EP3858503A1 - Rolling mill with material property dependent rolling - Google Patents

Abstract

A rolling mill has a first roll stand (1) in which a flat rolling stock (2) made of metal is rolled. A sensor device (6) is arranged in front of and / or behind the first roll stand (1), by means of which at least one measured variable (M) characteristic of a material property of the flat rolling stock (2) is detected. The material property can in particular be an electromagnetic property or a mechanical property of the rolling stock (2). The sensor device (6) transmits the measured variable (M) to a control device (9) for the rolling mill. The control device (9) takes the transmitted measured variable (M) into account when determining a control value (A) for the first roll stand (1). The activation of the first roll stand (1) with the activation value (A) influences the material properties of the flat rolling stock (2).

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.

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

• wherein a sensor device is arranged in front of and / or behind the first roll stand,
• wherein the sensor device for transmitting the detected measured variable is connected to a control device for the rolling mill,
• wherein the control device is designed in such a way that it takes into account the transmitted measured variable in the context of determining a control value for the first roll stand.

The term "first roll stand" is not meant in the context of the present invention in such a way that the roll mill necessarily has several roll stands and the first roll stand is the foremost roll stand through which the flat rolling stock passes first. Rather, it should initially also include the case that the rolling mill only has the first rolling stand. In this case, only the first roll stand is available. Furthermore, even in the event that the rolling mill has several rolling stands, the term “first rolling stand” only serves to distinguish it from the other rolling stands of the rolling mill. However, no order is intended to 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 passes 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 of the roll stands A. to be D while the other stands are second stands.

In the manufacture of a flat rolled stock, the aim is to adjust the geometric properties of the flat rolled stock, that is to say in particular its width and its thickness, with the greatest possible precision. The same also applies to the profile or the contour. The flatness should also be maintained. In addition to these and possibly other geometric properties, material properties of the flat rolled stock should also be set. Material properties are properties that the flat rolled stock should have during later use, for example a certain yield point, a certain material hardness or a certain magnetizability. Material properties are properties that the material has regardless of its specific current state (such as temperature) and also regardless of its geometric properties. The cause of certain material properties is - in addition to the material as such - the grain structure of the metal.

The setting of material properties can - at least partially - take place during the rolling of the flat rolled stock. Often, however, there remains a difference between the actual value of a material property and a desired target value. In this case, it is necessary to thermally treat the flat rolled stock after hot rolling. This is particularly true when a certain so-called Goss texture is to be set in the rolling stock. Similar problems also arise with certain steels, in particular with AHSS (= advanced high strength steel) and martensitic and bainitic grades. In the case of a thermal treatment, the rolling stock can be suitably cooled in a cooling section, for example after hot rolling, or can be treated in an annealing furnace as part of cold rolling, in order to set material properties. This treatment can be an alternative after cold rolling or between two cold rolling steps.

State of the art

From the technical article " Forming technology for electromobility "by Gerhard Hirt et al., Accessed on January 21, 2020 At https://publications.rwth-aachen.de/record/762556/files/ 762556.pdf, 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 asymmetrical rolling, the peripheral speed of an upper and a lower work roll of a rolling stand differ from one another. During the rolling process, shear forces act on the flat rolling stock in the direction of transport. The crystal orientation is rearranged due to the shear forces.

Summary of the invention

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

The object is achieved by a rolling mill with the features of claim 1. Advantageous configurations of the rolling mill are the subject of dependent claims 2 to 17.

According to the invention, in a rolling mill of the type mentioned, the sensor device is designed such that at least one measured variable characteristic of a material property of the flat rolled stock can be detected by means of the sensor device, and the control of the first roll stand with the control value influences the material property of the flat rolled stock.

A measured variable is therefore recorded, which is used to directly determine the corresponding material properties of the flat rolled stock Time of measurement can be determined. So there is 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 measurement” is not intended to imply that the material property also changes automatically and continuously over the course of time due to the change in the condition of the flat rolled stock, for example its temperature. The material property can, however, be set to a different value by appropriate treatment of the rolling stock - for example by rolling in the first roll stand or rolling in another roll stand or by thermal treatment at a later point in time.

It is possible for the rolling mill to have exclusively said first roll stand and consequently only a single roll stand. In this case, the sensor device is automatically arranged 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 roll stand of a multi-stand rolling mill and the control value determined by the control device, taking the measured variable into account, acts on the foremost roll stand or, conversely, the sensor arrangement is arranged behind the last roll stand of a multi-stand rolling mill and the the control value determined by the control device taking into account the measured variable for the last roll stand works. This configuration is also implemented, for example, when the sensor arrangement is arranged between two roll stands of a multi-stand rolling mill and the control value determined by the control device, taking the measured variable into account, acts on one of these two roll stands, or the control device determines two such control values, one of which is dependent on each one of these two roll stands works.

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 embodiment is implemented, for example, when the sensor device is arranged in front of the foremost roll stand of a multi-stand rolling mill and the control value determined by the control device, taking the measured variable into account, acts on a different than the foremost roll stand or, conversely, the sensor arrangement is arranged behind the last roll stand of a multi-stand rolling mill and the control value determined by the control device, taking the measured variable into account, acts on a roll stand other than the last.

Combinations of these approaches are of course also possible. For example, the sensor device can be arranged in front of the foremost roll stand of the multi-stand rolling mill and the control device can also determine several control values, taking into account the measured variable, one of which acts on the foremost roll stand and another on another roll stand. Likewise, conversely, the sensor arrangement can be arranged behind the last roll stand of the multi-stand rolling mill and the control device can also determine several control values taking into account the measured variable, one of which acts on the last roll stand and another on another roll stand.

The first roll stand has an upper work roll and a lower work roll. It is possible that the control device is designed such 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. This procedure can be advantageous, for example, for setting electrical or magnetic properties of the flat rolled stock. However, it can also be used to set the mechanical properties of the flat rolled stock.

The control device is preferably designed such 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 achieve circumferential speeds that differ from one another, it is possible for the upper work roll to be driven by an upper drive and 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 achieved by setting the two drives accordingly to different speeds.

Alternatively, it is possible that the upper work roll and the lower work roll are driven by a common drive. In this case, a transmission 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 transmission connected in a rotationally fixed manner to the upper work roll versus a speed of a the lower work roll rotatably connected lower output shaft of the transmission is continuously adjustable.

As an alternative or in addition to setting a ratio of the circumferential speeds to one another, it is possible that the control device is 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 is before rolling in the first roll stand. For example, cooling can be brought about by spraying on water or heating can be brought about by means of induction heating.

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

The control device preferably comprises 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 rolled stock after rolling in the first roll stand, taking into account the control value determined taking into account the measured variable. 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 further sensor device is connected to the control device in order to transmit the detected further measured variable. Finally, the control device is preferably designed in such a way that it controls the further The measured variable is used for a point in time that the control device determines, taking into account a path of the flat rolling stock from the first roll stand to the further sensor device, and adapts the model based on a comparison of the further measured variable and the expected value of the material property. With this approach, the model can gradually be better and better adapted to the actual behavior of the flat rolled stock.

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

In a preferred embodiment, the sensor device comprises 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 measured variable taking into account the first sensor signal. Alternatively, it is possible for the transmitted measured variable to include the first sensor signal.

In individual cases it may be possible that only the first sensor signal is recorded. As a rule, however, the sensor device additionally comprises 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 ultrasound 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.

Hot rolling can be carried out in individual cases. As a rule, however, cold rolling is carried out. The rolling mill is therefore 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 properties, 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 conjunction with the drawings. Here show 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 ,

FIGS. 3 and 4

Side views of FIG 3 at two points in time,

FIG 5

a flow chart,

FIG 6

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

FIGS. 7 and 8

Side views of FIG 6 at two points in time,

FIGS. 9 and 10

each a further rolling mill with a first rolling stand,

FIG 11

a flow chart,

FIGS. 12 and 13

Drive structures for work rolls,

FIG 14

a roll stand and temperature influences and

FIGS 15 to 20

various designs of rolling mills.

Description of the embodiments

According to FIG 1 has a rolling mill - like every rolling mill - at least one first roll stand 1. The first roll stand 1 is used to roll 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 rolled stock can in particular be an electrical sheet with a relatively high proportion of silicon (mostly 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 a matter of 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 further FIG. As a rule, however, the first roll stand 1 also has additional rolls, for example in the case of a four-high stand in addition to the work rolls 3, 4 back-up rolls and in the case of a six-high stand in addition to the work rolls 3, 4 and the back-up rolls, intermediate rolls that are between the work rolls 3, 4 and the backup rolls are arranged. 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 speed vO, vU are greater than 0.

According to the representation in FIG 1 the rolling mill is designed as a reversing mill. It therefore has a reel 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 a reversing mill, the terms "in front of" and "behind" are therefore only defined during a respective rolling pass and are reversed with the 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 measured variable M detected is characteristic of a material property of the flat rolled stock 2. Examples of such properties are the electrical conductivity, the permeability number and the magnetic saturation or, in general, an electromagnetic property of the rolling stock 2. Further examples of material properties are the yield strength, the yield strength, the elongation at break or, in general, 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.

In connection with the FIGS. 2 to 4 a possible embodiment 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 FIGS. 2 to 4 the sensor device 6 comprises 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 can be shown in FIG FIG 3 and 4th be designed as a coil to which an excitation current IA is applied intermittently and thereby generates an eddy current IW in the rolling stock 2 as a base signal. FIG 3 shows the sensor device 4 at a point in time at which the excitation element 7 is subjected to the excitation current IA.

The sensor device 6 furthermore comprises a first sensor element 8a. A first sensor signal Ia is detected by means of the first sensor element 8a. The acquisition of the first sensor signal Ia takes place after the excitation of the base signal, that is to say at a different, later point in time. At this later point in time, no base signal is usually excited. However, a previously excited base signal has not yet completely subsided. The first sensor signal Ia is based on the excited base signal. For example, the first sensor element 8a can according to the illustration in FIGS FIG 3 and 4th 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 FIGS. 2 to 4 shown as a different element from the excitation element 7. This configuration is the normal case. In this case, the first sensor element 8a is arranged behind the excitation element 7, as seen 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 configuration can in particular then be possible be when a period between the excitation of the base signal and the detection of the excited base signal is sufficiently small.

The sensor device 6 is shown in FIG 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 measured 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 that the sensor device 6 first evaluates the first sensor signal Ia (and possibly further signals) to determine the measured variable M and that the result of this evaluation is 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 elements from the first sensor element 8a (and generally also from the excitation element 7). As 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 the 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. A corresponding evaluation of the sensor signals Ia to Id takes place in this case by the control device 9. Alternatively, an evaluation of the sensor signals Ia to Id (completely or partially) can already be 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 as seen 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 on the basis of 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 relate the first sensor signal Ia 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 as seen from the first sensor element 8a in the transport direction x. An arrangement behind the first sensor element 8a is the rule in this case. Even with an arrangement of the second sensor element 8d in front of or behind the first sensor element 8a, the sensor device 6 can relate the first sensor signal Ia to the second sensor signal 8d and thereby the measured variable M determine. The measured variable M can also in this case can be determined in particular on the basis of the difference or the quotient of the sensor signals Ia, Id.

The control device 9 takes according to FIG 5 in a step S1 the measured variable M transmitted to it. In a step S2, the control device 9 determines a control value A for the first roll stand 1. As shown in FIG FIG 5 When determining the control value A, the control device 9 takes into account at least the transmitted measured variable M. When determining the control value A, the control device 9 also often takes into account further variable data such as the temperature T of the flat rolling stock 2 before rolling in the first roll stand 1 and / or the rolling force F when rolling the flat rolling stock 2 in the first roll stand 1 and / or the decrease in the pass 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 decrease, i.e. the ratio of the outlet-side thickness d2 of the flat rolling stock 2 to the inlet-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 in the context of the evaluation of 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 in accordance with the control value A determined.

The control device 9 iteratively carries out steps S1 to S3 again and again. A time constant with which the repetition takes place is mostly 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 follows the procedure of FIG 5 executes. The control device 9 is still according to the representation in FIG 1 usually designed as a software-programmable control device. The control device 9 is programmed with a control program 10 in this case. The control program 10 comprises program code 11 which can be processed by the control device 9. During operation, the control device 9 processes the program code 11. The processing of the program code 11 by the control device 9 has the effect that the control device 9 is designed accordingly.

The above in connection with the FIG 1 to 5 Refinements explained in which the base signal is an eddy current IW and thus an electrical variable. These configurations are particularly useful when the measured variable M is intended to be characteristic of an electrical or magnetic material property. However, the configurations can also enable conclusions to be drawn about mechanical material properties.

In connection with the FIGS. 6 to 8 another embodiment explained. the FIGS. 6 to 8 show here to the FIGS. 2 to 4 completely analogous configurations. The difference is that the FIGS. 6 to 8 the excitation element 7 emits a sound signal, in particular an ultrasound signal. Correspondingly, the sensor elements 8a to 8d are also designed to detect a corresponding sound signal. The remarks on the FIGS. 2 to 4 applicable in an analogous manner.

FIG 9 FIG. 8 shows a modification of the rolling mill of FIG FIG 1 . The difference is that in the design of the rolling mill according to FIG 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 remarks relating to FIG FIG 1 and also the explanations on the FIGS. 2 to 8 - For example, the design of the control device 9 as software-programmable - can still be used. As part of the design according to FIG 9 is it particularly 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 of the flat rolling stock 2 from the sensor device 6 to the first roll stand 1 to the first roll stand 1. The details of this are explained in connection with a further embodiment which is described below in connection with FIG 10 is explained.

FIG 10 is based on FIG 9 . As with FIG 9 is therefore in accordance with the design FIG 10 the sensor device 6 is arranged in front of the first roll stand 1. The control device 9 comprises a model 12, for example due to the execution of the program code 11. 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 recorded further measured variable M ′ is characteristic of the material property of the flat rolled stock 2 as it is present in the first roll stand 1 after rolling. The further measured variable M 'is therefore characteristic of the same material property as the measured variable M and is therefore similar in approach to the measured variable M. The difference is that the measured variable M is characteristic of the material property of the flat rolling stock 2 before rolling in the first roll stand 1 , 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 further sensor device 13 is also connected to the control device 9 for the rolling mill. Due to the connection of the further sensor device 13 to the control device 9, the detected further measured variable M ′ can in particular be transmitted to the control device 9.

The operation of the rolling mill of FIG 10 is used below in conjunction with FIG 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 shows FIG 11 also the operation of the rolling mill of FIG 9 .

According to FIG 11 the control device 9 receives the measured variable M transmitted to it in a step S11. 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 step S12 corresponds essentially to the step S2 of FIG FIG 2 . The difference is that the control device 9 determines the control value A by means of the model 12 in step S12. A model parameter k is included in the determination of the activation value A, among other things.

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 this control value A into account - that is, the control value A determined in step S12 .

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 certain section of the flat rolling stock 2 needs to reach the first roll stand 1 starting from the sensor device 6. Essentially, the control device 9 thus 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 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 go through an addition of several times can be determined, each time being characteristic of a specific section and being divided by the Transport speed of the flat rolling stock 2 in the respective section and the length of the respective 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 from FIG FIG 2 . As a result, the control device 9 outputs the control value A to the first roll stand 1, taking into account the tracking of the flat rolling stock 2 from the sensor device 6 to the first roll 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 needs to reach the further sensor device 13 starting from the first roll stand 1. Essentially, the control device 9 thus 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 FIG 10 - the second waiting time t2 corresponds to the distance a2 from the first roll stand 1 to the further sensor device 13, divided by the transport speed v2 of the flat rolling stock 2 behind the first roll stand 1. If further roll stands are arranged between the first roll stand 1 and the further sensor device 13, the second waiting time t2 may have to be determined by adding several times, each time being characteristic of a specific section and resulting from the transport speed of the flat rolled 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 'that is detected by the further sensor device 13 at this point in time. In a step S18, the control device executes 9 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 utilizes the further measured variable M' for a point in time as part of the adaptation of the model 12 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 steps S11 to S18 iteratively over and over again, analogously to steps S1 to S3. The above remarks on 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 executed multiple times instantiated. It is also possible to divide the sequence of steps S11 to S18 into two parts that are carried out 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 measured variable M 'recorded in step S17 can also be temporarily buffered in the intermediate memory. In this case, an execution time is assigned to the respective control value A during storage. In an analogous manner, in this case the respective expected value E is assigned a recovery time. If necessary, an acquisition time can also be assigned to the respective further measured variable M ' become. In this case, when step S15 is executed, that stored control value A is output whose execution time has just been reached. In an analogous manner, when step S18 is carried out, that stored expected value E is used whose point of 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'.

Regardless of the specific implementation, it is important that the adaptation of the model 12 of step S18 affects all subsequent executions of steps S12 and S13.

The type of control value A can be determined as required. It is decisive that the activation of the first roll stand 1 with the activation value A influences the material properties of the flat rolled stock 2. For example, it is as shown in FIGS. 12 and 13 It is possible for the control device 9 to determine a ratio of the upper circumferential speed vO to the lower circumferential 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 circumferential speeds vO, vU which differ from one another. The control value A can, for example, according to the representation in FIG FIGS. 12 and 13 as a factor with which the lower circumferential speed vU (or its target value vU *) must be multiplied, are included in the determination of the upper circumferential 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 It is generally irrelevant which of the two work rolls 3, 4 rotates faster than the other work roll 4, 3.

FIG 12 furthermore shows an embodiment which is particularly easy to implement in terms of control technology. Specifically, as part of the design of FIG 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 according to the embodiment FIG 12 a drive different from the upper drive 14. In this case, only the upper drive 14 and the lower drive 15 have to be given the corresponding setpoint values vO *, vU *.

In contrast, the upper work roll 3 and the lower work roll 4 in the embodiment of FIG 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, on the one hand, an input shaft 18 and, on the other hand, an upper output shaft 19 and a lower output shaft 20. The input shaft 18 is connected to the common drive 16 in a rotationally fixed manner. The upper output shaft 19 is connected in a rotationally fixed manner 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 transmission 17 is designed such 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 transmission 17. For example, the transmission 17 can on the one hand have a splitting block 21 in which the drive train is split between the upper and lower work rolls 3, 4. An intermediate gear 22 can then be arranged between the dividing block 21 and the upper work roll 3, 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 work roll 3, an intermediate gear (not shown) can also be arranged between the dividing block 21 and the lower work roll 4.

FIG 14 shows another kind of the drive value A. According to FIG FIG 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. As an alternative or in addition, the control value A can influence the temperature of 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 '. As an alternative or in addition, the control value A can influence the temperature of the flat rolling stock 2 before rolling in the first roll stand 1. For example, the flat rolling stock 2 can be heated via a corresponding influencing device 23 ″, in particular inductive heating.

The foregoing in connection with the FIGS. 1 to 14 the basic principle and various possible configurations of the present invention are explained. As part of the FIGS. 1 to 14 A reversing mill was considered which 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 a reversing mill configuration - additionally has further roll stands, hereinafter referred to as second roll stands 24.

So it is, for example, as shown in FIGS 15 to 20 It is possible for the rolling mill to have a plurality of rolling stands 1, 24 through which the rolling stock 2 traverses sequentially one after the other. In this case, the rolling mill is designed as a multi-stand rolling train. The number of a total of five roll stands 1, 24 arranged one behind the other is shown, however, only by way of example. Also of the second roll stands 24 are in the FIGS 15 to 20 only the work rolls shown. As a rule, however, the second roll stands 24 - analogously to the first roll stand 1 - have further rollers. Furthermore, in the FIGS 15 to 20 only the rolling stands 1, 24, the rolling stock 2 and the sensor device 6 and possibly the further sensor device 13 are shown. However, the other components of the rolling mill - in particular the control device 9 - are present. The control device 9 also acts as a rule on all roll stands 1, 24 of the rolling mill, even if in the FIGS 15 to 20 only the control of the first roll stand 1 with the control value A is shown.

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

Specifically, the design of the FIGS 15 and 16 the sensor device 6 is arranged behind the last roll stand 1, 24 of the rolling train. When designing FIG 15 The control value A - that is, the control value A determined taking into account the measured variable M - acts on the last rolling 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 FIG 16 on the other hand, the control value A - that is, the control value A determined taking into account the measured variable M - acts on another roll stand 1 of the rolling train, for example that penultimate roll stand of the rolling train immediately upstream of the last roll 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 the FIGS. 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 the FIG 17 and 19th The control value A - that is, the control 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 the FIG 18 and 20th on the other hand, the control value A - that is, the control value A determined taking the measured variable M into account - acts on another roll stand 1 of the rolling train, for example on the roll stand 1 immediately downstream of the foremost roll stand 24 of the rolling train. In this case, at least one of the second roll stands 24 - specifically, at least the foremost roll stand 24 of the rolling train - arranged between the sensor device 6 and the first roll stand 1.

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

The refinements of the FIGS 15 to 20 are not the only possible configurations of a multi-stand rolling mill. For example, it is possible for a plurality of 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 can be behind the last roll stand 24 of the rolling train be arranged and act on the foremost roll stand 1 of the rolling train or, conversely, be arranged in front of the foremost roll stand 24 of the rolling train and act on the last roll 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 a sensor device 6 and / or a 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 for all roll stands 1, 24. It is also possible for the control device 9 to determine several control values A based on the measured variable M of an individual sensor device, each of which refers to a different one first roll stand 1 act. It is up to the person skilled in the art to decide which configuration is actually adopted.

Regardless of which configuration is actually taken, the mode of operation of the respective rolling mill is the FIGS 15 to 20 as far as the present invention is concerned, the same as described above in connection with the 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, the procedure according to the invention can be easily integrated into the ongoing operation of the rolling mill. In the case of electrical steel sheets and other types of steel, annealing treatment after cold rolling or between two cold rolling steps is often no longer necessary or only necessary to a limited extent. With AHSS and with martensitic and bainitic grades, the linearity of material properties, which is caused by the 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 take place in a spatially resolved manner in the width direction of the flat rolling stock 2 by means of the control value A (this is the case in particular in the case of a thermal influence), under Under certain circumstances, several sensor devices 6 can also be arranged next to one another.

Although the invention has been illustrated and described in more detail by the preferred exemplary embodiment, the invention is not restricted by the disclosed examples and other variants can be derived therefrom by the person skilled in the art without departing from the scope of protection of the invention.

List of reference symbols

1, 24

Roll stands

2

flat rolling stock

3

upper work roll

4th

lower work roll

5

reel

6, 13

Sensor devices

7th

Excitation element

8a to 8d

Sensor elements

9

Control device

10

Control program

11

Program code

12th

model

14 to 16

Drives

17th

transmission

18th

Input shaft

19, 20

Output shafts

21

Splitting block

22nd

Intermediate gear

23, 23 ', 23 "

Influencing devices

A.

Control value

a1, a2

distances

d1, d2

Thick

E.

Expected value

F.

Rolling force

IA, IW

Currents

Ia to Id

Sensor signals

k

Model parameters

M, M '

Measurands

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 (17)

Rolling mill with a first roll stand (1) for rolling a flat rolling stock (2) made of metal, - wherein a sensor device (6) is arranged in front of and / or behind the first roll stand (1), by means of which at least one measured variable (M) characteristic of a material property of the flat rolling stock (2) can be detected, - wherein the sensor device (6) for transmitting the detected measured variable (M) is connected to a control device (9) for the rolling mill, - the control device (9) being designed in such a way that it takes into account the transmitted measured variable (M) in the context of determining a control value (A) for the first roll stand (1), - wherein the control of the first roll stand (1) with the control value (A) influences the material properties of the flat rolling stock (2). Rolling mill according to claim 1,
characterized,
that the rolling mill has at least one second roll stand (24) and that the second roll stands (24) are not arranged between the sensor device (6) and the first roll stand (1). Rolling mill according to claim 1,
characterized,
that the rolling mill has at least one second roll stand (24) and that at least one of the second roll stands (24) is arranged between the sensor device (6) and the first roll stand (1). Rolling mill according to claim 1, 2 or 3,
characterized,
that the first roll stand (1) has an upper work roll (3) and a lower work roll (4) and that the control device (9) is designed such that the the control value (A) determined for the measured variable (M) is a ratio of an upper peripheral speed (vO), with which the upper work roll (3) rotates, to a lower peripheral speed (vU), with which the lower work roll (4) rotates. Rolling mill according to claim 4,
characterized,
that the control device (9) is designed such 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 . Rolling mill according to claim 4 or 5,
characterized,
that the upper work roll (3) is driven by an upper drive (14) and the lower work roll (4) is driven by a lower drive (15) different from the upper drive (14). Rolling mill according to claim 4 or 5,
characterized,
that the upper work roll (3) and the lower work roll (4) are driven by a common drive (16) and that between the common drive (16) on one side and the upper work roll (3) and the lower work roll (4) on the other side a gear (17) is arranged, by means of which a ratio of a speed of an upper output shaft (19) of the gear (17) connected to the upper work roll (3) in a rotationally fixed manner to a speed of a rotationally fixed to the lower work roll (4) connected lower output shaft (20) of the transmission (17) is continuously adjustable. Rolling mill according to one of the above claims,
characterized,
that the first roll stand (1) has an upper work roll (3) and has a lower work roll (4) and that the control device (9) is designed in such a way that the control value (A) determined taking into account the measured variable (M) influences the temperature of the upper work roll (3) and / or the lower work roll (4) of the first roll stand (1) and / or the flat rolling stock (2) before rolling in the first roll stand (1). Rolling mill according to one of the above claims,
characterized,
that the sensor device (6) is arranged in front of the first roll stand (1) and that the control device (9) is designed in such a way that it receives the control value (A) determined taking into account the measured variable (M), taking into account the path of the flat rolling stock (2 ) outputs from the sensor device (6) to the first roll stand (1) on the first roll stand (1). Rolling mill according to claim 9,
characterized, - 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 roll stand (1) taking into account the measured variable (M) and also taking into account the measured variable (M) determined control value (A) determines an expected value (E) for the material property of the flat rolling stock (2) after rolling in the first roll stand (1), - That behind the first roll stand (1) a further sensor device (13) is arranged, by means of which at least one further measured variable (M ') characteristic of the material properties of the flat rolling stock (2) after rolling in the first roll stand (1) can be detected , - that the further sensor device (13) is connected to the control device (9) for transmitting the detected further measured variable (M '), - That the control device (9) is designed in such a way that it utilizes the further measured variable (M ') for a point in time, which the control device (9) determines taking into account a path of the flat rolling stock (2) from the first roll stand (1) to the further sensor device (13), and - 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. Rolling mill according to one of the above claims,
characterized,
that the control device (9) is designed in such a way that, when determining the control value (A), in addition to the transmitted measured variable (M), the temperature (T) of the flat rolling stock (2) before the rolling of the flat rolling stock (2) in the first roll stand (1) and / or the rolling force (F) when rolling the flat rolling stock (2) in the first roll stand (1) and / or the decrease in stitches when rolling the flat rolling stock (2) in the first roll stand (1). Rolling mill according to one of the above claims,
characterized, - that the sensor device (9) comprises an excitation element (7) and a first sensor element (8a), - that a base signal is excited by means of the excitation element (7) in the flat rolling stock (2), - that a first sensor signal (Ia) based on the excited base signal is detected by means of the first sensor element (8a), and - that the sensor device (6) determines the transmitted measured variable (M) taking into account the first sensor signal (Ia) or that the transmitted measured variable (M) includes the first sensor signal (Ia). Rolling mill according to claim 12,
characterized, - that the sensor device (6) additionally comprises a number of second sensor elements (8b to 8d), - that , viewed from the first sensor element (8a) in the transport direction (x), the respective second sensor element (8b to 8d) is arranged in front of or behind the first sensor element (8a) and / or laterally offset, - that by means of the respective second sensor element (8b to 8d) a respective second sensor signal (Ib to Id) based on the excited base signal and similar to the first sensor signal (Ia) is detected and - that the sensor device (6) determines the transmitted measured variable (M) taking into account the respective second sensor signal (Ib to Id) or that the transmitted measured variable (M) also includes the respective second sensor signal (Ib to Id). Rolling mill according to claim 12 or 13,
characterized,
that the base signal is an eddy current (IW) or an acoustic signal, in particular an ultrasonic signal. Rolling mill according to claim 12, 13 or 14,
characterized,
that a connecting line from the excitation element (7) to the first sensor element (8a) runs parallel to the transport direction (x). Rolling mill according to one of the above claims,
characterized,
that the material property is an electromagnetic property or a mechanical property of the rolling stock (2). Rolling mill according to one of the above claims,
characterized,
that the rolling mill is a cold rolling mill.

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