Apparatus and method for producing and further processing of slabs

Abstract

An apparatus for producing and further processing slabs of a metal, preferably steel, comprises: a continuous casting apparatus, which is designed to produce at least one cast strand and to transport it in a transport direction; a cutting device, which is arranged behind the continuous casting apparatus, as seen in the transport direction, and is designed to cut the cast strand into slabs; at least a first route and a second route, which implement, at least in some portions, different process lines for the further processing of the slabs; and a process control system, which is designed to make a route decision on a slab-specific basis as a function of at least one measured or calculated process parameter, which route decision assigns one of the plurality of routes to the respective slab, and to initiate the further processing of the corresponding slab along the assigned route.

Claims

1-21. (Canceled)

22. An apparatus (100) for producing and further processing of slabs (3) of a metal, comprising: a continuous casting apparatus (1), which is designed to produce a cast strand (S) and to transport it in a transport direction (T); a cutting device (4), which is arranged behind the continuous casting apparatus (1), as seen in the transport direction (T), and is designed to cut the cast strand (S) into slabs (3); a first route (R1) and a second route (R2) implementing, at least in some portions, different process lines for the further processing of the slabs (3); and a process control system (8), which is designed to make a route decision individually for each slab as a function of at least one measured or calculated process parameter, which route decision assigns the respective slab (3) to the first route (R1) or to the second route (R2), and to initiate further processing of the corresponding slab (3) along the assigned route (R1, R2).

23. The apparatus (100) according to claim 22, further comprising a walking-beam furnace (2) which is arranged behind the cutting device (4), as seen in the transport direction (T), and which is designed to heat the slabs (3) to a forming temperature in a range from 1,000° C. to 1,300° C. for forming the slabs (3) in a rolling mill (12).

24. The apparatus (100) according to claim 23, wherein the first route (R1) is designed to insert the corresponding slab (3) into the furnace (2) substantially directly after cutting by the cutting device (4) with a surface temperature of 850° C. or more.

25. The apparatus (100) according to claim 24, wherein no deburring device is provided on the first route (R1) between the cutting device (4) and the furnace (2).

26. The apparatus (100) according to claim 23, wherein the second route (R2) is designed to feed the corresponding slabs (3) to a slab storage facility (11) for intermediate storage after cutting by the cutting device (4).

27. The apparatus (100) according to claim 26, wherein the second route (R2) is designed to discharge the corresponding slabs (3) in front of the furnace (2) or to route them past the furnace (2).

28. The apparatus (100) according to claim 27, further comprising a heating device (18), which is designed to preheat slabs (3) that have undergone cooling in the slab storage facility (11) to a temperature of 850° C. or more.

29. The apparatus (100) according to claim 23, further comprising a rolling mill (12) with one or more rolling stands (13), which is arranged behind the furnace (2) when viewed in the transport direction (T).

30. The apparatus (100) according to claim 23, further comprising a forming unit which is arranged behind the furnace (2) when viewed in the transport direction (T), wherein the forming unit comprises one or more descaling devices (16) and/or one or more heating apparatuses (6) and/or one or more inspection systems (21) and/or a welding device (22) for welding together successive slabs (3) or intermediate strips.

31. The apparatus (100) according to claim 22, wherein the first route (R1) or to the second route (R2) is designed to discharge the corresponding slabs (3) after cutting by the cutting device (4).

32. The apparatus (100) according to claim 22, wherein the process control system (8) is designed to make the route decision for the slab (3) taking into account one or more of the following measured or calculated process parameters: surface temperature of the slab (3), metallurgical properties of the slab (3), Si content, steel grade, quality of the slab (3), surface finish, and planned end use.

33. The apparatus (100) according to claim 22, wherein the cutting device (4) comprises an inspection system (7) or an inspection system (7) is arranged substantially directly behind the cutting device (4) and is communicatively coupled to and designed with the process control system (8), in order to detect one or more physical quantities of the slabs (3) and transmit them to the process control system (8), wherein the process control system (8) is designed to use data received from the inspection system (7) for the route decision.

34. The apparatus (100) according to claim 22, wherein one or more heating apparatuses (6) are arranged upstream of the cutting device (4) or of a decoupler (5) and/or downstream of the cutting device (4), wherein the heating apparatuses (6) are implemented inductively, with gas burners or electrically.

35. The apparatus (100) according to claim 22, wherein the apparatus is designed for producing and further processing of medium slabs (3) with a slab thickness in a range of 140 to 200 mm.

36. The apparatus (100) according to claim 22, wherein the continuous casting apparatus (1) comprises an ingot mold (1a) that is designed to receive molten metal and discharge the cast strand (S) downwardly, wherein the ingot mold (1c) comprises two facing plane-parallel plates that define a thickness of the cast strand in a range of 140 to 200 mm.

37. The apparatus (100) according to claim 22, wherein the cutting device (4) comprises pendulum shears.

38. A method for producing and further processing of slabs (3) of a metal, preferably steel, comprising: producing and transporting a casting strand (S) along a transport direction (T) by a continuous casting apparatus (1); cutting the cast strand (S) into slabs (3) by a cutting device (4), which is arranged behind the continuous casting apparatus (1) when viewed in the transport direction (T); carrying out an individual route decision as a function of at least one measured or calculated process parameter, which assigns one of several routes (R1, R2) to the respective slab (3); and further processing the corresponding slab (3) along the assigned route (R1, R2).

39. The method according to claim 38, wherein slabs (3), which are further processed along a first route (R1), are introduced after cutting into a furnace (2), which is arranged behind the cutting device (4) as seen in the transport direction (T), in order to heat the corresponding slabs (3) to a forming temperature in a range of 1,000° C. to 1,300° C. for forming the slabs (3) in a rolling mill (12).

40. The method according to claim 39, wherein the slabs (3) of the first route are inserted into the furnace (2) substantially directly after cutting at a temperature of 850° C. or more.

41. The method according to claim 39, wherein slabs (3) of crack-critical grades of the first route are inserted into the furnace (2) substantially directly after cutting at a surface temperature of less than 600° C. after undergoing quenching or intensive cooling.

42. The method according to claim 39, wherein the slabs (3), which are further processed along a second route (R2), are supplied to a slab storage facility (11) for intermediate storage after cutting by the cutting device (4).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0065] FIG. 1 schematically shows an apparatus for the production, further processing and forming of slabs.

DETAILED DESCRIPTION

[0066] Preferred exemplary embodiments are described below with reference to the figure. In this context, identical, similar or similarly acting elements are provided with identical reference signs, and a repetitive description of such elements is partially omitted in order to avoid redundancy.

[0067] FIG. 1 schematically shows an apparatus 100 for the production and further processing of slabs 3. The slabs 3 are preferably medium slabs, that is, slabs with a thickness in the range of approximately 110 to 200 mm, preferably 140 to 200 mm.

[0068] The apparatus 100 comprises one or more continuous casting apparatuses 1, which in the present exemplary embodiment is implemented as a vertical bending plant. However, the continuous casting apparatus 1 can be implemented in other manners as long as it provides a casting strand that can be subsequently cut into slabs and further processed.

[0069] The molten metal to be cast is fed to an ingot mold 1a of the continuous casting apparatus 1, for example from a casting ladle. The ingot mold 1a brings the molten metal into the desired slab shape as it solidifies gradually from the outside inward through the cooled ingot mold walls. The ingot mold 1a is preferably an ingot mold made of copper plates (or plates of a copper alloy, which may be coated), in the case of medium slabs with plane-parallel plates on the broad sides and narrow sides, which are adapted for a comparatively high casting thickness of, for example, 140 mm or more. If required by the casting thickness or casting radius, the copper plates can have a funnel-shaped contour and/or be curved in a transport direction T corresponding to the casting radius of a strand guide 1b.

[0070] The casting strand S, which has not yet solidified, emerges downward from the ingot mold 1a, then continues to be guided downward in the transport direction T along the strand guide 1b, and then is deflected into the horizontal in a bending region while it gradually cools down. It should be noted that the transport direction T does not denote a constant direction vector, but may depend on the strand or slab position, as the case may be, along the apparatus 100.

[0071] The strand guide 1b comprises rollers 1c that transport the cast strand S and can be adjusted for thickness reduction in accordance with LCR or DSR in such a manner that the transport gap in which the cast strand is transported along the transport direction T gradually narrows. The strand guide 1b can be constructed in a segmental manner, for example by two or more curved segments similar in construction, which curved segments can form a bending region of the strand guide 1b. During transport, the cast strand S is cooled actively or passively, for example by splash water, causing it to solidify gradually from the outside to the inside.

[0072] The bending region of the continuous casting apparatus 1 is followed by a straightening region, in which the cast strand S is brought into horizontal alignment. Rollers 1c are also provided here for guiding and transporting the casting strand S. One or more of the rollers 1c are drive rollers and drive the casting strand S forward in the transport direction T; other rollers 1c serve to guide and align the casting strand S. In this respect, the rollers 1c form means for driving and bending the casting strand S.

[0073] The apparatus 100 further comprises a cutting device 4, which is arranged in or behind the continuous casting apparatus 1 in the transport direction T, in particular behind the straightening region of the continuous casting apparatus 1. The cutting device 4 is used to cut or divide, as the case may be, the cast strand S into slabs 3. The cut is made along the slab thickness. “Slab thickness” is the dimension of the slab that is perpendicular to the extension of length and perpendicular to the width (in FIG. 1, perpendicular to the paper plane) of the slab. Thereby, the cutting device 4 is designed to cut the casting strand S during conveying, that is, during the movement of the casting strand S along the conveying direction T. Preferably, the cutting device 4 is a shear, in particular a pendulum shear. In this case, the shear is designed to track the transport movement of the casting strand S during the cutting operation, and one or more cutting blades cut the strand in a movement vertical to the casting strand S only.

[0074] Upstream or downstream of the cutting device 4, a decoupler 5 can be provided, for example in the form of a cold strand rocker, which is designed to be able to decouple the casting strand S from the process line if necessary, for example when starting up the plant.

[0075] Behind the cutting device 4, a preferably automated decision is made as to which route the slab 3 will take in the further course, wherein at least two routes R1 and R2 are implemented. Thus, the process line has a branching after the cutting device 4. It should be noted that the arrows R1 and R2 in FIG. 1 only schematically indicate the different routes and do not necessarily reflect the actual transport path of the slabs 3.

[0076] In the present exemplary embodiment, the first route R1, also referred to herein as the “immediate processing path,” takes the slab 3 as quickly as possible after it has been cut by the cutting device 4 into a furnace 2, which brings the slab 3 to forming temperature. The second route R2, also referred to herein as the “storage path,” transports the slab 3 to a slab storage facility 11. However, the routes R1 and R2 shown in FIG. 1 are only exemplary.

[0077] Process control, including possible decision criteria for individual processing of the slab 3, is detailed below. First, the further structure of the apparatus 100 in accordance with the exemplary embodiment of FIG. 1 shall be explained:

[0078] In the case of the immediate processing path, the cut slabs 3 are fed to a furnace 2 via a roller table 19. The furnace 2 is arranged behind the cutting device 4, when viewed in the transport direction T, and is designed to heat the slabs 3 to a forming temperature, preferably in the range of 1,000° C. to 1,300° C.

[0079] The furnace 2 is located as close as possible behind the cutting device 4, in order to minimize the cooling of the slabs 3, by which the immediate processing path enables a particularly energy-efficient further processing of the slabs 3.

[0080] The furnace 2 is preferably a walking beam furnace, in which the slabs 3 are moved in a walking direction during heating. For this purpose, the walking beam furnace has fixed beams and walking beams, a walking drive and heating means, which are not described in detail herein. However, the furnace 2 can also be constructed in other manners, such as a horizontal continuous furnace, a tunnel furnace, a furnace with a chain and the like.

[0081] In the present process line, a forming unit, preferably a rolling mill 12, is connected to furnace 2 when viewed in the transport direction T.

[0082] The rolling mill 12 comprises one or more rolling stands 13 and can be operated in reversing or tandem mode. However, the structure of the forming unit is not limited to the example shown in FIG. 1. For example, a combination of optionally reversing roughing stands and a finishing line with intermediate heating and/or cooling apparatuses 6 can be implemented. The forming unit or rolling mill 12, as the case may be, can have one or more descaling devices 16 that are arranged in front of or behind one or more rolling stands 13, depending on the configuration. The forming unit can be followed by a cooling section 14 and/or a discharge device 15, for example one or more coiling units.

[0083] Furthermore, the forming unit can be equipped with one or more inspection systems 21 for automatic inspection of the semi-finished product, for example with regard to surface condition, microstructure and the like.

[0084] Preferably, the forming unit comprises a welding device 22 for welding together individual workpieces, such as slabs 3 or intermediate strips, whereby forming can be performed on a continuous workpiece. For example, in the case of a rolling mill 12, the welding device 22 can be installed before or in front of the last stand group. This allows individual, successive slabs 3 or intermediate strips, as the case may be, to be rolled endlessly. Strip rolled in this manner can, if necessary, be separated again by a high-speed shear 23 in front of a coiling device.

[0085] The structure of the apparatus 100 set forth herein allows for a shortening of the cooling section between the one or more continuous casting apparatuses 1 and the furnace 2 along the immediate processing path. Conventional apparatuses such as flame cutting device(s), deburring device(s), marking machine(s), a slab storage facility and the like in front of furnace 2 can be omitted along this route, and in the simplest case these are replaced by the cutting device 4. Thus, the path of the slabs 3 produced by the cutting device 4 via the roller table 19 to the furnace 2 is considerably shortened. In the case of a slab length of, for example, 16 m, the cooling section can be shortened to a length of approximately 21 m.

[0086] In this manner, the temperature required for hot forming the slabs 3 is achieved with less heat loss. Furthermore, the mechanical removal of the burr and the equipment required for this are no longer necessary. Any slab storage facility 11 with marking machine(s) can be omitted on this route or at least reduced in size overall in the plant, since essential reasons for its use become obsolete.

[0087] The slabs 3 are inserted into the furnace 2 at a comparatively high temperature of 600° C. or more, preferably 850° C. or more, which allows the furnace 2 and thus the plant as a whole to be designed to be more compact and to conserve resources, in particular to save energy. This leads to resource-saving and cost-effective production of metallurgical semi-finished products, in particular peritectically transforming or crack-critical steel grades, microalloyed steel grades, steel grades for pipeline production and steel grades with high surface quality requirements.

[0088] To support the technical effects specified above, one or more heating apparatuses 6, preferably inductive, using gas burners or operating electrically, can be installed at different positions in the process line. Preferably, one or more heating apparatuses 6 are located substantially directly upstream of the cutting device 4 or decoupler 5, if present, and/or downstream of the cutting device 4. On the one hand, heating apparatuses 6 of this type can help to shorten the cooling section, and, on the other hand, they simplify slab storage logistics.

[0089] In the process region between the continuous casting apparatus 1 and the furnace 2, one or more inspection systems 7 can be installed to check the slab quality, for example the surfaces of the slabs 3. The inspection systems 7 are connected to process control systems 8 in the network and can make decisions on further processing and process route, or support them with information.

[0090] In the present exemplary embodiment, the second route, the storage path, takes the slabs 3 behind the cutting device 4 to a slab storage facility 11, where they can be temporarily stored. The slab storage facility 11 can be located behind the furnace 2, such that the slabs 3 are directed past the furnace 2 via the roller table 19, allowing the subsequent slabs 3 from the continuous casting apparatus 1 to be transported unimpeded into the furnace 2, provided that an appropriate route decision is made. Alternatively, the slabs 3 can be transported in front of the furnace 2 via a branching roller table to the slab storage facility 11.

[0091] Conversely, slabs 3 can be fed into the process line from other sources, such as from the slab storage facility 11 itself or via the slab storage facility 11 from another location, via a feed-in roller table 17. Feeding into the process line leading to furnace 2 can be done in different manners. Thus, it is possible to control the supply of slabs 3 from other sources such that they are fed into gaps between slabs 3 that are in the immediate processing path. Alternatively or additionally, parallel conveying is possible, with which the slabs 3 are transported on a plurality of parallel roller tables before being inserted into the furnace 2. Parallel transport of slabs 3 through the furnace 2 can also be implemented.

[0092] If required, one or more heating devices 18 can be installed, such that slabs 3 that have undergone cooling in the slab storage facility 11 are preheated by the heating device 18 to a temperature that is suitable for subsequent introduction into the furnace 2, that is, in particular to a temperature above 600° C., preferably 850° C.

[0093] Furthermore, slabs 3, which are to be cooled and temporarily stored in the slab storage facility 11, for example, can be marked by means of a marking machine 20, which is preferably arranged downstream of the furnace 2, such that they can be identified by the operating personnel of the apparatus 100 and/or by a suitable sensor system.

[0094] By feeding the slabs 3 into the common process line leading into the furnace 2 after passing through different routes, the furnace 2 and the forming unit 12 can be operated independently of the specific path that was previously taken by the respective slab 3. The forming unit 12 can operate continuously without “knowing” where the slabs 3 are coming from. A control engineering coupling between the different plant components is not necessary in this respect, or can be kept simple, such that the retrofitting of existing plants is possible without a complete new design.

[0095] Furthermore, by suitable planning or control of the process, as the case may be, a continuous casting and rolling operation or at least a continuous rolling operation can be maintained at any time in order to utilize the apparatus 100 in the best possible and energy-saving manner in terms of maximum production. This also includes the fact that, in the event of a planned or unplanned stoppage of the continuous casting apparatus 1, slabs 3 can be fed to the furnace 2 from the slab storage facility 11 or from an external source cold or, if necessary, with preheating in a further heating device included in the apparatus 100 and subsequently rolled, thus ensuring the best possible utilization of the forming unit 12 even in the event of a casting stoppage.

[0096] The apparatus 100 has one or more process control systems 8 that are responsible for process control. The monitoring and planning of the overall process can be taken over by a process planning system 9, such that so-called “Level 1,” “Level 2” and “Level 3” systems can be implemented in this manner. The process control systems 8 are communicatively connected to sensors, actuators, storage media and the like, as shown by corresponding lines in FIG. 1. Communication can be wireless or wired.

[0097] The process control systems 8 are networked with each other and/or with the process planning system 9 (“Level 3”) by means of a network 10, for example, for controlling the molten steel production, continuous casting apparatus 1, slab logistics, upstream heating device 18, furnace 2, forming unit (such as rolling mill 12 and cooling section) and/or the conveying devices for transporting the slabs 3, plates and/or strips. The process planning and process control can optionally be provided with automation across process stages, for example to reduce energy consumption while at the same time optimizing process control in terms of technology and energy, and/or to minimize the throughput time of the products and/or to improve product quality.

[0098] Detected data and/or data obtained by processing/calculation from the process or from the products can be stored, for example on data carriers, in databases or network storage (cloud), and used by systems 8, 9 for process optimization and performance enhancement.

[0099] In accordance with a preferred exemplary embodiment, one of the process control systems 8 is an electronic warehouse management system 8′, which is designed to automatically record measured or calculated process parameters of the slabs 3 of the slab storage facility 11, for example their positions along with process parameters and quality characteristics. The recorded measured or calculated process parameters can be processed for various purposes, for example to automatically identify a suitable slab 3 according to the specifications of a process planning system 9 and to feed it to the process line at a suitable point.

[0100] At least one process control system 8 is designed to decide for each slab 3 which route—the immediate processing path or the storage path in the present exemplary embodiment—it will take. The decision is preferably made directly behind the cutting device 4, wherein the immediate processing path can be assumed as the rule.

[0101] Measured or calculated process parameters on which the decision can be based include, for example: Temperature of the slab and/or cooling curve during primary and secondary cooling in the continuous casting apparatus 1 and/or steel grade and/or quality requirement and/or planned end use.

[0102] Suitable inspection systems 7, such as temperature sensors, cameras, or other sensors, can be installed at one or more locations along the process path in order to record the desired process variables. Such values can also be provided online by suitable, preferably computer-based process models. In the exemplary embodiment of FIG. 1, an inspection system 7 is installed substantially directly behind the cutting device 4. Provided that the cutting device 4 has its own inspection system, for example to detect defects such as surface cracks or other defects on the slab 3, such information can of course be used for the route decision.

[0103] For the route decision, the process planning system 9 or the corresponding process control system 8, as the case may be, can take customer requests into account. Thus, a slab 3 meeting special quality requirements can be discharged to the slab storage facility 11 or for direct purchase by the customer.

[0104] Thereby, the planned end application can play a special role, for example with regard to surface quality or degrees of forming for the deep drawing of sheets to be produced from the corresponding slab 3. For example, particularly high demands are usually placed on surface quality for automotive outer skin. Similarly, high demands are placed on Si alloyed grades for electrical sheet production (for example, E strip with Si contents greater than 3% and Al contents greater than 0.3%).

[0105] The process outlined here with route branching enables the separate processing of slabs of different grades and quality characteristics, in particular surface qualities, in an automated manner at an early stage.

[0106] To the extent applicable, any of the individual features shown in the exemplary embodiments may be combined and/or interchanged.

LIST OF REFERENCE SIGNS

[0107] 100 Apparatus for the production and further processing of slabs [0108] 1 Continuous casting apparatus [0109] 1a Ingot mold [0110] 1b Strand guide [0111] 1c Roller [0112] 2 Furnace [0113] 3 Medium slab [0114] 4 Cutting device [0115] 5 Decoupler [0116] 6 Heating apparatus [0117] 7 Inspection system [0118] 8 Process control system [0119] 8′ Warehouse management system [0120] 9 Process planning system [0121] 10 Network [0122] 11 Slab storage facility [0123] 12 Rolling mill [0124] 13 Rolling stand [0125] 14 Cooling section [0126] 15 Discharge device [0127] 16 Descaling device [0128] 17 Feed-in roller table [0129] 18 Heating device [0130] 19 Roller table [0131] 20 Marking machine [0132] 21 Inspection system [0133] 22 Welding device [0134] 23 High-speed shear [0135] S Casting strand [0136] T Transport direction [0137] R1 First route [0138] R2 Second route