EP3858503B1 - Rolling mill with material property dependent rolling - Google Patents

Description

field of technology

• wobei vor und/oder hinter dem ersten Walzgerüst eine Sensoreinrichtung angeordnet ist,
• wobei die Sensoreinrichtung zum Übermitteln der erfassten Messgröße mit einer Steuereinrichtung für das Walzwerk verbunden ist,
• wobei die Steuereinrichtung derart ausgebildet ist, dass sie die übermittelte Messgröße im Rahmen der Ermittlung eines Ansteuerwertes für das erste Walzgerüst berücksichtigt,
• wobei das Ansteuern des ersten Walzgerüsts mit dem Ansteuerwert die Werkstoffeigenschaft des flachen Walzguts beeinflusst,
• wobei das erste Walzgerüst eine obere Arbeitswalze und eine untere Arbeitswalze aufweist.

The present invention is based on a rolling mill with a first rolling stand for rolling a flat rolling stock made of metal,

• a sensor device being arranged in front of and/or behind the first roll stand,
• wherein the sensor device is connected to a control device for the rolling mill in order to transmit the measured variable,
• wherein the control device is designed in such a way that it takes the transmitted measured variable into account when determining a control value for the first roll stand,
• the activation of the first roll stand with the activation value influencing the material property of the flat rolling stock,
• wherein the first rolling mill has an upper work roll and a lower work roll.

In the context of the present invention, the term “first rolling stand” does not mean that the rolling mill necessarily has a plurality of rolling stands and the first rolling stand is the foremost rolling stand through which the flat rolling stock passes first. Rather, the case should first be included that the rolling mill has only the first roll stand. In this case, only the first roll stand is present. Furthermore, even if the rolling mill has a plurality of rolling stands, the term “first rolling stand” only serves to distinguish it from the other rolling stands of the rolling mill. However, no order should be implied. In this case, too, the first roll stand can be arranged at any point in the sequence of roll stands of the rolling mill. So if - purely by way of example - the flat rolling stock first runs through a roll stand A, then a roll stand B, then a roll stand C and finally a roll stand D, the first roll stand can be any one of the roll stands A to D, while the other rolling stands are second rolling stands.

When producing a flat rolled stock, the aim is to set the geometric properties of the flat rolled stock, ie in particular its width and its thickness, with the greatest possible precision. The same applies to the profile or the contour. Flatness should also be maintained. In addition to these and possibly also other geometric properties, material properties of the flat rolling stock should also be adjusted. Material properties are properties that the flat rolling stock should have when it is later used, for example a certain yield point, a certain material hardness or a certain magnetizability. Material properties are properties that the material exhibits independently of its specific current state (such as temperature) and also independently of its geometric properties. The reason for certain material properties is - in addition to the material as such - the grain structure of the metal.

Material properties can be adjusted—at least partially—during the rolling of the flat rolling stock. However, there often remains a difference in the actual value of a material property from a desired target value. In this case, it is necessary to thermally treat the flat rolled stock after hot rolling. This applies in particular if a certain so-called Goss texture is to be set for the rolling stock. However, similar problems also arise with certain steels, in particular with AHSS (= advanced high strength steel) as well as martensitic and bainitic grades. In the case of a thermal treatment, the rolling stock can be cooled in a suitable manner in a cooling zone, for example after hot rolling, or treated in an annealing machine as part of the cold rolling, in order to set material properties. This treatment can be alternative after cold rolling or between two cold rolling steps.

State of the art

From the essay " Forming technology for electromobility" by Gerhard Hirt et al , it is known that so-called asymmetrical rolling can be advantageous for setting a texture of the rolling stock that is favorable for magnetization. In asymmetric rolling, the peripheral speeds of an upper and a lower work roll of a rolling mill differ from each other. During rolling, shear forces act on the flat rolling stock in the transport direction. Due to the shear forces, a rearrangement of the crystal orientation is brought about.

A rolling mill of the type mentioned is for example from WO 2017/157692 A1 known. In this rolling mill, for example, the reduction thickness or the rolling force is set by the control value.

Summary of the Invention

The object of the present invention is to create possibilities by means of which a material property of the flat rolling stock can be adjusted in a targeted manner in a simple and reliable manner.

The object is achieved by a rolling mill having the features of claim 1. Advantageous configurations of the rolling mill are the subject matter of dependent claims 2 to 16.

According to the invention, in a rolling mill of the type mentioned at the outset, the control device is designed in such a way that the control value determined taking into account the measured variable is a ratio of an upper peripheral speed at which the upper work roll rotates to a lower peripheral speed at which the lower work roll rotates.

So a measured variable is recorded, which can be used to directly determine the corresponding material property of the flat rolling stock Time of measurement can be determined. There is therefore a direct functional relationship between the measured variable on the one hand and the material property on the other. On the other hand, it is not necessary to carry out complicated model calculations, by means of which, for example, a development over time is modeled.

The wording "at the time of the measurement" is not intended to imply that the material property also automatically changes over time due to the change in the condition of the flat rolling stock, such as its temperature. However, the material property can be adjusted to a different value at a later point in time by appropriate treatment of the rolling stock, for example by rolling in the first roll stand or by rolling in another roll stand or by thermal treatment.

It is possible that the rolling mill has only said first roll stand and consequently only a single roll stand. In this case, the sensor device is arranged all by itself directly in front of or directly behind the roll stand. However, it is also possible for the rolling mill to have at least one second rolling stand in addition to the first rolling stand. In this case, several different configurations are possible.

For example, it is possible that the second roll stands are not arranged between the sensor device and the first roll stand. This configuration is implemented, for example, when the sensor device is arranged in front of the foremost rolling stand of a multi-stand rolling train and the control value determined by the control device, taking into account the measured variable, acts on the front rolling stand or, conversely, the sensor arrangement is arranged behind the last rolling stand of a multi-stand rolling train and the control value determined by the control device, taking into account the measured variable, on the last roll stand works. This configuration is also realized, for example, when the sensor arrangement is arranged between two roll stands of a multi-stand rolling train and the control value determined by the control device, taking into account the measured variable, acts on one of these two roll stands, or the control device determines two such control values, one of which is applied to each one of these two roll stands acts.

Alternatively, it is possible for at least one of the second roll stands to be arranged between the sensor device and the first roll stand. This configuration is implemented, for example, when the sensor device is arranged in front of the frontmost roll stand of a multi-stand rolling train and the control value determined by the control device, taking into account the measured variable, acts on a roll stand other than the frontmost roll stand, or, conversely, the sensor arrangement is arranged behind the last roll stand of a multi-stand rolling train and the control value determined by the control device, taking into account the measured variable, acts on a roll stand other than the last one.

Of course, combinations of these procedures are also possible. For example, the sensor device can be arranged in front of the foremost roll stand of the multi-stand rolling train and several control values can also be determined by the control device, taking into account the measured variable, of which one acts on the front roll stand and another on another roll stand. Conversely, the sensor arrangement can also be arranged behind the last roll stand of the multi-stand rolling train and the control device can also determine several control values, taking into account the measured variable, of which one acts on the last roll stand and another on another roll stand.

The first rolling mill has an upper work roll and a lower work roll. The control device is designed such that the under Taking into account the measured variable, the control value determined is a ratio of an upper peripheral speed, at which the upper work roll rotates, to a lower peripheral speed, at which the lower work roll rotates. This procedure can be advantageous, for example, for adjusting electrical or magnetic properties of the flat rolling stock. However, it can also be used to adjust the mechanical properties of the flat rolling stock.

The control device is preferably designed in such a way that it determines the ratio of the upper peripheral speed to the lower peripheral speed in such a way that it is between 0.5 and 2.0, in particular between 0.9 and 1.1. This means that all cases relevant in practice can be covered.

In order to be able to realize peripheral speeds that differ from one another, it is possible for the upper work roll to be driven by an upper drive and for the lower work roll to be driven by a lower drive that is different from the upper drive. In this case, the different peripheral speeds can easily be implemented by appropriately setting the two drives to different speeds.

Alternatively, it is possible for the upper work roll and the lower work roll to be driven by a common drive. In this case, a gear is arranged between the common drive on the one hand and the upper work roll and the lower work roll on the other side, by means of which a ratio of a speed of an upper output shaft of the gear, which is non-rotatably connected to the upper work roll, to a speed of a the lower work roll non-rotatably connected lower output shaft of the transmission is continuously adjustable.

Alternatively or in addition to setting a ratio of the peripheral speeds to one another, it is possible for the control device to be designed in such a way that the control value determined taking into account the measured variable influences the temperature of the upper work roll and/or the lower work roll of the first roll stand and/or the flat rolling stock before rolling in the first rolling stand. For example, cooling can be effected by spraying on water, or heating can be effected by induction heating.

If the sensor device is arranged in front of the first roll stand, the control device is preferably designed in such a way that it outputs the control value determined taking into account the measured variable, taking into account a path tracking of the flat rolling stock from the sensor device to the first roll stand to the first roll stand. When activating the first roll stand, the control device therefore takes into account the transport time that elapses between the detection of the measured variable for a specific section of the flat rolled stock and the rolling of the same section of the flat rolled stock in the first roll stand.

The control device preferably includes a model, by means of which the control device determines the control value for the first roll stand, taking into account the measured variable, and also determines an expected value for the material property of the flat rolling stock after rolling in the first roll stand, taking into account the control value determined taking the measured variable into account. Furthermore, a further sensor device is preferably arranged behind the first roll stand, by means of which at least one further measured variable characteristic of the material property of the flat rolling stock after rolling in the first roll stand can be detected. The additional sensor device is connected to the control device in order to transmit the recorded additional measured variable. Finally, the control device is preferably designed such that it further Measured variable for a point in time that is determined by the control device, taking into account a path tracking of the flat rolling stock from the first roll stand to the further sensor device, and the model is adapted based on a comparison of the further measured variable and the expected value of the material property. With this procedure, the model can gradually be better adapted to the actual behavior of the flat rolling stock.

The control device is preferably designed in such a way that, when determining the control value, it also measures the temperature of the flat rolling stock prior to rolling of the flat rolling stock in the first rolling stand and/or the rolling force during rolling of the flat rolling stock in the first rolling stand and/or the measured variable that is transmitted. or the reduction in the rolling of the flat rolled stock in the first roll stand is taken into account. As a result, the desired material properties can be set with greater accuracy. The required dependencies can be stored in the control device, for example in the form of characteristic curve fields.

In a preferred embodiment, the sensor device includes an excitation element and a first sensor element. A base signal is excited in the flat rolling stock by means of the excitation element. A first sensor signal based on the excited base signal is detected by means of the first sensor element. It is possible for the sensor device to determine the transmitted measurement variable taking into account the first sensor signal. Alternatively, it is possible for the measured variable transmitted to include the first sensor signal.

In individual cases it can be possible that only the first sensor signal is detected. As a rule, however, the sensor device also includes a number of second sensor elements. In this case, viewed from the first sensor element in the transport direction, the respective second sensor element is arranged in front of or behind the first sensor element and/or laterally offset. By means of the respective second Sensor element, a respective second sensor signal, which is based on the excited base signal and is similar to the first sensor signal, is detected. It is possible for the sensor device to determine the transmitted measured variable, also taking into account the respective second sensor signal. For example, the difference or the quotient of the corresponding sensor signals can be formed. Alternatively, it is possible that the transmitted measured variable also includes the respective second sensor signal. In this case, similar evaluations can be carried out by the control device.

The base signal can be an eddy current, for example. Alternatively, the base signal can be a sound signal, in particular an ultrasonic signal.

A connecting line from the excitation element to the first sensor element preferably runs parallel to the transport direction. This results in a particularly reliable evaluation.

As already mentioned, the material property can be an electromagnetic property or a mechanical property of the rolling stock.

In individual cases, hot rolling can take place. As a rule, however, cold rolling takes place. The rolling mill is thus usually a cold rolling mill.

Brief description of the drawings

FIG 1

ein Walzwerk mit einem ersten Walzgerüst,

FIG 2

eine Draufsicht auf einen Teil des Walzwerks von FIG 1,

FIG 3 und 4

Seitenansichten von FIG 3 zu zwei Zeitpunkten,

FIG 5

ein Ablaufdiagramm,

FIG 6

eine Draufsicht auf einen Teil des Walzwerks von FIG 1,

FIG 7 und 8

Seitenansichten von FIG 6 zu zwei Zeitpunkten,

FIG 9 und 10

jeweils ein weiteres Walzwerk mit einem ersten Walzgerüst,

FIG 11

ein Ablaufdiagramm,

FIG 12 und 13

Antriebsstrukturen für Arbeitswalzen,

FIG 14

ein Walzgerüst und Temperaturbeeinflussungen und

FIG 15 bis 20

verschiedene Ausgestaltungen von Walzstraßen.

The characteristics, features and advantages of this invention described above, and the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the exemplary embodiments, which are explained in more detail in connection with the drawings. This shows in a schematic representation:

FIG 1

a rolling mill with a first roll stand,

FIG 2

a plan view of part of the rolling mill of FIG FIG 1 ,

3 and 4

side views of 3 at two times,

5

a flowchart,

6

a plan view of part of the rolling mill of FIG FIG 1 ,

7 and 8

side views of 6 at two times,

9 and 10

one further rolling mill each with a first roll stand,

11

a flowchart,

12 and 13

drive structures for work rolls,

14

a roll stand and temperature influences and

15 to 20

various configurations of rolling mills.

Description of the embodiments

According to FIG 1 has a rolling mill--like any rolling mill--at least a first roll stand 1. The first roll stand 1 is used for rolling a flat rolling stock 2 made of metal, in particular a strip. The metal from which the flat rolling stock 2 is made can, in particular, be steel or aluminum. In the case of steel, the flat rolling stock can in particular be an electrical steel sheet with a relatively high proportion of silicon (usually between 2% and 4%).

The rolling can be hot rolling. In this case, the rolling mill is a hot rolling mill. As a rule, however, it is cold rolling. In this case, the rolling mill is a cold rolling mill.

From the first roll stand 1 are in FIG 1 and only the upper work roll 3 and the lower work roll 4 are shown in the other figures. As a rule, however, the first roll stand 1 also has other rolls, for example in a four-high stand in addition to the work rolls 3, 4 back-up rolls and in a six-high stand in addition to the work rolls 3, 4 and the back-up rolls intermediate rolls between the work rolls 3, 4 and the back-up rolls. Other configurations are also possible, for example as a so-called 20-roll rolling stand. Regardless of the specific configuration, the upper work roll 3 rotates at an upper peripheral speed vO, while the lower work roll 4 rotates at a lower peripheral speed vU. Both the upper and the lower peripheral speeds vO, vU are greater than 0.

According to the representation in FIG 1 the rolling mill is designed as a reversing rolling mill. It therefore has a coiler 5 in front of and behind the first roll stand 1 for rolling the flat rolling stock 2 . In relation to the first roll stand 1, the terms “in front of” and “behind” are always to be seen in connection with the transport direction x, with which the flat rolling stock 2 is rolled in the first roll stand 1. In the case of a reversing rolling mill, the terms "before" and "after" are therefore only defined during a respective rolling pass and are reversed at the respective next rolling pass.

A sensor device 6 is arranged behind the first roll stand 1 . A measured variable M can be detected by means of the sensor device 6 . The recorded measurement variable M is characteristic of a material property of the flat rolling stock 2 . Examples of such properties are the electrical conductivity, the permeability number and the magnetic saturation or generally an electromagnetic property of the rolling stock 2. Further examples of material properties are the yield point, the yield point, the elongation at break or generally a mechanical property of the rolling stock 2. The variables mentioned can alternatively be direction-independent (i.e. isotropic) or direction-dependent (i.e. anisotropic). They are all based on the grain structure and possibly also the alignment of the grains of the metal from which the rolling stock 2 is made.

The following is in connection with the 2 to 4 a possible configuration of the sensor device 6 is explained. the However, the present invention is not limited to this embodiment of the sensor device 6 .

According to the 2 to 4 the sensor device 6 includes an excitation element 7. By means of the excitation element 7, a base signal can be excited in the flat rolling stock 2. For example, the excitation element 7 as shown in FIGS 3 and 4 be designed as a coil, which is intermittently supplied with an excitation current IA and thereby generates an eddy current IW in the rolling stock 2 as a base signal. 3 shows the sensor device 4 at a point in time when the excitation element 7 is acted upon by the excitation current IA.

The sensor device 6 also includes a first sensor element 8a. A first sensor signal Ia is detected by means of the first sensor element 8a. The first sensor signal Ia is detected after the base signal has been excited, ie at a different, later point in time. As a rule, no base signal is excited at this later point in time. However, a previously excited base signal has not yet completely decayed. The first sensor signal Ia is based on the excited base signal. For example, the first sensor element 8a as shown in FIGS 3 and 4 be designed as a coil, so that a current is induced in the first sensor element 8a due to the eddy current IW, which forms the first sensor signal Ia.

The first sensor element 8a is in the 2 to 4 shown as a different element from the excitation element 7 . This configuration represents the normal case. In this case, the first sensor element 8a is arranged behind the excitation element 7 as viewed in the transport direction x of the rolling stock 2 . In this case, a connecting line from the excitation element 7 to the first sensor element 8a preferably runs parallel to the transport direction x. In individual cases, however, the first sensor element 8a can also be identical to the excitation element 7 . This refinement can then be possible in particular be when a period of time between the excitation of the base signal and the detection of the excited base signal is sufficiently small.

The sensor device 6 is according to FIG 1 connected to a control device 9 for the rolling mill. Due to the connection of the sensor device 6 to the control device 9 , the detected measured variable M can in particular be transmitted to the control device 9 . It is possible for the transmitted measurement variable M to include the first sensor signal Ia. If the transmitted measured variable M does not contain any further components, the transmitted measured variable M can also be identical to the first sensor signal Ia. Alternatively, it is possible for the sensor device 6 to first evaluate the first sensor signal Ia (and optionally other signals) to determine the measured variable M and for the result of this evaluation to be the measured variable M. For example, the sensor device 6 can set the first sensor signal Ia in relation to the excitation signal IA and thereby determine the measured variable M.

In addition to the first sensor element 8a, the sensor device 6 often includes a number of second sensor elements 8b to 8d. The second sensor elements 8b to 8d are different from the first sensor element 8a (and usually also from the excitation element 7). Seen from the excitation element 7, the second sensor elements 8b to 8d are generally arranged behind the excitation element 7, even if this can be deviated from in individual cases. Second sensor signals Ib to Id can be detected by means of the second sensor elements 8b to 8d. The second sensor signals Ib to Id are also based on the excited base signal IW and are similar to the first sensor signal Ia. The second sensor signals Ib to Id are generally recorded simultaneously with the first sensor signal Ia.

If the second sensor elements 8b to 8d are also present, the sensor device 6 can be used as a measured variable M For example, transmit the sensor signals Ia to Id as a whole, i.e. both the first sensor signal Ia and the second sensor signals Ib to Id. In this case, the sensor signals Ia to Id are evaluated accordingly by the control device 9. Alternatively, an evaluation of the sensor signals Ia to Id (Fully or partially) are already carried out by the sensor device 6 and the result of this evaluation is transmitted as the measured variable M.

With regard to the arrangement of the second sensor elements 8b to 8d relative to the first sensor element 8a, various arrangements and configurations are possible.

For example, the sensor device 6 can have a second sensor element 8b, 8c, which is arranged laterally offset from the first sensor element 8a in the transport direction x. In this case, the sensor device 6 can set the first sensor signal Ia in relation to the second sensor signal Ib, Ic and thereby determine the measured variable M. In this case, the measured variable M can be determined in particular using the difference or the quotient of the sensor signals Ia, Ib, Ic. If, as in FIG 2 shown, a second sensor element 8b, 8c is arranged on both sides of the first sensor element 8a, the sensor device 6 can set the first sensor signal Ia in relation to the mean value of these two second sensor signals Ib, Ic.

Alternatively or additionally, it is possible for the sensor device 6 to have a second sensor element 8d, which is arranged in front of or behind the first sensor element 8a, viewed from the first sensor element 8a in the transport direction x. In this case, an arrangement behind the first sensor element 8a is the norm. Even if the second sensor element 8d is arranged in front of or behind the first sensor element 8a, the sensor device 6 can set the first sensor signal Ia in relation to the second sensor signal 8d and thus the measured variable M detect. The measurand M can also in this case, in particular based on the difference or the quotient of the sensor signals Ia, Id.

The controller 9 takes according to 5 in a step S1, the measured variable M transmitted to them. In a step S2, the control device 9 determines a control value A for the first roll stand 1. According to the representation in FIG 5 the control device 9 takes into account at least the transmitted measured variable M when determining the control value A. When determining the control value A, the control device 9 often also takes into account other variable data such as, for example, the temperature T of the flat rolling stock 2 before rolling in the first roll stand 1 and/or or the rolling force F when rolling the flat rolling stock 2 in the first rolling stand 1 and/or the reduction in thickness when rolling the flat rolling stock 2 in the first rolling stand 1. The temperature T and the rolling force F can be detected by means of appropriate sensors, which are generally known to those skilled in the art are. The pass reduction, i.e. the ratio of the exit-side thickness d2 of the flat rolling stock 2 to the entry-side thickness d1 of the flat rolling stock 2 (see FIG 1 ), the control device 9 can be known, for example, on the basis of a pass schedule. Furthermore, the control device 9 can take into account the speed of the flat rolling stock 2 in the area of the sensor device 6, in particular when evaluating the measured variable M. If necessary, the positions of the excitation element 7 and/or the sensor elements 8a to 8d can also be taken into account. In a step S3, the control device 9 controls the first roll stand 1 according to the control value A determined.

The control device 9 iteratively carries out the steps S1 to S3 again and again. A time constant with which the repetition takes place is usually in the range between 0.1 s and 1.0 s, in particular between 0.2 s and 0.5 s.

The control device 9 is designed in such a way that it takes the procedure from 5 executes The controller 9 is still as shown in FIG 1 usually designed as a software-programmable control device. In this case, the control device 9 is programmed with a control program 10 . The control program 10 includes program code 11 which can be processed by the control device 9 . The control device 9 processes the program code 11 during operation. The processing of the program code 11 by the control device 9 causes the control device 9 to be designed accordingly.

Above were in connection with the 1 to 5 Explained configurations in which the base signal is an eddy current IW and thus an electrical variable. These configurations are particularly useful if the measured variable M is intended to be characteristic of an electrical or magnetic material property. However, the configurations can also allow conclusions to be drawn about mechanical material properties.

The following is in connection with the 6 to 8 another embodiment explained. the 6 to 8 point to the 2 to 4 completely analogous configurations. The difference is that the 6 to 8 the excitation element 7 emits a sound signal, in particular an ultrasonic signal. Correspondingly, the sensor elements 8a to 8d are also designed to detect a corresponding sound signal. Otherwise, the comments on the 2 to 4 applicable in an analogous way.

9 shows a modification of the rolling mill of FIG 1 . The difference is that when designing the rolling mill according to 9 the sensor device 6 is now no longer arranged behind the first roll stand 1, but in front of the first roll stand 1. Otherwise, the statements are to FIG 1 and also the explanations based on it 2 to 8 - For example, the design of the control device 9 as software-programmable - still applicable. In accordance with the design 9 In particular, is it possible that the control device 9 outputs the control value A, which it determines taking into account the measured variable M, taking into account a path tracking of the flat rolling stock 2 from the sensor device 6 to the first rolling stand 1 to the first rolling stand 1 . The details of this are explained in connection with a further embodiment, which is described below in connection with 10 is explained.

10 goes from 9 . Same as with 9 is therefore in accordance with the design 10 the sensor device 6 is arranged in front of the first roll stand 1 . The control device 9 includes--for example due to the execution of the program code 11--a model 12. Furthermore, a further sensor device 13 is arranged behind the first roll stand 1. At least one further measured variable M′ can be detected by means of the further sensor device 13 . The further measured variable M′ recorded is characteristic of the material property of the flat rolling stock 2 as it is present after rolling in the first roll stand 1 . The other measured variable M' is therefore characteristic of the same material property as the measured variable M and is therefore similar to the measured variable M. The difference is that the measured variable βe M for the material property of the flat rolling stock 2 before rolling in the first roll stand 1 is characteristic, while the measured variable M' is characteristic of the material property of the flat rolling stock 2 after rolling in the first roll stand 1.

The additional sensor device 13 is also connected to the control device 9 for the rolling mill. Due to the connection of the additional sensor device 13 to the control device 9 , the recorded additional measured variable M′ can in particular be transmitted to the control device 9 .

The operation of the rolling mill from 10 is hereinafter referred to in connection with 11 explained. As far as the consideration of the tracking of the flat rolling stock 2 from the sensor device 6 to the first roll stand 1 to the first roll stand 1 concerns, shows 11 also the operation of the rolling mill of 9 .

According to 11 In a step S11, the control device 9 receives the measured variable M transmitted to it. Step S11 corresponds 1:1 to step S1 of FIG FIG 2 . In a step S12, the control device 9 determines the control value A for the first roll stand 1. The core of the step S12 corresponds to the step S2 of FIG FIG 2 . The difference is that the control device 9 determines the activation value A using the model 12 in step S12. Among other things, a model parameter k is included in the determination of the control value A.

In a step S13, the control device 9 determines an expected value E for the material property of the flat rolling stock 2 after rolling in the first roll stand 1, taking into account this control value A - i.e. the control value A determined in step S12. This determination is also made using the model 12 .

In a step S14, the control device 9 waits for a first waiting time t1. The first waiting time t1 corresponds to the time that a specific section of the flat rolling stock 2 needs to reach the first roll stand 1 starting from the sensor device 6 . The control device 9 thus essentially implements a path tracking of the flat rolling stock 2 from the sensor device 6 to the first roll stand 1. In the simplest case, the first waiting time corresponds to t1—see FIG 10 - the distance a1 from the sensor device 6 to the first roll stand 1, divided by the transport speed v1 of the flat rolling stock 2 in front of the first roll stand 1. If further roll stands are arranged between the sensor device 6 and the first roll stand 1, the first waiting time t1 may have to end an addition of several times can be determined, each time being characteristic of a specific section and characterized by the Transport speed of the flat rolling stock 2 in each section and the length of each section results.

In a step S15 and thus after the first waiting time t1 has elapsed, the control device 9 controls the first roll stand 1 in accordance with the control value A determined. Step S15 essentially corresponds to step S3 of FIG FIG 2 . As a result, the control device 9 outputs the control value A to the first rolling stand 1 , taking into account the tracking of the flat rolling stock 2 from the sensor device 6 to the first rolling stand 1 .

In a step S16, the control device 9 then waits for a second waiting time t2. The second waiting time t2 corresponds to the time that a specific section of the flat rolling stock 2 requires in order to reach the further sensor device 13 starting from the first roll stand 1 . The control device 9 thus essentially implements a path tracking of the flat rolling stock 2 from the first roll stand 1 to the further sensor device 13. In the simplest case t1—see again 10 - the second waiting time t2 corresponds to the distance a2 from the first rolling stand 1 to the further sensor device 13, divided by the transport speed v2 of the flat rolling stock 2 behind the first rolling stand 1. If further rolling stands are arranged between the first rolling stand 1 and the further sensor device 13, If necessary, the second waiting time t2 must be determined by adding several times, each time being characteristic of a specific section and resulting from the transport speed of the flat rolling stock 2 in the respective section and the length of the respective section.

In a step S17 and thus after the second waiting time t2 has elapsed, the control device 9 receives from the further sensor device 13 that further measured variable M′ which is detected by the further sensor device 13 at this point in time. In a step S18, the controller performs 9 calculates the model parameter k based on a comparison of the further measured variable M' and the expected value E of the material property E and thereby adapts the model 12. As a result, the control device 9 evaluates the further measured variable M' as part of the adaptation of the model 12 for a point in time which the control device 9 has determined taking into account the tracking of the flat rolling stock 2 from the first roll stand 1 to the further sensor device 13 .

The control device 9 carries out the steps S11 to S18 iteratively again and again, analogously to the steps S1 to S3. The above explanations for steps S1 to S3 can be applied analogously.

Furthermore, steps S11 to S18 and their sequence are implemented slightly differently in practice. For example, steps S11 to S18 can be instantiated multiple times. It is also possible to divide the sequence of steps S11 to S18 into two parts, which are executed in parallel. In this case, the first part comprises steps S11 to S15, and the second part comprises steps S16 to S18.

It is also possible to omit steps S14 and S16 as such. In this case, a direct, unsynchronized execution of the remaining steps S11 to S13, S15, S17 and S18 can take place. In this case, for example, the respective control value A determined in step S12 and the respective expected value E determined in step S13 can be temporarily buffered in a buffer (not shown). If necessary, the respective further measurement variable M′ recorded in step S17 can also be temporarily buffered in the intermediate memory. In this case, the respective control value A is assigned an execution time when it is stored. In this case, a realization time is assigned to the respective expected value E in an analogous manner. If necessary, a detection time can also be assigned to the respective further measured variable M′ will. In this case, when step S15 is executed, that stored control value A whose execution time has just been reached is output. In an analogous manner, when step S18 is executed, that stored expected value E is used whose time of use coincides with the current time. If necessary, stored control values A and stored expected values E can be interpolated in this context. If the further measured variables M' and their acquisition times are also stored, this also applies in an analogous manner to the further measured variables M'.

Irrespective of the specific implementation, however, it is important that the adaptation of the model 12 of step S18 acts on all subsequent executions of steps S12 and S13.

The type of drive value A can be determined as needed. What is decisive is that the activation of the first roll stand 1 with the activation value A influences the material properties of the flat rolling stock 2 . For example, it is as shown in the 12 and 13 It is possible for the control device 9 to determine a ratio of the upper peripheral speed vO to the lower peripheral speed vU as the control value A. In this case, therefore, asymmetrical rolling takes place, in which the two work rolls 3, 4 rotate at peripheral speeds vO, vU that differ from one another. The control value A can, for example, as shown in FIGS 12 and 13 as a factor by which the lower peripheral speed vU (or its target value vU*) must be multiplied when determining the upper peripheral speed vO (or its target value vO*).

As a rule, the ratio of the upper peripheral speed vO to the lower peripheral speed vU is between 0.5 and 2.0, in particular between 0.9 and 1.1. Furthermore, in generally irrelevant which of the two work rolls 3, 4 rotates faster than the other work roll 4, 3.

12 also shows an embodiment which is particularly easy to implement in terms of control technology. Specifically, as part of the design of 12 the upper work roll 3 is driven by an upper drive 14, while the lower work roll 4 is driven by a lower drive 15. The lower drive 15 is in accordance with the design 12 a different drive from the upper drive 14 . In this case, only the upper drive 14 and the lower drive 15 have to be given the corresponding desired values vO*, vU*.

In contrast, the upper work roll 3 and the lower work roll 4 in the embodiment of FIG 13 driven by a common drive 16. In this case, a gear 17 is arranged between the common drive 16 on the one hand and the upper work roll 3 and the lower work roll 4 on the other side. The transmission has an input shaft 18 on the one hand and an upper output shaft 19 and a lower output shaft 20 on the other. The input shaft 18 is non-rotatably connected to the common drive 16 . The upper output shaft 19 is non-rotatably connected to the upper work roll 3, the lower output shaft 20 to the lower work roll 4. The input shaft 18 acts both on the upper output shaft 19 and on the lower output shaft 20.

The gear 17 is designed in such a way that a ratio of a speed of the upper output shaft 19 to a speed of the lower output shaft 20 can be continuously adjusted by means of the gear 17 . For example, the transmission 17 can have a distribution block 21 on the one hand, in which the drive train is divided between the upper and lower work rolls 3, 4. Between the distribution block 21 and the upper work roll 3 can then be arranged an intermediate gear 22, by means of which a stepless variation the output-side speed relative to the input-side speed of the intermediate gear 22 is possible. Such intermediate gears 22 are well known to those skilled in the art. Examples are a planetary gear and a differential gear. As an alternative or in addition to an arrangement between the dividing block 21 and the upper working roll 3, an intermediate gear (not shown) can also be arranged between the dividing block 21 and the lower working roll 4.

14 shows another type of drive value A. According to 14 the control value A can be a temperature influencing of the upper work roll 3, which acts on the upper work roll 3 via a corresponding influencing device 23. For example, the upper work roll 3 can be cooled by spraying water on it. Alternatively or additionally, the control value A can be a temperature influence on the lower work roll 4 . For example, analogously to the upper work roll 3, the lower work roll 4 can be cooled by spraying on water via a corresponding influencing device 23'. Alternatively or additionally, the control value A can be a temperature influencing of the flat rolling stock 2 before rolling in the first roll stand 1 . For example, the flat rolling stock 2 can be heated, in particular inductively, via a corresponding influencing device 23″.

Above were in connection with the 1 to 14 explains the basic principle and various possible configurations of the present invention. As part of the 1 to 14 a reversing rolling mill was considered that has only a single roll stand 1, i.e. the first roll stand 1. Completely analogous configurations are also possible, however, if the rolling mill - with or without configuration as a reversing rolling mill - also has further roll stands, referred to below as second roll stands 24.

So it is, for example, as shown in the 15 to 20 possible that the rolling mill has a plurality of roll stands 1, 24 through which the rolling stock 2 passes sequentially one after the other. In this case, the rolling mill is designed as a multi-stand rolling train. However, the number of five rolling stands 1, 24 arranged one behind the other that is shown in each case is only purely exemplary. Also from the second roll stands 24 are in the 15 to 20 only the work rolls shown. As a rule, however, the second roll stands 24--similar to the first roll stand 1--have further rolls. Furthermore, in the 15 to 20 only the roll stands 1, 24, the rolling stock 2 and the sensor device 6 and optionally the further sensor device 13 are shown. The other components of the rolling mill - in particular the control device 9 - are available. The control device 9 usually acts on all roll stands 1, 24 of the rolling mill, even if in the 15 to 20 only the activation of the first roll stand 1 with the activation value A is shown.

The configurations of 15 to 20 are largely the same. However, they differ in the arrangement of the sensor device 6, in the arrangement of the second roll stands 24 relative to the sensor device 6 and to the first roll stand 1 and the presence or absence of the further sensor device 13.

Specifically, in the configurations of 15 and 16 the sensor device 6 is arranged behind the last rolling stand 1, 24 of the rolling train. When designing 15 the actuation value A—that is, the actuation value A determined taking into account the measured variable M—acts on the last roll stand 1 of the rolling train. In this case, the second roll stands 24 are not arranged between the sensor device 6 and the first roll stand 1 . When designing 16 On the other hand, the control value A - i.e. the control value A determined taking into account the measured variable M - acts on another roll stand 1 of the rolling train, for example the penultimate rolling stand of the rolling train arranged immediately upstream of the last rolling stand 24 of the rolling train. In this case, at least one of the second roll stands 24 - specifically at least the last roll stand 24 of the rolling train - is arranged between the sensor device 6 and the first roll stand 1 .

In the designs of 17 to 20 the sensor device 6 is arranged in front of the foremost roll stand 1, 24 of the rolling train. In the designs of 17 and 19 the actuation value A—that is, the actuation value A determined taking into account the measured variable M—acts on the foremost roll stand 1 of the rolling train. In this case, the second roll stands 24 are not arranged between the sensor device 6 and the first roll stand 1 . In the designs of 18 and 20 On the other hand, the control value A - i.e. the control value A determined taking into account the measured variable M - acts on another rolling stand 1 of the rolling train, for example on the rolling stand 1 immediately downstream of the foremost rolling stand 24 in the rolling train. In this case, at least one of the second rolling stands 24 - concretely at least the foremost rolling stand 24 of the rolling train - arranged between the sensor device 6 and the first rolling stand 1 .

In the designs of 19 and 20 the further sensor device 13 is also arranged behind the last rolling stand 1, 24 of the rolling train, so that the corresponding adaptation of the model 12 can take place. In the designs of 17 and 18 however, the further sensor device 13 is not present.

The configurations of 15 to 20 are not the only possible configurations of a multi-stand rolling train. For example, it is possible for several second roll stands 24 to be arranged between the first roll stand 1 and the sensor device 6 . In the extreme case, the sensor device 6 behind the last roll stand 24 of the rolling train be arranged and act on the foremost rolling stand 1 of the rolling train or, conversely, be arranged in front of the foremost rolling stand 24 of the rolling train and act on the last rolling stand 1 of the rolling train. It is also possible to provide several sensor devices 6 and/or several further sensor devices 13, for example to arrange one sensor device 6 and/or one further sensor device 13 in front of and/or behind each individual roll stand 1, 24 of the rolling train. It is also possible to make such arrangements between some roll stands 1, 24, but not in all roll stands 1, 24. It is also possible for the control device 9 to determine a plurality of control values A on the basis of the measured variable M of an individual sensor device, each of which is based on a different one first roll stand 1 act. It is up to the person skilled in the art to decide which configuration is specifically adopted.

Regardless of which configuration is actually taken, the mode of operation of the respective rolling mill 15 to 20 , as far as the present invention is concerned, is the same as described above in connection with FIGS 1 to 14 for the reversing mill with a single roll stand 1 - the first roll stand 1 - was explained.

The present invention has many advantages. In particular, a simple integration of the procedure according to the invention into the ongoing operation of the rolling mill is possible. In the case of electrical sheets and also other types of steel, an annealing treatment after cold rolling or between two cold rolling steps is often no longer necessary or only necessary to a limited extent. In the case of AHSS and martensitic and bainitic grades, the discontinuity of material properties caused by cooling in the cooling section of the hot rolling mill can be reduced or eliminated. If the action on the flat rolling stock 2 can be spatially resolved by means of the control value A in the width direction of the flat rolling stock 2 (this is the case in particular with a thermal influence), under Circumstances, several sensor devices 6 can also be arranged next to one another.

Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited by the disclosed examples and other variants can be derived therefrom by a person skilled in the art without departing from the protective scope of the invention as defined by the claims.

Reference List

1, 24

roll stands

2

flat rolling stock

3

upper stripper

4

lower stripper

5

reel

6, 13

sensor devices

7

excitation element

8a to 8d

sensor elements

9

control device

10

control program

11

program code

12

model

14 to 16

drives

17

transmission

18

input shaft

19, 20

output shafts

21

split block

22

intermediate gear

23, 23', 23"

influencing devices

A

control value

a1, a2

distances

d1, d2

thick

E

expected value

f

rolling force

IA, IW

streams

Ia to Id

sensor signals

k

model parameters

M, M'

metrics

S1 to S18

steps

t1, t2

waiting times

T

temperature

v, v1, v2

transport speeds

vO, vU

peripheral speeds

vO*, vU*

setpoints

x

transport direction

Claims (16)

1. Rolling mill having a first rolling stand (1) for rolling a flat rolled product (2) composed of metal,

   - wherein a sensor device (6), by means of which at least one measured variable (M) characteristic of a material property of the flat rolled product (2) can be detected, is arranged upstream and/or downstream of the first rolling stand (1),

   - wherein the sensor device (6) is connected to a control device (9) for the rolling mill in order to transfer the detected measured variable (M),

   - wherein the control device (9) is designed in such a way that it takes account of the transferred measured variable (M) in the context of determining a control value (A) for the first rolling stand (1),

   - wherein the control of the first rolling stand (1) with the control value (A) influences the material property of the flat rolled product (2),

   - wherein the first rolling stand (1) has an upper working roll (3) and a lower working roll (4),

   characterized
   in that the control device (9) is designed in such a way that the control value (A) determined taking into account the measured variable (M) is a ratio of an upper peripheral speed (vO) at which the upper working roll (3) rotates to a lower peripheral speed (vU) at which the lower working roll (4) rotates.
2. Rolling mill according to Claim 1,
   characterized
   in that the rolling mill has at least one second rolling stand (24) and in that the second rolling stands (24) are not arranged between the sensor device (6) and the first rolling stand (1).
3. Rolling mill according to Claim 1,
   characterized
   in that the rolling mill has at least one second rolling stand (24) and in that at least one of the second rolling stands (24) is arranged between the sensor device (6) and the first rolling stand (1).
4. Rolling mill according to Claim 1,
   characterized
   in that the control device (9) is designed in such a way that it determines the ratio of the upper peripheral speed (vO) to the lower peripheral speed (vU) in such a way that it is between 0.5 and 2.0, in particular between 0.9 and 1.1.
5. Rolling mill according to Claim 1 or 4,
   characterized
   in that the upper working roll (3) is driven by an upper drive (14) and the lower working roll (4) is driven by a lower drive (15), which is different from the upper drive (14).
6. Rolling mill according to Claim 1 or 4,
   characterized
   in that the upper working roll (3) and the lower working roll (4) are driven by a common drive (16) and in that a transmission (17), by means of which a ratio of a speed of an upper output shaft (19) of the transmission (17), said shaft being connected for conjoint rotation to the upper working roll (3), to a speed of a lower output shaft (20) of the transmission (17), said shaft being connected for conjoint rotation to the lower working roll (4), can be continuously adjusted, is arranged between the common drive (16) on one side and the upper working roll (3) and the lower working roll (4) on the other side.
7. Rolling mill according to any of the above claims,
   characterized
   in that the first rolling stand (1) has an upper working roll (3) and a lower working roll (4) and in that the control device (9) is designed in such a way that the control value (A) determined taking into account the measured variable (M) is a temperature modification of the upper working roll (3) and/or of the lower working roll (4) of the first rolling stand (1) and/or of the flat rolled product (2) before rolling in the first rolling stand (1).
8. Rolling mill according to any of the above claims,
   characterized
   in that the sensor device (6) is arranged upstream of the first rolling stand (1) and in that the control device (9) is designed in such a way that it outputs to the first rolling stand (1) the control value (A), determined taking into account the measured variable (M), taking into account tracking of the flat rolled product (2) from the sensor device (6) to the first rolling stand (1).
9. Rolling mill according to Claim 8,
   characterized

   - in that the control device (9) comprises a model (12), by means of which the control device (9) determines the control value (A) for the first rolling stand (1) taking into account the measured variable (M), and, taking into account the control value (A) determined taking into account the measured variable (M), furthermore determines an expected value (E) for the material property of the flat rolled product (2) after rolling in the first rolling stand (1),

   - in that a further sensor device (13), by means of which at least one further measured variable (M') characteristic of the material property of the flat rolled product (2) after rolling in the first rolling stand (1) can be detected, is arranged downstream of the first rolling stand (1),

   - in that the further sensor device (13) is connected to the control device (9) to transfer the detected further measured variable (M'),

   - in that the control device (9) is designed in such a way that it uses the further measured variable (M') for a point in time which the control device (9) determines taking into account tracking of the flat rolled product (2) from the first rolling stand (1) to the further sensor device (13), and

   - in that the control device (9) is designed in such a way that it adapts the model (12) on the basis of a comparison of the further measured variable (M') and the expected value (E) of the material property.
10. Rolling mill according to any of the above claims,
    characterized
    in that the control device (9) is designed in such a way that, in determining the control value (A), it takes into account the temperature (T) of the flat rolled product (2) before the rolling of the flat rolled product (2) in the first rolling stand (1) and/or the rolling force (F) during the rolling of the flat rolled product (2) in the first rolling stand (1) and/or the pass reduction during the rolling of the flat rolled product (2) in the first rolling stand (1) in addition to the transferred measured variable (M).
11. Rolling mill according to any of the above claims,
    characterized

    - in that the sensor device (9) comprises an excitation element (7) and a first sensor element (8a),

    - in that a base signal is excited in the flat rolled product (2) by means of the excitation element (7),

    - in that a first sensor signal (Ia) based on the excited base signal is detected by means of the first sensor element (8a), and

    - in that the sensor device (6) determines the transferred measured variable (M) taking into account the first sensor signal (Ia) or in that the transferred measured variable (M) comprises the first sensor signal (Ia).
12. Rolling mill according to Claim 11,
    characterized

    - in that the sensor device (6) additionally comprises a number of second sensor elements (8b to 8d),

    - in that when viewed in the transport direction (x) from the first sensor element (8a), the respective second sensor element (8b to 8d) is arranged upstream or downstream of the first sensor element (8a) and/or laterally offset,

    - in that a respective second sensor signal (Ib to Id) based on the excited base signal and of the same kind as the first sensor signal (Ia) is detected by means of the respective second sensor element (8b to 8d), and

    - in that the sensor device (6) determines the transferred measured variable (M) while also taking into account the respective second sensor signal (Ib to Id) or in that the transferred measured variable (M) also comprises the respective second sensor signal (Ib to Id).
13. Rolling mill according to Claim 11 or 12,
    characterized
    in that the base signal is an eddy current (IW) or a sound signal, in particular an ultrasound signal.
14. Rolling mill according to Claim 11, 12 or 13,
    characterized
    in that a connecting line from the excitation element (7) to the first sensor element (8a) runs parallel to the transport direction (x).
15. Rolling mill according to any of the above claims,
    characterized
    in that the material property is an electromagnetic property or a mechanical property of the rolled product (2).
16. Rolling mill according to any of the above claims,
    characterized
    in that the rolling mill is a cold rolling mill.

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