WO2005120746A2 - Continuous casting plant and method for optionally casting a large metal billet or a maximum of two narrower metal billets - Google Patents

Abstract

The invention relates to a continuous casting plant for optionally casting a large metal billet or a maximum of two narrower metal billets. Said continuous casting plant comprises at least one distribution vessel, a permanent mold that is supported on an oscillating mechanism, and a billet guide which is mounted downstream thereof. In order to be able to individually cast both a large billet and two metal billets that are narrower than said large one, the continuous casting plant encompasses a chamber (25) for optionally accommodating one (5) or two permanent molds (5a, 5b) while two oscillating mechanisms (7a, 7b) and two billet guides (8a, 8b) with associated drive units (41) for separately and synchronously operating the oscillating mechanism and the billet guide are provided.

Description

Stranααießanlaqe and method for the optional casting of a wide metal strand or a maximum of two, in contrast, narrower metal strands

The invention relates to a continuous casting installation and a method for the optional casting of a wide metal strand or a maximum of two metal strands that are narrower in comparison. The continuous casting installation comprises at least one distributor vessel, a mold supported on an oscillating device and a downstream strand guide.

The terms “wide metal strand” and “in contrast narrower metal strand” are to be understood here in such a way that the width of a wide metal strand to be cast is greater than the sum of the two narrower metal strands to be cast at the same time. For example, such a continuous caster can cast a wide metal strand with a width of 3000 mm or alternatively two metal strands each with a width of 1300 mm, whereby when casting two metal strands they can also have different widths.

Metal strand is preferably to be understood as a steel strand, but also other metal strands, e.g. based on aluminum or aluminum alloys are possible. A continuous caster is preferably a steel continuous caster.

In order to increase the possible uses of a continuous slab caster for casting wide steel strands, it has long been known from the prior art to design the mold in such a way that a wide steel strand but also several steel strands with a smaller width can be cast.

For this purpose, it is already known, for example from DE-B 2 003 787, to use at least one separating element for producing at least two spatially separated mold cavities in an existing mold with a slab cross section, a mold cavity being formed by two broad side walls and two adjustable narrow side walls. This separable element, which can be fixed between the broad side walls of the slab mold, bears shaping narrow side walls that are the same as that opposite narrow side walls of the slab mold in their inclination to the casting direction can be adjusted depending on the strand width. In such continuous casting plants, however, there is no possibility of individually addressing the production conditions of the individual parallel cast strands. If a fault occurs on one of several strands, it is not possible to change the casting conditions specifically for this strand, such as reducing or increasing the casting speed or changing the oscillation parameters for this strand. A major disadvantage of this known embodiment is therefore that in the event of a fault on one strand, the casting parameters must be changed for all the strands or, in special cases, the casting process must be stopped for all the strands. Another disadvantage of this embodiment is that when casting two strands it is not possible to arrange the pouring tube largely centrally with variable pouring widths because of the fixed distance between the two pouring tubes on the distributor vessel.

From DE-A 37 06 720, a continuous casting installation for the simultaneous casting of two metal strands is known, two molds which can be positioned independently of one another being supported in a common lifting table frame. Casters are assigned to the two molds and a strand guide for supporting and guiding the strands adjoins them in the casting direction. An oscillation device is assigned to the lifting table, so that both molds must perform a predetermined oscillation movement together and individual parameter settings for each metal strand to be cast are therefore excluded.

DE-A 27 02 894 discloses a multi-strand continuous casting installation for the simultaneous casting of at least two metal strands, in which the spacing between the adjacent casting strands is to be reduced by special structural measures in order to keep the longitudinal extent of the distributor vessel as small as possible. This is achieved by a special arrangement of the drive roller drives. On the one hand, drive shafts built into one another are proposed, which enable all drives to start from one side of the installation, on the other hand it is proposed to arrange the drives above the casting installation. In this document, reference is also made to a twin continuous caster with which slabs and blooms can be produced at the same time. At the same time, attention is drawn to the difficult operating conditions of such systems, the melt supply and the strand withdrawal having to take place simultaneously, in particular in the starting phase of the casting process. It is therefore an object of the present invention to avoid the disadvantages of the known prior art and to improve a continuous casting installation and a method for the optional casting of a wide metal strand or a maximum of two metal strands which are narrower in comparison therewith, specifically addressing the individual requirements of each strand to be cast or can be reacted without influencing the possibly further metal strand to be cast.

A further advantage of the present invention lies in the fact that when two narrower strands are cast in parallel when a fault occurs on one strand, the casting of this strand can possibly be interrupted and the casting process of the further strand can be continued undiminished.

This object is achieved on the basis of a continuous caster of the type described in the introduction in that the continuous caster has a space for receiving one or two molds and two oscillating devices and two strand guides with associated drive devices are arranged for separate and synchronous operation of the oscillating devices and the strand guides.

Each of the two functionally independently operable oscillating devices can also include several, but preferably two, oscillating devices, which are operated synchronously in each operating case, for stable support of each mold.

The space for receiving one or two molds is limited in the strand conveying direction by the at least two oscillating devices, on which either one or two molds are supported. In the event that two molds are arranged, one mold is assigned to an oscillating device and these can accordingly be operated independently of one another. In the event that only one mold is provided for casting a wide metal strand, this mold is supported on both oscillating devices and these are operated synchronously. For structural reasons alone, it is expedient if each mold for casting a narrower metal strand is supported on two oscillating devices, which are separated from one another by a space for the passage of the cast metal strand, but are always operated synchronously. In this sense, four molds are then assigned to one mold for casting a wide metal strand. Similarly, when casting two narrow slabs, the two strand guides, one of which is assigned to a metal strand to be cast, are operated independently of one another. When casting a wide metal strand, which requires both strand guides to support it, the strand guides are operated synchronously, which means that the metal strand cannot run sideways.

All molds used are preferably designed as adjusting molds and have narrow side adjustment devices for adjusting the casting width and devices for setting a casting cone which is dependent on the casting width on at least one of the narrow side walls.

To ensure synchronous operation of the two oscillating devices when casting a single wide metal strand, each of the two oscillating devices is assigned a drive device for generating an oscillating movement, and this drive device is connected to a synchronization device for setting synchronous conditions of the oscillating movement. When casting two narrower metal strands at the same time, or if only one of the two narrower metal strands is cast for any reason, the synchronization device is out of operation and optimum casting conditions are set for each strand to be cast.

Preferably, the synchronization device for setting synchronization conditions of the oscillation movement is formed by a central processing unit.

Each oscillating device comprises a hydraulic actuator, e.g. a controllable pressure medium cylinder, and a control block that controls the oscillation movement generated by the hydraulic actuator. The control block is connected to the computing unit via signal lines, from which default values are transmitted to the control block. Instead of a controllable pressure medium cylinder, the oscillating device can comprise, for example, an adjustable eccentric drive.

Each oscillating device comprises a support block for supporting a mold and on the support surface of each support block and the corresponding counter support surface on the mold are quick coupling devices for the media supply (coolant, electricity, pressure medium lines, signal lines, etc.) and at least one guide and Centering devices arranged. This ensures a quick and automated mold change.

A quick and safe mold change is achieved if at least one manipulation device for changing the molds, preferably a change carriage, is arranged on the casting platform. The mold change, possibly with simultaneous change of the first strand guide segment following the mold, can also be carried out with an indoor crane assigned to the casting platform.

The space for holding one or two molds is directly adjoined by two strand guides running parallel and at a narrow horizontal distance, through which the cast one metal strand or the two metal strands are supported and guided on opposite sides. These two strand guides comprise roller stands with a few driven and a plurality of non-driven rollers, the driven rollers being connected to drive devices and the drive devices of the rollers of both roller stands being connected to one

Synchronization device for setting synchronous conditions of the driven rollers are connected.

As is usual in modern continuous casting plants, the roller stand is divided into a plurality of successive segments and some of the roller pairs in the strand guide, mostly one per segment, are coupled to drives and enable the controlled removal of the metal strand at a specified take-off speed (casting speed).

The synchronization device for setting synchronization conditions of driven rollers in the strand guide is preferably formed by a central processing unit.

An advantageous embodiment of the roller stands is that the rollers or pairs of rollers of both roller stands that cooperate when a wide metal strand is cast are supported in a common support frame or in successive segment frames. In order nevertheless to be able to apply individual forces to the two strands when casting two separate strands, the relatively movable roller of a pair of rollers or the relatively movable rollers of a group of Pairs of rollers in each of the two roller stands attached to independent roller carriers, which are supported in the common support frame or segment frame.

Each drive device of a driven roller is connected to it via a cardan shaft or other drive shaft and is arranged laterally outside the two roller stands of the strand guide which run next to one another. If the space provided for this is not sufficient, for example by arranging one or more additional strand guides of a multi-strand casting system or another independent casting system, there is also the possibility of connecting the driven roller to the drive device via a planetary gear and an angular gear and the drive device in to be arranged in a raised position laterally above the two adjacent roller stands of the strand guide.

In the outlet area of the continuous casting installation, each strand guide on an flame cutting roller table following the strand guide is assigned an independent separating device for cross-cutting one of the two, narrower metal strands cast in parallel, and each of these separating devices carries at least one separating element. Flame cutters are usually used as separators for slab cross sections. This gives the two separators the possibility of dividing two metal strands cast simultaneously at different casting speeds independently of one another and, if appropriate, also on slabs or blooms of different lengths.

The two separating devices are preferably arranged one behind the other in the strand conveying direction, with each separating device bridging both parallel strand guides or the flame cutting roller tables arranged in this area, and thus each of the two separating devices is capable of cross-dividing one of the two parallel cast metal strands.

At least one of the two separating devices is equipped with two cooperating separating elements for cross-cutting a wide metal strand, one separating element being assigned to a flame cutting roller table. When cross-cutting a wide metal strand, the cut is made with a slight time offset from the edges of the metal strand to the inside, as is also the case with conventional continuous casting plants when cross-cutting wide metal strands. In this case, the second separating device is in a waiting position. According to an alternative embodiment, the two separating devices are arranged next to one another and travel during the separating cut in the strand transport direction on carriageways which are arranged at a distance above the flame cutting roller table. In order to synchronize the travel movement when jointly dividing a wide metal strand, the two separating devices are locked to one another by a preferably electro-hydraulically actuated, mechanical coupling. The two separation devices can also be equipped with separate travel drives, with these travel drives being assigned a synchronization device which is controlled by a central processing unit. Each separating device preferably comprises at least one separating element, preferably formed by a cutting torch, which is arranged on a displacement device and allows a transverse movement to the transport direction of the cast metal strand, the displacement area of at least one of these separating elements of the one separating device into the displacement area of one of the separating elements of the another separation device protrudes.

Runout roller tables are arranged downstream of the strand guides and the associated separating devices, to which a transverse conveyor device for changing the transport direction of the strand pieces to be derived transversely to the strand transport direction is assigned.

A distributor vessel for the molten metal is positioned between a ladle and the mold or molds. This distributor vessel has a plurality of outlet openings for molten metal which are arranged in a line and to which closure elements are assigned, and these closure elements are connected to the central processing unit via signal lines and can be activated depending on the casting format of the downstream mold or mold. The closure members are formed by slides or plugs, as are usually used in continuous casting plants.

For the start of the continuous caster according to the invention, two starting strands are used through the strand guide to the exit-side end region of the one mold or the two molds, which are equipped with separate starting strand heads when using two molds and with a common starting strand head when using one mold.

Compared to a conventional two-strand caster, a continuous caster of the type according to the invention has the following advantages: • when casting a metal strand with a slab width of up to 3500 mm, two metal strands with a width of up to 1600 mm can alternatively be cast at the same time, • the effort for foundations and steel construction is reduced considerably during plant construction, • there can be a compact distributor for everyone Operating variants are used, • the background construction, in particular for the strand guide (banana), is only required twice instead of 4 times, • the investment costs of the continuous casting installation are reduced by a total of about 20%.

Compared to a conventional "twin-casting plant", as is known, for example, from DE-B 20 03 787 already mentioned at the beginning, a continuous casting plant of the type according to the invention has the following advantages: • A separate, independent mode of operation is separated by separate molds Oscillating devices, separate drives and separate cutting devices only possible, • with two-strand casting mode, the casting of the metal strands can take place independently of one another, • a breakthrough guide is possible for each strand independently, • in the event of a breakthrough, pouring on with one (the further) strand is possible, • The pouring tube can be changed independently of the second strand.

Furthermore, the invention comprises a method for the optional casting of a wide metal strand or two, in contrast, narrower metal strands in a continuous casting installation, an at least partially solidified metal strand being formed in a mold and the at least partially solidified metal strand being supported and guided in a subsequent strand guide. The object on which the invention is based is achieved in that casting parameters for the casting of each individual metal strand can be individually set and regulated. When casting a single wide metal strand, this includes the synchronous setting and control of the corresponding casting parameters and the individual setting and control of the corresponding casting parameters when casting two metal strands in parallel. Casting parameters that fundamentally guarantee the individually adjustable and controllable casting of each metal strand are the oscillation parameters of the mold of each individual metal strand on the oscillating device and the casting speed or the withdrawal speed of each individual metal strand.

A further flexibility in the production possibilities results from an individual adjustability of the cross-sectional format of each metal strand to be cast within certain specified values.

The casting method according to the invention is preferably characterized in that, for casting a single wide metal strand, a single mold is inserted into the continuous casting installation and is supported on at least two synchronously operated oscillating devices, and the cast metal strand is supported and guided in two synchronously operated strand guides and that for the simultaneous casting of two narrower metal strands, two mutually independent molds are inserted into the continuous casting plant and are supported on at least one oscillating device operated independently of the further oscillating device, and the cast metal strands are supported and guided in strand guides operated separately from one another.

Further advantages and features of the present invention result from the following description of non-restrictive exemplary embodiments, reference being made to the accompanying figures, which show the following:

Fig. 1 shows a longitudinal section through an inventive. 2 a plan view of the arrangement of two molds for the independent casting of two steel strands, FIG. 3 a sectional view of the molds and of the oscillating devices for the independent casting of two steel strands along the section line BB in FIG. 2, Fig. 4 is a sectional view of the mold and the oscillating devices for casting a wide steel strand in a representation analogous to Fig. 3, Fig. 5a is a circuit diagram for the control of the oscillation of the oscillating devices when casting two independent steel strands, Fig. 5b is a circuit diagram for the Regulation of the oscillating movement of the oscillating devices when casting a wide steel strand, 6 shows a tundish in the operating position above a mold for casting a wide steel strand, FIG. 7 shows a tundish in an operating position over two molds arranged next to one another for casting two narrower steel strands, FIG. 8 shows the strand guide according to the invention in a sectional view transverse to the transport direction of the Steel strand, Fig. 9 shows the arrangement of two continuous casting plants according to the invention with partially raised drive units, Fig. 10 shows a circuit diagram for the synchronization of the strand guides when casting two narrower steel strands, Fig. 11 shows a spray nozzle arrangement and a spray pattern when casting a wide slab, Fig. 12 a spray nozzle arrangement and a spray pattern when casting two narrower slabs, Fig. 13, two flame cutting devices for cross-cutting cast steel strands in a plan view, Fig. 14, a cross conveyor for removing a wide slab from the outlet roller table of the strand Casting plant, Fig. 15 a cross conveyor for removing two slabs from the outlet roller tables of the continuous casting plant, Fig. 16 a start-up line for closing a mold for casting a wide steel strand, Fig. 17 a start-up line for closing two molds for simultaneous casting of two metal strands.

A continuous slab caster according to the invention for the optional casting of a single wide steel strand or two, in contrast, narrower steel strands is shown schematically with its essential system components in FIG. 1 in a longitudinal section of the system. In the sequence of the production steps of one or two steel strands with a slab cross-section, this continuous caster essentially comprises the following components and functions:

Starting from a ladle 1 for receiving a batch of liquid steel, the molten steel flows through a shadow pipe.2 quantity-controlled into a distribution vessel 3. From there the steel melt is introduced quantity-controlled through a number of immersion pouring pipes 4 into one or two cooled and oscillating molds 5, where the solidification of the molten steel begins on the mold inner walls and a steel strand 6 is formed in accordance with the shape given by the mold inner walls with a continuously growing strand shell and a liquid core. The mold 5 is supported on an oscillating device 7, from which a predetermined oscillation movement which is significantly influenced by the casting cross-section, the casting speed and the steel quality of the molten steel to be cast is transmitted to the mold 5. After leaving the mold 5, the steel strand 6 directed vertically downward is supported in a strand guide 8, guided and further cooled and deflected from the vertical direction into a horizontal direction. The strand guide 8 comprises roller stands 9, 10 (outer arch, inner arch) for supporting the two broad sides of the steel strand, which have a narrow stock of non-driven rollers 11 and driven rollers 12 and form a transport channel for the steel strand. Rollers 11, 12 of the two roller stands 9, 10 are combined in segments and supported in interchangeable segment frames 13 in the strand guide 8. In particular in the case of a straight mold 5, the first segment following the mold is designed as a bending zone 14. After a straightening zone, the last section of the strand guide, an exit roller table 15 connects to the strand guide 8. In the effective range of a separating device 16 for the transverse division of the steel strand which has already solidified here, the run-out roller table is designed as a flame cutting roller table 22. Flame cutters 18 are used as separating elements 17. In a downstream cross conveyor 19, the strand pieces cut to length in the separating device are removed from the area of the outlet roller table 15. Furthermore, a manipulator 20 is provided in the effective area of the outlet roller table 15 for the use of a starting strand 21, which closes the outlet opening of the mold 5 at the start of the casting process. In a continuous casting installation according to the invention for the optional casting of a wide steel strand or a maximum of two, in contrast, narrower steel strands, these essential system components are designed in a special way, as will be explained in more detail below.

An essential core component of the continuous casting installation according to the invention is the mold for casting a wide steel strand or the two molds for casting two metal strands which are narrower than the one and the oscillating devices which support and oscillate these molds. These are shown in FIG. 4 for the casting of a wide steel strand and in FIGS. 2 and 3 for the casting of two relatively smaller steel strands. 2 and 4 show with dash-dotted lines a limited space 25 in the machine head of the continuous caster for optionally receiving one mold 5 or two molds 5a, 5b, this limited space 25 in the casting direction G of the respective steel strands Support blocks 26 of the oscillating devices 7 is limited, on which the mold 5 or the two molds 5a, 5b rest. The molds can be easily removed from this space 25 by manipulation devices 27 and reinserted or exchanged. Suitable manipulation devices for this change process are either a change carriage 28 with corresponding gripping devices and with two storage spaces for the change molds or the indoor crane 30 serving the casting platform 29 (FIG. 1). The molds 5, 5a, 5b generally have two broad side walls 31 and two narrow side walls 32, 33 that can be clamped between the broad side walls.

In a mold for casting a wide steel strand 6 (FIG. 4), the two narrow side walls 32, 33 lying opposite one another are arranged at the same distance from a mold center axis 34 and enable the mold to be set symmetrically and in relation to this mold center axis 34 with corresponding narrow side adjustment devices 35, as is also the case with a conventional single-strand slab caster. The mold 5 is supported on four oscillating devices 7a, 7b which ensure the desired oscillation movement of the mold with synchronous vertical movement.

The two molds 5a, 5b for optionally casting two steel strands are supported in the common space 25, in the common space 25, on two support blocks 26 of two oscillating devices 7a, 7b running parallel to the wide side walls 31, the inner narrow side walls of the two molds are arranged closely adjacent to each other. The narrow design basically requires different embodiments of these narrow side walls 32, 33 for each of the two molds. The two narrow side walls 33 on the inside, of which only the narrow side wall of a mold is shown, are firmly positioned in their position, a cone adjustment being possible if necessary. The two outer narrow side walls 32, of which only the narrow side wall of a mold is also shown, are coupled to narrow side adjustment devices 35 and enable the adjustment of different strand widths and, if necessary, a cone adjustment. The close movement of the two molds 5a, 5b for the simultaneous casting of two steel strands 6a, 6b enables a very compact construction of the downstream strand guides and thus overall a continuous casting plant with a minimized plant width. Each of the four support blocks 26 (FIG. 2) has a number of centering devices 36 and quick coupling devices for the media supply 37 (for coolant, power supply, etc.), which are designed as well-known plug-in couplings, not shown, which have mating connections correspond to the mold or molds used in each case and thus ensure a quick and tight connection when the mold is placed directly on the support blocks 26. These quick coupling devices and centering devices are assigned to support surfaces on each support block and counter support surfaces on the molds.

Each oscillating device 7, 7a, 7b comprises a support frame 39 which is detachably attached to a bracket in the system structure 40. A drive device 41 is anchored in the support frame 39, with which a predetermined oscillation movement is applied to the support block 26. To stabilize the support block 26 in the support frame 39, the latter is connected to guide elements 42 which are formed by leaf springs.

Two of the oscillating devices 7a, 7b or 7c, 7d, which are provided together for the support and oscillation of a mold 5a, 5b for casting a narrower steel strand, are connected to a hydraulic control block 44 (FIG. 5a), which performs a synchronous oscillation movement of the two cooperating support blocks 26a, 26b or 26c, 26d. The two control blocks 44 are controlled individually by a central processing unit 45 and matched to the casting conditions of the respective steel strand. When using a mold 5 for casting a wide steel strand, all four oscillating devices 7a, 7b, 7c, 7d interact (FIG. 5b) and the associated hydraulic control blocks 44 are connected via data lines to a synchronization device 46, which is formed by a central processing unit 45 ,

In FIG. 6, a distribution vessel 3 is arranged in a casting position above a mold 5 for casting a single, wide steel strand 6. Steel melt 48, which is introduced into the distribution vessel 3 via a shadow tube, not shown, flows through an outlet opening 49 in the bottom of the distribution vessel 3 and through an immersion pouring tube 4 into the mold cavity of the mold 5. The immersion pouring tube 4 or the outlet opening 49 is a closure member 50 assigned, which is attached to the bottom of the distribution vessel. The closure member 50 consists of a hydraulically or pneumatically actuated slide, with which the feed quantity of the molten steel is regulated. Analogously, the same distributor vessel 3 is arranged in FIG. 7 above two molds 5a, 5b for the simultaneous casting of two metal strands 6a, 6b in the operating position. Each of the two molds 6a, 6b is assigned an immersion pouring tube 4 with a closure element 50 for the controlled transfer of molten steel from the common distributor vessel 3.

To ensure optimal melt distribution in the mold cavity of each mold 5, 5a, 5b and also to meet the requirements of different casting speeds and strand cross-sections, in particular different strand widths, a plurality of outlet openings 49 and associated closure members 50 are provided in the bottom of the distributor vessel 3, which are separated by vertical, Dashed lines illustrate the central axes 51a, 51b, 51c, 51 d and 51 e of the outlet openings 49. These central axes 51 a to 51 e of the outlet openings are arranged along a straight line, not shown here, which lies in the central plane of the mold. The various outlet openings 49 with the associated closure member 50 can be equipped with immersion pouring tubes 4 and activated as required. For example, it is possible to pour molten steel into the mold via a central outlet opening 49 corresponding to the central axis 51c (FIG. 6) or via two outlet openings corresponding to the central axes 51b and 51d. When simultaneously casting two steel strands 6a, 6b, depending on the chosen casting width, outlet openings 49 corresponding to the central axes 51b and 51d or corresponding to the central axes 51a and 51e can be activated. In any case, the aim is to introduce the molten steel centrally to the wide side walls and as centrally as possible to the narrow side walls and thus largely equally distributed into the mold 5 or the two molds 5a _v 5b. When changing the mold, only dip tubes according to the selected continuous casting mold should be provided on the distributor vessel. All other necessary adjustments to the continuous caster are only process-controlled.

After leaving the mold, each cast steel strand is deflected in a curved strand guide 8 from a substantially vertical casting direction into a horizontal transport direction. Two simultaneously cast steel strands 6a, 6b are, as shown in FIGS. 8 and 9, independently supported and guided in closely adjacent strand guides 8a, 8b.

Each of the independent strand guides 8a, 8b comprises a roller stand 9a, 9b for the outer arch and a roller stand 10a, 10b for the inner arch of the continuous casting plant, which essentially consist of a tight corset of driven and non-driven rollers.

The two strand guides are preferably divided into segments, while maintaining their functional independence, which comprise adjacent sections of the strand guides. 8 shows a cross section through such a segment with driven rollers 12, which form two pairs of rollers and independently support and convey the two cast steel strands 6a, 6b. The rollers assigned to the respective steel strands are coupled to drive devices 53 for determining the individual casting speed. The rollers of the outer sheet of both strand guides 8a, 8b are supported in a common support frame 54 or segment frame supporting both strand guides and form the fixed side of the strand guide. The rollers of the inner arch are supported separately for each strand guide 8a, 8b in independent roller carriers 55a, 55b and fastened in the common support frame 57 or segment frame via articulated connections 56a, 56b. The independent roller carriers 55a, 55b can be displaced vertically on guides of the supporting frame (not shown in more detail) and can be pressed against the respective steel strand with pressure medium cylinders 58a, 58b between the roller carriers 55a, 55b and the supporting frame 57, so that a predetermined torque can be transmitted. The support frame 54 of the outer arch and the support frame 57 of the inner arch are fixed in the segment via lateral tensioning devices 59 and correspond to the usual structure of a strand guide segment.

9 shows a very closely adjacent arrangement of two continuous casting plants of the type according to the invention, in which the overall plant width is minimized. In this case, the drive devices 53 of the driven rollers 12, which, as in the case of the two outer strand guides, protrude laterally to a large extent, are arranged via planetary gear 60, coupled angular gear 61 and via cardan shafts 62 in a raised position laterally above the two adjacent two inner roller stands 8b, 8a. It is also within the scope of protection of the invention if only one of the two continuous casting plants is designed according to the invention.

When casting a wide steel strand which extends in its width across both strand guides 8a, 8b, as shown in FIG. 10, the drive devices 53a, 53b of the driven rollers 12a, 12b are operated by a synchronization device 46 for setting synchronous conditions (Roller speed) controlled. Equally, the contact pressure of the driven rollers against the steel strand is adjusted by applying the same or synchronizing the control blocks 63 and thus the pressure medium cylinders 58a, 58b via the synchronization device 46 or central processing unit. The pressure medium cylinder 58a acts between the roller carrier 55a and the common support frame 57 and the pressure medium cylinder 58b acts between the roller carrier 55b and the common support frame 57 and thus enables individual adjustment, in particular of the driven rollers, to the steel strand.

In the strand guides 8, 8a, 8b, the steel strand, which is still liquid in the core area, is continuously cooled to a strand temperature which ensures solidification and enables strand separation. Strand cooling is particularly important in the first strand guide segments, especially in the bending zone. FIG. 11 shows a spray nozzle arrangement for strand cooling tailored to the casting of a wide steel strand, and FIG. 12 shows a strand cooling tailored to the casting of two correspondingly narrower steel strands.

Along the strand guide, spray nozzles 65a, 65b, 65c, 65d, 65e are arranged in a plurality of rows running in the casting direction, preferably as shown in five rows, which can be acted upon individually or in groups. When casting a steel strand 6 of maximum width, all five spray nozzles or spray nozzle rows are in use (FIG. 11) and ensure uniform coolant application to the strand surface transversely to the casting direction or strand transport direction. When casting two steel strands 6a, 6b maximum possible width _; the two outer spray nozzles 65a, 65b and 65d, 65e in operation and the middle spray nozzle 65c is switched off (FIG. 12). Only the left or right steel strand 6a or 6b can be cast. Accordingly, only the two spray nozzles assigned to this line are activated. An adaptation to every possible operating situation is therefore basically possible.

In the outlet area of the continuous caster according to the invention there are two outlet roller tables 15a, 15b, on which either a wide slab, which is supported on both outlet roller tables 15a, 15b, or two slabs, in contrast, narrower, each of which is assigned to one of the roller tables, after leaving the Separator are moved. In Fig. 14 is the situation with the cross conveyor a wide slab and in Fig. 15 the situation with the cross-conveyance of two, in contrast, narrower slabs is illustrated.

In the horizontal run-out area of the continuous casting plant, the two run-out roller tables 15a, 15b in the effective area of two separating devices 16a, 16b are designed as flame cutting roller tables 22a, 22b in a conventional manner. The two cutting devices designed as flame cutting machines are arranged one behind the other in the strand transport direction indicated by arrows at a distance which is sufficient to be able to cut one of the two cast steel strands along this path with a maximum casting width. Each of the separating devices 16a, 16b is assigned to a flame cutting roller table 22a, 22b and thus to one of the two steel strands. In the production of only one wide steel strand, which rests on both roller tables at the same time, which is not shown here, the cross-cutting takes place with only one of the two separating devices, while the second separating device is in a waiting position.

The two separation devices 16a, 16b are identical. They each consist of a portal 81 which can be moved on lateral carriageways 80a, 80b parallel to the strand transport direction and bridges the two flame cutting roller tables 22a, 22b. On the cross member 82 of the portal 81, two separating elements 17 are slidably arranged on horizontal guides 83. The separating elements 17 of a separating device can be used both for transverse dividing a wide strand or one of two steel strands that are narrower in comparison.

As shown in Fig. 14, a wide slab is located in a removal area of the outlet roller table, in which a cross conveyor 19 is arranged, which comprises two pushing hooks 70 and two shifting drive 71 which move the slab from a position A to the outlet roller tables 15a, 15b in a position B on a further conveyor roller table 72a, on this conveyor roller table the slab is removed from the plant area and fed to further processing devices (not shown) or to a storage place.

In Fig. 15, a narrow slab is shown on each of the roller tables in the removal area of the outlet roller tables 15a, 15b, where the two slabs with the transverse conveyors 19a, 19b are moved in directions leading away from one another on conveyor roller tables 72a and 72b. This is done with the Sliding drives 71a, 71b and the pusher hooks 70a, 70b from the positions A, A 'on the outlet roller tables 15a, 15b in positions B, B ^' on the respectively adjacent discharge roller tables 72a or 72b.

To start the casting process, the individual mold for casting a wide steel strand or the two molds for casting two, in contrast, narrower steel strands on the output side of their mold cavity must be closed by a start-up strand, which is usually inserted along the strand guide from below into the mold.

As shown in FIG. 16, a starting strand head 75, which is articulated to two starting strands 21a, 21b, projects into the mold cavity of a continuous casting mold 5 for casting a wide steel strand and closes it off on the output side. The driven rollers 12a, 12b of the two strand guides 8a, 8b, which are indicated by dash-dotted lines, access the two starting strands 21a and 21b in a controlled, synchronized manner by the synchronization device 46 and thus prevent the starting strand from tilting during the conveying movement in the two strand guides it.

17 illustrates the situation when two or more metal strands of smaller width start to pour together or separately: a start-up strand 21a closes the exit end of the continuous casting mold 5a with the start-up strand head 75a, and analogously the start-up strand 21 b closes the exit end of the continuous casting mold with the start-up strand head 75 b 5b. The starting strand 21a is assigned to the strand guide 8a and is individually moved in the strand guide by the driven roller 12a. Completely independently of this, the start strand 21b can be conveyed in the strand guide 8b by the driven rollers 12b. This means that each individual line can be started independently of the other.

Claims

claims

1. Continuous casting plant for the optional casting of a wide metal strand (6) or a maximum of two metal strands (6a, 6b) that are narrower in comparison, the at least one distributor vessel (3), a mold (5) supported on an oscillating device (7) and a downstream strand guide (8 ), characterized in that the continuous casting plant has a space (25) for optionally receiving one (5) or two molds (5a, 5b) and two oscillating devices (7a, 7b) and two strand guides (8a, 8b) with associated Drive devices (41) for separate and synchronous operation of the oscillating devices (7a, 7b) and the strand guides (8a, 8b) are arranged.

2. Continuous casting installation according to claim 1, characterized in that each of the two oscillating devices (7a, 7b) is assigned a drive device (41) for generating an oscillating movement and these drive devices (41) are connected to a synchronization device (46) for setting synchronous conditions of the oscillating movement are.

3. Continuous casting installation according to claim 2, characterized in that the synchronization device (46) for setting synchronization conditions of the oscillation movement is formed by a central processing unit (45).

4. Continuous casting installation according to one of the preceding claims, characterized in that each oscillating device (7a, 7b) comprises a hydraulic actuator (41) and a control block (44) which is connected to a computing unit (45) via signal lines.

5. Continuous casting installation according to one of the preceding claims, characterized in that each oscillating device (7a, 7b) comprises a support block (26, 26a, 26b, 26c, 26d) for supporting a mold (5, 5a, 5b) and on the support surface each support block and the corresponding counter support surface of the mold quick coupling devices (37) for the media supply (coolant, Power, signal lines, etc.) and at least one centering device (36) are arranged.

6. strand guide according to one of the preceding claims, characterized in that on a casting platform (29) at least one manipulation device (27) for performing a mold change, preferably a change carriage (28) is arranged.

7. Continuous casting installation according to one of the preceding claims, characterized in that the two parallel strand guides (8a, 8b) comprise roller stands (9a, 9b, 10a, 10b) with driven (12, 12a, 12b) and non-driven rollers (11) that the driven rollers are connected to drive devices (53) and the drive devices of the rollers of both roller stands (9a, 9b, 10a, 10b) are connected to a synchronization device (46) for setting synchronous conditions of the driven rollers (12, 12a, 12b) are.

8. Continuous caster according to claim 7, characterized in that the synchronization device (46) for setting synchronization conditions of driven rollers in the strand guide is formed by a central processing unit (45).

9. Continuous casting installation according to claim 7 or 8, characterized in that the rollers (11, 12, 12a, 12b) or pairs of rollers of both roller stands (9a, 9b, 10a, 10b) interacting in the casting of a wide metal strand in a common support frame (54) or segment frames are supported.

10. Continuous casting installation according to claim 9, characterized in that the relatively movable roller of a pair of rollers or the relatively movable rollers of a group of roller pairs in each of the two roller stands (9a, 9b) are fastened to independent roller carriers (55a, 55b) which are mounted in the common support frame ( 57) or segment frames are supported.

11. Continuous casting installation according to claim 7, characterized in that each drive device (53) of a driven roller (12a, 12b) is connected to it via a cardan shaft (62) and laterally outside of the two next to one another extending roller stands (9a, 10a and 9b, 10b) of the strand guides (8a, 8b) is arranged.

12. Continuous casting installation according to claim 11, characterized in that in the case of strand guides (8a, 8b) arranged in pairs next to one another, at least two continuous casting installations, the internal driven rollers (12b, 12a) via a planetary gear (60) and an angular gear (61) with the drive device ( 53) and the drive device is arranged in a raised position laterally above the two adjacent roller stands of the strand guides (8b, 8a).

13. Continuous casting installation according to one of the preceding claims, characterized in that each strand guide (8a, 8b) is assigned an independent separating device (16a, 16b) for cross-cutting one of two narrow metal strands (6a, 6b) cast in parallel and each of these separating devices carries at least one separating element (17), preferably a cutting torch.

14. Continuous casting installation according to claim 13, characterized in that two separating devices (16a, 16b), each of which crosses both strand guides (8a, 8b) or flame cutting roller tables (22a, 22b), are arranged one behind the other in the strand conveying direction.

15. Continuous casting installation according to claim 13 or 14, characterized in that at least one of the two separating devices (16a, 16b) for cross-cutting a wide metal strand (6) is equipped with two interacting separating elements (17).

16. Continuous casting installation according to one of the preceding claims, characterized in that the strand guides (8a, 8b) and the separating devices (16) are arranged downstream of roller conveyors (15a, 15b), to which a transverse conveyor device (19, 19a, 19b) for changing the transport direction is assigned to pieces of slabs (slabs) to be derived transversely to the strand transport direction.

17. Continuous casting installation according to one of the preceding claims, characterized in that the distributor vessel (3) has a plurality of spaced apart has arranged outlet openings (49) for molten metal, that the outlet openings are assigned closure members (50) and these closure members are connected via signal lines to the central processing unit (45) and are designed to be activatable depending on the casting format of the downstream mold (5, 5a, 5b) ,

18. Continuous caster according to one of the preceding claims, characterized in that two starting strands (21a, 21b) for the casting start are guided through the strand guide (8a, 8b) into the mold (5, 5a, 5b) and these are used when two molds (5a, 5b) are equipped with separate start-up strand heads (75a, 75b) and, when using a mold (5), are equipped with a common start-up strand head (75).

19. A method for selectively casting a wide metal strand or two metal strands which are narrower in comparison in a continuous casting installation, wherein an at least partially solidified metal strand is formed in a mold and the at least partially solidified metal strand is supported and guided in a subsequent strand guide, characterized in that casting parameters for the casting of each Metal strands can be individually adjusted and regulated both when casting a metal strand and when casting two metal strands in parallel.

20. The method according to claim 19, characterized in that at least one oscillation parameter of the mold for the casting of each individual metal strand and the casting speed of each individual metal strand are individually adjustable and controllable.

21. The method according to claim 19 or 20, characterized in that • for casting a single wide metal strand, a single mold is inserted into the continuous casting installation and is supported on at least two synchronously operated oscillating devices, and the cast metal strand is supported and guided in two synchronously operated strand guides, and • For the simultaneous casting of two narrower metal strands, two molds which are independent of one another are inserted into the continuous casting installation and are supported on at least one oscillating device which is operated independently of the further oscillating device and the cast ones Metal strands are supported and guided in strand guides operated separately from one another.