EP2162557B1 - Process for hot rolling and for heat treatment of a steel strip - Google Patents

Abstract

The invention relates to a process for hot rolling and for heat treatment of a strip (1) of steel. To make it possible to produce high-strength and very high-strength strips having satisfactory toughnesses more economically in a continuous production plant, the process provides the steps: a) heating of the slab to be rolled; b) rolling of the slab to the desired strip thickness; c) cooling of the strip (1), with the strip (1) having a temperature above ambient temperature (T0) after cooling; d) rolling up of the strip (1) to produce a coil (2); e) rolling off of the strip (1) from the coil (2); f) heating of the strip (1); g) cooling of the strip (1) and h) transport of the strip (1) to a further destination, with the strip (1) having a temperature above ambient temperature (T0) before heating as per step T).

Description

The invention relates to a method for hot rolling and for heat treating a strip of steel.

Hardening and subsequent tempering of steel components is common practice. This ensures that a desired combination of strength and toughness of the material can be adjusted specifically. This technology is also used in principle in the production of higher-strength steel sheets in sheet metal plants. It is in the EP 1 764 423 A1 described. Here, after the heating of the slab and the rolling down to the final thickness on the plate mill in several reversing passes the sheet is cooled at high speed, for example to room temperature, ie it is the hardening process completed. This is followed by the annealing process, ie the reheating of the strip to, for example, 600 ° C, followed by another cooling. In this way, sheets with different properties can be produced flexibly in small batches in a sheet metal frame.

Similar methods are known from JP 04 358022 A , from the JP 04 358023 A and from the JP 58 009919 A known.

As in the field of sheet metal production, the demand for steel grades with very high strength is constantly increasing in strip production as well. H. the demand for so-called high-strength and ultra-high-strength steels. These materials are used, inter alia, in motor vehicles, cranes, containers and pipes.

The present invention is therefore based on the object to provide a method by which a more economical production of high and very high-strength tapes with sufficient toughness in a belt system is possible. In particular, it should therefore be possible to produce QT steels in an advantageous manner.

1. a) Erwärmen der zu walzenden Bramme;
2. b) Walzen der Bramme auf die gewünschte Banddicke;
3. c) Kühlen des Bandes, wobei das Band nach dem Kühlen in der Regel eine über der Umgebungstemperatur liegende Temperatur aufweist;
4. d) Aufhaspeln des Bandes zu einem Coil;
5. e) Abhaspeln des Bandes vom Coil;
6. f) Erhitzen des Bandes;
7. g) Kühlen des Bandes und
8. h) Abtransport des Bandes,

wobei das Band vor der Erwärmung gemäß Schritt f) eine über der Umgebungstemperatur liegende Temperatur aufweist und wobei das Coil bei der Durchführung des Schritts d) an einer Aufhaspelstation befindet und dass sich das Coil bei der Durchführung des Schritts e) an einer von der Aufhaspelstation räumlich entfernten Abhaspelstation befindet, wobei das Coil zwischen Schritt d) und e) wärmeisoliert von der Aufhaspelstation zur Abhaspelstation transportiert wird.The solution of this object by the invention is characterized in that the method comprises the steps of:

1. a) heating the slab to be rolled;
2. b) rolling the slab to the desired strip thickness;
3. c) cooling the belt, wherein the belt after cooling generally has a temperature above the ambient temperature;
4. d) coiling the tape into a coil;
5. e) unwinding the tape from the coil;
6. f) heating the tape;
7. g) cooling the tape and
8. h) removal of the tape,

wherein the strip has a temperature above ambient temperature prior to heating in step f), and wherein the coil is at a coiling station when step d) is performed, and that the coil spatially rests at one of the coiling station when step e) is performed distant unwinding station, wherein the coil between step d) and e) is heat-insulated transported from the coiling station to Abhaspelstation.

Step e) can be immediately followed by step d).

The belt may be subjected to a straightening process during cooling or after cooling after step c) and / or step g). It can also be subjected to a straightening process between the uncoiling after step e) and the heating after step f). It may also be subjected to a straightening process between the heating after step f) and the removal after step h). The straightening process mentioned can be done by deflecting the belt around ground, deflection, driving or other roles.

The straightening process is generally carried out with a roller straightening machine or employed band deflection rollers or, according to a special embodiment of the invention, on a so-called skin-pass framework.

The tape may also be subjected to a straightening process during the heating of the above step f).

The cooling of the belt after step c) may comprise laminar cooling and subsequent intensive cooling. Cooling the tape after step g) may also include laminar cooling or, alternatively or additively, air cooling.

At least parts of the cooling device can be designed as zone cooling, which act zone-wise over the bandwidth.

The cooling of the belt can also be done with a high-pressure beam, whereby a simultaneous cleaning or descaling of the belt is possible.

The heating of the strip according to step f) may comprise inductive heating. In this case, alternatively, a direct flame impingement of the strip can take place. In the latter case, it is preferably provided that the direct application of flame to the strip takes place by means of a gas jet with at least 75% oxygen, preferably with almost pure oxygen, into which a gaseous or liquid fuel is mixed.

A further development provides that the inductive heating of the strip takes place under inert gas (protective gas).

The removal of the tape after step h) may comprise a winding of the tape. The removal of the tape after step h) may also include a pushing off of plate-like cut parts of the tape.

The strip preferably has a temperature of at least 750 ° C. before cooling after step c).

It preferably has a temperature of at least 25 ° C and at most 400 ° C, preferably between 100 ° C and 300 ° C after cooling after step c) and before the coiling after step d).

Furthermore, a further development provides that the strip after heating after step f) has a temperature of at least 400 ° C., preferably between 400 ° C. and 700 ° C. However, after cooling after step g) and before removal after step h), the strip may preferably have a temperature of at most 200 ° C, preferably between 25 ° C and 200 ° C.

The heating of the tape can be done differently over the bandwidth.

Finally, it can be provided that the steps e) to g) are carried out in reversing operation, for which purpose a coiling station located behind the cooling after step g) is used.

Furthermore, it can be provided that the planarity of the strip and / or the temperature of the strip (the latter preferably by means of a temperature scanner) is measured at at least two locations of the strip treatment plant for monitoring the quality of the strip.

The throughput speed of the belt through the belt treatment plant, in particular zone-related belt heating, the adjustment of the straightening rollers and / or the particular zone-related belt cooling can be controlled or regulated by a process model.

Finally, when passing through the strip treatment plant, the strip can be held at least in sections by means of drivers under a defined strip tension. This is especially true in the area of the intensive cooling section.

In order to ensure a centric running in of the tape in the driver, in the roller straightening unit or in the intensive cooling, a band side guide is preferably arranged in front of it.

1. a) Erwärmen der zu walzenden Bramme;
2. b) Walzen der Bramme auf die gewünschte Banddicke;
3. c) Kühlen des Bandes, wobei das Band nach dem Kühlen eine über der Umgebungstemperatur liegende Temperatur aufweist;
4. d) Aufhaspeln des Bandes auf einem ersten Haspel;
5. e) Reversieren des Bandes zwischen dem ersten Haspel und einem zweiten Haspel, wobei das Band zwischen den Haspeln einer Erhitzung zwecks Durchführung eines Anlassvorgangs unterzogen wird,

wobei das Band vor der Erwärmung gemäß Schritt e) eine über der Umgebungstemperatur liegende Temperatur aufweist.An alternative embodiment of the method for hot rolling and heat treating a strip of steel comprises the steps of:

1. a) heating the slab to be rolled;
2. b) rolling the slab to the desired strip thickness;
3. c) cooling the tape, the tape having a temperature above ambient temperature after cooling;
4. d) coiling the tape on a first reel;
5. e) reversing the tape between the first reel and a second reel, the tape between the reels being subjected to heating for the purpose of performing a tempering operation,

wherein the strip has a temperature above ambient temperature prior to heating in step e).

This method can also be combined with the above-mentioned embodiments.

The following training courses have continued to prove themselves:

Before and behind the cooling of the tape, a tape tension can be built up by means of a driver.

The band can be guided by means of a lateral guide transversely to its longitudinal axis. The lateral guidance can preferably take place in the region of the cooling of the belt, in particular in the area of the laminar cooling of the belt.

The side guide of the tape can also be done in front of the driver and open after passing the tape head and close again at the end of the tape for the purpose of leadership task.

A measurement of the strip temperature can be carried out by means of a low-temperature radiation pyrometer. The measurement of the strip temperature can preferably take place before, inside and / or behind temperature-variable cooling and / or heating devices.

The production spectrum of a hot strip mill differs considerably from that of a heavy plate mill. Thus, there is a large number of newly developed high-strength and ultra-high-strength steel grades during the last decades, whose properties can be adjusted by specific rolling and / or cooling strategies. A suitable method for this, after rolling, is to quench the strip at a high cooling rate, followed by reheating to temperatures below the phase transition temperature.

The classical QT steels (Q: quenched, T: tempered) that can be produced in this way are already being produced on heavy-plate stands. However, they can be produced much more economically in hot strip mills.

Furthermore, on hot strip mills and thinner high-strength tapes with lower temperature and thickness tolerance and flat flatness can be generated safely. It is therefore useful and advantageous to shift production shares of heavy plate stands on strip lines.

In addition, there are many new types of steel that are not produced on heavy plate stands. For the group of multiphase steels, the method presented here is particularly suitable. By means of a significantly enlarged spectrum of temperature-time curves and in particular by means of the possibility of interrupting the cooling and temporarily increasing the temperature again, it is possible to produce microstructures with virtually any combination of phase components which can not be produced at present. In addition, it is possible to run elimination operations and thus introduce targeted second phases, which are a characteristic of modern steel grades.

Furthermore, the process presented can set properties for which higher alloy contents are necessary in conventional production.

It is advantageous in the separate arrangement of the rolling and cooling process on the one hand and the annealing process on the other hand, the flexibility of the process (no mixed-rolling necessary), the flexible adjustment of the temperature-time curve of the tape and that own coils or coils are processed by other facilities can. Coils or plates may also be cut, depending on the purpose of the tape or the windability. The cutting of the plates is preferably carried out at a higher temperature, d. H. especially at tempering temperature.

It is advantageous in the coupled arrangement of the rolling and cooling process and the annealing process, the particularly large energy savings, difficult to be coiled and to be bound coils, the use of a special reel with direct transfer to avoid the so-called. Clock spring problem. Furthermore, there is a fast further processing or delivery of the belts for direct further processing. Finally, the greater possibility of influencing the microstructure of the band in the mentioned arrangements should be mentioned.

Fig. 1

schematisch eine Warmbandstraße für die Herstellung eines Stahlbandes gemäß einer ersten Ausführungsform der Erfindung,

Fig. 2

eine zu Fig. 1 alternative Ausgestaltung der Warmbandstraße (nicht gemäß der Erfindung),

Fig. 3

einen exemplarischen Temperaturverlauf (nicht gemäß der Erfindung) des Bandes über der Förderrichtung der Warmbandstraße,

Fig.4

als Ausschnitt aus der Warmbandstraße gemäß Fig. 1 oder 2 den prinzipiellen Aufbau einer Richtmaschine mit integrierter Intensivkühlung,

Fig. 5

als Ausschnitt aus der Warmbandstraße gemäß Fig. 1 oder 2 den prinzipiellen Aufbau einer Richtmaschine mit integrierter Heizung und

Fig. 6

schematisch eine Warmbandstraße mit einer alternativen Ausgestaltung einer ersten Verfahrensstufe.

In the drawings, embodiments of the invention are shown. Show it:

Fig. 1

1 schematically shows a hot strip mill for the production of a steel strip according to a first embodiment of the invention,

Fig. 2

one too Fig. 1 alternative embodiment of the hot strip mill (not according to the invention),

Fig. 3

an exemplary temperature profile (not according to the invention) of the strip over the conveying direction of the hot strip mill,

Figure 4

as a section of the hot strip mill according to Fig. 1 or 2 the basic structure of a straightening machine with integrated intensive cooling,

Fig. 5

as a section of the hot strip mill according to Fig. 1 or 2 the basic structure of a straightening machine with integrated heating and

Fig. 6

schematically a hot strip mill with an alternative embodiment of a first process stage.

In Fig. 1 a hot strip mill is shown, in which a band 1 first in a first process stage (indicated by l.) And then in a second process stage (indicated by II.) Is processed.

In the first process stage, ie in a rolling and cooling process, a slab is first rolled in a multi-stand rolling mill. Shown are from the Walzstraße only the last three finishing stands 7, which have rolled the band 6 with an intermediate thickness. Following this, the temperature distribution in the strip or the flatness can be measured. Subsequently, the belt 1 passes in the conveying direction F in a belt cooling 8, which is here from an intensive laminar belt cooling 9 with so-called. Edge Masking and a laminar belt cooling 10 divided. The conveying speed is for example 6 m / s. Subsequently, the cooled strip 1 passes into an intensive cooling 11, in which according to a preferred embodiment of the invention, a straightening machine and driver are integrated (details in this Fig. 4 ). It can be provided before and behind the intensive cooling 11 drivers.

Subsequent to the intensive cooling 11, a measurement of the temperature distribution and the flatness of the strip can again follow. Preferably, a low-temperature radiation pyrometer is used at these low temperatures. Within intensive cooling, a temperature measurement is conceivable between two pinch rolls or driver rolls for the purpose of temperature / coolant control.

Then the tape 1 is reeled in a Aufhaspelstation 3 by a reel 12 or 13.

Then the coil 2 enters the 2nd process stage, d. H. in the starting process.

Here, the coil 2 is first unwound in a unwinding station 4 and then fed to a straightening machine 14 (this can be arranged in front of and / or behind the adjoining oven). After a temperature compensation over the length and width of the tape has taken place in a zone 15, the tape 1 enters an oven 16. It is possible and advantageous to integrate into the oven 16 analogous to the cooling of a straightening machine (for details see Fig. 5 ). Here, the belt 1 can be heated in continuous or reverse operation. Preferably comes an oxyfuel furnace or an induction furnace is used, the heating time is between 10 and 600 seconds.

This is followed by a trimming scissors 17 and a pair of scissors 18. Subsequently, the strip 1 enters a laminar belt cooling or, alternatively, an air cooling system 19. This can be followed by a straightening machine 20. In Fig. 1 is then still a Plattenabschiebeeinheit 21 and a reel 22 indicated in a Aufhaspelstation 5.

Instead of a straightening machine 14 or 20, a skin-pass scaffold can also be arranged here.

Coils from other hot strip mills can also be introduced at the location of the unwinding station 4.

In contrast, a non-inventive direct connection of the two process stages I. and II. In Fig. 2 to see (the plant is not shown fully equipped). Analogously, the last stands of a hot strip mill (finishing line 7), the belt cooling 8 and the reels 12 and 13 of the 1st process stage are shown here. The last reel 23 is provided for winding the higher strength belts. This may advantageously be a special reel for easy winding of high-strength steels. The reel 23 is in this case a so-called transfer reel. The coil does not need to be bound there. Pivoting pinch rollers hold the tape under tension as it is rotated to the unwind position. Immediately after winding, therefore, the further processing takes place in the starting line (2nd process stage). The further transport takes place analogously as in the solution according to Fig. 1 ,

Particularly advantageous here are the energy savings in bands higher winding temperature and the rapid onward transport of the coils from the 1st to the 2nd stage of the process. Namely, it is provided that the band 1 before heating in the oven 16 already has a temperature above the ambient temperature T ₀ .

In addition, a reversal of the band between the two reels 23 and 22 is also possible for special tapes to perform desired temperature gradients or treatments of the band can.

A temperature profile for the belt 1 along the belt line is corresponding to Fig. 2 in Fig. 3 played. The cooling to the end of the line is preferably a water or air cooling.

However, a cooling can also be done with a high pressure bar. This is carried out at the same time a cleaning or descaling of the strip surface. The production amount of the rolling mill is usually higher than during the tempering process, since the rolling speed of the strip is greater than the starting speed. It is therefore also a so-called. Mixed Rolling rolling operation possible to optimally utilize the rolling mill. This means that a number of ribbons are wound on reels 12 and 13 while the further processing of the higher strength ribbon occurs in the tempering line.

According to the invention, the production of the strip is thus essentially divided into two process stages, which are given below by way of example with further optional steps:

1st stage of the process:

• Heating slabs (thick or thin slabs) and then rolling in a multistage hot strip mill;
• Intensive cooling of the belt on the outfeed roller table;
• Pass through a leveler;
• Wrap the ribbon to a coil.

To improve the flatness of the high-strength tapes, strip edge heaters in front of a conventional finishing line, edge masking in the first cooling line units, and a straightening machine are advantageous.

At higher winding temperatures, a fast coil transport to the subsequent 2nd process stage is advantageous to save heating energy when starting. The transport of the coils can then be done under a heat-insulating hood to reduce the loss of temperature and to ensure more uniform material properties.

2nd stage of the process:

• Unwinding the coil,
• In case of unevenness, optional straightening of the strip in a straightening machine;
• Optionally balancing the strip temperature by zone cooling or heating prior to the actual tempering treatment to even out the strip temperature over the strip length and width;
• Starting the tape, d. H. continuous reheating with an induction heating or energetically advantageous in a gas-heated continuous furnace (eg oxy-fuel furnace with the so-called DFI method);
• Trimming the ribbon;
• Subsequent cooling of the tape;
• Redirecting the tape;
• Rewinding the tape into a coil.

Alternatively, the bands can be cut into sheets in front of the oven, behind the oven and / or immediately before the sheet removal unit. The cutting of panels is particularly advantageous in difficult to be wound tapes. Cutting at tempering temperature is advantageous because the strip has a lower strength there.

For thicker strips and / or high strength steels that can no longer be cut, a flame cutting machine, a laser cutting machine or a thermal cutting machine is provided for cutting.

This is the oxyfuel furnace in which the so-called DFI oxyfuel process (direct flame application) is carried out for tempering It is a special furnace where (almost) pure oxygen instead of air and gaseous or liquid fuel are mixed and the resulting flame is aimed directly at the belt. This not only optimizes the firing process, but also reduces nitrogen oxide emissions. The scaling properties are also favorable or the growth of scale is very low (operate with low air). The high flow rate of the gases even has a cleaning effect on the strip surface. With regard to strip surface quality, this type of heating is particularly advantageous. With this method similar high heat densities can be achieved with good efficiency, as in inductive heating.

Instead of a consecutively arranged cooling section and inline straightening machine in the 1st or 2nd process stage, the straightening machine and the belt cooling can also be accommodated in a combined unit. The straightening rollers are then used simultaneously as water squeezing rollers and thus ensure as uniform a cooling effect as possible over the width of the belt, because possible transverse strains and unevenness are eliminated directly during formation. The adjustment of the straightening rollers is done individually depending on the belt temperature and the material quality with the support of a straightening machine model, so that overstretching of the belt surface can be avoided. Drivers in front of and behind the cooling drafting unit ensure that the strip pulls as long as possible, even if the scaffolding or the coiler has not been erected. Part of the strip cooling may be in the form of a strip zone cooling in order to be able to actively influence the temperature distribution. The cooling-straightening unit is in the FIGS. 1 and 2 indicated. Details on this go out Fig. 4 out. In this figure, any possible combinations for straightening, cooling and squeezing can be seen. For the safe threading process of the tape head, the cooling-straightening unit is designed to be raised and swiveled, especially in thinner tape, which also in Fig. 4 is indicated (see double arrow). The straightening rollers are individually adjustable.

Before and / or behind the in Fig. 4 see joint arrangement of straightener and cooling a temperature scanner for the band can be provided. In front of the illustrated system, a tape head shape detector (for detecting a ski or waves) may be positioned.

In detail to be recognized in Fig. 4 Driver 24, a pure cooling units 25, straightening rollers 26 and combined pinch rollers / drivers 27. Furthermore, nozzles of the intensive cooling 28 can be seen.

It is an alternate arrangement of cooling, straightening and driving roller units possible. The directing amount is set individually depending on the material of the tape and the temperature. The straightening and cooling unit can be lifted and swiveled.

As in Fig. 5 can be seen, also the straightening and heating process 14, 16 of the second process stage combined with the system shown can be driven. Similarly, the indicative amount can be adjusted to the existing strip temperature and the strip material. The effect of the skin effect (higher surface temperature) of the induction heating (or a direct application of flame in the DFI oxyfuel process) has a positive effect. At the same time, the straightening rollers keep the belt in position and avoid unevenness, so that the most efficient (inductive) heating in the long filet part of the belt is possible. Driver 29 in front of and behind the heating-straightening unit keep the tape under tensile stress 30. For the safe threading of the tape head, the induction coils 32 and straightening and transfer rollers 31 are designed to be vertically adjustable.

The use of the cooling-straightening unit ( Fig. 4 ) or the heating-straightening unit ( Fig. 5 ) is not limited to a belt system, but can also be provided in a heavy plate plant.

Before and / or behind the in Fig. 5 To see common arrangement of leveler and heater, a temperature scanner for the band can be provided.

In order to influence the temperature distribution over the bandwidth in the 2nd stage of the process of inductive heating, u. a. Querfeldinduktoren used, which can be moved transversely to the direction of tape travel or conveying direction F. Hereby, if necessary, for example, the band edges are heated more or heated less intense.

Optionally, prior to heating the belt to tempering temperature, balancing the belt temperature across the length and width of the belt may be accomplished by selective cooling (zone cooling) or heating to warm or cold belt sections. This should be provided in particular, if not completely cooled to ambient temperature coils should be treated. As a result, the passage of the coils can be shortened by the Coillager. A coil tracking system (model) and the measured temperature distributions during unwinding of the coil are used to optimally control the heating or cooling units.

For the straightening rollers, job-welded high-wear roller materials are used to ensure a long service life and good strip quality.

Temperature scanners and flatness measuring devices within the line indirectly monitor the quality of the strip and serve as a signal for actuators and control elements, such. For example, for the flow rate, the heating power, the straightening roller adjustment and the cooling, which are controlled by a process model.

In Fig. 6 the first process step is shown in a somewhat modified embodiment. Analogous to Fig. 1 shows Fig. 6 the rear part of the finishing train 7, laminar belt cooling units 9, 10 and an intensive cooling 11 and the Aufhaspelstationen 3. In this embodiment, the intensive cooling 11 and a band straightening unit 36.1, 36.2 are arranged at different locations. Before and behind the intensive cooling 11 drivers 34 and 35 are positioned. This makes it possible to maintain a strip tension within the intensive cooling 11 almost for the entire strip length, without the strip being clamped in the frame or coiler. This will be pulled out possibly occurring tape shafts, thus achieving the most uniform cooling effect.

In order to ensure a centric running in of the tape in the driver 34, 35 or / and in the intensive cooling 11, a band side guide 33.1 is arranged in front of it in a particularly advantageous manner. After the tape head has passed the driver 33.1 and the intensive cooling 11, the side guide 33.1 is opened again, so that the water flow in the laminar belt cooling 10 is not hindered. The leadership task then takes over the leadership of the rest of the band 33.2. Analogously, the guide 33.1 is briefly made again for the end of the tape after the end has left the finishing line to counteract a running of the tape end. Therefore, in order to minimize the cooling path length, the side guide 33. 1 is preferably arranged within the laminar belt cooling unit 10.

The straightening rollers 36.1, 36.2 before each Aufhaspelstationen 3 are immersed in the band level after construction of the strip tension and ensure by wrapping the bottom, deflection or drive rollers for a band straightening effect. A similar mode of operation is practiced if, within the intensive cooling section 11 deflection rollers 26 (s. Fig. 4 ) are arranged.

LIST OF REFERENCE NUMBERS

1

Band (behind the finishing train with final thickness)

2

coil

3

coiling

4

uncoiling

5

coiling

6

Strip (within the finishing mill with intermediate thickness)

7

finishing line

8th

strip cooling

9

intensive laminar band cooling

10

laminar band cooling

11

intensive cooling

12

reel

13

reel

14

straightener

15

Zone

16

oven

17

trimming shears

18

scissors

19

Air cooling or laminar belt cooling

20

straightener

21

plate pushing

22

reel

23

reel

24

driver

25

pure cooling unit

26

straightening roller

27

Squeezing roller / driver

28

Nozzles of intensive cooling

29

driver

30

tension

31

Überleitrolle

32

induction coil

33.1

Side guide before the first driver / before the intensive cooling

33.2

Side guide in front of the reel driver

34

Driver before the intensive cooling

35

Driver behind the intensive cooling

36.1

Straightening roller before the first winding station

36.2

Straightening roller in front of the second winding station

I.

1st stage of the process

II.

2nd stage of the process

F

conveying direction

T ₀

ambient temperature

Claims (36)

1. Method for hot rolling and for heat treatment of a strip (1) of steel, comprising the steps:

   initially performing the following steps a) to d) within the scope of a rolling and cooling process:

   a) heating the slab to be rolled;

   b) rolling the slab to the desired strip thickness;

   c) cooling the strip (1), wherein after the cooling the strip (1) has a temperature above the ambient temperature (To);

   d) coiling the strip (1) into a coil (2);

   subsequently performing the following steps e) to h) within the scope of a tempering process:

   e) uncoiling the strip from the coil (2);

   f) heating the strip (1);

   g) cooling the strip (1) and

   h) transporting the strip (1) away,

   wherein before the heating according to step f) the strip (1) has a temperature above the ambient temperature (T₀) and wherein when the step d) is performed the coil (2) is located at a coiling station (3) and that when the step e) is performed the coil (2) is located at an uncoiling station (4) spatially remote from the coiling station (3), wherein the coil (2) is transported from the coiling station (3) to the uncoiling station (4) between steps d) and e) in a thermally insulated manner.
2. Method according to claim 1, characterised in that step e) of claim 1 directly follows step d) of claim 1.
3. Method according to claim 1 or 2, characterised in that during cooling or after cooling according to step c) and/or according to step g) of claim 1 the strip (1) is subjected to a straightening process.
4. Method according to any one of claims 1 to 4, characterised in that between the uncoiling according to step e) of claim 1 and the heating according to step f) of claim 1 the strip (1) is subjected to a straightening process.
5. Method according to any one of claims 1 to 4, characterised in that between the heating according to step f) of claim 1 and the transport away according to step h) of claim 1 the step (1) is subjected to a straightening process.
6. Method according to any one of claims 3 to 5, characterised in that the straightening process is effected by deflecting the strip (1) around base, deflecting, driving or other rollers.
7. Method according to any one of claims 4 to 6, characterised in that the straightening process is carried out by means of a skin-pass stand.
8. Method according to any one of claims 1 to 7, characterised in that the strip (1) is subjected to a straightening process during the heating according to step f) of claim 1.
9. Method according to any one of claims 1 to 8, characterised in that the cooling of the strip (1) according to step c) of claim 1 comprises a laminar cooling and intensive coolings.
10. Method according to any one of claims 1 to 9, characterised in that the cooling of the strip (1) according to step g) of claim 1 comprises a laminar cooling.
11. Method according to any one of claims 1 to 10, characterised in that the cooling of the strip (1) according to step c) and/or according to step g) of claim 1 takes place zonally over the width of the strip.
12. Method according to any one of claims 1 to 11, characterised in that the cooling of the strip (1) according to step g) of claim 1 comprises air cooling.
13. Method according to one of claims 1 to 12, characterised in that the cooling of the strip (1) according to step g) of claim 1 is carried by means of a high-pressure bar so that cleaning and/or descaling of the strip takes or take place at the same time.
14. Method according to any one of claims 1 to 13, characterised in that the heating of the strip (1) according to step f) of claim 1 comprises inductive heating.
15. Method according to claim 14, characterised in that the inductive heating of the strip (1) takes place in an inert gas atmosphere.
16. Method according to any one of claim 1 to 13, characterised in that the heating of the strip (1) according to step f) of claim 1 is effected by direct flame action on the strip.
17. Method according to claim 16, characterised in that the direct flame action on the strip (1) is effected by a gas jet comprising at least 75% oxygen in which a gaseous or liquid fuel is mixed.
18. Method according to claim 17, characterised in that the direct flame action is effected by a gas jet comprising pure oxygen.
19. Method according to any one of claims 1 to 18, characterised in that the transport away of the strip (1) according to step h) of claim 1 comprises coiling the strip (1).
20. Method according to any one of claims 1 to 18, characterised in that the transport away of the strip (1) according to step h) of claim 1 comprises pushing off plate-like cut portions of the strip (1).
21. Method according to any one of claims 1 to 20, characterised in that before the cooling according to step c) of claim 1 the strip (1) has a temperature of at least 750° C.
22. Method according to any one of claims 1 to 21, characterised in that the cooling according to step c) of claim 1 and before coiling according to step d) of claim 1 the strip (1) has a temperature of at least 25° C and at most 400° C, preferably between 100° C and 300° C.
23. Method according to any one of claims 1 to 22, characterised in that after the heating according to step f) of claim 1, the strip (1) has a temperature of at least 400° C, preferably between 400° C and 700° C.
24. Method according to any one of claims 1 to 23, characterised in that the heating of the strip (1) according to step f) of claim 1 is carried out in such a manner that the strip has different temperatures over its width.
25. Method according to any one of claims 1 to 24, characterised in that after the cooling according to step g) of claim 1 and before transport away according to step h) of claim 1 the strip (1) has a temperature of at most 200° C, preferably between 25° C and 200° C.
26. Method according to any one of claims 1 to 25, characterised in that the steps e) to g) of claim 1 are carried out in reversing operation, for which purpose a coiling station (5) located behind the cooling according to step g) of claim 1 is used.
27. Method according to any one of claims 1 to 26, characterised in that the flatness of the strip (1) and/or the temperature of the strip (1) is or are measured at at least two locations in the strip treatment plant for monitoring the quality of the strip (1).
28. Method according to any one of claims 1 to 27, characterised in that the transit speed of the strip through the strip treatment plant, the in particular, zone-related strip heating, the adjustment of the straightening rolls and/or the, in particular, zone-related cooling are controlled or regulated by a process model.
29. Method according to any one of claims 1 to 28, characterised in that during passage through the strip treatment plant the strip (1) is held under a defined strip tension at least in sections by means of drivers.
30. Method according to any one of claims 1 to 29, characterised in that a strip tension is built up by means of drivers (34, 35) before and after the cooling of the strip (1).
31. Method according to any one of claims 1 to 30, characterised in that a strip (1) is guided transversely to its longitudinal axis by means of a lateral guidance (33.1, 33.2).
32. Method according to claim 31, characterised in that the lateral guidance (33.1, 33.2) takes place in the region of the cooling of the strip (1).
33. Method according to claim 32, characterised in that the lateral guidance (33.1, 33.2) takes place in the region of the laminar cooling of the strip (1).
34. Method according to claim 30 and any one of claims 31 to 33, characterised in that the lateral guidance (33.1, 33.2) of the strip (1) takes place in front of the driver (34, 35) and opens after passing the strip head and closes at the strip end.
35. Method according to any one of claims 1 to 34, characterised in that a measurement of the strip temperature is carried out by means of a low-temperature radiation pyrometer.
36. Method according to any one of claims 1 to 35, characterised in that a measurement of the strip temperature is carried out in front of, within and/or behind the cooling and/or heating devices.

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