DE102019217966A1 - Setting a run-out temperature of a metal strip running out of a rolling train - Google Patents

Abstract

The invention relates to a method for setting an outlet temperature of a metal strip (2) exiting from an at least two-stand rolling train (3), the outlet temperature being determined by means of a process model, taking into account a relationship between strip forming and / or a cooling rate of the metal strip (2) by at least one Cooling medium and by at least one fixed rolling train component and / or a rolling speed in a last roll stand (7) of the rolling train (3) on the one hand and the outlet temperature on the other. In order to create a process that can be implemented more cost-effectively, after the process model has been used to determine an intervention-related deviation in the strip deformation and / or the rolling speed in the last roll stand (7) from the setting values contained in the context for the strip deformation and / or the rolling speed in the last roll stand (7) by means of the process model a deviation of the outlet temperature associated with the intervention-related deviation from a setpoint temperature contained in the context is determined, the strip deformation in the last roll stand (7) and in one or more upstream roll stands (5, 6) of the rolling train (3) is changed by means of the process model depending on the deviation of the outlet temperature in such a way that the outlet temperature corresponds to the target temperature.

Description

The invention relates to a method and a control device for setting an exit temperature of a metal strip exiting from an at least two-stand rolling train. In addition, the invention relates to a rolling plant for rolling a metal strip, having at least one at least two-stand rolling train and at least one control device for setting an outlet temperature of the metal strip emerging from the rolling train.

Metal strips are rolled to the desired outlet thickness in rolling mills. The metal strip coming out of a rolling train is reeled into a spool or a coil. A temperature of the reeled metal strip is important for the quality of the respective metal strip, in particular for metal strips made of certain aluminum alloys. The temperature of such a metal strip must be kept within a relatively narrow temperature range in order to achieve specified mechanical properties of the metal strip.

DE 20 2014 011 231 U1 relates to a system comprising a first frame having a first pair of work rolls for reducing a thickness of a material to a first specified point, a second frame having a second pair of work rolls for reducing the thickness of the material to a second specified point, and a temperature sensor positioned to measure the temperature of the material as it exits the second rack. In addition, the system has a control unit which is coupled to the temperature sensor, the first frame and the second frame in order to adapt at least one of the first specified point and the second specified point on the basis of the temperature of the material measured by the temperature sensor, with the it emerges from the second frame.

EP 2 697 002 B1 relates to a control method for a rolling train, whereby for strip sections of a strip in front of a first roll stand of the rolling train a temperature is determined which the strip sections have, whereby the temperatures of the strip sections for the time of rolling of the respective strip section are determined by means of a strip model based on the determined temperatures the first roll stand, with at least one respective control parameter for the rolling of the strip sections in the first roll stand being determined using the predicted temperatures of the strip sections, and wherein an adjusting device acting on the first roll stand during the rolling of the respective strip section taking into account the respective determined Control parameter is controlled. The temperatures of the strip sections are forecast for the point in time when the respective strip section is rolled in the first roll stand by means of the strip model with a first forecast horizon. The first forecast horizon corresponds to several strip sections to be rolled in the first roll stand. For the first forecast horizon, a manipulated variable curve is used for the actuating device. A profile of a roll gap formed by work rolls of the first roll stand is influenced by the manipulated variable curve. By means of a roll stand model for the first roll stand, using the predicted temperatures of the strip sections and the set control variable curve for the strip sections corresponding to the first forecast horizon, a respective roll gap profile is predicted that the work rolls of the first roll stand form at the time of rolling of the respective strip section. The set course of the manipulated variable is optimized on the basis of the roll gap profile forecast for the strip sections and a respective target profile. The current value of the optimized manipulated variable curve corresponds to the control parameter and is given to the adjusting device as a manipulated variable.

EP 3 089 833 B1 relates to a system with a first stand having a first pair of work rolls to reduce a thickness of a material to a first set point, a second stand having a second pair of work rolls to reduce the thickness of the material to a second set point reduce, and a temperature sensor arranged to measure the temperature of the material as it leaves the second stand. In addition, the system has a controller, which is coupled to the temperature sensor, the first stand and the second stand, to adjust at least one of the first set point and the second set point based on the temperature of the material measured by the temperature sensor as it leaves the second stand, adjust.

The article "Study on Temperature Prediction Model of Cold Rolling Strip", Chen Junyi et al., International Conference on Artificial Intelligence and Big Data, 2018 discloses a temperature prediction model for a cold rolling process, wherein a run-out temperature of a metal strip rolled in a tandem rolling mill is calculated using parameters which influence the run-out temperature and which have been optimized in advance using a particle swarm optimization process.

Conventionally, when cold rolling aluminum strip in a rolling train, the strip temperature is measured directly, which is time-consuming and expensive. This temperature measurement can be due to a Sensor error or incorrect alignment of a sensor can be disturbed or fail completely. In addition, changes in lead when the load is redistributed between rolling stands of a rolling train temporarily disrupts the exit thickness of the metal strip, since a thickness monitor control in the last rolling stand has dynamic disadvantages due to a transport dead time to the thickness measuring system. A conventional temperature controller must therefore work very slowly in order to impair a target thickness of the metal strip as little as possible.

One object of the invention is to create a more cost-effective, realizable method for setting an outlet temperature of a metal strip exiting a rolling train, with which a metal strip of higher quality can be produced.

This problem is solved by the independent patent claim. Advantageous refinements are given in the following description and the dependent claims, whereby these refinements taken individually or in various combinations of at least two of these refinements with one another can represent a further developing, in particular also preferred or advantageous, aspect of the invention.

According to a method according to the invention for setting an exit temperature of a metal strip exiting from an at least two-stand rolling mill, the exit temperature is determined by means of a process model, taking into account a relationship between strip deformation and / or a cooling rate of the metal strip by at least one cooling medium and by at least one fixed rolling train component and / or one Rolling speed set in a last roll stand of the rolling train on the one hand and the outlet temperature on the other hand. In addition, after using the process model to determine an intervention-related deviation of the strip deformation and / or the rolling speed in the last roll stand from the set values contained in the context for the strip deformation and / or the rolling speed in the last roll stand, a deviation due to the intervention is made using the process model The associated deviation of the outlet temperature from a setpoint temperature contained in the context is determined, with the strip deformation in the last roll stand and in one or more upstream roll stands of the rolling train being changed by means of the process model as a function of the deviation in the outlet temperature in such a way that the outlet temperature corresponds to the setpoint temperature.

The relationship between the strip deformation and / or the rolling speed in the last roll stand of the rolling train on the one hand and the run-out temperature, in particular at the respective working point, on the other hand can be calculated by means of a higher-level pass schedule computer. An operating point is understood to mean all setting values (relating to the physical properties of deformation, thickness, speed, temperature) of an area within which rolling is carried out (target pass schedule), as well as the areas in between that are passed through to reach the area. One or any number of operating points can be taken into account. Four working points are particularly favorable for the purposes of the invention, since they contain all the important corner points of the rolling process without requiring too much computing time to determine them. The pass schedule calculator is set up to define this relationship as the setting state and to transfer coefficients corresponding to the setting state to the (mathematical) process model. In addition, the pass schedule computer can be set up to transfer corresponding coefficients to a device for controlling actuators of the rolling train. These coefficients can consist of one or more terms or of terms composed of them of the quantities listed below as examples: $$\frac{\partial P}{\partial \Delta T},\frac{\partial \mathrm{F.}}{\partial \Delta T},\frac{\partial \mathrm{M.}}{\partial \Delta T},\frac{\partial v}{\partial \Delta T},\frac{\partial \dot{Q}}{\partial \Delta T},\frac{\partial T_f}{\partial \Delta T},\frac{\partial \Delta H}{\partial \Delta T},\frac{\partial f_v}{\partial \Delta T},\frac{\partial l_{vn}}{\partial \Delta T}.$$

T is the temperature, P is the rolling power, F is the rolling force, M is the rolling torque, v is the rolling speed, T _{f is} the fluid temperature, Q is the fluid volume flow, h is the thickness of the rolling stock, Δh is the decrease, I _{VN is} the length of a strip at constant strip speed and f _v the lead.

The cooling medium can be, for example, air, water, oil or an emulsion. The rolling train component can be, for example, a roller or a work roll.

The process model can be set up to monitor directly or indirectly whether a current state of the rolling train corresponds to the setting state. If this set state is not achieved during rolling operation through other controller interventions or if the strip deformation and / or the cooling rate of the metal strip changes due to the application of a cooling medium to the metal strip and the contact of the metal strip with at least one fixed rolling train component and / or the rolling speed in the roll gap of the In the last roll stand, for example due to the intervention of an operating staff, the process model according to the invention can use the coefficients supplied by the pass schedule computer to calculate the deviation of the strip forming and / or the rolling speed in the last Roll stand determine from the set values contained in the context for the strip deformation and / or the rolling speed in the last roll stand a deviation of the outlet temperature associated with the intervention-related deviation from a setpoint temperature contained in the context. The process model is also set up to change the strip deformation in the last roll stand and in one or more upstream roll stands of the rolling train with respect to a strip conveying direction through the rolling train depending on the determined deviation of the outlet temperature in such a way that the outlet temperature corresponds to the target temperature. As a result, the exit temperature of the metal strip is set by means of the process model, taking into account the relationship described above. For this purpose, the process model can change the strip forming and / or the rolling speed and / or the cooling rate or the associated amount of coolant in the last roll stand and the one or more upstream roll stands so that the run-out temperature of the metal strip returns to the target temperature.

The metal band can be, for example, an aluminum band or a steel band. The rolling train can be, for example, a cold rolling tandem train. The last rolling stand of the rolling train is the last rolling stand with regard to a mass flow or a direction of movement of the metal strip through the rolling train. The same applies to the at least one upstream roll stand of the rolling train. The rolling train has at least two, three or more rolling stands. The direction of movement of the metal strip through the rolling train can also change, e.g. B. with a reversing stitch.

The model-based temperature setting according to the invention has the advantage that, ideally, it does not require any sensor system. This reduces investment, commissioning and maintenance costs. A simple off-line temperature measurement on the wound coil would be sufficient for process model validation. The process model also ensures that temperature setting and thickness control are decoupled, so that the quality of the end product can be increased by minimizing mutual interference between different controls. The dynamics of the temperature setting are at a consistently high level for different products thanks to the process model. The invention thus represents a model-based approach of a temperature setting fully integrated into a rolling mill control architecture, which compared to the prior art with a lower investment requirement, for example due to the elimination of the expensive thermal imaging camera common with aluminum strips, lower commissioning costs, lower operating costs, in particular maintenance costs and replacement costs , higher control quality and dynamics, better product quality and greater reliability.

An essential advantage of the invention compared to a conventional temperature controller is that the outlet temperature can be set at an earlier point in time in the rolling process, particularly in the case of a system in batch operation. In addition, it is advantageous that the method according to the invention works more evenly over the length of the strip and is more dynamic, since the process data are determined directly in the roll gap and are not subject to dead time due to the transport to the temperature measuring point. It is also advantageous that the method according to the invention allows higher rates of change over time for setting the target temperature.

According to an advantageous embodiment, a change in a decrease in a strip thickness of the metal strip in the last roll stand required to achieve the target temperature is determined by means of the process model and a roll gap height in one or more upstream roll stands by one of the change in the strip thickness of the metal strip in the amount corresponding to the last roll stand changed in the opposite direction. If, for example, the rolling speed of the pass plan or the setting state calculated by the pass plan computer is not reached, the run-out temperature of the metal strip is too low. The process model can then increase the strip deformation in the last roll stand in order to achieve a desired run-out temperature of the metal strip even at the lower rolling speed. Changing the strip deformation in the last roll stand alone would, however, result in a disturbance in the target thickness of the metal strip. A thickness control of the rolling train would correct this change in thickness and restore the initial state. To prevent this, the process model also uses the coefficients supplied by the pass schedule calculator to calculate a required change in the strip forming in one or more upstream roll stands, so that, together with the strip forming in the last roll stand, required to set the desired exit temperature of the metal strip, the desired exit thickness of the metal strip remains unchanged remains. For example, if the process model calculates a percentage change in the decrease or reduction in the thickness of the metal strip in the last roll stand of + 15% required to achieve the desired exit temperature of the metal strip, the decrease or reduction in the thickness of the metal strip in one or more upstream roll stands will be as follows compensates for the fact that the total decrease remains constant. Becomes the strip thickness of the metal strip is initially reduced, for example, from 0.4 mm to 0.3 mm in the penultimate roll stand and from 0.3 mm to 0.2 mm in the last roll stand and if there is an aforementioned deviation in the run-out temperature of the metal strip, the process model can Change the strip deformation using the last two roll stands in such a way that the strip thickness with the penultimate roll stand is reduced from 0.4 mm to 0.345 mm and with the last roll stand from 0.345 mm to 0.2 mm, so that the outlet thickness of the metal strip is not affected . The respective manipulated variable is the roll gap height of the respective roll stand calculated by the process model.

According to a further advantageous embodiment, a separate stand model contained in the process model is used for the last roll stand and for one or more upstream roll stands, which is adapted at time intervals by pressing the respective roll stand without a metal strip. The (mathematical) framework model is a framework model that is calibrated by the impression (calibration process). During the pressing, the work rolls of the respective roll stand are brought into contact with one another, with travel distances, forces and the like being able to be recorded, for example by means of the process model, in order to adapt the stand model.

According to a further advantageous embodiment, a cooling model contained in the process model is used, with which cooling of the metal strip is calculated by optionally applying various coolants and cooling of the metal strip due to contact with work rolls. The various coolants can be, for example, air, water, oil or an emulsion. The contact of the metal strip with the work rolls results in a heat flow through which heat flows away from the metal strip via the work rolls, so that the metal strip is cooled. When calculating the respective cooling of the metal strip, the cooling model can take into account flow temperatures, volume flows and dwell times in the relevant system parts. The cooling capacity can be calculated using coefficients that are determined by the pass schedule calculator.

According to a further advantageous embodiment, an inlet temperature level of a coil from the metal strip is taken into account in the process model before it enters the rolling train. This information is also required for setting up the system. A distinction must primarily be made here as to whether it is a coil that has cooled to room temperature or a coil that has been heated above room temperature due to hot rolling or annealing processes. This can be done through a manual or inline temperature measurement in the inlet of the rolling train or through a calculation of the cooling based on data from process steps over time from the production planning.

According to a further advantageous embodiment, changes in the strip deformations in the last roll stand and one or more upstream roll stands are pre-controlled by means of a tracking module by shifting the respective change in strip thickness into the respective roll stand with a respective measured strip speed. The tracking module ensures that the variations of the manipulated variables calculated by the coefficients take place in the downstream rolling stands at the correct time, so that when the correct outlet temperature is set, there are no thickness disturbances at any point in time. In a transient area in which the thickness of the metal strip changes, the tracking module can redistribute the strip deformation in the roll gaps of the last roll stand and one or more upstream roll stands so that a desired outlet thickness of the metal strip is not disturbed. Since the respective change in the strip thickness of the metal strip is shifted with the measured strip speed into the following, in particular the last, roll stand, a change in the pitch in the roll gap of the following roll stand is timed correctly as in the preceding, in particular one or more upstream, Roll stand (s) started.

According to a further advantageous embodiment, the temperature change due to the rolled strip length is determined as a function of the strip speed by means of the process model.

According to a further advantageous embodiment, changes in roll gap heights in the last roll stand and one or more upstream roll stands are compensated for by means of the process model by changing the speeds of the work rolls of the last roll stand or the one or more upstream roll stands, the speeds being determined using a or the mass flow contained in the process model through the rolling train can be determined. The changes in lead and strip thickness can be pre-controlled by the deformation redistribution in such a way that, ideally, the thickness control behind the last roll stand does not cause any disruption. This can be achieved, for example, in that a change in the pitch in the last roll stand and in one or more upstream roll stands is compensated for by the change in speed corresponding to the mass flow in the roll stand (s) concerned. This leaves a Strip tension, regardless of whether a tension control affects the pitch or the stand speed, remains unchanged.

According to a further advantageous embodiment, changes in the lead of the metal strip are taken into account by means of the process model when the strip speed is corrected if the process model has determined a deviation in the strip forming and / or the rolling speed in the last roll stand due to the intervention of an actuator of another control device of the rolling train. The changes in lead can be taken into account in the speed correction, for example, via the difference quotients of the pass schedule model. If the process model detects a deviation of the strip forming from the set state due to an intervention by an actuator, for example a thickness control or tension control, the process model can switch on the speed correction in an analogous manner. Since the process model can work continuously and the strip deformation can be continuously distributed between the roll stands and, in addition, changes in advance can be controlled, in the ideal case there is no disturbance of the desired outlet thickness of the metal strip. If, for example, the decrease in the last roll stand is less than planned in the settlement (input variables: run-out thickness, rolling torque and rolling force in the last roll stand), then the decrease in one or more upstream roll stands is reduced so that the decrease in the last roll stand can be increased. The greater deformation then leads to the desired increase in the outlet temperature. The changes in speed and advance that occur during the relocation are pre-controlled by the changed mass flow balance and advance coefficient d advance / d decrease in the roll stands concerned, so that there are no tension and thickness disturbances during the relocation.

According to a further advantageous embodiment, the relationship between the strip deformation and / or the cooling rate of the metal strip by at least one cooling medium and by at least one fixed rolling train component and / or the rolling speed in the last roll stand on the one hand and the outlet temperature on the other hand with the help of temperature measurements on the one from the rolling train adapted to the outgoing metal band. For example, the actual coil temperature can be measured, for example, with a hand-held measuring device at the end of a rolling program. Inline temperature measurement is more convenient but more complex. The measured values of the respective temperature measurement can be sent automatically to the pass schedule computer, which compares the calculated and measured temperature with a calculated temperature value and adapts the calculated temperature value to the measured value. Other model parameters can also be adapted here.

A control device according to the invention for setting an outlet temperature of a metal strip exiting from an at least two-stand rolling train is set up to carry out the method according to one of the above-mentioned configurations or a combination of at least two of these configurations with one another.

The advantages mentioned above with reference to the method are correspondingly associated with the control device. The control device can be provided as a separate device or implemented by software implementation in the existing system electronics of a rolling mill. The control device can be used as a predictive temperature controller of a rolling mill on the basis of a process model.

A rolling plant according to the invention for rolling a metal strip has at least one rolling train with at least two stands and at least one control device mentioned above for setting an outlet temperature of the metal strip emerging from the tandem rolling train.

The advantages mentioned above with reference to the method are correspondingly associated with the rolling installation. The rolling mill can be designed as a multi-stand cold rolling tandem mill, in particular for the production of aluminum strip.

• 1 eine schematische Darstellung eines Ausführungsbeispiels für eine erfindungsgemäße Walzanlage;
• 2 eine schematische Darstellung eines weiteren Ausführungsbeispiels für eine erfindungsgemäße Walzanlage;
• 3A eine schematische Darstellung eines Gerüstmodells eines Ausführungsbeispiels für ein erfindungsgemäßes Prozessmodell;
• 3B eine schematische Darstellung eines Kühlmodells eines Ausführungsbeispiels für ein erfindungsgemäßes Prozessmodell; und
• 3C eine schematische Darstellung eines Trackingmoduls eines Ausführungsbeispiels für ein erfindungsgemäßes Prozessmodell.

In the following, the invention is explained by way of example with reference to the attached figures using a preferred embodiment, wherein the features explained below can represent an advantageous or further developing aspect of the invention both individually and in combination of at least two of these features with one another. Show it:

• 1 a schematic representation of an embodiment for a rolling mill according to the invention;
• 2 a schematic representation of a further embodiment for a rolling mill according to the invention;
• 3A a schematic representation of a framework model of an exemplary embodiment for a process model according to the invention;
• 3B a schematic representation of a cooling model of an embodiment for a process model according to the invention; and
• 3C a schematic representation of a tracking module of an exemplary embodiment for a process model according to the invention.

Identical or functionally identical components are provided with the same reference symbols in the figures. A repeated description of these components can be omitted.

1 shows a schematic representation of an exemplary embodiment for a rolling mill according to the invention 1 for rolling a metal strip 2 . The rolling mill 1 has a three-stand rolling mill 3rd and a symbolically shown control device 4th for setting an outlet temperature from the rolling train 3rd exiting metal band 2 on. The control device 4th is for carrying out a method according to the invention for adjusting the outlet temperature of the rolling train 3rd expiring metal tape 2 set up.

In 1 different sizes and their relationships are shown. Here, P _{1 is} the nominal rolling capacity of the first roll stand 5 and P ' _{1 is} the actual rolling capacity of the first roll stand 5 . h ₁₀ is the inlet thickness of the into the first roll stand 5 incoming rolled strip 2 and h ₁₁ is the outlet thickness of the from the first roll stand 5 expiring rolled strip 2 , where Δh _{1 is} the decrease in the thickness of the rolled strip 2 in the first roll stand 5 is. v ₁ is the strip speed of the first roll stand 5 leaving rolled strip 2 and S ₁₂ is the strip tension in the rolled strip 2 between the first roll stand 5 and one of the first roll stand 5 downstream second roll stand 6th .

P _{2 is} the target rolling capacity of the second roll stand 6th and P ' _{2 is} the actual rolling capacity of the second roll stand 6th . h ₂₀ is the inlet thickness of the into the second roll stand 6th incoming rolled strip 2 and h ₂₁ is the outlet thickness of the from the second roll stand 6th expiring rolled strip 2 , where Δh _{2 is} the decrease in the thickness of the rolled strip 2 in the second roll stand 6th is. v ₂ is the strip speed of the second roll stand 6th leaving rolled strip 2 and S ₂₃ is the strip tension in the rolled strip 2 between the second roll stand 6th and one the second roll stand 6th downstream third or last roll stand 7th .

P _{3 is} the target rolling capacity of the third roll stand 7th and P ' _{3 is} the actual rolling capacity of the third stand 7th . h ₃₀ is the inlet thickness of the into the third roll stand 7th incoming rolled strip 2 and h ₃₁ is the outlet thickness of the from the third roll stand 7th expiring rolled strip 2 , where Δh _{3 is} the decrease in the thickness of the rolled strip 2 in the third roll stand 7th is. v ₃ is the strip speed of the third roll stand 7th leaving rolled strip 2 .

T is the target temperature of the rolling train 3rd outgoing cold or hot strip 2 and T 'is the actual temperature of the mill train 3rd outgoing cold or hot strip 2 , where ΔT is the temperature difference between the target temperature and the actual temperature.

In the lower area of 1 the relationships between the above-mentioned variables are shown, which enable the outlet temperature T 'to be set according to the invention.

2 shows a schematic representation of a further exemplary embodiment of a rolling plant according to the invention for rolling a metal strip (not shown), with only one pass schedule computer of the rolling plant 8th and the process model 9 are shown with reference to a roll stand n.

The pass schedule calculator 8th an inlet temperature T0 of the hot strip, an outlet temperature T of the hot strip, a decrease in thickness Δh within the roll stand n as well as material and system data A are supplied. The pass schedule calculator 8th determined from this on the right in 2 The coefficients and setting values shown, which are common to the process model 9 are fed.

The process model 9 the current rolling power P (n) of the roll stand n, a current rolling moment M (n) of the roll stand n, a current rolling force F (n) of the roll stand n, a current rolling speed v (n) of the roll stand n, a current roll deformation Δh (n) in the roll stand n, a current coolant temperature Tf (n) at the roll stand n and a current coolant volume flow Q (n) at the roll stand n. Furthermore, the process model 9 optionally calibration curves K (n) of the roll stand n and optionally a measured actual temperature T are supplied. The process model determines from this 9 a rolling speed change Δv (n) over time t and a decrease change Δh (n) over time t for the roll stand n. For this purpose, the process model 9 a scaffolding model 10 , a cooling model 11 and a tracking module 12th on.

3A shows a schematic representation of a framework model 10 of an exemplary embodiment for a process model according to the invention. The scaffolding model 10 the current rolling force F (n) of a roll stand n and a current roll deformation Δh (n) in the roll stand n are supplied. Furthermore, the scaffolding model 10 a framework module G (n) and a belt module B (n) are supplied. The scaffolding model is determined from this 10 a setting position deviation Δs (n) from a setting value s (n) of the roll stand n. The stand model 10 can look in the process model 2 be implemented.

3B shows a schematic representation of a cooling model 11 of an exemplary embodiment for a process model according to the invention. The cooling model 11 become a current rolling speed v (n) of the roll stand n, a current coolant temperature Tf (n) at the roll stand n and a current coolant volume flow Q (n) at the roll stand n. Furthermore, the cooling model 11 System data A (n) supplied. The cooling model determines from this 11 a strip temperature deviation ΔT (n) from a set value T (n) on the roll stand n. The cooling model 11 can look in the process model 2 be implemented.

3C shows a schematic representation of a tracking module 12th of an exemplary embodiment for a process model according to the invention. The tracking module 12th are made from the scaffolding model 3A determined pitch position deviation Δs (n) of the roll stand n and the current rolling speed v (n) of the roll stand n supplied. Furthermore, the tracking module 12th System data A (n) supplied. The tracking module determines from this 12th a change in the rolling speed Δv (n) over time t and a change in decrease Δh (n) over time t for the roll stand n. The tracking module 12th can look in the process model 2 be implemented.

List of reference symbols

1

Rolling mill

2

Rolled strip

3

Rolling mill

4th

Control device

5

first (upstream) roll stand

6th

second (upstream) roll stand

7th

third (last) roll stand

8th

Pass schedule calculator

9

Process model

10

Scaffolding model

11

Cooling model

12th

Tracking module

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 202014011231 U1 [0003]
• EP 2697002 B1 [0004]
• EP 3089833 B1 [0005]

Non-patent literature cited

• Chen Junyi et al., International Conference on Artificial Intelligence and Big Data, 2018 [0006]

Claims (12)

Method for setting an outlet temperature of a metal strip (2) exiting from an at least two-stand rolling mill (3), the outlet temperature using a process model (9) taking into account a relationship between strip deformation and / or a cooling rate of the metal strip (2) by at least one cooling medium and by at least one fixed rolling train component and / or a rolling speed in a last roll stand (7) of the rolling train (3) on the one hand and the run-out temperature on the other hand, characterized in that after an intervention-related deviation of the Band deformation and / or the rolling speed in the last roll stand (7) from the set values contained in the context for the band deformation and / or the rolling speed in the last roll stand (7) by means of the process model (9) a deviation associated with the intervention-related deviation g the outlet temperature is determined from a setpoint temperature contained in the context, the strip deformation in the last roll stand (7) and in one or more upstream roll stands (5, 6) of the rolling train (3) by means of the process model (9) depending on the deviation the outlet temperature is changed in such a way that the outlet temperature corresponds to the setpoint temperature. Procedure according to Claim 1 , characterized in that by means of the process model (9) depending on the deviation of the outlet temperature, a change in a decrease in a strip thickness of the metal strip (2) in the last roll stand (7) required to achieve the target temperature is determined and a roll gap height in one or more upstream ones Roll stands (5, 6) is changed in the opposite direction by an amount corresponding to the change in the strip thickness of the metal strip (2) in the last roll stand (7). Procedure according to Claim 1 or 2 , characterized in that a separate frame model (10) contained in the process model (9) is used for the last roll stand (7) and for one or more upstream roll stands (5, 6), which is produced at time intervals by printing the respective Roll stand (5, 6, 7) is adapted without metal strip (2). Method according to one of the Claims 1 to 3rd , characterized in that a cooling model (11) contained in the process model (9) is used, with which a cooling of the metal strip (2) by an optional application of various coolants and a cooling of the metal strip (2) due to contact with work rolls is calculated becomes. Method according to one of the Claims 1 to 4th , characterized in that an inlet temperature level of a coil from the metal strip (2) is taken into account in the process model (9) before it enters the rolling train (3). Method according to one of the Claims 1 to 5 , characterized in that changes in the strip deformations in the last roll stand (7) and in one or more upstream roll stands (5, 6) are precontrolled by means of a tracking module (12) by converting the respective change in the strip thickness to the respective measured strip speed Roll stand (5, 6, 7) is moved. Method according to one of the Claims 1 to 6th , characterized in that the temperature change due to the rolled strip length is determined as a function of the strip speed by means of the process model (9). Method according to one of the Claims 1 to 7th , characterized in that changes in roll gap heights in the last roll stand (7) and in one or more upstream roll stands (5, 6) by means of the process model (9) by changes in the speeds of work rolls of the last roll stand (7) or the one or of the plurality of upstream rolling stands (5, 6) are compensated, the speeds being determined using a mass flow through the rolling train (3) that has been determined or is contained in the process model (9). Method according to one of the Claims 1 to 8th , characterized in that, by means of the process model (9), changes in advance of the metal strip (2) are taken into account when the strip speed is corrected if the process model (9) shows a deviation in the strip forming and / or the rolling speed in the last roll stand (7) due to an intervention has determined an actuator of another control device of the rolling train (3). Method according to one of the Claims 1 to 9 , characterized in that the relationship between the strip deformation and / or the cooling rate of the metal strip (2) by at least one cooling medium and by at least one fixed rolling train component and / or the rolling speed in the last roll stand (7) on the one hand and the outlet temperature on the other hand with the help of temperature measurements is adapted to the metal strip (2) exiting from the rolling train (3). Control device (4) for setting an outlet temperature of a metal strip (2) exiting from an at least two-stand rolling train (3), characterized in that the control device (4) for carrying out the method according to one of the Claims 1 to 10 is set up. Rolling plant (1) for rolling a metal strip (2), having at least one at least two-stand rolling train (3) and at least one control device (4) for setting an outlet temperature of the metal strip (2) emerging from the rolling train (3), characterized in that the Control device (4) after Claim 11 is trained.

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