Energy-efficient production of rolled products with a large final thickness

Abstract

The invention relates to a method (100a, 100b) for operating a casting and rolling plant (10). According to the method (100a, 100b), a continuous strand (12) is produced (102) by means of casting. The continuous strand (12) is fed (104) to a first roll stand group (14). In an operating state of a first type (118), a portion (16) is separated (106) from said continuous strand (12) after passing through the first roll stand group (14), preferably by means of pendulum shears (18). The portion (16) separated from the continuous strand (12) is then fed (108) to another roll stand group (20) for processing. Furthermore, the portion (16) separated from the continuous strand (12) is accelerated (110) between the first roll stand group (14) and the other roll stand group (20).

Description

[0001] Description

[0002] Energy-efficient production of rolled products with high final thickness

[0003] field of technology

[0004] The invention relates to a method for operating a casting and rolling plant and to a casting and rolling plant.

[0005] State of the art

[0006] Already known casting-rolling mills make it possible to produce a rolled product with an uninterrupted material flow from a casting device to a finishing rolling stand group. This operating mode of a casting-rolling mill is therefore referred to as continuous operation. After passing through the finishing rolling group, the rolled product is usually fed to a cooling section and then wound up as a so-called coil. As soon as a maximum capacity, such as a predetermined weight or diameter, of such a coil is reached, the material flow is interrupted by a separating device. A major advantage of this operating mode is its potential for energy savings. Furthermore, mechanical stress on components of the casting-rolling mill can be minimized, for example, by avoiding contact shocks from a first rolling device.This enables high product quality, a long service life, and a low failure probability. However, the energy efficiency of continuous operation decreases with increasing final thickness of a rolled product. The increasing final thickness of a rolled product leads to a reduced throughput speed at a constant material flow. The resulting temperature losses must be compensated for by heating. Furthermore, this can lead to increased scale formation and / or undesirable microstructural changes. Furthermore, the exit speed of the rolled product from the finishing stand group decreases with increasing final thickness. Depending on the final thickness and strength of the rolled product, a low exit speed can therefore lead to problems when coiling the finished rolled product.Furthermore, in the case of a low exit velocity, there is a risk that a target structure will be missed or at least partially undesired structural transformations will occur due to a cooling process starting too late.

[0007] DE 102008 003222 A1 discloses a compact, flexible CSP plant for continuous, semi-continuous, and batch operation, comprising a casting machine, a roughing stand group, and a finishing stand group. For batch or semi-continuous operation, a coil storage unit is integrated into the roller table to store the preliminary strip or slab coming from the roughing stand. In the case of continuous operation, the coil storage unit is deactivated. The disadvantage is the additional space required for the coil storage unit and the associated temperature loss in the rolled stock. Due to the aforementioned disadvantages of increasing final thickness in continuous operation, the material flow outgoing from the casting device is often interrupted before rolling. This operating mode is usually referred to as batch operation. The disadvantage of this operating mode is that it is associated with greater mechanical loads on components of the casting and rolling plant.However, this allows a rolling speed to be decoupled from the material flow speed specified by the casting device. This allows high exit speeds of a finished rolled product to be achieved.

[0008] In addition, rolled products with higher final thickness and / or increased strength can be coiled with low risk.

[0009] Summary of the invention

[0010] The object of the present invention is to optimize the energy efficiency of a casting-rolling plant as a function of the final thickness and / or strength of the rolled product. In particular, the object of the present invention is to provide the kinetic energy required for coiling in the form of a sufficient exit speed of a finished rolled product.

[0011] These objects are achieved by a method for operating a casting and rolling plant having the features of independent claim 1.

[0012] Furthermore, these objects are achieved by a casting and rolling plant having the features of the subordinate claim.

[0013] Advantageous further training is the subject of dependent subclaims.

[0014] The method according to the invention for operating a casting and rolling mill is particularly advantageous for a casting and rolling mill that has a hot rolling train. In the method according to the invention for operating a casting and rolling mill, a continuous strand is produced by casting. This continuous strand is fed to a first rolling stand group. This first rolling stand group is preferably a roughing stand group, which in English is often referred to as a "high reduction mill" (HRM). In a first type of operating state, a section is severed from said continuous strand after it has passed through the first rolling stand group. Preferably, said section is severed by means of a separating device, which is particularly preferably designed as a pendulum shear. The section severed from the continuous strand is then fed to a further rolling stand group for processing.The additional rolling stand group is preferably a finishing rolling stand group. This typically represents the final section of the casting-rolling mill before coiling. In English, this is often referred to as a "finishing mill" (FM). Furthermore, the method according to the invention for operating the casting-rolling mill provides for the section separated from the endless strand to be accelerated between the first rolling stand group and the additional rolling stand group. In the present context, "accelerating" should be understood to mean increasing the speed of the section separated from the endless strand between the first rolling stand group and the additional rolling stand group.

[0015] Cutting off a section of the endless strand after the first rolling stand group makes it possible to combine the advantages of a casting-rolling plant in continuous operation with those of a casting-rolling plant in batch operation. For example, continuous operation can be used to avoid pass-through impacts and achieve a greater reduction in the thickness of the rolled product, while still meeting specified gripping conditions. Furthermore, this can decouple the throughput speed of the cut-off section from the speed determined by a material flow emanating from a casting device. In addition, the disadvantages of continuous operation, which arise with increasing final thicknesses or high strengths of the rolled product, can be minimized or even overcome by accelerating the cut-off section between the first rolling stand group and the subsequent rolling stand group.For example, temperature loss due to low throughput speed or scale formation can be counteracted. A microstructural transformation that leads to a structure that deviates from the target structure can be prevented in this way. In particular, a premature microstructural transformation from an austenite structure to an austenite-ferrite structure can be counteracted before the rolled product reaches the cooling section. Furthermore, the acceleration of the section severed from the endless strand ensures that a finished rolled product has sufficiently high kinetic energy for coiling upon exiting a finishing rolling stand group. This allows rolled products that have a conventional strength, for example with a thickness of 10 mm or more, to be manufactured and coiled in a safe and energy-saving manner.

[0016] In an advantageous development, the section severed from the endless strand is accelerated before it reaches the further rolling stand group. Preferably, said section is accelerated before it reaches a cleaning device upstream of the further rolling stand group. The cleaning device is preferably a descaling device. In the context of the present invention, a rolling stand group or the cleaning device is reached as soon as a head part of the severed section enters this rolling stand group or this cleaning device. As a result, a temperature loss caused by operation of the cleaning device can be kept to a minimum. Furthermore, a section severed from the endless strip can be accelerated in a controlled manner before entering a further rolling stand group or the cleaning device.The cut section can therefore be reliably and precisely accelerated to the required entry speed before entering this rolling stand group. As a result, the exit speed from the subsequent rolling stand group can be easily adjusted to a final thickness and the minimum kinetic energy required for coiling. The energy requirements of the casting-rolling plant can thus be optimized.

[0017] A further advantageous development provides that the said section is severed from the endless strand before the endless strand reaches the further rolling stand group. Preferably, the said section is severed from the endless strand before the endless strand reaches a cleaning device upstream of the further rolling stand group. In the present context, the fact that the endless strand reaches the further rolling stand group or the cleaning device should be understood to mean that a head portion of the endless strand enters the rolling stand group or the cleaning device. Separating between the first and the further rolling stand group makes it possible to prevent bulging at a foot or head portion of the severed section upon exiting the first rolling stand group. This can reduce malfunctions and interruptions in the operation of the casting and rolling plant. The casting and rolling plant can therefore be operated reliably and efficiently.Furthermore, the quality of rolled products to be manufactured can be improved.

[0018] Preferably, after the section severed from the continuous strand enters the additional rolling stand group, a constant speed of a portion of said section entering this rolling stand group is maintained. Acceleration by the additional rolling stand group can be dispensed with. This has a positive effect on product quality. Furthermore, deceleration of the severed section can be dispensed with.

[0019] A constant final rolling temperature is advantageously achieved by controlling or regulating the temperature of the part of the cut-off section entering the next rolling stand group using a heating device. Temperature differences between the head and foot sections of the cut-off section can be easily and reliably compensated in this way. This allows for high quality with a uniform microstructure to be achieved.

[0020] In an alternative advantageous development, it is provided that after the section severed from the endless strand enters the further rolling stand group, a speed of the part of the severed section of the endless strand entering said rolling stand group is changed by means of the further rolling stand group. By means of a subsequent speed change, temperature differences between a head region and a foot region of the severed section can be taken into account. This makes it possible to control a constant final rolling temperature based on a change in the speed of the entering part of the severed section. In a preferred application, the energy expenditure for adjusting temperature differences between the head region and foot region of the severed section can be kept low or even eliminated. This makes it possible to reduce energy requirements.Energy efficiency can therefore be increased in a simple way.

[0021] An advantageous embodiment provides for a constant final rolling temperature to be achieved by reducing the speed of the part of the separated section entering the further rolling stand group by means of the further rolling stand group. This allows for simple and energy-saving control of the final rolling temperature. A temperature difference between a more rapidly cooled head section and a less rapidly cooled foot section of the separated section can thus be compensated.

[0022] Preferably, a second type of operating mode is provided. In the second type of operating mode, the continuous strand produced by casting is continuously fed to the next roll stand group after passing through the first roll stand group. In this way, continuous operation can still be selected for operation of the casting-rolling plant in the case of thin rolled products or rolled products with low strength. However, as soon as an increase in the final thickness of a rolled product to be produced leads to suboptimal energy consumption or problems when coiling the rolled product, the first type of operating mode can be selected for operation of the casting-rolling plant. This allows the advantages of continuous casting-rolling operation to be flexibly combined with the advantages of discontinuous casting-rolling operation as required.Furthermore, in this way, a sufficiently high kinetic energy of an emerging finished rolled product can be provided for the purpose of coiling.

[0023] Preferably, in the first operating mode, the severed section of the endless strand and / or in the second operating mode, the uninterrupted endless strand passes through a temperature-maintaining device on its way between the first rolling stand group and the further rolling stand group. In the present context, the temperature-maintaining device is understood to mean a device which counteracts cooling by radiant heat or convection. For example, the temperature-maintaining device can be designed as an insulated tunnel, on the inside of which thermal radiation is preferably reflected and / or thermal radiation is absorbed and then re-radiated. In this way, a long conveying distance between the first rolling stand group and the further rolling stand group can be realized.In a preferred embodiment, the conveyor line has a length of at least 40 m, preferably at least 80 m, and particularly preferably at least 120 m. Temperature losses during transport along such an extended conveyor line can be minimized using the temperature control device. Furthermore, the length of the section severed from the continuous strand can be selected depending on the reel capacity.

[0024] In a further advantageous development, it is provided that in the first operating mode, the section severed from the continuous strand and / or in the second operating mode, the uninterrupted continuous strand between the first rolling stand group and the further rolling stand group is heated. Temperature losses can thus be reliably compensated in both operating modes. Furthermore, special quality requirements can be met. In the case of a linear acceleration of the severed section, the thermal power for heating purposes is also increased linearly.

[0025] In an advantageous embodiment, in the first operating mode, the section separated from the continuous strand and / or in the second operating mode, the uninterrupted continuous strand between the first rolling stand group and the further rolling stand group is heated inductively, electrically, and / or by gas firing. This allows the temperature of a rolled product to be manufactured to be easily and reliably controlled or regulated. Hydrogen is preferably used as the fuel in the aforementioned gas firing.

[0026] The method according to the invention can be carried out by means of the casting and rolling plant according to the invention.

[0027] The casting and rolling mill according to the invention comprises a continuous casting device for casting a continuous strand. Furthermore, the casting and rolling mill comprises a first rolling stand group and a cutting device arranged downstream of the first rolling stand group. Advantageously, the cutting device is designed as a pendulum shear. By means of the cutting device, a section can be cut off from the continuous strand. Furthermore, a further rolling stand group is provided, which is arranged downstream of the first rolling stand group and the aforementioned cutting device. Furthermore, a conveyor line is provided, which connects the first rolling stand group to the further rolling stand group. An acceleration device is also provided along the conveyor line, by means of which the speed of the section cut off from the continuous strand can be varied before it reaches the further rolling stand group.The casting and rolling plant according to the invention is preferably a single-strand casting and rolling plant, which particularly preferably has a hot rolling mill.

[0028] The first rolling stand group is expediently designed as a roughing stand group. The further rolling stand group is preferably designed as a finishing roll stand group. Downstream of the further rolling stand group, a receiving device for a finished rolled product is usually provided. If the severed section is accelerated in such a way that a sufficient distance is achieved between said section and a subsequent section, the casting and rolling mill can be operated with only one receiving device. For safety reasons, however, it is customary to provide two receiving devices. The receiving device is often at least one coiler, onto which the rolled product is coiled by bending.To avoid having to interrupt the casting process in the event of a fault, a discharge device, often referred to as a pusher-piler, with an associated separating device can be provided along the conveyor line. Furthermore, the casting-rolling plant can have a cleaning device for removing scale, which is preferably arranged along the conveyor line.

[0029] The casting-rolling mill enables the method for operating the casting-rolling mill to be carried out efficiently and reliably. Depending on the final thickness of a rolled product to be produced, the casting-rolling mill can be operated either in the previously described first-type operating mode or in the previously described second-type operating mode. Furthermore, a casting-rolling mill can be provided that can produce a wide variety of final thicknesses with optimized energy consumption. Furthermore, this makes it possible to decouple the speed of the severed section from the speed of the endless strip specified by the continuous casting device. By accelerating this section, it is easy to reduce temperature loss with increasing final thickness, minimize scale formation, and prevent microstructures that deviate from the target microstructure.

[0030] An advantageous development of the casting-rolling plant provides that the conveyor line has a length of at least 40 m. Preferably, the conveyor line has a length of at least 80 m, and particularly preferably at least 120 m. The length of the sections cut from the endless strip can be easily adapted to a coiler capacity. Furthermore, this makes it possible to continue to provide the necessary kinetic energy for reliably winding the finished rolled product onto a coiler as the final thickness of a rolled product to be produced increases.

[0031] The first roll stand group and the further roll stand group are expediently arranged as directly consecutive roll stand groups. In the present context, the arrangement of said roll stand groups in directly consecutive order means that no further roll stand group is provided between the said roll stand groups. However, other components of the casting and rolling plant, such as a separating device, a discharge device, a heating device, or the like, can be provided between the roll stand groups arranged directly consecutively. This makes it possible to further increase the energy efficiency and cost-effectiveness of the plant. Temperature losses can be kept to a minimum.

[0032] Preferably, a temperature-maintaining device is provided along at least one section of the conveyor line for the purpose of thermally shielding the endless strand or the section severed from the endless strand. The temperature-maintaining device mentioned is, in particular, the temperature-maintaining device already explained above in connection with the method. Expediently, a heating device is arranged along at least one further section of the conveyor line, by means of which heating device a temperature of the endless strand or of the severed section of the endless strand can be controlled or regulated. As a result, the section severed from the endless strand can be heated in a simple manner in the first type of operating state and / or the uninterrupted endless strand between the first rolling stand group and the further rolling stand group in the second type of operating state.The heating device mentioned is advantageously designed to heat the continuous strand or the section separated from the continuous strand inductively, by gas firing, and / or by thermal radiation. This allows the temperature of the rolled product to be produced to be controlled or regulated in an energy-efficient and reliable manner.

[0033] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of exemplary embodiments, which is explained in more detail in conjunction with the figures. The figures are schematic, not to scale, drawings. They show:

[0034] FIG 1 shows an embodiment of a casting and rolling plant according to the invention;

[0035] FIG 2 shows an illustration of a first example of a method for operating the casting and rolling plant according to the invention using a schematic flow diagram;

[0036] FIG 3 shows an illustration of a second example of a method for operating the casting and rolling plant according to the invention using a schematic flow diagram.

[0037] Where appropriate, the same reference numerals are used in the figures for the same or corresponding elements of the invention.

[0038] Description of the embodiments

[0039] Figure 1 shows an embodiment of a casting and rolling plant 10 in a schematic representation.

[0040] The exemplary embodiment of the casting and rolling mill 10 has a continuous casting device 28. In this case, an endless strand 12 is cast by means of the continuous casting device 28. Furthermore, the casting and rolling mill 10 has a first rolling stand group 14. This is designed, for example, as a roughing stand group. The endless strand 12 produced by the continuous casting device 28 is rolled for the first time in the first rolling stand group 14. Downstream 30 of the first rolling stand group 14 is a cutting device 18, by means of which a section 16 can be severed from the endless strand 12. This cutting device 18 is designed, for example, as a pendulum shear. Furthermore, a further rolling stand group 20 is provided, which is arranged downstream 30 of the first rolling stand group 14 and the cutting device 18. By way of example, the further rolling stand group 20 is designed as a finishing rolling stand group.

[0041] Furthermore, a conveyor line 32 is provided between the first roll stand group 14 and the further roll stand group 20. This conveyor line connects the first roll stand group 14 to the further roll stand group 20. A discharge device 38, which comprises a drum shear, is arranged along this conveyor line 32 downstream 30 of the separating device 18, for example. Furthermore, a temperature-maintaining device 26, an acceleration device 36, a cleaning device 22, and a heating device 24 are arranged along this conveyor line 32, for example. The sequence and position of the aforementioned components or of other components that may be required for the operation of the casting-rolling plant 10 can be rearranged as needed. For example, the first roll stand group 14 and the further roll stand group 20 are directly connected to one another by means of the conveyor line 32.In the present context, this means that no further roll stand group is provided between the two roll stand groups 14, 20. Downstream 30 of the further roll stand group 20, a cooling section (not shown in detail) and two receiving devices 34 are provided, for example. The cooling section can be designed, for example, as a strip cooling device, as a laminar cooling device, as a pressure cooling device, or a combination thereof. Each of the receiving devices 34 is designed, for example, as a reel. A finished rolled product is wound onto each of the reels by bending until a predetermined maximum capacity, such as a predetermined weight or a predetermined diameter, is reached. Between the further roll stand group 20 and the two receiving devices 34, a further separating device 18 is provided, for example.This can be designed, for example, as a pendulum shear, drum shear, or crank shear, which can also be designed as a high-speed shear or as a start / stop shear. This allows an endless strand 12 or a section 16 severed therefrom to be severed if the maximum capacity of one of the two receiving devices 34 is reached or in the event of a fault.

[0042] In the present case, the conveyor line 32 has a length of at least 100 m, for example. This allows a section 16 severed from the endless strand 12 to leave the additional rolling stand group 20 with sufficiently high kinetic energy by means of the aforementioned acceleration device 36 for the purpose of coiling, and also allows the length of the section to be matched to a maximum capacity of the receiving device 34. Operation of the aforementioned additional separation device 18 can therefore generally be dispensed with. Furthermore, temperature losses during transport of the aforementioned section 16 along the conveyor line 32 can be kept to a minimum with the aid of the aforementioned temperature-maintaining device 26. The temperature-maintaining device 26 is designed, for example, as an insulated tunnel (not shown in detail), the interior of which reflects and / or absorbs thermal radiation and then re-radiates it.In this way, heat losses during transport of the section 16 along the conveyor line 32 can be kept small.

[0043] Figure 2 illustrates a first example of a method 100a for operating a casting-rolling plant 10. The casting-rolling plant 10 is, in particular, the casting-rolling plant 10 described in connection with Figure 1.

[0044] The first example of the method 100a provides that a continuous strand 12 is produced 102 by casting. In the present case, this is produced 102, for example, using the continuous casting device 28. The continuous strand 12 is then fed 104 to the first rolling stand group 14 of the casting and rolling mill 10.

[0045] In a first type operating state 118, a section 16 is severed 106 from said endless strand 12 after passing through the first rolling stand group 14. This makes it possible to decouple a throughput speed of the severed section 16 from a speed of the endless strand 12 predetermined by a material flow of the continuous casting device 28. Such a decoupling is particularly advantageous in order to achieve high kinetic energy of the rolled product when the rolled product exits the further rolling stand group 20, even with a high strength and / or final thickness of the rolled product. This kinetic energy is necessary in order to reliably transfer a finished rolled product to the receiving device 34 by bending.For this purpose, in the presently described example of the method 100a, in the first type of operating state 118, the aforementioned section 16 is severed 106 from the endless strand 12 before the endless strand 12 reaches the further rolling stand group 20. Particularly advantageously, the aforementioned section 16 is severed 106 from the endless strand 12 before the endless strand 12 reaches a cleaning device 22 upstream of the further rolling stand group 20. This makes it possible to convey the section 16 severed from the endless strand 12 through the cleaning device 22 at an increased speed, thereby minimizing any temperature loss due to cleaning. Furthermore, the section 16 severed from the endless strand 12 can thus be accelerated 110 in a simple and reliable manner between the first rolling stand group 14 and the further rolling stand group 20 to a predeterminable speed.For thin rolled products and / or rolled products with low strength, it is possible to operate the casting-rolling mill 10 in a second operating mode 120. In this case, the kinetic energy required for coiling can be provided based on the speed of the continuous strand 12 determined by the material flow of the continuous casting device 28. In contrast to the first operating mode 118, in the second operating mode 120, the continuous strand 12 is continuously fed 108 to the further rolling stand group 20.

[0046] In order to achieve the acceleration 110 of the section 16 severed from the endless strip 12, a conveyor line 32 connecting the first rolling stand group 14 and the further rolling stand group 20 is preferably greater than 100 m. In order to minimize temperature losses during transport along this extended conveyor line 32, the presently described first example of the method 100a provides that the section 16 severed from the endless strand 12 and / or the uninterrupted endless strand 12 passes through 122 the temperature-maintaining device 26 arranged along the conveyor line 32. Furthermore, it is provided, by way of example, that said section 16 and / or said uninterrupted endless strand 12 is heated 124 by means of an inductive and / or electrical heating device 24 along at least a section of the conveyor line 32.Furthermore, the heating device 24 can alternatively or additionally be designed as a gas firing device, in which combustible gas, in particular hydrogen, is burned for the purpose of heating 124 the aforementioned section 16 and / or the aforementioned continuous strand 12. This can counteract temperature loss, undesired scale formation, and undesired structural changes.

[0047] Furthermore, in the first example of the method 100a, it is provided that after the section 16 severed from the endless strand 12 enters the further rolling stand group 20, a constant speed of the part of said section 16 entering this rolling stand group 20 is maintained 112. It is provided that a constant final rolling temperature is achieved by controlling or regulating a temperature of the part of said severed section 16 entering the further rolling stand group 20 by means of the heating device 24 114.In the second type of operating state 120, due to the uninterrupted endless strip 12 and the thus predetermined constant speed of the part of the endless strip 12 entering the further rolling stand group 20, it is provided that a constant final rolling temperature is achieved by controlling or regulating a temperature of the part of the endless strip 12 entering this rolling stand group 20 by means of the heating device 24 114.

[0048] Figure 3 illustrates a second example of a method 100b for operating a casting and rolling mill 10. The casting and rolling mill 10 is, in particular, the casting and rolling mill 10 described in connection with Figure 1. In contrast to the first example of the method 100a described in connection with Figure 2, in the second example of the method 100b it is provided that after the section 16 severed from the endless strand 12 enters the further rolling stand group 20, a speed of the part of the severed section 16 entering the said rolling stand group 20 is changed 116 by means of the further rolling stand group 20. In this way, both a final rolling temperature and an exit speed can be controlled in a cost-effective manner.In this context, a constant final rolling temperature is preferably achieved by reducing 116 the speed of that part of the separated section 16 entering the further rolling stand group 20 by means of the further rolling stand group 20. In this way, a temperature difference between a head region and a less cooled root region can be easily compensated. In a particular embodiment of the second example of the method 100b described here, the heating 124 by means of the heating device 24 described in connection with Figure 1 can therefore be completely or partially dispensed with. This allows energy consumption to be optimized and energy efficiency to be increased during operation of the casting-rolling mill 10.

[0049] If necessary, the portion of the section 16 separated from the continuous strand 12 entering the further rolling stand group 20 can still be heated 124 by the heating device 24 after passing 122 through the temperature-maintaining device 26. Energy losses due to transport along the extended conveyor line 32 can be easily compensated. This can counteract structural changes or surface scaling.

[0050] Using the previously described examples of methods 100a, 100b, the described embodiment of the casting-rolling plant 10 can advantageously produce rolled products with a final thickness of 0.8 mm to 32 mm, a target width of 600 mm to 3000 mm, and a thickness of the endless strip 12 of 70 mm to 250 mm provided by the continuous casting device 28. This allows a maximum weight of one of the support devices 34 of 60 t or a maximum specific weight of the support device 34 of 25 kg / mm ​​to be achieved.

[0051] Although the invention has been illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention.

[0052] 10 Casting and rolling plant

[0053] 12 endless strands

[0054] 14 first rolling stand group

[0055] Section 16

[0056] 18 Cutting device / pendulum shears

[0057] 20 additional rolling stand groups

[0058] 22 Cleaning device

[0059] 24 Heating device

[0060] 26 Temperature holding device

[0061] 28 Continuous casting device

[0062] 30 downstream

[0063] 32 conveyor line

[0064] 34 Mounting device

[0065] 36 Accelerator

[0066] 38 Discharge device

[0067] 100a, 100b Procedure

[0068] 102 Create endless strand

[0069] 104 feed to first rolling stand group

[0070] 106 separate

[0071] 108 add to another rolling stand group

[0072] accelerate to 110

[0073] 112 Maintain speed

[0074] 114 Control or regulate temperature

[0075] 116 Change / decrease speed

[0076] 118 Operating condition of the first kind

[0077] 120 Second type operating condition

[0078] 122 Pass through temperature maintenance device

[0079] 124 heat

Claims

Claims 1. A method (100a, 100b) for operating a casting-rolling plant (10), in which a continuous strand (12) is produced by casting (102); the continuous strand (12) is fed (104) to a first rolling stand group (14); in a first type of operating state (118), a section (16) is severed (106) from said continuous strand (12) after passing through the first rolling stand group (14), preferably by means of a pendulum shear (18); the section (16) severed from the continuous strand (12) is fed (108) to a further rolling stand group (20) for processing; characterized in that the section (16) severed from the continuous strand (12) is accelerated (110) between the first rolling stand group (14) and the further rolling stand group (20).

2. Method (100a, 100b) according to claim 1, wherein the section (16) severed from the endless strand (12) is accelerated (110) before it reaches the further rolling stand group (20), preferably before it reaches a cleaning device (22) upstream of the further rolling stand group (20).

3. Method (100a, 100b) according to claim 1 or 2, wherein said section (16) is severed (106) from the endless strand (12) before the endless strand (12) reaches the further rolling stand group (20) or preferably before the endless strand (12) reaches a cleaning device (22) upstream of the further rolling stand group (20).

4. Method (100a) according to one of the preceding claims, in which, after the section (16) separated from the endless strand (12) enters the further rolling stand group (20), a constant speed of the part of said section (16) entering this rolling stand group (20) is maintained (112).

5. Method (100a) according to claim 4, wherein a constant final rolling temperature is achieved by controlling or regulating (114) a temperature of the part of said separated section (16) entering the further rolling stand group (20) by means of a heating device (24).

6. Method (100b) according to one of claims 1 to 3, wherein after the section (16) separated from the endless strand (12) enters the further rolling stand group (20), a speed of the section (16) entering the said rolling stand group (20) entering part of said severed section (16) of the endless strand (12) is changed (116) by means of the further rolling stand group (20).

7. The method (100b) according to claim 6, wherein a constant final rolling temperature is achieved by reducing (116) a speed of the part of said severed section (16) entering the further rolling stand group (20) by means of the further rolling stand group (20).

8. Method (100a, 100b) according to one of the preceding claims, in which, in an operating state of the second type (120), the continuous strand (12) produced by casting is continuously fed (108) to the further roll stand group (20) after passing through the first roll stand group (14).

9. Method (100a, 100b) according to one of the preceding claims, in which in the first type of operating state (118) the severed section (16) of the endless strand (12) and / or in the second type of operating state (120) the uninterrupted endless strand (12) passes through a temperature-maintaining device (26) between the first rolling stand group (14) and the further rolling stand group (20) (122).

10. Method (100a, 100b) according to one of the preceding claims, in which in the first type operating state (118) the section (16) severed from the endless strand (12) and / or in the second type operating state (120) the uninterrupted endless strand (12) is heated (124) between the first rolling stand group (14) and the further rolling stand group (20).

11. Method (100a, 100b) according to claim 10, wherein in the first type operating state (118) the section (16) severed from the endless strand (12) and / or in the second type operating state (120) the uninterrupted endless strand (12) between the first rolling stand group (14) and the further rolling stand group (20) is heated inductively, electrically and / or by means of gas firing (124).

12. Casting and rolling plant (10) for carrying out the method (100a, 100b) according to one of the preceding claims, comprising: a continuous casting device (28) for casting a continuous strand (12); a first rolling stand group (14); a separating device (18) which is arranged downstream (30) of the first rolling stand group (14) and by means of which a section (16) can be separated from the continuous strand (12); a further rolling stand group (20) which is arranged downstream (30) of the first rolling stand group (14) and of the separating device (18); a conveyor line (32) connecting the first rolling stand group (14) to the further rolling stand group (20); characterized in that an acceleration device (36) is provided along the conveyor line (32), by means of which a speed of the section (16) severed from the endless strand (12) can be varied before reaching the further rolling stand group (20).

13. Casting and rolling plant (10) according to claim 12, characterized in that the conveyor line (32) has a length of at least 40 m, preferably at least 80 m and particularly preferably at least 120 m.

14. Casting and rolling plant (10) according to claim 12 or 13, characterized in that the first rolling stand group (14) and the further rolling stand group (20) are arranged as directly successive rolling stand groups.

15. Casting and rolling plant (10) according to one of claims 12 to 14, characterized in that a temperature-maintaining device (26) for the purpose of thermally shielding the endless strand (12) or the section (16) severed from the endless strand (12) is provided along at least one section (16) of the conveyor line (32); a heating device (24) is provided along at least one further section (16) of the conveyor line (32), by means of which heating device a temperature of the endless strand (12) or of the severed section (16) of the endless strand (12) can be controlled.

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