strip (2) during the production of a flat strip, wherein The intermediate strip (2) is heated by an induction module head (12) of an induction module (10) of an induction furnace (1), in particular of a rolling mill, preferably a steel strip production plant, characterized in that The induction module head (12) is mechanically positioned according to at least one current parameter of the intermediate belt (2) at / in the induction furnace (1) such that At least one position in / at the induction furnace (1) is formed at / in the intermediate zone (2) along a transverse direction (Qr) about a centerline (M) of the intermediate zone. Z ) The time-symmetrical heat energy distribution (T Z ).

2. The method according to any one of the preceding claims, characterized in that Attempting intentionally by positioning the induction module head (12) at at least one location in / at the induction furnace (1) in a chronological order according to at least one parameter of the intermediate zone (2): The heat energy distribution (T Z ) is obtained from the temporary symmetry of the thermal energy distribution (T Z ), or continue to make this temporary symmetry symmetrical, • The heat energy distribution (T Z ) homogenization, and / or · Make the heat energy of the edge (22) of the middle belt (2) and the center line (M Z )’s thermal energy.

3. The method according to any one of the preceding claims, characterized in that Parameters of the intermediate zone (2) reflects substantially current conclusions about the current intermediate zone (2) at / in the induction furnace (1) and / or at / in the rolling mill, and / or It does not represent merely general conclusions about the induction furnace (1) itself and / or the rolling mill itself.

4. The method according to any one of the preceding claims, characterized in that Parameters of the intermediate zone (2) - does not reflect merely geometrical conclusions about the induction furnace (1) itself and / or the rolling mill itself, The center line (M) of the intermediate zone (2) in the induction furnace (1) itself and / or in the rolling mill itself is not reflected. I ) or lateral restraints, reflecting the geometric position of the intermediate strip (2) within the rolling mill and / or induction furnace (1), and / or Reflects the heat energy distribution (T Z ).

5. The method according to any one of the preceding claims, characterized in that The parameters of the middle zone (2) reflect the middle zone center line (M Z ),in: Other values, in particular other current measured values, are entered into the parameters of the intermediate band (2), The current thermal energy distribution (T Z ) into the parameters of the intermediate band (2). The parameters of the middle zone (2) basically represent only the middle line of the middle zone (M Z ), and / or The median line of the median (M Z ) is detected by the center line detection mechanism.

6. The method according to any one of the preceding claims, characterized in that Determine the center line (M) of the middle belt in the induction furnace (1) from the current positioning of exactly / at least one, exactly / at least two or exactly / at least four side guide rollers (30) on the middle belt (2) Z ), The current positioning of the lateral guide roller (30) is known / obtained from the force regulation of the lateral guide roller (30), and / or The center line (M) of the intermediate belt is determined from the current position of the side guide rollers (30). Z ) relative to the center line of the induction furnace (M I )'s parallel and / or angular current offset.

7. The method according to any one of the preceding claims, characterized in that The parameters of the intermediate zone (2) reflect the heat energy distribution (T Z ),in: Other values, in particular other current measured values, are entered into the parameters of the intermediate band (2), Current median line (M Z ) into the parameters of the intermediate band (2), The parameters of the intermediate zone (2) basically represent only the thermal energy distribution (T Z ), and / or Detecting the thermal energy distribution (T Z ).

8. The method according to any one of the preceding claims, characterized in that Determine the current thermal energy distribution (T) of the intermediate strip (2) along the transverse direction (Qr) Z ),and From the thermal energy distribution (T Z ) to determine the current trend line (Tr), which reflects the thermal energy distribution (T) of the intermediate zone (2) along the transverse direction (Qr). Z ) of the current symmetry, where According to this current trend line (Tr), the induction module head (12) of the induction furnace (1) is positioned so that the heat energy distribution (T Z )'s current degree of symmetry is symmetrical or at least not asymmetrical.

9. The method according to any one of the preceding claims, characterized in that Determine the current heat energy distribution (T) entering the intermediate zone (2) in the transverse direction (Qr) before the actual induction furnace (1) and / or in the preceding induction furnace (1). Z ), and from this thermal energy distribution (T Z )middle The required electrical power of the induction furnace (1), the required electrical power distribution within the induction furnace (1) and / or the required position of the induction module head (12) in the transverse direction (Qr) are determined, wherein The induction module head (12) should preferably be positioned in such a manner that the temperature distribution (T Z ) into the induction furnace (1) to compensate for the asymmetry.

10. The method according to any one of the preceding claims, characterized in that Determine the current thermal energy distribution (T) of the intermediate zone (2) in the transverse direction (Qr) in the subsequent induction furnace (1) and / or after the actual induction furnace (1). Z ), where the thermal energy distribution (T Z )middle The current trend line (Tr) is determined, which reflects the thermal energy distribution (T Z ) and positions the induction module head (12) according to the trend line (Tr) so that the temperature distribution (T Z ) is compensated for the asymmetry of The current thermal energy distribution (T Z ).

11. The method according to any one of the preceding claims, characterized in that The method is run in such a way that the current thermal energy distribution (T Z )’s current trend line (Tr) is close to the desired trend line (Tr).

12. A plant control device for an induction furnace, a rolling mill or a steel strip production plant, in particular for continuous strip production, characterized in that The method according to one of the preceding claims can be carried out and / or executed by the system control.

13. An induction furnace (1), a rolling mill or a steel strip manufacturing plant, in particular for continuous strip production, characterized in that The induction furnace (1), rolling mill or steel strip manufacturing plant has an induction module head (12), wherein The induction furnace (1), rolling mill or steel strip production plant has a plant control according to the preceding claims and / or is capable of and / or implements a method according to any of the preceding claims via the induction furnace (1), rolling mill or steel strip production plant.

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