Method for operating a pre-strip cooler in a hot strip mill, hot strip mill having a pre-strip cooler arranged between a pre-rolling mill and a finish-rolling mill

Abstract

The present invention discloses a method for operating a pre-strip cooler (20) in a hot strip mill (100) for producing a hot strip (60), wherein the method comprises the following method steps: - pre-rolling (S1) the metal rolling stock (40) by means of a pre-rolling mill (10) to form a pre-strip (50); - cooling (S2) the pre-strip (50) by means of the pre-strip cooler (20); - finish-rolling (S3) the cooled pre-strip (50) to form a hot strip (60) by means of a finish-rolling mill (60), wherein the method is characterised in that the cooling (S2) of the pre-strip (50) is controlled or regulated by means of the pre-strip cooler (20) in such a way that the pre-strip (50) output from the pre-strip cooler (20) has a temperature distribution along the longitudinal extent (L) of the pre-strip such that a front portion (51) of the pre-strip (50) has a lower temperature than a rear portion (52) of the pre-strip (50). The present invention further discloses a computer program product and a hot strip mill (100) for producing a hot strip (60).

Description

[0001] Page 1 / 32Applicant: SMS group GmbHOur reference: P80921WODecember 16, 2024 Method for operating a transfer strip cooler in a hot strip mill, hot strip mill with a transfer strip cooler arranged between a roughing mill and a finishing mill. The present invention relates to a method for operating a transfer strip cooler in a hot strip mill for producing hot strip. Furthermore, the present invention relates to a hot strip mill for producing hot strip. Hot strip mills for producing hot strip have a roughing mill for rough-rolling a metallic rolling stock into a transfer strip. A finishing mill is arranged downstream of the roughing mill in the conveying direction of the metallic rolling stock and the transfer strip, which finish-rolls the transfer strip into hot strip. The transfer strip fed to the finishing mill is generally cooled in air and then fed to the finishing mill. The finish-rolled hot strip is then generally coiled.In individual hot strip mills, a pre-strip cooler is arranged between the roughing mill and the finishing mill, by means of which the pre-strip is cooled by a specific temperature between individual passes (rolling operations) carried out in the roughing mill during the roughing process. Correspondingly designed hot strip mills are not very flexible with regard to their operation for producing different hot strips, which, for example, result from metallic rolling stock with different initial thicknesses and possibly different material compositions. The present invention is based on the object of providing a method for operating a pre-strip cooler in a hot strip mill for producing a hot strip, by means of which the productivity of the hot strip mill can be increased and by means of which the material quality of the produced hot strip can be improved. This object underlying the present invention isby a method for operating a pre-strip cooler in a hot strip mill for producing a hot strip with the features of claim 1. Advantageous embodiments of the method are described in the claims dependent on claim 1. More specifically, the object underlying the present invention is achieved by a method for operating a pre-strip cooler in a hot strip mill for producing a hot strip, wherein the hot strip mill has a roughing mill for receiving a metallic rolling stock and for discharging a pre-strip, a finishing mill for receiving a pre-strip and for discharging a hot strip, and a pre-strip cooler, which is arranged between the roughing mill and the finishing mill and is designed to cool a pre-strip by applying a cooling fluid discharged via a plurality of cooling fluid nozzles that can be controlled individually or in groups. The method comprises a method step for pre-rolling themetallic rolling stock by means of the roughing mill to form a roughing strip, a process step for cooling the roughing strip by means of the roughing strip cooler, and a process step for finish-rolling the cooled roughing strip to form a hot strip. The process according to the invention is characterized in that the cooling of the roughing strip by means of the roughing strip cooler is controlled or regulated in such a way that the roughing strip output from the roughing strip cooler has a temperature distribution along its longitudinal extent such that a front section of the roughing strip has a lower temperature than a rear section of the roughing strip. The process according to the invention enables more productive and faster operation of a hot strip mill for producing a hot strip. This is because by controlling or regulating the roughing strip cooler in such a way that the roughing strip output from the roughing strip cooler has a temperature distribution such that a front section of the roughing striphas a lower temperature than a rear section of the transfer strip, the transfer strip can be finish-rolled more quickly in the finishing mill at a higher rolling speed to produce hot strip with a desired and / or required final rolling temperature. The sections of the transfer strip downstream of the front section in the conveying direction cool down further during the rolling of the front section, so that their temperature also has a desired low temperature upon entering the finishing mill, so that these sections can also be finish-rolled at a higher rolling speed to produce hot strip with a desired and / or required final rolling temperature. Due to the increase in the rolling speed in the finishing mill, a spatial gap to the subsequent rolling stock is increased. As a consequence, this fundamentally results in an increase in the productivity of the finishing mill and thus of the entire hot strip mill (taking into account theProduct properties, product target data (e.g., final rolling temperature, rolling forces, drive power, penetration impact) and the possibility of shifting the bottleneck for production planning or for the production control system (pacing). In conjunction with a pass schedule calculation of the roughing mill and the finishing mill, the pacing can then determine an optimum that takes into account the respective rolling times in the individual areas. The method according to the invention further has the advantage that the amount of cooling fluid required to achieve a desired temperature distribution of the roughing strip before entering the finishing mill is minimized. A further advantage of the method according to the invention is that scale formation on the roughing strip is reduced, thereby reducing the effort required for scale removal from the roughing strip and / or the hot strip. The metallic rolling stock is preferably in the form of a slab. The roughing strip is produced by rough rollingof the metallic rolling stock in the roughing mill. The hot strip is produced by rolling the roughing strip in the finishing mill. The roughing mill and / or the finishing mill is / are preferably designed such that they are each designed for reversible rolling or non-reversible rolling. The cooling fluid is preferably water or predominantly water. The front section of the roughing strip is fed to the finishing mill before the rear section of the roughing strip if the roughing strip is transported in the transport direction of the hot strip mill during the rolling process. The front section of the roughing strip can also be referred to as the first section or the head of the roughing strip. The rear section of the roughing strip can also be referred to as the second section or the foot of the roughing strip. Page 5 / 32 P80921WO The front section preferably comprises the front end of the roughing strip. The rear section preferably comprises the rear end of the roughing strip. If in theWhen reference is made in the present invention to the temperature of a metallic rolling stock and / or a preliminary strip and / or a hot strip, this is to be understood as a surface temperature and / or a temperature distribution along the thickness of the metallic rolling stock and / or the preliminary strip and / or the hot strip. When reference is made in the present invention to determining a temperature, this is to be understood as a measurement and / or a calculation of the temperature, thus in particular also a calculation of a temperature distribution along the thickness of the metallic rolling stock and / or the preliminary strip and / or the hot strip. The calculation of the temperature or the temperature distribution is preferably carried out using the finite element method. The roughing mill can also be referred to as a roughing train and / or a roughing mill. The finishing mill can also be referred to as a finishing mill and / or a finishing mill.Preferably, the method is designed such that, during the production of successive hot strips, i.e., a first hot strip produced first and a second hot strip following one after the other, the first preliminary strip, from which the first hot bath results from finish rolling in the finishing mill, is cooled more intensively. Further preferably, the method is designed such that the first preliminary strip is cooled to a lower temperature than the second preliminary strip by means of the preliminary strip cooling. This makes it possible for the first preliminary strip to be finish-rolled by means of the finishing mill at a higher rolling speed. Page 6 / 32 P80921WO Preferably, the method is designed such that, during the production of successive hot strips, i.e., a first hot strip produced first and a second hot strip following one after the other, the first preliminary strip, from which the first hot bath results from finish rolling in the finishing mill, is cooled less intensively.is cooled. Further preferably, the method is designed such that the first preliminary strip is cooled to a higher temperature than the second preliminary strip by means of the preliminary strip cooler. This offers particular advantages when the second preliminary strip requires a longer finish-rolling time than the first hot strip. Preferably, the method is designed such that the front section and / or the rear section of the preliminary strip are not cooled by the preliminary strip cooler to a minimum temperature possible for the finish-rolling process. The correspondingly designed method has the advantage that a processing step following the finish-rolling step, e.g., a cutting process of the hot strip or a coiling process of the hot strip, can be carried out in a simplified manner. Further preferably, the method is designed such that the preliminary strip is cooled by means of the preliminary strip cooler to a minimum temperature possible for the finish-rolling process. The correspondingA correspondingly designed method has the advantage that spatial gaps between successive hot strips are enlarged or maximized, so that a roll change of the roughing mill and / or the finishing mill is made easier. Preferably, the method is designed such that the cooling of the pre-strip by means of the pre-strip cooler is controlled or regulated in such a way that the pre-strip output from the pre-strip cooler has a temperature that decreases continuously, preferably strictly monotonically, and more preferably linearly from its rear section to its front section along its longitudinal extent. The correspondingly designed method enables even more productive, since faster, operation of a hot strip mill with simultaneously minimized consumption of cooling fluid. Preferably, the method is designed such that the cooling of the pre-strip by means of the pre-strip cooleris controlled or regulated such that the temperature of the front section of the preliminary strip has a predetermined minimum temperature upon entry into the finishing mill. The correspondingly designed method enables the preliminary strip to be rolled into hot strip at a maximum speed in the finishing mill. Consequently, spatial gaps between successive hot strips are increased or maximized, so that a roll change in the preliminary rolling mill and / or the finishing mill is simplified. The predetermined minimum temperature of the preliminary strip is selected / calculated such that the hot strip output from the finishing mill has a predetermined minimum temperature. The correspondingly designed method has particular advantages when rolling multi-phase steels. Preferably, the method is designed such that the cooling of the preliminary strip by means of the preliminary strip cooler is controlled or regulated such that the temperature of eachThe correspondingly designed method enables the finishing mill to roll the roughing strip into hot strip at a constant maximum speed during the rolling of the roughing strip into hot strip. Page 8 / 32 P80921WO. Consequently, spatial gaps between successive hot strips are enlarged or maximized, so that a roll change in the roughing mill and / or the finishing mill is made even easier. Furthermore, the correspondingly designed method has the advantage of simplifying the control of the rolling speed of the finishing mill. The cooling of the roughing strip by means of the roughing strip cooler is naturally carried out with knowledge of the distance of the roughing strip cooler to the finishing mill and the transport time of the roughing strip from the roughing strip cooler to the finishing mill. Furthermore, the temperature of the roughing strip and preferably also theAmbient temperature is known. Preferably, the method is designed such that the pre-strip cooler is controlled or regulated such that it discharges a decreasing amount of cooling fluid onto the pre-strip via the cooling fluid nozzles over a length of the pre-strip. The correspondingly designed method enables further savings of the cooling fluid required for cooling the pre-strip. The feature according to which the pre-strip cooler discharges a decreasing amount of cooling fluid onto the pre-strip via the cooling fluid nozzles over the length of the pre-strip results in the front section of the pre-strip being exposed to a larger amount of cooling fluid than the rear section of the pre-strip. Preferably, the method is designed such that it comprises a method step for determining a temperature distribution of the pre-strip discharged from the roughing mill, a method step for calculating a target temperature distribution of the pre-strip before entering the finishing mill, and aProcess step for calculating a spatially and temporally resolved cooling fluid flow, which is to be discharged from the cooling fluid nozzles onto the pre-strip passing through the pre-strip cooler, based on the determined temperature distribution of the pre-strip discharged from the roughing mill such that the pre-strip has the target temperature distribution after passing through the pre-strip cooler. The correspondingly designed process enables an even more precise adjustment of the temperature distribution of the pre-strip before entering the finishing mill. Consequently, the correspondingly designed process enables the production of hot strip with improved quality. The temperature distribution is preferably determined by means of a calculation of the temperature distribution. For this purpose, the temperature distribution is preferably calculated using the finite element method. The temperature distribution can also be determined, for example, using one or moreMeasurements and / or by means of a calculation using a simulation model. The temperature distribution of the transfer strip is preferably a temperature distribution in the longitudinal direction and / or in the thickness direction of the transfer strip. Further preferably, the temperature distribution of the transfer strip is a temperature distribution in the width direction of the transfer strip. Calculating the target temperature distribution of the transfer strip before entering the finishing mill means that the target temperature distribution of the transfer strip is calculated for the situation in which the transfer strip has left the transfer strip cooler. Consequently, the target temperature distribution is calculated for the transfer strip located between the transfer strip cooler and the finishing mill. Page 10 / 32 P80921WO Further preferably, the method is designed such that the determination of the temperature distribution of the transfer strip output from the roughing mill is based on a calculated temperature distribution of the metallic rolling stock before entering the roughing mill.The correspondingly designed method enables an even more precise adjustment of the temperature distribution of the preliminary strip before entering the finishing rolling mill. Consequently, the correspondingly designed method enables the production of hot strip with an even better quality. The calculation of the temperature distribution of the metallic rolling stock before entering the roughing mill is preferably calculated using the finite element method. The temperature distribution of the metallic rolling stock is preferably a temperature distribution in the longitudinal direction and / or in the thickness direction of the metallic rolling stock. Further preferably, the temperature distribution of the metallic rolling stock is a temperature distribution in the width direction of the metallic rolling stock. Even more preferably, the method is designed such that the determination of the temperature distribution of the preliminary strip output from the roughing mill is based at least partially on at least onemeasured temperature of the metallic rolling stock before entering the roughing mill. The correspondingly designed method enables an even more precise adjustment of the temperature distribution of the preliminary strip before entering the finishing mill. Consequently, the correspondingly designed method enables the production of hot strip with improved quality. Page 11 / 32 P80921WO Preferably, the temperature distribution of the preliminary strip output from the roughing mill is calculated using a finite element method, with the measured temperature of the metallic rolling stock before entering the roughing mill serving as the basis. Even more preferably, the method is designed such that the calculation of the target temperature distribution of the preliminary strip before entering the finishing mill is based on a predetermined minimum temperature distribution of the hot strip to be output from the finishing mill. The correspondingly designed method enables theThe preliminary strip is rolled into hot strip at a maximum speed in the finishing mill. Consequently, spatial gaps between successive hot strips are enlarged or maximized, so that a roll change in the preliminary rolling mill and / or the finishing mill is simplified. Calculating the target temperature distribution of the preliminary strip before entering the finishing mill requires information about the finishing rolling process, such as the number of rolling passes, the temperature of the rolls in the finishing mill, and the rolling speed in the finishing mill. Preferably, the method is designed such that the method comprises a method step for determining a rolling speed at which the preliminary strip is rolled in the finishing mill, and a method step for calculating the target temperature distribution of the preliminary strip before entering the finishing mill based on the rolling speed in the finishing mill. The correspondingly designed methodenables a further improved utilization of a hot strip mill in which a pre-strip cooler is installed. By taking into account the rolling speed at which the pre-strip is rolled in the finishing mill, Page 12 / 32 P80921WO the pre-strip is cooled just enough so that upon leaving the finishing mill the hot strip has a desired or required temperature. The correspondingly designed method also enables a further saving in the amount of cooling fluid used. The rolling speed can be an actual rolling speed or a maximum possible rolling speed of the finishing mill. In particular, the rolling speed in the last pass is important for calculating the target temperature and thus the amount of cooling fluid to be applied. Further preferably, the method is designed such that the method includes a method step for determining a pre-rolling time within which the metallic rolling stock in the pre-rolling mill is cooled to the pre-stripis pre-rolled, and a method step for calculating the target temperature distribution of the preliminary strip before entering the finishing mill under the condition that a preliminary strip exhibiting the target temperature distribution can be finish-rolled into hot strip in the finishing mill within a finishing time that corresponds to the pre-rolling time. The correspondingly designed method is particularly advantageous for identical consecutive rolled goods / rolled products. The pre-rolling time is the occupancy time of the roughing mill during the pre-rolling of the metallic rolled stock into preliminary strip. The finish-rolling time is the occupancy time of the finishing mill during the finish-rolling of the preliminary strip into hot strip. Preferably, the method is designed in such a way that the method comprises a method step for determining a geometric Page 13 / 32 P80921WO deviation of a pre-strip output from the roughing mill from a target geometry of the pre-strip, and the methodThe step of cooling the pre-strip is carried out taking into account the geometric deviation of the pre-strip in such a way that a top and a bottom of the pre-strip are exposed to cooling fluid in such a way that targeted mechanical stresses are induced in the pre-strip, which cause a deformation of the pre-strip in the direction of the desired geometry. The correspondingly designed method has the advantage that it leads to a significant reduction in camber formation of the pre-strip and thus of the hot strip. For example, asymmetric cooling of the pre-strip with respect to the longitudinal axis of the pre-strip is also possible. The determination of the geometric deviation of the pre-strip output from the roughing mill from a desired geometry can be carried out, for example, with the aid of an optical sensor. The method is preferably designed such that the method includes a method step for determining a temperature distribution of the pre-strip output from the roughing mill.output pre-strip in the width direction of the pre-strip, wherein, based on the determined temperature distribution in the width direction, the process step of cooling the pre-strip by means of the pre-strip cooler is carried out in such a way that the pre-strip output from the pre-strip cooler has a temperature distribution symmetrical with respect to a longitudinal axis of the pre-strip along its width direction. The correspondingly designed process has the advantage that the further processing of the correspondingly cooled pre-strip is improved. Thus, the rolling result of a pre-strip having a corresponding temperature distribution in the finishing mill is improved. Furthermore, due to the temperature distribution symmetrical to the longitudinal axis, mechanical distortion of the pre-strip is reduced, so that the transport of the pre-strip, for example via transport rollers, is improved, since the straight running of the pre-strip during transport is improved.Preferably, the method is designed such that the method comprises a method step for determining a width dimension of the pre-strip and a method step for controlling the cooling fluid nozzles such that the cooling fluid nozzles discharge cooling fluid only onto the pre-strip. The correspondingly designed method reduces the amount of cooling fluid required to cool the pre-strip. Preferably, the cooling fluid nozzles are controlled by switching off cooling fluid nozzles located at the edge. Further preferably, the cooling fluid nozzles are controlled by shading the edges of cooling fluid nozzles located at the edge. Further preferably, the cooling fluid nozzles are controlled by blowing off cooling fluid that is discharged from edge-side cooling fluid nozzles. The object underlying the present invention is further achieved by a computer program product comprising program code means suitable forCarrying out the steps of one of the previously described methods is achieved when the computer program product is executed on a computing device. The object underlying the present invention is further achieved by a hot strip mill for producing a hot strip, wherein the hot strip mill has - a roughing mill for receiving a metallic rolling stock and for outputting a roughing strip, Page 15 / 32 P80921WO - a finishing mill for receiving a roughing strip and for outputting a hot strip, - a roughing strip cooler which is arranged between the roughing mill and the finishing mill and is designed to cool a roughing strip by applying a cooling fluid discharged via a plurality of cooling fluid nozzles which can be controlled individually or in groups, - and a control device which is data-coupled to the roughing strip cooler for outputting control signals, wherein the hot strip mill is designed to carry out one of the methods described above.The hot strip mill preferably has at least one temperature detection device, which is arranged between an output of the roughing mill and an input of the pre-strip cooler and is designed to determine a temperature of the pre-strip output from the roughing mill, wherein the hot strip mill is designed to carry out the following method steps: - determining a temperature distribution of the pre-strip output from the roughing mill; - calculating a target temperature distribution of the pre-strip before entering the finishing mill; - calculating a spatially and temporally resolved cooling fluid flow to be discharged from the cooling fluid nozzles onto the pre-strip passing through the pre-strip cooler, based on the determined temperature distribution of the pre-strip output from the roughing mill such that the pre-strip has the target temperature distribution after passing through the pre-strip cooler. Further advantages, details, and features of the invention will become apparentfollowing from the explained embodiments. In detail: Page 16 / 32 P80921WO Figure 1: a schematic cross-sectional view of a hot strip mill according to the invention; Figure 2: a perspective view of a preliminary strip; Figure 3: a process flow diagram of a method according to a first embodiment of the present invention; Figure 4: a process flow diagram of a method according to a second embodiment of the present invention; Figure 5: a process flow diagram of a method according to a third embodiment of the present invention; Figure 6: a process flow diagram of a method according to a fourth embodiment of the present invention; Figure 7: a process flow diagram of a method according to a fifth embodiment of the present invention; Figure 8: a process flow diagram of a method according to a sixth embodiment of the present invention; and Figure 9: aProcess flow diagram of a method according to a seventh embodiment of the present invention. In the following description, the same reference numerals designate the same components or the same features, so that a description made with reference to one figure regarding a component also applies to the other figures, thus avoiding a repetitive description. Furthermore, individual features described in connection with one embodiment can also be used separately in other embodiments. Furthermore, the methods according to the first to the seventh embodiment can also be combined with one another. Figure 1 shows a hot strip mill 100 for producing a hot strip 60. The hot strip mill 100 has a roughing mill 10 for receiving a metallic rolling stock 40 and for outputting a pre-strip 50. The metallic rolling stock 40 can be designed, for example, as a slab 40. The roughing mill 10 hasseveral rolling stands with several pairs of rolls. The hot strip mill 100 further comprises a finishing mill 30 for receiving the pre-strip 50 and for outputting a hot strip 60. The finishing mill 30 also comprises several rolling stands with several pairs of rolls. The hot strip mill 100 further comprises a pre-strip cooler 20, which is arranged between the pre-strip mill 10 and the finishing mill 30. The pre-strip cooler 20 is designed to cool a pre-strip 50 by applying a cooling fluid discharged via a plurality of cooling fluid nozzles 21 that can be controlled individually or in groups. Furthermore, the hot strip mill 100 comprises a control device 80, which is data-coupled to the pre-strip cooler 20 for outputting control signals. The control device 80 is designed as an electronic control device 80 and can also be referred to as a computing device 80. In the illustrated embodiment of the hot strip mill 100, theThe control device 80 is further data-coupled to the roughing mill 10 and the finishing mill 30, so that, on the one hand, control signals can be transmitted from the control device 80 to the roughing mill 10, the pre-strip cooler 20, and the finishing mill train 30, and, on the other hand, operating parameters from the roughing mill 10, the pre-strip cooler 20, and the finishing mill train 30 can be transmitted to the control device 80. Furthermore, the hot strip mill 100 shown in Figure 1 has a temperature detection device 70 designed to determine a temperature of a pre-strip 50 output from the roughing mill 10. In the illustrated embodiment, the temperature detection device 70 is designed as a pyrometer 70; however, the present invention is not limited to a corresponding design of the temperature detection device 70. The temperature detection device 70 is connected to the control device 80 forTransmission of temperature measurement data in a data-linked manner. The hot strip mill 100 is designed to transport the metallic rolling stock 40, the preliminary strip 50 and the hot strip 60 in a transport direction running parallel to a longitudinal extent L of the preliminary strip 50. A preliminary strip 50 is shown in perspective in Figure 2. The preliminary strip 50 has a longitudinal extent L. The preliminary strip 50 has a front section 51, which is fed to the finishing mill 30 before a rear section 52 of the preliminary strip 50 when the preliminary strip 50 is transported in the transport direction of the hot strip mill 100 during the rolling process. The preliminary strip 50 also has a width B and a height H, wherein the height H can also be referred to as thickness H. The longitudinal extension L, the width extension B, and the height extension H are each arranged perpendicular to each other and span a Cartesian coordinate system. Page19 / 32 P80921WO Figure 3 shows a process flow diagram of a process according to a first embodiment of the present invention. The process is carried out by the hot strip mill 100. In a process step S1, a metallic rolling stock 40 is pre-rolled into a pre-strip 50 by means of the pre-rolling mill 10. In a process step S2, the pre-strip 50 is cooled by means of the pre-strip cooler 20. In a subsequent process step S3, the cooled pre-strip 50 is finish-rolled into a hot strip 60. The control device 80 controls or regulates the pre-strip cooler 20 such that the cooling S2 of the pre-strip 50 by means of the pre-strip cooler 20 takes place such that the pre-strip 50 output from the pre-strip cooler 20 has a temperature distribution along its longitudinal extent L such that the front section 51 of the pre-strip 50 has a lower temperature than the rear section 52 of the pre-strip 50. The cooling S2 of the pre-strip 50 by means of theThe pre-strip cooler 20 can be controlled or regulated by means of the control device 80 such that the pre-strip 50 output from the pre-strip cooler 20 has a temperature that decreases continuously along its longitudinal extent L from its rear section 52 to its front section 51, preferably a temperature that decreases strictly monotonically, more preferably a temperature that decreases linearly. Appropriate cooling is optional and not mandatory. The cooling S2 of the pre-strip 50 by means of the pre-strip cooler 20 can be controlled or regulated by means of the control device 80 such that the temperature of the front section 51 of the pre-strip 50 has a predetermined minimum temperature upon entering the finishing mill 30. Appropriate cooling is optional and not mandatory. The cooling S2 of the pre-strip 50 by means of the pre-strip cooler 20 can be controlled or regulated by means of the control device 80 in such a way that the temperatureEach section of the preliminary strip 50 entering the finishing mill 30 has a predetermined minimum temperature. Corresponding cooling is optional and not mandatory. The cooling S2 of the preliminary strip 50 by means of the preliminary strip cooler 20 can be controlled or regulated by the control device 80 such that the preliminary strip cooler 20 discharges a decreasing amount of cooling fluid onto the preliminary strip 50 via the cooling fluid nozzles 21 over a length of the preliminary strip 50. Corresponding cooling is optional and not mandatory. Figure 4 shows a process flow diagram of a process according to a second embodiment of the present invention. The process is carried out by the hot strip mill 100. In process step S1, a metallic rolling stock 40 is pre-rolled into a preliminary strip 50 by means of the pre-rolling mill 10. Subsequently, in a process step S21, a temperature distribution of the preliminary strip 50 discharged from the pre-rolling mill 10 is determined. Thereafter, inIn a method step S22, a target temperature distribution of the preliminary strip 50 is calculated before entering the finishing rolling mill 30. Following this method step S22, in a method step S23, a spatially and temporally resolved cooling fluid flow is calculated, which is to be discharged from the cooling fluid nozzles 21 onto the preliminary strip 50 passing through the preliminary strip cooler 20, based on the determined temperature distribution of the preliminary strip 50 discharged from the preliminary rolling mill 10 such that the preliminary strip 50 has the target temperature distribution after passing through the preliminary strip cooler 20. In method step S2, the preliminary strip 50 is cooled accordingly by means of the preliminary strip cooler 20. In the subsequent method step S3, the cooled preliminary strip 50 is finish-rolled into a hot strip 60. Page 21 / 32 P80921WO The determination S21 of the temperature distribution of the pre-strip 50 output from the roughing mill 10 can be based on a calculated temperature distribution of the metallic rolling stock 40 before enteringthe roughing mill 10. A corresponding determination S21 is optional and not mandatory. The determination S21 of the temperature distribution of the preliminary strip 50 output from the roughing mill 10 can be based at least partially on at least one measured temperature of the metallic rolling stock 40 before entering the roughing mill 10. For this purpose, a temperature detection device (not shown in Figure 1) can be provided, which is designed to determine the temperature of the metallic rolling stock 40 before entering the roughing mill 10. A corresponding determination S21 is optional and not mandatory. The calculation S23 of the target temperature distribution of the preliminary strip 50 before entering the finishing mill 30 can be based on a predetermined minimum temperature distribution of the hot strip 60 to be output from the finishing mill 30. A corresponding calculation S23 is optional and not mandatory. Figure 5 shows a process flow diagram of a processaccording to a third embodiment of the present invention. The method is carried out by the hot strip mill 100. In method step S1, a metallic rolling stock 40 is pre-rolled into a pre-strip 50 by means of the pre-rolling mill 10. Subsequently, in method step S21, a temperature distribution of the pre-strip 50 output from the pre-rolling mill 10 is determined. Subsequently, in a method step S211, a rolling speed at which the pre-strip 50 is rolled in the finishing mill 30 is determined. Subsequently, in a method step S221, the target temperature distribution of the pre-strip 50 before entering the finishing mill 30 is calculated based on the rolling speed in the finishing mill 30. Following the method step S221, in method step S23 a spatially and temporally resolved cooling fluid flow is calculated, which is to be discharged from the cooling fluid nozzles 21 onto the pre-strip 50 passing through the pre-strip cooler 20, based onthe determined temperature distribution of the preliminary strip 50 output from the roughing mill 10 such that the preliminary strip 50 has the target temperature distribution after passing through the preliminary strip cooler 20. The calculation S23 of the target temperature distribution of the preliminary strip 50 before entering the finishing mill 30 is also based on a predetermined minimum temperature distribution of the hot strip 60 to be output from the finishing mill 30. In method step S2, the preliminary strip 50 is cooled accordingly by means of the preliminary strip cooler 20. In the subsequent method step S3, the cooled preliminary strip 50 is finish-rolled into a hot strip 60. Figure 6 shows a process flow diagram of a process according to a fourth embodiment of the present invention. The process is carried out by the hot strip mill 100. In process step S1, a metallic rolling stock 40 is pre-rolled into a pre-strip 50 by means of the pre-rolling mill 10. Subsequently, in process step S21, aTemperature distribution of the pre-strip 50 output from the roughing mill 10 is determined. Subsequently, in a method step S212, a pre-rolling time is determined within which the metallic rolling stock 40 is pre-rolled in the roughing mill 10 to form the pre-strip 50. Subsequently, in a method step S222, the target temperature distribution of the pre-strip 50 before entering the finishing mill 30 is calculated under the condition that a pre-strip 50 exhibiting the target temperature distribution can be finish-rolled into hot strip 60 in the finishing mill 30 within a finish-rolling time that corresponds to the pre-rolling time. Following process step S222, in process step S23 a spatially and temporally resolved cooling fluid flow is calculated, which is to be discharged from the cooling fluid nozzles 21 onto the pre-strip 50 passing through the pre-strip cooler 20, based on the determined temperature distribution of the pre-strip 50 discharged from the roughing mill 10 in such a way that thePre-strip 50 has the desired temperature distribution after passing through the pre-strip cooler 20. In method step S2, the pre-strip 50 is cooled accordingly by means of the pre-strip cooler 20. In the subsequent method step S3, the cooled pre-strip 50 is finish-rolled into a hot strip 60. Figure 7 shows a process flow diagram of a method according to a fifth embodiment of the present invention. The method is carried out by the hot strip mill 100. In method step S1, a metallic rolling stock 40 is pre-rolled into a pre-strip 50 by means of the pre-rolling mill 10. Subsequently, in a method step S11, a geometric deviation of a pre-strip 50 output from the pre-rolling mill 10 from a desired geometry of the pre-strip 50 is determined. In a subsequent process step S24, the preliminary strip 50 is cooled taking into account the geometric deviation of the preliminary strip 50 such that an upper side 53 and a lower side 54 of the preliminary strip 50strip 50 is subjected to cooling fluid in such a way that targeted mechanical stresses are induced in the preliminary strip 50, causing a deformation of the preliminary strip 50 in the direction of the desired geometry. In the subsequent method step S3, the cooled preliminary strip 50 is finish-rolled into a hot strip 60. Figure 8 shows a process flow diagram of a method according to a sixth embodiment of the present invention. The method is carried out by the hot strip mill 100. In method step S1, a metallic rolling stock 40 is pre-rolled into a preliminary strip 50 by means of the pre-rolling mill 10. Subsequently, in a method step S12, a temperature distribution of the preliminary strip 50 output from the pre-rolling mill 10 is determined in the width direction B of the preliminary strip 50. In a subsequent process step S25, based on the determined temperature distribution in width B, the pre-strip 50 is cooled by means of the pre-strip cooler 20cooled such that the pre-strip 50 output from the pre-strip cooler 20 has a temperature distribution along its width B that is symmetrical with respect to a longitudinal axis L of the pre-strip 50. In the subsequent method step S3, the cooled pre-strip 50 is finish-rolled into a hot strip 60. Figure 9 shows a process flow diagram of a method according to a seventh embodiment of the present invention. The method is carried out by the hot strip mill 100. In method step S1, a metallic rolling stock 40 is pre-rolled into a pre-strip 50 by means of the pre-rolling mill 10. Subsequently, in a method step S13, a width extent of the pre-strip 50 is determined. In a subsequent method step S26, the cooling fluid nozzles 21 are controlled such that they discharge cooling fluid only onto the pre-strip 50.

[0002] Page 25 / 32 P80921WO List of Reference Symbols 10 Roughing Mill 20 Roughing Strip Cooler 21 Cooling Fluid Nozzle 30 Finishing Mill 40 Metallic Rolling Stock 50 Roughing Strip 51 Front Section (of the Roughing Strip) 52 Rear Section (of the Roughing Strip) 53 Top Side (of the Roughing Strip) 54 Bottom Side (of the Roughing Strip) 60 Hot Strip 70 Temperature Detection Device 80 Control Device / Computer Device 100 Hot Strip Mill S1 Process Step S11 Process Step S12 Process Step S13 Process Step S2 Process Step S21 Process Step S211 Process Step S212 Process Step S22 Process Step S221 Process Step S222 Process Step S23 Process Step S24 Process Step S25 Process Step S26 Process Step S3 Process Step L Length Extension (of the Roughing Strip) B Width Extension (of the Roughing Strip) H Height Extension (of the Roughing Strip)

Claims

Page 26 / 32 P80921WO Patent claims 1. Verfahren zum Betrieb eines Vorbandkühlers (20) in einer Hot strip mill (100) for producing a hot strip (60), wherein - die Warmbandstraße (100) ein Vorwalzwerk (10) zur An- receiving a metallic rolling stock (40) and for outputting a pre-strip (50), - ein Fertigwalzwerk (30) zur Annahme eines Vorbandes (50) and for outputting a hot strip (60) and - einen Vorbandkühler (20) aufweist, welcher zwischen the roughing mill (10) and the finishing mill (30) and is designed to cool a preliminary strip (50) by applying a cooling fluid discharged via a plurality of individually or in groups controllable cooling fluid nozzles (21), wherein the method comprises the following method steps: - Vorwalzen (S1) des metallischen Walzgutes (40) mittels of the roughing mill (10) to a pre-strip (50); - Kühlen (S2) des Vorbandes (50) mittels des Vorbandküh- lers (20); - Fertigwalzen (S3) des gekühlten Vorbandes (50) zu ei-a hot strip (60), the method being characterized in that the cooling (S2) of the pre-strip (50) by means of the pre-strip cooler (20) is controlled or regulated in such a way that the pre-strip (50) output from the pre-strip cooler (20) has a temperature distribution along its longitudinal extent (L) such that a front section (51) of the pre-strip (50) has a lower temperature than a rear section (52) of the pre-strip (50). Page 27 / 32 P80921WO 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass das Cooling (S2) of the pre-strip (50) by means of the pre-strip cooler (20) is controlled or regulated in such a way that the pre-strip (50) output from the pre-strip cooler (20) has a temperature which continuously decreases, preferably decreases strictly monotonically, more preferably decreases linearly from its rear section (52) to its front section (51) along its longitudinal extent (L).

3. Verfahren nach einem der vorhergehenden Ansprüche, dadurchcharacterized in that the cooling (S2) of the preliminary strip (50) by means of the preliminary strip cooler (20) is controlled or regulated in such a way that the temperature of the front section (51) of the preliminary strip (50) has a predetermined minimum temperature upon entry into the finishing mill (30).

4. Verfahren nach einem der vorhergehenden Ansprüche, dadurch characterized in that the cooling (S2) of the preliminary strip (50) by means of the preliminary strip cooler (20) is controlled or regulated in such a way that the temperature of each section of the preliminary strip (50) entering the finishing mill (30) has a predetermined minimum temperature.

5. Verfahren nach einem der vorhergehenden Ansprüche, dadurch characterized in that the pre-strip cooler (20) is controlled or regulated in such a way that it discharges a decreasing amount of cooling fluid onto the pre-strip (50) via the cooling fluid nozzles (21) over a length of the pre-strip (50).

6. Verfahren nach einem der vorhergehenden Ansprüche, gekenn- is characterized by the following process steps: - Ermitteln (S21) einer Temperaturverteilung des aus dem Pre-rolling mill (10) output pre-strip (50); - Berechnen (S22) einer Soll-Temperaturverteilung des Pre-strip (50) before entering the finishing mill (30); Page 28 / 32 P80921WO - Berechnen (S23) eines örtlich und zeitlich aufgelösten Cooling fluid flow which is to be discharged from the cooling fluid nozzles (21) onto the pre-strip (50) passing through the pre-strip cooler (20), based on the determined temperature distribution of the pre-strip (50) discharged from the roughing mill (10) such that the pre-strip (50) has the desired temperature distribution after passing through the pre-strip cooler (20).

7. Verfahren nach Anspruch 6, dadurch gekennzeichnet, dass das Determining (S21) the temperature distribution of the pre-strip (50) output from the roughing mill (10) based on a calculated temperature distribution of the metallic rolling stock (40) before entering the roughing mill (10).

8. Verfahren nach Anspruch 6 oder 7, dadurch gekennzeichnet, that the determination (S21) of the temperature distribution of the pre-strip (50) output from the roughing mill (10) is based at least partially on at least one measured temperature of the metallic rolling stock (40) before entering the roughing mill (10).

9. Verfahren nach einem der Ansprüche 6 bis 8, dadurch gekenn-characterized in that the calculation (S23) of the target temperature distribution of the preliminary strip (50) before entry into the finishing mill (30) is based on a predetermined minimum temperature distribution of the hot strip (60) to be output from the finishing mill (30).

10. Verfahren nach Anspruch 9, gekennzeichnet durch die folgen- the procedural steps: - Ermitteln (S211) einer Walzgeschwindigkeit, mit der the preliminary strip (50) is rolled in the finishing mill (30); and Page 29 / 32 P80921WO - Berechnen (S221) der Soll-Temperaturverteilung des Pre-strip (50) before entering the finishing mill (30) based on the rolling speed in the finishing mill (30).

11. Verfahren nach einem der Ansprüche 6 bis 10, gekennzeichnet through the following procedural steps: - Ermitteln (S212) einer Vorwalzdauer, innerhalb der das metallic rolling stock (40) is pre-rolled in the pre-rolling mill (10) to form the pre-strip (50); - Berechnen (S222) der Soll-Temperaturverteilung des Pre-strip (50) before entering the finishing mill (30) under the condition that a pre-strip (50) having the target temperature distribution can be finish-rolled in the finishing mill (30) to hot strip (60) within a finish-rolling time that corresponds to the pre-rolling time.

12. Verfahren nach einem der vorhergehenden Ansprüche, gekenn-is characterized by the following features: - das Verfahren weist einen Verfahrensschritt zum Ermit- parts (S11) of a geometric deviation of a pre-strip (50) output from the roughing mill (10) from a desired geometry of the pre-strip (50); and - das Kühlen (S24) des Vorbandes (50) erfolgt unter Be- taking into account the geometric deviation of the pre-strip (50) in such a way that a top side (53) and a bottom side (54) of the pre-strip (50) are subjected to cooling fluid in such a way that targeted mechanical stresses are induced in the pre-strip (50), which cause a deformation of the pre-strip (50) in the direction of the desired geometry.

13. Verfahren nach einem der vorhergehenden Ansprüche, gekenn- is characterized by the following features: Page 30 / 32 P80921WO - das Verfahren weist einen Verfahrensschritt zum Ermit- parts (S12) of a temperature distribution of the pre-strip (50) output from the roughing mill (10) in the width direction (B) of the pre-strip (50); and - basierend auf der ermittelten Temperaturverteilung inWidth extension (B) Cooling (S25) of the pre-strip (50) by means of the pre-strip cooler (20) such that the pre-strip (50) output from the pre-strip cooler (20) has a temperature distribution along its width extension (B) which is symmetrical with respect to a longitudinal axis (L) of the pre-strip (50).

14. Verfahren nach einem der vorhergehenden Ansprüche, gekenn- is characterized by the following features: - Ermitteln (S13) einer Breitenausdehnung des Vorbandes (50); and - Steuern (S26) der Kühlfluiddüsen (21) derart, dass this cooling fluid is only released onto the pre-strip (50).

15. Computerprogrammprodukt umfassend Programmcode-Mittel ge- suitable for carrying out the steps of a method according to one of the preceding claims when the computer program product is executed on a computing device (80).

16. Warmbandstraße (100) zur Herstellung eines Warmbandes (60), with - einem Vorwalzwerk (10) zur Annahme eines metallischen rolling stock (40) and for outputting a pre-strip (50); - einem Fertigwalzwerk (30) zur Aufnahme eines Vorbandes (50) and for outputting a hot strip (60); - einen Vorbandkühler (20), welcher zwischen dem Vor- rolling mill (10) and the finishing mill (30) and is designed to pass a pre-strip (50) through Page 31 / 32 P80921WO Applying a cooling fluid dispensed via a plurality of individually or in groups controllable cooling fluid nozzles (21) to cool; - eine Steuerungseinrichtung (80), die mit dem Vorband- cooler (20) is data-coupled for outputting control signals, wherein the hot strip mill (100) is characterized in that the hot strip mill (100) is designed to carry out one of the methods according to one of claims 1 to 14.

17. Warmbandstraße (100) nach Anspruch 16, aufweisend zumindest a temperature detection device (70) which is arranged between an output of the roughing mill (10) and an input of the pre-strip cooler (20) and is designed to determine a temperature of the pre-strip output from the roughing mill (10), wherein the hot strip mill (100) is characterized in that the hot strip mill (100) is designed to carry out the method according to claim 6.

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