Determining the lateral offset of the metal strip based on the coil end face contour

Abstract

A rolling mill comprising a rolling stand (1) and a pay-off reel (2) arranged upstream thereof. A metal strip (4) forming a coil (3) is unwound from the reel (2) and fed from the stand (1). The strip (4) is rolled in the stand (1). A particular portion (i) of the strip (4) has a lateral offset (V) at a given distance from the stand (1). A control device (8) determines a particular manipulated variable (C) by evaluating the lateral offset (V) of an actuator (12) associated with the stand (1) and controls the actuator (12) according to this variable (C). Before unwinding the strip (4), the contour (K) of the end face (11) of the still wound coil (3) is recognized by the device (8). As a result, information of the lateral offset (V) of the portion (i) over the entire length of the strip (4) is available to the device (8) even before the strip (4) is fed to the stand (1). The device (8) uses the contour (K) to determine a particular lateral offset (V).

Description

[Technical field]

[0001] The invention is based on a method of operating a rolling mill having at least one rolling stand and an uncoiler arranged upstream of said rolling stand, comprising: - In the rolling mill, the coiled metal strip is uncoiled by an uncoiler, from where it is fed to a rolling stand, where it is rolled, a control device for the rolling stand, utilizing a respective lateral offset that each portion of the metal strip has at a predetermined distance upstream from the rolling stand, to calculate a respective control variable for at least one actuator associated with the rolling stand, and to operate the actuator in accordance with the calculated respective control variable.

[0002] The invention is further based on a control program for a control device of a rolling stand for rolling metal strip, the control program comprising a machine code which can be processed by the control device, said processing of the machine code by the control device ensuring that the control device is operated in accordance with such operating method.

[0003] The invention is further based on a control device for a rolling stand of a rolling mill, the control device being programmed with such a control program such that in operation the control device executes such control program.

[0004] The invention is further based on a rolling mill having at least one rolling stand, an uncoiler arranged upstream of said rolling stand and a control device for the rolling stand. [Background technology]

[0005] Such an operating method is known, for example, from German Patent No. DE 34 13 269 C2. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] German Patent No. DE 34 13 269 C2 [Patent Document 2] European Patent Publication No. EP 3 202 502 A1 Summary of the Invention [Problem to be solved by the invention]

[0007] When rolling a metal strip, the metal strip being rolled often skids, i.e. is displaced across the width of the metal strip. Such displacements can occur both at the entry side of the rolling stand and at the exit side of the rolling stand. As a result, in the case of a multi-stand rolling train, they can also occur between the individual stands of the rolling train.

[0008] Small lateral slippages are often not problematic. However, in the case of large lateral slippages, the metal strip can abut against the lateral guides, resulting in so-called cobbles. Furthermore, the lateral slippages affect the quality parameters of the rolled metal strip, such as the profile, the flatness and even the thickness wedge. This also applies for smaller lateral slippages of the metal strip.

[0009] It is known in the prior art to detect the lateral offset of the metal strip at the exit side of a rolling stand, for example by means of a camera, and to set control variables for the actuators of the rolling stand depending on the offset detected at the exit side. Purely by way of example, reference may be made to European Patent No. EP 3 202 502 A1.

[0010] It is also already known to detect the lateral offset of the metal strip at the inlet side of a rolling stand and to set control variables for the actuators of the rolling stand depending on the offset detected at the inlet side. Purely by way of example, reference may be made to the already mentioned German patent DE 34 13 269 C2.

[0011] In German Patent DE 34 13 269 C2, the lateral offset of this portion of the metal strip is detected at the inlet side of the rolling stand in each case for an individual portion and is utilized as part of a conventional adjustment system (e.g. a proportional adjustment system).

[0012] The procedure in German Patent DE 34 13 269 C2 can only be carried out when the metal strip is present as a flat metal strip, ie not in the form of a coil of metal strip.

[0013] The object of the invention is to create an option that also makes it possible to take into account the lateral offset of each portion of a metal strip when the metal strip is wound into a coil and when the metal strip is uncoiled before being rolled in a rolling stand. [Means for solving the problem]

[0014] This object is achieved by means of an operating method having the features of claim 1. Advantageous embodiments of this operating method are the subject matter of dependent claims 2 to 4.

[0015] According to the invention, an operating method of the first-mentioned type is designed in such a way that the contour of at least one end side of the still wound coil is made known to the control device once before the metal strip is unwound, so that information about the lateral offsets of the portions over the entire length of the metal strip is already available to the control device before the metal strip is fed to the rolling stand, and the control device uses the contour to calculate the respective lateral offsets.

[0016] The actuators may in particular be actuators which ensure an asymmetric adjustment of the roll gap, so that it is possible to directly influence the transverse strip running. A typical example of such an actuator is a wedge setting device of the roll gap. Alternatively or additionally, however, the control variables may also be calculated for other actuators, in particular actuators which have only a local influence on the profile and flatness of the metal strip, or a global, but symmetric influence. A typical example of a locally active actuator is a cooling device which acts only on individual parts of the working rollers, seen in the width direction of the metal strip. A typical example of an actuator which acts globally, but symmetrically, is a roller bending device. A further typical example is a roller shifting device.

[0017] In the simplest case, the control variables are calculated according to a conventional target / actual control system, for example with a P-, PI- or PID-controller. However, thanks to the fact that the progression of the lateral offset is already known in advance from the end side contour over the entire length of the metal strip, more complex adjustments are also possible, for example model-predicted adjustments. Furthermore, different types of forward consideration of the progression of the lateral offset are also possible. For example, an offline optimization of the control variables over the entire length of the strip can be performed in advance.

[0018] Typically, only the contours of the individual end sides of the coil are known to the control device. In this case, only the lateral offsets can be calculated by the control device when viewed over the length of the metal strip, assuming that the width of the metal strip is constant. Alternatively, however, it is also possible for the contours of both end sides of the coil to be known to the control device. In this case, the control device can calculate not only the respective lateral offsets, but also, for example, the respective widths of the metal strip for the individual parts of the metal strip, and take them into account when operating the rolling stand. This is advantageous in particular when the width of the metal strip can be influenced by actuators. In particular, in this case, the actuators can be the actuators of the rolling stand itself or actuators associated with the rolling stand, for example loopers arranged upstream or downstream of the rolling stand, or edgers arranged upstream or downstream of the rolling stand.

[0019] In principle, the capture of the end side contour can take place at any desired time after the metal strip has been wound to form a coil, in particular immediately after winding or at different times between winding and being fed to the uncoiler. However, the end side contour is preferably captured by means of a capture device associated with the uncoiler while the coil is already in the uncoiler and then fed to the control device. As a result, there are few links to externally supplied or provided data in the execution of the operating method.

[0020] The capture device may for example be a thermal imaging camera or a camera operating with light in the visible range, with which a conventional two-dimensional image is captured. It may also be a camera used to capture depth images. It is also possible for the capture device to be designed as a laser scanner used to scan the contour of the end face. Other embodiments are also possible. All known types of capture devices are generally known to the person skilled in the art.

[0021] In a preferred embodiment of the method of operation, the contours of the coil end sides are made known to the control device in the form of contour lines running radially inwards and outwards about the coil end sides, the contour lines thus specifying the lateral positions of the captured strip edges as a function of distance from the coil eye, the control device then uses the contour lines to calculate the respective lateral offsets.

[0022] Alternatively, the contour of the coil end side is made known to the control device in the form of a two-dimensional contour surface for the coil end side. In this case, it is of course possible to use the two-dimensional contour surface directly. In this case, however, the control device preferably calculates contour lines running radially from the middle to the outside for the coil end side based on the contour surface, and further calculates the respective lateral offsets using the contour lines rather than the two-dimensional contour surface itself. As mentioned above, the contour lines specify the lateral positions of the captured strip edges as a function of the distance from the coil eye.

[0023] The amount of computation required to calculate each lateral offset is significantly reduced by using the contour lines.

[0024] Thanks to the contours, the offset (=current location on the radial contours) of the respective part of the metal strip with the current coil radius is first of all made known to the control device. This location corresponds to a support point when viewed in the longitudinal direction of the metal strip. The distance to the next support point is obtained by the current coil radius (multiplied by the coefficient 2π). The new coil radius is obtained by the current coil radius and the thickness of the coiled metal strip. If the working direction is from outside to inside, the coil radius decreases and therefore the thickness of the coiled metal strip is subtracted. If the working direction is from inside to outside, the coil radius increases and therefore the thickness of the coiled metal strip is added. Thus, the offset of the corresponding part of the metal strip is made known to the control device only by the contours at the support points that follow one another in the longitudinal direction of the strip. The support points are not equidistant because the coil radius changes, but this is of little importance.

[0025] It is possible that the portions of the metal strip are defined by the support points themselves, i.e. a 1:1 association is made. Alternatively, however, it is also possible to perform an interpolation as required. The interpolation may be linear or non-linear as required.

[0026] As part of the operating method according to the invention, the metal strip may be cold or hot rolled as required in a rolling stand. In particular in the case of hot rolling, the rolling mill may take the form of, for example, a Steckel mill. In the case of cold rolling, by contrast, the rolling stand may in particular be the front stand of a tandem rolling train.

[0027] The object is further achieved by a control program having the features of claim 5. According to the invention, the processing of the control program by the control device comprises: - before the metal strip is unwound by an uncoiler arranged upstream of the rolling stand, the contour of at least one end side of the still wound coil is made known to the control device once, so that information regarding a lateral offset that a portion of the metal strip has at a given distance upstream from the rolling stand over the entire length of the metal strip is available to the control device, - the control device uses the contours for those parts to calculate their respective lateral offsets; and - ensuring that the control device calculates respective control variables for at least one actuator associated with the rolling stand utilizing respective lateral offsets and actuates the actuator in accordance with the calculated respective control variables.

[0028] The control program can be designed in an advantageous manner. Embodiments of the control program correspond to advantageous embodiments of the operating method. The same applies for the advantages achieved thereby.

[0029] The object is further achieved by a control device having the features of claim 8. According to the invention, the control device is programmed with a control program according to the invention so as to execute the control program according to the invention during operation.

[0030] The object is further achieved by a rolling mill having the features of claim 9. According to the invention, in the case of a rolling mill of the initially mentioned type, the control device takes the form of a control device according to the invention.

[0031] The capture device, by means of which the end side contour is captured while the coil is already in the uncoiler and then fed to the control device, is preferably associated with the uncoiler, so that the operation of the rolling mill according to the invention has few links to externally supplied or provided data.

[0032] The rolling stands of the rolling mill may take the form of hot or cold rolling stands as appropriate, in the former case in particular a Steckel mill, and in the latter case in particular the front stand of a multi-stand tandem rolling train.

[0033] The above-mentioned characteristics, features and advantages of the present invention, as well as the manner in which they are achieved, will become clearer and more easily understood when read in conjunction with the following description of exemplary embodiments, which are generally illustrated and are set forth in detail in conjunction with the drawings, in which: [Brief description of the drawings]

[0034] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIGS. 1 and 2. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] In FIG. 1 the rolling mill has a rolling stand 1. Only the working rollers of the rolling stand 1 are illustrated. In the embodiment according to FIG. 1 the rolling stand 1 is the only rolling stand of the rolling mill. An uncoiler 2 is arranged upstream of the rolling stand 1. A coil 3, i.e. a coiled metal strip 4, is uncoiled by the uncoiler 2. Starting from the uncoiler 2, the uncoiled metal strip 4 is fed to the rolling stand 1. The metal strip 4 is rolled in the rolling stand 1. The coil 3 may be fed to the uncoiler 2 as such, i.e. as a metal strip 4 previously coiled in another way. Alternatively, the metal strip may be coiled to form the coil 3 before uncoiling by the uncoiler 2 itself.

[0036] In the embodiment according to Fig. 1, a coiler 5 is further arranged downstream of the rolling stand 1. After being rolled in the rolling stand 1, the metal strip 4 is wound up by the coiler 5. The operation of the rolling mill according to Fig. 1 is generally performed in such a way that the metal strip 4 is reverse rolled in the rolling stand 1, so that the ends of the metal strip 4 are not rolled at the same time. The uncoiler 2 and the coiler 5 therefore switch their respective functions for every rolling pass. In particular, in such an embodiment, the metal strip 4 is alternately wound up and then unwound by the same reel 2, 5.

[0037] The rolling mill according to FIG. 1 can in particular take the form of a Steckel mill. In a Steckel mill, the metal strip 4 is hot rolled. In this case, the rolling stand 1 therefore takes the form of a hot rolling stand. The hot rolling of the metal strip 4 is however also possible in other embodiments of the rolling mill. For example, the hot rolling of the metal strip 4 can also take place in a multistand hot rolling train, in which the uncoiler 2 is arranged upstream of the hot rolling train. In the embodiment of the rolling train as illustrated in FIG. 1, the rolling stand 1 can also be a roughing stand.

[0038] Figure 2 shows an alternative embodiment of the rolling mill. According to Figure 2, the rolling mill has in addition to the rolling stand 1 a further rolling stand 6. The rolling stand 1 is in the latter case the front rolling stand of a multi-stand rolling train. Analogously to Figure 1, only the working rollers of the rolling stands 1, 6 are illustrated.

[0039] Also in the embodiment according to Fig. 2, an uncoiler 2 is arranged upstream of the rolling stand 1. A coil 3, i.e. a pre-coiled metal strip 4, is supplied by the uncoiler 2. The metal strip 4 is uncoiled by the uncoiler 2 and is supplied from there to the rolling stand 1 (and further rolling stand 6). The metal strip 4 is rolled in the rolling stand 1 (and also in the further rolling stand 6).

[0040] As already mentioned, the hot rolling of the metal strip 4 can also be carried out in the embodiment according to Fig. 2. However, according to Fig. 2, the S-roller set 7 is arranged between the uncoiler 2 and the rolling stand 1. Such an embodiment is customary in particular in the case of multi-stand tandem rolling trains, in which the cold rolling of the metal strip 4 is carried out. However, the cold rolling of the metal strip 4 is also possible in other embodiments of the rolling mill.

[0041] 1 and 2, at least the rolling stand 1 (and generally the entire rolling mill) is controlled by a control device 8. The control device 8 is programmed with a control program 9 such that, in operation, the control device 8 executes the control program 9. The control program 9 comprises a machine code 10 which can be processed by the control device 8. The processing of the machine code 10 by the control device 8 ensures that the control device 8 operates at least the rolling stand 1 (and generally the entire rolling mill, as already mentioned) according to the operating method which is explained below in conjunction with FIG. 3.

[0042] According to Fig. 3, the outer shape K of at least one of the two end sides 11 of the coil 4 is made known to the control device 8 in step S1. It is also possible that the outer shapes K of both end sides 11 of the coil 4 are made known to the control device 8 in step S1. However, as a general rule, the outer shape K of one end side 11 of the two end sides 11 is sufficient. This case will therefore be assumed below. Step S1 is carried out by the control device 8 before the metal strip 4 is unwound.

[0043] In step S2, the control device 8 calculates a respective lateral offset V for the portion i (i=1, 2, 3, ...) of the metal strip 4. The respective offset V can therefore vary when viewed from above the portion i. The offset V corresponds to the deviation of the centre line of the metal strip 4 from the centre line of the rolling stand 1 when viewed in the width direction of the metal strip 4. The offset V of each portion i is determined for a given distance that the respective portion i has from the rolling stand 1. The determination of the offset V is performed with the aid of the contour K.

[0044] The predetermined distance can be determined as required. In particular, it can be an arrangement in which the metal strip 4 separates from the rest of the coil 3. Fixing the predetermined distance can be particularly expedient when there are no devices between the uncoiler 2 and the rolling stand 1 that influence or impede the lateral movement of the metal strip 1. However, this can also be in a different arrangement. For example, in the case of the embodiment of FIG. 2, the predetermined distance can be determined by the arrangement of the S roller set 7. Which arrangement is chosen depends on the circumstances of the individual case.

[0045] In step S3, the control device 8 calculates a respective control variable C for at least one actuator 12. The actuator 12 may be an actuator of the rolling stand 1 itself and may act, for example, locally or globally on the roll gap. Alternatively, the actuator 12 may be arranged upstream or downstream of the rolling stand 1. The calculation of the respective control variable C is a valid calculation for each portion i of the metal strip 4. The respective control variable C is calculated by the control device 8 with the aid of the respective lateral offset V. Suitable actuators 12, suitable control variables C and suitable calculation methods are known to the person skilled in the art. In step S4, the control device 8 activates the actuator 12 according to the calculated respective control variable C.

[0046] Step S1 is carried out only once, i.e. once before the metal strip 4 is fed into the rolling stand 1. Step S4 is carried out repeatedly, i.e. in each case for an individual portion i of the metal strip 4. Steps S2 and S3 can be carried out only once or repeatedly. Which procedure is adopted for steps S2 and S3 is at the discretion of the person skilled in the art. It is often advantageous to carry out step S2 together with step S1, i.e. once beforehand, and step S3 together with step S4, i.e. repeatedly.

[0047] The manner in which the contour K of the end side 11 is made known to the control device 8 can be determined as required. For example, it is possible that the contour K is specified to the control device 8 by an operator or by a higher-level control device. However, the capture device by which the contour K of the end side 11 is captured while the coil 3 is already in the uncoiler 2 is preferably associated with the uncoiler 2. In this case, the capture device 13 supplies the captured contour K to the control device 8. The control device 8 receives the captured contour K from the capture device 13. In this way, the contour K is made known to the control device 8.

[0048] A preferred manner in which the contour K is made available to the control device 8 is calculated below in conjunction with FIGS.

[0049] FIG. 4 shows a cross section along the line IV-IV in FIG. 1 and FIG. 2. According to FIG. 4, the coil 3 has a coil eye 14. The coil eye 14 has a diameter D1. R1=D1 / 2 is therefore the minimum radius of the coil 3. The coil 3 further has an outer diameter D2. R2=D2 / 2 is therefore the maximum radius of the coil 3. The metal strip 4 has a thickness d. The individual turns 15 of the coil 3 are in each case spaced apart from one another in the radial direction of the coil 3 (i.e. when viewed from the inside out or conversely from the outside in) by the thickness d of the metal strip 4. Furthermore, the individual turns 15 of the coil 3 are slightly offset with respect to one another in the transverse direction (i.e. when viewed in the width direction of the metal strip 4). The outer shape K of the end side 11 follows the slight transverse offset of the turns 15. The result is therefore a contour KL which describes the offset of the turns 15 as a function of the current coil radius r in each case from R1 to R2, i.e. from radially inwards to outwards (or vice versa), when viewed along the straight line of the section IV-IV (see Figures 1 and 2), with respect to the corresponding end side 11 of the coil 3. An entirely similar contour KL would result if the straight line of the section through the coil 3 were made in another way.

[0050] According to FIG. 5, the control device 8 is able to receive in step S11 the outer shape K of the end side 11 of the coil 3 in the form of such a contour line KL.

[0051] The placement of the outermost turn 15 corresponds to the beginning of the metal strip 4. The value of the contour KL at this point corresponds to the offset of the frontmost part i=1 of the metal strip 4. The radius r for the next innermost turn 15 can be easily calculated by subtracting the thickness d of the metal strip 4 from the radius r. At this point of the metal strip 4, the contour KL can be evaluated again by the control device 8. This procedure can be repeated for all turns 15 of the metal strip 4, one at a time. Thus, in step S12, the control device 8 can calculate in each case the lateral offset of the metal strip 4 at this point, one at a time, for all turns 15, and thus for the support points that are spaced from each other by a distance of 2πr (the current coil radius r is variable). Thus, as a result, a functional chain for the lateral offset of the metal strip 4 over the entire length of the metal strip 4 is created. The lateral offset V for the part i can be easily calculated based on this offset.

[0052] In the simplest case, the parts i are determined by the support points. In this case, the parts i are not the same size. If the parts i need to be the same size or meet another criterion, interpolation can be done between adjacent support points as necessary.

[0053] Steps S11 and S12 thus correspond to possible implementations of steps S1 and S2 of FIG.

[0054] A further preferred manner in which the contour K is made available to the control device 8 is calculated below in conjunction with FIGS.

[0055] 6 is a perspective view of the end side 11 of the coil 3. Using a suitable capture device 13, it is easily possible to calculate a contour surface KF that replicates as if it were a three-dimensional "offset mountain range" over the entire end side 11. A two-dimensional scan of the complete end side 11 can be performed, for example, if the capture device 13 takes the form of a laser scanner. However, other procedures are possible.

[0056] According to Fig. 7, it is possible for the control device 8 to receive in step S21 the contour K of the end side 11 of the coil 3 in the form of such a contour surface KF. In this case, the control device 8 can, for example, calculate the contour lines KL on the basis of the contour surface KF in step S22. In particular, the control device 8 can select and evaluate narrow strips of the contour surface KF, which run radially from the center to the outside. In step S23, the control device 8 can then use the contour lines KL to calculate the respective lateral offsets V of the portions i. The contour surface KF itself is no longer required to carry out step S23. Step S23 of Fig. 7 may therefore correspond in content to step S12 of Fig. 5.

[0057] Steps S21 to S23 thus correspond to a further possible implementation of steps S1 and S2 of FIG.

[0058] The invention has many advantages. Information about the transverse offset V of the section i over the entire length of the metal strip 4 can be obtained in a simple manner by capturing the contour K of the end side 11. As a result, particularly good adjustment algorithms can be implemented. An independent capture that is not based on external inputs is performed by a direct capture in the uncoiler 2. Furthermore, it is guaranteed that influences occurring before the coil unwinding are reliably identified and taken into account. The solution according to the invention is simple, robust, reliable and can also be retrofitted to existing rolling mills.

[0059] Although the present invention has been illustrated and described in detail by means of preferred exemplary embodiments, the present invention is not limited to the disclosed examples, and other modifications can also be derived by those skilled in the art without exceeding the scope of protection of the present invention. [Explanation of symbols]

[0060] 1 Rolling stand 2. Uncoiler 3 Coil 4 Metal Strips 5. Coiler 6 Further rolling stands 7 S Roller Set 8 Control Devices 9 Control Program 10 Machine Code 11 End side 12 Actuator 13 Capture Device 14 Coil Eyes 15 rolls C Control variables D1, D2 diameter d Strip thickness i Metal strip section K External shape KF external surface KL Contours R1, R2, r radius Steps S1 to S23 V Offset

Claims

1. A method for operating a rolling mill having at least one rolling stand (1) and an uncoiler (2) arranged upstream of said rolling stand (1), comprising the steps of: - in the rolling mill, the coiled metal strip (4) is uncoiled by the uncoiler (2) and is fed from there to the rolling stand (1) where it is rolled, - a control device (8) for said rolling stand (1) uses a respective lateral offset (V) that each portion (i) of the metal strip (4) has at a predetermined distance upstream from said rolling stand (1) to calculate a respective control variable (C) for at least one actuator (12) associated with said rolling stand (1) and activates said actuator (12) according to said calculated respective control variable (C); 13. A method of operating according to claim 12, characterized in that the contour (K) of at least one end side (11) of the still wound coil (3) is made known to the control device (8) once before the metal strip (4) is unwound, so that information regarding the transverse offsets (V) of the portions (i) over the entire length of the metal strip (4) is already available to the control device before the metal strip (4) is fed to the rolling stand (1), and the control device (8) uses the contour (K) to calculate the respective transverse offsets (V).

2. 2. The method according to claim 1, characterized in that the outer shape (K) of the end side (11) is captured by means of a capture device (13) associated with the uncoiler (2) while the coil (3) is already in the uncoiler (2) and then fed to the control device (8).

3. - the outer shape (K) of the end side (11) of the coil (3) is made known to the control device (8) in the form of a contour line (KL) running radially from the center to the outside with respect to the end side (11) of the coil (3), and the control device (8) uses the contour line (KL) to calculate the respective lateral offset (V), or 3. The method according to claim 1 or 2, characterized in that the contour (K) of the end side (11) of the coil (3) is made known to a control device (8) in the form of a two-dimensional contour surface (KF) with respect to the end side (11) of the coil (3), the control device (8) calculates contour lines (KL) running radially from the middle to the outside with respect to the end side (11) of the coil (3) based on the contour surface (KF), and the control device (8) calculates the respective lateral offsets (V) with the aid of the contour lines (KL) and not with the two-dimensional contour surface (KF) itself.

4. 4. A method according to claim 1, 2 or 3, characterized in that the metal strip (4) is cold rolled or hot rolled in the rolling stand (1).

5. A control program for a control device (8) of a rolling stand (1) for rolling a metal strip (4), said control program comprising a machine code (10) which can be processed by said control device (8), said processing of said machine code (10) by said control device (8) comprising: - the outer shape (K) of at least one end side (11) of the still wound coil (3) is made known to the control device (8) once before the metal strip (4) is unwound by an uncoiler (2) arranged upstream of the rolling stand (1), so that information is available from the control device (8) about the lateral offset (V) that a portion (i) of the metal strip (4) has at a given distance upstream from the rolling stand (1) over the entire length of the metal strip (4); - said control device (8) calculating said respective lateral offsets (V) using said contours (K) for said portions (i); and a control program ensuring that said control device (8) calculates a respective control variable (C) for at least one actuator (12) associated with said rolling stand (1) using said respective lateral offset (V) and actuates said actuator (12) in accordance with said calculated respective control variable (C).

6. 6. A control program according to claim 5, characterized in that the processing of the machine code (10) by the control device (8) ensures that the control device (8) receives the outer shape (K) of the end side (11) from a capture device (13) associated with the uncoiler (2) while the coil (3) is already in the uncoiler (2).

7. The processing of the machine code (10) by the control device (8) comprises: - said control device (8) receives the outer shape (K) of said end side (11) of said coil (3) in the form of contour lines (KL) running radially from the middle to the outside with respect to said end side (11) of said coil (3) and calculates said respective lateral offsets (V) using said contour lines (KL); 7. A control program according to claim 5 or 6, characterized in that the control device (8) receives the contour (K) of the end side (11) of the coil (3) in the form of a two-dimensional contour surface (KF) for the end side (11) of the coil (3), calculates contour lines (KL) running radially from the middle to the outside for the end side (11) of the coil (3), and calculates the respective lateral offsets (V) using the contour lines (KL) and not the two-dimensional contour surface (KF).

8. A control device for a rolling stand (1) of a rolling mill, the control device being programmed with a control program (9) according to claim 5, 6 or 7 so as to execute the control program (9) during operation of the control device.

9. 9. A rolling mill having at least one rolling stand (1), an uncoiler (2) arranged upstream of said rolling stand (1) and a control device (8) for said rolling stand (1), characterized in that said control device (8) takes the form of a control device as claimed in claim 8.

10. 10. Rolling mill according to claim 9, characterized in that a capture device (13) is associated with the uncoiler (2) by means of which the contours (K) of the end sides (11) are captured while the coil (3) is already in the uncoiler (2) and then fed to the control device (8).

11. 11. Rolling mill according to claim 9 or 10, characterized in that the rolling stand (1) takes the form of a hot rolling stand, in particular that the rolling mill takes the form of a Steckel mill, or that the rolling stand (1) takes the form of a cold rolling stand, in particular the front rolling stand of a multi-stand tandem rolling train.

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