VERTICAL OVEN FOR CONTINUOUS HEAT TREATMENT OF A METAL STRIP

Description

[0001] The invention relates to a vertical furnace for the continuous heat treatment of a metal strip according to the preamble of claim 1.

[0002] Vertical furnaces for heat treating strips are known in the art. As the strip is transported vertically, it is heated to the treatment temperature and then annealed. The strip is then cooled and returned to the vertical conveying direction using a deflector.

[0003] A disadvantage of state-of-the-art vertical furnaces is that the strips often suffer damage in the deflection area after heating, heat treatment, and cooling processes due to thermal stresses and strains, their own weight, and additional stress caused by the deflection. This can lead to a reduction in strip quality and surface finish. Relevant furnaces are known from US 2006 / 037679 A1, US 4363471 A, and EP2960348A1.

[0004] The object of the present invention was to overcome the disadvantages of the prior art and to provide a device by means of which an improved quality of metal strips can be ensured.

[0005] This object is achieved according to the invention with a vertical furnace of the type mentioned at the outset by the features of the characterizing part of claim 1. The design according to the invention has the advantage that a metal strip can be deflected at a moderate temperature and only cooled to the target temperature after the deflection and the damage in the area of ​​the deflection device can be considerably reduced.

[0006] An additional advantage of this design is that the height of the vertical furnace can be better utilized, since not all heating and cooling devices are arranged in front of the deflection device.

[0007] Advantageous further training is listed in the subclaims.

[0008] It is particularly advantageous that the vertical furnace has a protective gas atmosphere with a high H2 content (30% - 100% H2) (vol.%) and low dew points (-20°C to -70°C) in the heating / holding zone, in the first cooling zone, in the deflection device, and in the second cooling zone for heat treatment of the metal strip in order to prevent oxidation. It has proven particularly advantageous that the entire heat treatment of the metal strip, in particular of the electrical steel strip, takes place in a protective gas atmosphere with a high H2 content (30% - 100% H2) (vol.%) and low dew points (-20°C to -70°C) in order to prevent oxidation.

[0009] The furnace for the vertical heat treatment of metal strip, especially electrical steel strip, can comprise one or more heating stations, which can be insulated with a heat-insulating material, and a single- or multi-part annealing chamber (with or without a muffle) filled with a high-H2 protective gas atmosphere. The heating and / or holding zone can be heated by electrical energy (electric heating elements and / or induction heating) or by gas heating.

[0010] One or more cooling zones can be arranged next to the strip, which can be connected to a gas supply unit. This is followed by an upper roller chamber, in which two guide rollers can be arranged, which guide the moving metal strip and direct it back into a vertical outlet chute.

[0011] It has been found to be particularly advantageous that the heating / holding zone and the first cooling zone each comprise at least one process chamber with an inlet opening and an outlet opening for the metal strip, in particular a metal-encapsulated process chamber, for example at least one process chamber surrounded by a muffle.

[0012] In order to prevent the escape of protective gas, the process space of the heating / holding zone is advantageously connected to the process space of the first cooling zone in a gas-tight manner.

[0013] It should also be noted at this point that the invention is not limited to vertical furnaces with muffles, but also encompasses all other types of vertical furnaces, such as brick-lined furnaces. Slow cooling of the metal strip is made possible by the fact that the first cooling zone is designed as a radiation cooling zone for the metal strip.

[0014] A cooling / heating chamber through which a cooling fluid flows is arranged around the process chamber of the first cooling zone. A surface of a wall surrounding the process chamber facing the cooling / heating chamber is exposed to the cooling fluid. Advantageously, the fluid is a gas or gas mixture, in particular air.

[0015] To recover energy and cool the cooling fluid, at least one heat exchanger can be provided to transfer heat from the cooling fluid to another material stream. This variant of the invention is particularly suitable for a circulating cooling fluid.

[0016] Alternatively or additionally, at least one supply line for supplying fresh cooling fluid, in particular fresh air, can be provided.

[0017] In order to be able to adjust the amount of cooling fluid, at least one discharge line for expelling cooling fluid flowing out of the cooling / heating chamber from the vertical furnace may also be provided.

[0018] To generate a flow in the cooling fluid, at least one turbo machine, for example a fan, can be provided.

[0019] In order to be able to adjust the temperature of the cooling fluid better, at least one heating device can be provided for heating the cooling fluid.

[0020] It has proven particularly advantageous that at least one temperature measuring device is arranged to measure the temperature in the cooling-heating chamber.

[0021] In order to detect the temperatures in the cooling fluid, at least one temperature measuring device for measuring the temperature of the cooling fluid flowing out of the cooling / heating chamber and at least one temperature measurement for measuring the cooling medium flowing into the cooling / heating chamber can be provided.

[0022] An optimal process sequence can be achieved by the vertical furnace being designed to change the temperature of the cooling medium flowing into the cooling / heating chamber as a function of at least one temperature measured in the cooling / heating chamber and / or the flow velocity of the cooling medium.

[0023] Furthermore, at least one pressure measuring device for measuring a pressure in the cooling / heating chamber can be arranged in the cooling / heating chamber.

[0024] Advantageously, the at least one second cooling zone can comprise at least one spray and / or nozzle cooling and / or jet cooling for applying cooling fluid to a surface of the metal strip.

[0025] In order not to adversely affect the protective gas atmosphere in the second cooling zone, the cooling fluid of the at least one second cooling zone may comprise or be a protective gas, in particular H 2 .

[0026] In a preferred embodiment of the invention, it is provided that the first cooling zone and the second cooling zone are connected to one another in a gas-tight manner at their ends facing the deflection device via a housing of the deflection device with respect to the environment of the vertical furnace.

[0027] To prevent the metal strip from cooling down too much during deflection, the deflection device can be thermally insulated.

[0028] It has proven particularly advantageous that the deflection device comprises at least one heating means.

[0029] According to a preferred variant of the invention, which has proven to be particularly advantageous with regard to damage-free deflection, it is provided that the deflection device comprises a temperature measuring unit and a temperature control unit, wherein the temperature control unit is designed to regulate a temperature level of the deflection device to a temperature level of the metal strip by means of the at least one heating means.

[0030] In order to be able to optimally adjust the running of the metal strip, at least one roller arrangement of the deflection device can be used for center control.

[0031] In order to increase the process speed, the vertical furnace can have an additional rapid heating zone for the metal strip with at least one heating device in the conveying direction of the metal strip before the heating zone and / or holding zone.

[0032] A variant of the invention, which is characterized by very rapid heating of the metal strip, consists in that the at least one heating device of the rapid heating zone is designed as an induction heater, wherein the rapid heating zone comprises a process chamber with a wall made of a non-metallic material and an inlet and an outlet opening for the metal strip, wherein the process chamber of the rapid heating zone has a protective gas atmosphere with a high H 2 content of 30% - 100% H 2 (vol.%) and low dew points of -20°C to -70°C, and the induction heater is arranged outside the process chamber.

[0033] Advantageously, the process space of the rapid heating zone is connected to the process space of the heating / holding zone in a gas-tight manner with respect to the external environment of the vertical furnace.

[0034] According to an advantageous development of the invention, a third cooling zone can be provided, which third cooling zone is arranged after the second cooling zone with respect to the conveying direction of the metal strip, wherein the third cooling zone has a protective gas atmosphere with high H 2 content (30% - 100% H 2 ) (vol.%) and low dew points (-20°C to -70°C).

[0035] In order to ensure optimal guidance of the metal strip, it can be provided that at least one dancer roller mounted in a housing is arranged in the inlet zone and / or in the outlet zone, wherein the housing has an inlet and outlet opening for the metal strip.

[0036] Furthermore, it has proven particularly advantageous that a protective gas atmosphere, in particular a hydrogen and / or nitrogen atmosphere, prevails in the interior of the housing.

[0037] In order to prevent gas from escaping from the inlet side of the vertical furnace, it can be provided that the inlet zone is connected to the rapid heating zone in a gas-tight manner with respect to the environment of the vertical furnace.

[0038] An outlet-side gas leak can be prevented by connecting the outlet zone to a downward branch of the vertical furnace comprising at least the second cooling zone in a gas-tight manner with respect to the environment of the vertical furnace.

[0039] For a better understanding of the invention, it is explained in more detail with reference to the following figures, which relate to non-limiting embodiments.

[0040] They show in a highly simplified, schematic representation: Fig. 1 shows a vertical furnace according to the invention; Fig. 2 shows a section through an inlet area of ​​the vertical furnace; Fig. 3 shows a section along the line III-III in Fig. 1; Fig. 4 the first cooling zone in more detail; Fig. 5 a section along the line VV in Fig. 4 .

[0041] By way of introduction, it should be noted that in the variously described embodiments, identical parts are provided with identical reference symbols or component designations. The disclosures contained throughout the description can be applied analogously to identical parts with identical reference symbols or component designations. Furthermore, the positional information chosen in the description, such as top, bottom, side, etc., refers to the directly described and illustrated figure, and these positional information must be applied analogously to the new position in the event of a change in position.

[0042] The characters are described comprehensively below.

[0043] According to Fig. 1A vertical furnace 1 for the continuous heat treatment of a metal strip 2 can have, viewed in a conveying direction of the metal strip 2, an inlet zone 3 for the metal strip 2, a heating / holding zone 4 comprising an annealing chamber for heating and maintaining the temperature of the metal strip 2, a first cooling zone 5 for slowly cooling the metal strip 2, and a deflection device 6 arranged downstream of the first cooling zone 5, comprising a roller arrangement 7 with two or more rollers, for deflecting the metal strip 2 in the direction of an outlet zone 8 for the metal strip 2. An embodiment of the heating / holding zone 4 and the first cooling zone 5 are described in more detail below.

[0044] Downstream of the deflection device 6 is a second cooling zone 9, wherein the second cooling zone 9 comprises at least one cooling fluid supply unit. The cooling fluid supply unit serves to feed a cooling fluid, for example a gas or a cooling liquid, into the second cooling zone 9 for cooling the metal strip 2. The cooling fluid supply unit can, for example, comprise spray and / or nozzle cooling and / or jet cooling. For example, nozzles can be arranged in the second cooling zone 9 through which the cooling fluid is blown to flow around the metal strip 2 in the second cooling zone 9. The cooling of the metal strip 2 in the second cooling zone 9 preferably takes place by convection. The first cooling zone 5, on the other hand, is designed as a radiation cooling zone, in which the cooling of the metal strip 2 takes place by emitting radiation. The cooling fluid can be circulated in the second cooling zone 9.In this case, a heat exchanger can also be provided to transfer heat from the cooling fluid to another material stream. For example, the cooling fluid can be extracted from the second cooling zone and fed to the heat exchanger via a line. After cooling, it can be blown back into the second cooling zone 9.

[0045] The heat treatment of the metal strip takes place in a protective gas atmosphere with a high H2 content (30% - 100% H2) and low dew points (-20°C to -70°C) to prevent oxidation. For this reason, a protective gas atmosphere is present in the heating / holding zone 4, the first cooling zone 5, the deflection device 6, the second cooling zone 9, and any subsequent cooling zones. In particular, a protective gas atmosphere can be present throughout the entire ascending and descending sections.

[0046] In order not to contaminate the protective gas atmosphere inside the vertical furnace 1, a protective gas, in particular a protective gas comprising H 2, can be used as the cooling fluid in the cooling zone 9.

[0047] A third cooling zone 11 can be provided adjacent to the second cooling zone 9. What has been said about cooling zone 9 also applies to cooling zone 11. The cooling of the metal strip 2 takes place to varying degrees in the three cooling zones 5, 9 and 11. A difference between the inlet temperature of the metal strip 2 into the respective cooling zone 5, 9, 11 and the outlet temperature when leaving the respective cooling zone 5, 9, 11 is preferably higher in the first cooling zone 5 than in the second cooling zone 9 and in the third cooling zone 11. In the first cooling zone 5, the metal strip 2 can be cooled, for example, from 1020°C to 700°, in the second cooling zone 9 from 700°C to 600°C and in the third cooling zone 11 from 600°C to 60°C. The values ​​given above are examples and can vary in practice.

[0048] In the deflection device 6, the temperature can be constant compared to the first cooling zone 5. As can be seen from Fig. 1As can be seen, the deflection device 6 or the roller arrangement 7 can reverse the conveying direction of the metal strip 2 in the second cooling zone 9 compared to the first cooling zone 5. In particular, the deflection device 6 or the roller arrangement 7 can deflect the conveying direction of the metal strip by 180°.

[0049] The first cooling zone 5 and the second cooling zone 9 are connected to one another at their ends facing the deflection device 6 via a housing 10 of the deflection device 9 in a gas-tight manner with respect to the surroundings of the vertical furnace 1. The cooling zone 5 and the cooling zone 9 can also be fluidly connected or gas-connected to one another via the housing 10. Thus, the first cooling zone 5 and the second cooling zone 9, as well as the housing 10 of the deflection device, form a common space. The deflection device 9 also represents a gas-connection between an upward branch 17 comprising the heating / holding zone 4 and the first cooling zone 5, and a downward branch 18 of the vertical furnace 1 comprising the cooling zone 9 and optionally further cooling zones.

[0050] The deflection device 6 can be thermally insulated and comprise one or more heating means and a temperature control unit to enable adjustment and / or regulation of the temperature of the deflection device 6. The heating means of the deflection device can be electrically or gas-powered. The deflection of the metal strip 2 takes place at an elevated temperature between 300°C and 1000°C. The temperature control unit is configured to regulate a temperature level of the deflection device 9 to a temperature level of the metal strip 2 by means of the at least one heating means. By means of the deflection device, the metal strip 2 is deflected without damage at an elevated strip temperature and in a purest protective gas atmosphere with a hydrogen content between 30% and 100% and a dew point between -20°C and -70°C.

[0051] Furthermore, the roller arrangement 7 of the deflection device 6 can have center-controlled deflection rollers in order to center the metal strip.

[0052] A rapid heating zone 12 with a heating device can be arranged upstream of the heating / holding zone 4. The heating device of the rapid heating zone 12 is preferably designed as an induction heater and serves to quickly heat the metal strip 2. The rapid heating zone 12 has a process chamber with a wall made of a non-metallic material and an inlet and an outlet opening for the metal strip. The process chamber can be realized with a muffle. The process chamber of the rapid heating zone 12 contains a protective gas atmosphere with a high H2 content of 30% - 100% H2 and low dew points of -20°C to -70°C. At least one inductor is arranged outside the process chamber of the rapid heating zone 12. The process chamber can be enclosed by the inductor. The inductor can be designed as a transverse field or longitudinal field inductor.Furthermore, the process chamber of rapid heating zone 12 is connected to the process chamber of heating / holding zone 4, as well as to the elements upstream of the rapid heating zone, in a gas-tight manner, with respect to the external environment of the vertical furnace. Thus, there are gas-tight connectors between the process chamber (muffle) of rapid heating zone 12 and the upstream / downstream elements. The process chamber of rapid heating zone 12 is structurally and inertly connected to the process chamber of heating / holding zone 4. Inlet zone 3 is also connected to rapid heating zone 12 in a gas-tight manner with respect to the environment of vertical furnace 1.

[0053] Furthermore, the rapid heating zone 12 can also be integrated into a higher-level safety system of the vertical furnace 1. The use of the inductor enables rapid heating of the metal strip 2 and a significant increase in throughput.

[0054] Furthermore, at least one dancer roller 14 mounted in a housing 13 can be arranged in the inlet zone 3 and / or in the outlet zone 4. According to Fig. 2 The housing 13 may have an inlet opening 15 and an outlet opening 16 for the metal strip 2. A protective gas atmosphere, in particular a hydrogen and / or nitrogen atmosphere, may prevail in the interior of the housing 13.

[0055] According to Fig.1 At least one sealing device 24 or 8, respectively, is arranged at an end section of the upward strand 17 and / or the downward strand 18 facing away from the deflection device 6 for sealing against the ambient atmosphere. The inlet zone 3 is thus connected to the upward strand 17 and the outlet zone 4 to the downward strand 18 of the vertical furnace 1 in a gas-tight manner with respect to the surroundings of the vertical furnace 1. According to Fig. 3The sealing device 24 can have an inlet opening 25 and an outlet opening 26 for the metal strip 2. The sealing device 24 is preferably designed as an oil seal. The sealing device 24 can be connected directly to the housing 13.

[0056] As from Fig. 1As can be further seen, the vertical furnace 1 can have a first tubular muffle 17a and a second tubular muffle 17b within which the metal strip 2 is guided. The interior of the muffle 17a represents the process space of the heating / holding zone 4, and the muffle 17b represents the process space of the cooling zone 5. The coupling device 20 is arranged between the first muffle 17a and the second muffle 17b and connects the two muffles 17a and 17b at their ends. The heating / holding zone 4 is arranged along the first muffle 17a, the first cooling zone 5 along the second muffle 17b, while the second cooling zone 9 and the third cooling zone 11 are arranged in the downward strand 18.A protective gas atmosphere, in particular a hydrogen atmosphere, with a high H2 content (30% - 100% H2) and low dew points (-20°C to -70°C) can prevail in the first muffle 17a and the second muffle 17b, as well as in the deflection device 6, the second cooling zone 9, and the third cooling zone 11, to prevent oxidation. In this context, the vertical furnace 1 can comprise, for example, a gas supply unit, in particular a hydrogen supply, connected to the interior of the first muffle 17a and / or the interior of the second muffle 17b. Furthermore, a device for determining particles in the atmosphere within the muffles 17a, 17b, the deflection device 6, the second cooling zone 9, and the third cooling zone 11 can be provided.

[0057] As from Fig. 3As can be seen, a thermal insulation 19 can also be provided to insulate the first muffle 17a and / or second muffle 17b. The rapid heating zone 12 can be arranged in front of the first muffle 17a and connected to it in a gas-tight manner with respect to the external atmosphere.

[0058] The heating / holding zone 4 can be arranged along the muffle 17a, and the first cooling zone 5 can be arranged along the muffle 17b. The two muffles 17a and 17b can be connected to each other via a coupling device 20.

[0059] In the heating / holding zone 4, one or more electrical heating elements 21 can be arranged on an outer surface of the first muffle 17a, in particular extending in the circumferential direction along the muffle 17a, as shown in Fig. 3 The heating element 21 can be arranged between the thermal insulation 19 and the muffle 17a.

[0060] Furthermore, the heating element 21 can be surrounded by a refractory layer 22, for example, a layer of vacuum-formed bricks. The heating element 21 is arranged between the at least one first muffle 17a and the refractory layer 22. Furthermore, at least one layer 23 of a fibrous material, for example, a nonwoven, a knitted fabric, a woven fabric, a braid, or felt, can be arranged on the refractory layer 22. The refractory layer 22 is arranged between the at least one heating element 21 and the at least one layer 23 of fibrous material.

[0061] Out of Fig. 4 and 5the detailed structure of the cooling zone 5 of the ascending strand is shown. The cooling zone 5 is designed as a slow radiation cooling zone in which the metal strip is cooled only by emitting thermal radiation against a cooled wall 29 of the muffle 17b. Inside the muffle 17b, i.e. in the process space of the cooling zone 5, there is a protective gas atmosphere with a high H 2 content of 30% - 100% H 2 and low dew points of -20°C to -70°C. The cooling zone 5 has a process space designed as a muffle 17b, which is gas-tight with respect to the external atmosphere of the vertical furnace 1. The muffle 17b can, however, be connected to the muffle 17a and the deflection device 10 and the downward strand 18 in terms of protective gas, so that at least a small exchange of protective gas between these areas is possible.

[0062] A cooling / heating chamber 28 through which a cooling fluid 27 flows is arranged around the process chamber of the first cooling zone 5. The cooling / heating chamber 28 is defined by the wall 29 of the muffle 17b and an externally insulated housing 37. A surface of the wall 29 of the muffle 17b surrounding the process chamber, facing the cooling / heating chamber 28, is exposed to the cooling fluid 27. The cooling fluid 27, which is preferably a gas or gas mixture, for example, air, N2, or other gases or gas mixtures, thus cools the muffle 17b from the outside. The hot metal strip 2 releases its energy in the form of radiation via the cooled muffle wall.

[0063] The cooling fluid 27 can be passed through a heat exchanger 30 to recover heat from the cooling fluid 27 flowing out of the cooling / heating chamber 28 and to cool the cooling fluid 27. Alternatively or in addition to the use of a heat exchanger, however, fresh cooling fluid 27, for example in the form of fresh air, can also be fed into the cooling fluid flow via a supply line and blown into the cooling / heating chamber 28 to cool the muffle wall.

[0064] Furthermore, a discharge line may be provided for expelling cooling fluid 27 flowing out of the cooling / heating chamber. A turbomachine 32, in particular a fan, is provided to generate a flow in the cooling fluid 27.

[0065] Furthermore, a heating device 31 for heating the cooling fluid 27 can be provided. The heating device 31 allows the temperature of the cooling fluid 27 to be varied according to the given process requirements, thus allowing targeted intervention in the cooling behavior of the metal strip 2 in the cooling zone 5. The cooling and heating system can be divided into one or more control zones along the length of the muffle 17b. The cooling-heating system of the cooling zone 5 also allows the temperature of the metal strip to be maintained within this range.

[0066] Furthermore, a temperature measuring device 33 for measuring the temperature in the cooling / heating chamber 28, as well as a temperature measuring device 34 for measuring the temperature of the cooling fluid 27 flowing out of the cooling / heating chamber 28, and a temperature measuring device 35 for measuring the cooling fluid 27 flowing into the cooling / heating chamber 28 can be provided. The vertical furnace 1 or a furnace control system, for example a suitably programmed processor, can be configured to change the temperature of the cooling medium 27 flowing into the cooling / heating chamber 28 as a function of a temperature measured in the cooling / heating chamber 28 and / or the flow rate of the cooling medium 27.

[0067] Furthermore, in addition to temperature control, pressure control of the cooling system can also be implemented. For this purpose, a pressure measuring device 36 for measuring pressure can also be arranged in the cooling / heating chamber 28.

[0068] The special design of cooling zone 5 enables slow and even cooling of the metal strip 2 in a purest protective gas atmosphere (30% to 100% H2, dew point -20°C to -70°C).

[0069] For the sake of clarity, it should finally be pointed out that, in order to better understand the structure, some elements have been shown out of scale and / or enlarged and / or reduced in size. Reference symbol list

[0070] 1 Vertical furnace 29 wall 2 metal band 30 heat exchanger 3 Admission zone 31 Heating device 4 Heating / holding zone 32 Turbomachine 5 Cooling zone 33 Temperature measuring device 6 deflection device 34 Temperature measuring device 7 Roller arrangement 35 Temperature measuring device 8 Outlet zone 36 Pressure measuring device 9 Cooling zone 37 Insulated housing 10 Housing 11 Cooling zone 12 Rapid heating zone 13 Housing 14 Dancer role 15 Inlet opening 16 Outlet opening 17 Upstream strand 17a first muffle 17b second muffle 18 Downward strand 19 insulation 20 coupling 21 heating element 22 layer 23 material 24 Sealing device 25 Inlet opening 26 Outlet opening 27 Cooling fluid 28 Cooling / heating room

Claims

1. A vertical furnace (1) for the continuous heat treatment of a metal strip (2), in particular an electrical steel strip, wherein the vertical furnace (1), as seen in a conveying direction of the metal strip (2), comprises - an inlet zone (3) for the metal strip (2); - a heating / holding zone (4) with an annealing chamber for heating and holding the metal strip (2) at a certain temperature; - at least one first cooling zone (5) for cooling the metal strip (2); - at least one deflection device (6) arranged downstream of the first cooling zone (5) for deflecting the metal strip (2) in the direction of an outlet zone (8) for the metal strip (2), wherein at least one second cooling zone (9) is arranged downstream of the deflection device (6) with respect to the conveying direction, characterized in that the first cooling zone (5) is configured as a radiation cooling zone for the metal strip, wherein a cooling / heating chamber (28) through which a cooling fluid (27) flows is arranged around the process chamber of the first cooling zone (5), wherein a lateral surface, which faces the cooling / heating chamber (28), of a wall (29) surrounding the process chamber is acted upon by the cooling fluid (27).

2. The vertical furnace according to claim 1, characterized in that it has a protective gas atmosphere with a high H2 content of 30% - 100% H2 and low dew points of -20°C to -70°C, at least in the heating / holding zone (4), in the first cooling zone (5), in the deflection device (6) and in the second cooling zone (9) for heat treatment of the metal strip, in order to avoid oxidation.

3. The vertical furnace according to claim 1 or 2, characterized in that the heating / holding zone (4) and the first cooling zone (5) each comprise at least one process chamber with an inlet opening and an outlet opening for the metal strip, in particular a metallically encapsulated process chamber, for example at least one process chamber surrounded by a muffle (17a, 17b).

4. The vertical furnace according to claim 3, characterized in that the process chamber of the heating / holding zone (4) is connected to the process chamber of the first cooling zone (5) in a gas-tight manner.

5. The vertical furnace according to claim 1, characterized in that the cooling fluid (27) is a gas or a gas mixture, in particular air.

6. The vertical furnace according to one of claims 1 to 5, characterized in that the cooling fluid (27) is passed through a heat exchanger (30).

7. The vertical furnace according to one of claims 1 to 6, characterized in that it comprises at least one supply line for supplying fresh cooling fluid, in particular fresh air.

8. The vertical furnace according to claim 7, characterized in that it comprises at least one discharge line for discharging cooling fluid flowing out of the cooling / heating chamber from the vertical furnace (1).

9. The vertical furnace according to one of claims 1 to 8, characterized in that it comprises at least one flow machine (32), in particular a blower, for generating a flow in the cooling fluid (27).

10. The vertical furnace according to one of claims 1 to 9, characterized in that at least one heating device (31) for heating the cooling fluid (27) is provided.

11. The vertical furnace according to one of claims 1 to 10, characterized in that it comprises at least one temperature measuring device (33) for measuring the temperature in the cooling / heating chamber (28).

12. The vertical furnace according to one of claims 1 to 11, characterized in that it comprises at least one temperature measuring device (34) for measuring the temperature of the cooling fluid (27) flowing out of the cooling / heating chamber (28) and at least one temperature measuring device (35) for measuring the cooling fluid (27) flowing into the cooling / heating chamber (28).

13. The vertical furnace according to one of claims 11 or 12, characterized in that it is configured to change the temperature of the cooling medium (27) flowing into the cooling / heating chamber (28) as a function of at least one temperature measured in the cooling / heating chamber (28), and / or the flow rate of the cooling medium (27).

14. The vertical furnace according to one of claims 1 to 13, characterized in that at least one pressure measuring device (36) for measuring a pressure in the cooling / heating chamber (28) is arranged in the cooling / heating chamber (28).

15. The vertical furnace according to one of claims 1 to 14, characterized in that the at least one second cooling zone (9) comprises at least one spray and / or nozzle cooling and / or jet cooling for applying cooling fluid to a surface of the metal strip.

16. The vertical furnace according to claim 15, characterized in that the cooling fluid of the at least one second cooling zone (9) comprises or is an inert gas, in particular H2.

17. The vertical furnace according to one of claims 1 to 16, characterized in that the first cooling zone (5) and the second cooling zone (9) are connected to each other in a gas-tight manner with respect to an environment of the vertical furnace at their ends facing the deflection device (6) via a housing (10) of the deflection device (6).

18. The vertical furnace according to one of claims 1 to 17, characterized in that the deflection device (6) is thermally insulated.

19. The vertical furnace according to one of claims 1 to 18, characterized in that the deflection device (6) comprises at least one heating means.

20. The vertical furnace according to claim 19, characterized in that the deflection device (6) comprises a temperature measuring unit and a temperature control unit, wherein the temperature control unit is configured to adjust a temperature level of the deflection device to a temperature level of the metal strip (2) by means of the at least one heating means.

21. The vertical furnace according to one of claims 1 to 20, characterized in that at least one roller arrangement (7) of the deflection device (6) is configured for center control of the metal strip.

22. The vertical furnace according to one of claims 1 to 21, characterized in that it comprises an additional rapid heating zone (12) for the metal strip with at least one heating device upstream of the heating / holding zone (4) in the conveying direction of the metal strip (2).

23. The vertical furnace according to claim 22, characterized in that the at least one heating device of the rapid heating zone (12) is configured as an induction heater, wherein the rapid heating zone (12) comprises a process chamber with a wall (29) of a non-metallic material as well as an inlet opening and an outlet opening for the metal strip (2), wherein the process chamber of the rapid heating zone (12) has an inert gas atmosphere with a high H2 content of 30% - 100% H2 and low dew points of -20°C to -70°C, and the induction heater is arranged outside the process chamber.

24. The vertical furnace according to claim 23, characterized in that the process chamber of the rapid heating zone (12) is connected to the process chamber of the heating / holding zone (4) in a gas-tight manner with respect to the external environment of the vertical furnace (1).

25. The vertical furnace according to one of claims 1 to 24, characterized in that a third cooling zone (11) is provided, which third cooling zone (11) is arranged downstream of the second cooling zone with respect to the conveying direction of the metal strip, wherein the third cooling zone (11) has an inert gas atmosphere with a high H2 content (30% - 100% H2) and low dew points (-20°C to -70°C).

26. The vertical furnace according to one of claims 1 to 25, characterized in that in each case at least one dancer roller (14) mounted in a housing (13) is arranged in the inlet zone (3) and / or in the outlet zone (4), wherein the housing (13) in each case comprises an inlet opening (15) and an outlet opening (16) for the metal strip (2) and an inert gas atmosphere, in particular a hydrogen and / or nitrogen atmosphere, is present in the interior of the housing (13).

27. The vertical furnace to one of claims 22 to 26, characterized in that the inlet zone (3) is connected to the rapid heating zone (12) in a gas-tight manner with respect to an environment of the vertical furnace (1).

28. The vertical furnace according to one of claims 1 to 27, characterized in that the outlet zone (4) is connected to a downward strand of the vertical furnace (1), which comprises at least the second cooling zone (9), in a gas-tight manner with respect to an environment of the vertical furnace (1).