EP3291933B1 - Casting and rolling assembly and method for operating the same - Google Patents

Description

The invention relates to a casting-rolling plant for small-scale annual production of metal strips, wherein the metal strip passes through the casting-rolling plant in a conveying direction, comprising a casting machine with a vertical outlet mold for producing a cast strand and one of the mold in the conveying direction downstream strand guide for deflecting the casting strand from the vertical to the horizontal, one of the strand guide in the conveying direction downstream connection system comprising at least one straightening device for pulling the casting strand from the strand guide and a separator, in particular scissors, and a furnace for heating the casting strand and a downstream of the connection system in the conveying direction rolling mill for rolling the casting strand to the metal strip. Furthermore, the invention relates to a method for operating such a casting-rolling plant.

A casting-rolling plant of the generic type is known from EP 0 846 508 A1 and from the EP 0 535 368 B1 known. Similar and other solutions reveal the EP 0 099 076 B1 , the EP 2 571 640 B1 , the WO 2013/113832 A1 , the DE 10 2010 022 003 A1 , the AT 292 937 B , the CH 595 165 A5 , the DE 12 33 542 B and the CH 407 422 A ,

So-called CSP plants are built and operated in conventional embodiments as Vertical Solid Bending (VSB) plants or as Vertical Liquid Bending (VLB) plants. Such plant types are designed for productions of more than 1 million tons per year.

In particular, for small annual production of less than 800,000 tons, with a dimension of, for example, 1300 mm x 45 mm, special measures are necessary to produce a high-quality strip with the lowest possible investment costs and low operating costs.

The invention is therefore the object of developing a generic casting-rolling device so that the functionality of the system can be increased, in particular, it should be possible to produce high quality metal strip at low investment and operating costs.

The solution of this object by the invention is characterized in that the strand guide has a single or two roller segments, wherein the rollers provided for strand guidance are free of a drive.

In this case, the connection system between steel mill and rolling mill is designed in particular such that the strand at the kiln inlet has a sufficiently high average temperature for the subsequent rolling operation. As a result, the furnace in normal casting operation no longer needs to heat the strand for the subsequent rolling mill or only in exceptional need.

In the presence of two roller segments in the strand guide these are preferably formed substantially identical.

The strand guide is preferably designed to bend the cast strand so that it has a minimum radius of curvature of 2100 mm.

The strand guide preferably has the shape of a clothoid, at least in sections.

The mold is preferably formed vertically or as a curved mold.

The length of the mold is preferably at most 1100 mm, more preferably between 900 mm and 1000 mm.

The height of the strand guide without mold preferably has a maximum height of 3 m. Thus, the much lower than previously known comparable facilities.

The connection system preferably has a separating device, in particular a pair of scissors, which is arranged between the directional driver and the oven. The straightening unit and the scissors are constructed constructively as "straightening shears".

Since the furnace does not have to heat the strand in the normal casting operation, it can be built very short (less than 100 m). It must be at least as long that a slab fits all the way in and the slab can be accelerated from the casting speed to the rolling speed (kiln length = slab length + acceleration length).

The oven therefore advantageously has a minimized length. The length consists of the slab length, the acceleration length and the additional heating length to compensate for the heat losses.

The connection system furthermore has a cold-string delivery unit, preferably a cold-rod rocker, with integrated insulation.

The strand guide preferably ends before the tangent point; this is preferred for low production to obtain a minimum energy requirement.

The strand guidance can also end in or behind the tangent point. This is advantageous in higher productions.

The straightening and driving unit preferably has driven rollers on the top and bottom of the slab. This is advantageous because of the doubling of the withdrawal forces.

The oven is preferably shorter than 100 m. The furnace has, according to one embodiment, at least one inductive heating element. Furthermore, can be provided that the furnace at least one heat hood upstream or downstream in the conveying direction.

The heating unit is thus specially adapted to the requirements of the short casting machine. It preferably consists of a short furnace (less than 100 m, for example also 60 m with a band length of 50 m) or, alternatively, an inductive heating with a subsequent passive heat hood.

The cold strand can be carried away between separator and oven upwards. In casting this room is protected by a sliding heat hood against heat loss. For discharging the cold strand this heat hood is pushed over the adjoining oven.

The method for operating such a casting-rolling plant is carried out according to the invention in that the casting strand cast in the casting machine is fed into the rolling mill without further heating in the furnace and rolled therein.

Here, it is preferably provided that the cast casting strand is cooled in the strand guide so that it is completely solidified when reaching the straightening driver.

Preferably, the cast casting strand is cooled in the strand guide so that it is completely solidified 500 mm to 10 mm (target interval) in the conveying direction before the last roll of the strand guide. This approach is particularly advantageous in terms of low investment and operating costs.

The solidification fraction FS (= fraction solid) at the final solidification is preferably in the range of FS = 0.9 to FS = 1.0, preferably exactly at FS = 1.0.

The sump tip is thus selectively placed in the target interval, which is done by controlling the casting speed and / or the cooling volume flows.

The segments of the strand guide can be changed to increase the radius of curvature, which is advantageous for crack-sensitive steels or larger thicknesses. Thus, a simple extension of the Micro-CSP system on higher quality steels or higher production is possible.

The oven inlet temperature is preferably greater than 1050 ° C. Due to the short casting machine and the compact design of the connection system, the strand is optimally prepared at this furnace inlet temperature so that it does not have to be further heated in the furnace for the subsequent rolling mill.

Carbon steels with low and average carbon contents are preferably processed. The dimensions are preferably between 40 and 60 mm, preferably between 45 and 55 mm; but also other steels with comparable dimensions are preferably processed.

The invention thus relates to the linking of a steelworks with a rolling mill by a small casting machine (micro-casting machine) and a connection system.

The compact design of the casting machine with the connection system realizes a low capital expenditure with low operating costs. This is achieved through components of small dimensions and short distances. Additionally, for low cost production conditions, a high exit temperature of the cast strand is required at the end of the caster. Due to the compact design according to the invention, little energy is lost, so that energy must be supplied in the subsequent furnace system only in special production conditions.

Here are mainly carbon steels with low and medium carbon content with outlet thicknesses of the strand guide the casting of 40 to 60 mm, preferably 45 to 55 mm, cast, but also other steels with comparable dimensions.

Accordingly, the invention provides a link between steel mill and rolling mill by the inclusion of a suitable casting machine with connection system as key components. The link provides the essential components ladle turret, distributor, casting machine with mold, straightening unit, shears, Kaltstrangausfördersystem and furnace systems. Key component is a casting machine with short strand guide and a small distance to the furnace.

In particular, in the present case, the components behind the caster - such as straightening unit, scissors, Kaltstrangausfördersystem and furnace systems - are addressed as a connection system.

Fig. 1

zeigt schematisch eine Gieß-Walz-Anlage, wobei eine Gießmaschine ohne angetriebene Segmente eingesetzt wird,

Fig. 2

zeigt eine tabellarische Auflistung, in der für verschiedene Werkstoffe zulässige Dehnungen, minimalste Krümmungsradien und maximale Strangdicken aufgezeigt sind,

Fig. 3

zeigt eine Strangführung mit Kokille und einer ersten Richtteiberrolle vor dem Tangentenpunkt T,

Fig. 4

zeigt eine Strangführung mit Kokille und einer ersten Richtteiberrolle im Tangentenpunkt,

Fig. 5

zeigt eine Strangführung mit Kokille und einer ersten Richtteiberrolle nach dem Tangentenpunkt,

Fig. 6

zeigt eine Strangführung mit einem Segment und mit zwei Segmenten,

Fig. 7

zeigt schematisch produktionsabhängige Bauformen der Strangführung,

Fig. 8

zeigt ein Verbindungssystem als Baueinheit mit kompaktem Richttreiber und Schere,

Fig. 9

zeigt eine Kaltstrang-Wippe als passive Verlängerung des Ofens im Gießbetrieb,

Fig. 10

zeigt eine Kaltstrang-Wippe als passive Verlängerung beim Transport des Kaltstrangs,

Fig. 11

zeigt eine verschiebbare Wärmehaube bei der Kaltstrang-Ausförderung,

Fig. 12

zeigt die verschiebbare Wärmehaube während der Produktion und

Fig. 13

zeigt einen Ablaufplan zur Prozesssteuerung beim Walzenwechsel.

In the drawings, embodiments of the invention are shown.

Fig. 1

shows schematically a casting-rolling plant, wherein a casting machine is used without driven segments,

Fig. 2

shows a tabular list, in which for various materials admissible strains, minimum radii of curvature and maximum strand thicknesses are shown,

Fig. 3

shows a strand guide with mold and a first Richtteiberrolle before the tangent point T,

Fig. 4

shows a strand guide with mold and a first Richtteiberrolle in the tangent point,

Fig. 5

shows a strand guide with mold and a first Richtteiberrolle after the tangent point,

Fig. 6

shows a strand guide with a segment and with two segments,

Fig. 7

shows schematically production-dependent designs of the strand guide,

Fig. 8

shows a connection system as a unit with a compact straightening driver and scissors,

Fig. 9

shows a cold-strand rocker as passive extension of the furnace in the casting operation,

Fig. 10

shows a cold-strand rocker as a passive extension during transport of the dummy bar,

Fig. 11

shows a sliding heat hood in the cold-strand discharge,

Fig. 12

shows the sliding heat hood during production and

Fig. 13

shows a flow chart for process control during roll change.

In Fig. 1 is a casting-rolling plant 1 for the production of a metal strip 2 can be seen. The plant has a casting machine 3, in which liquid metal emerges from a mold 14 vertically downwards and is deflected along a strand guide 4 from the vertical in the direction of the horizontal. The material of the belt or the belt itself is conveyed in a conveying direction F through the system 1.

The plant 1 also has a rolling mill 8. Between the casting machine 3 and the rolling mill 8, a connection system 5 is arranged. The connection system 5 comprises a straightening driver 6, a subsequent separating device, preferably a pair of scissors 9, and an oven 7; Furthermore, a cold-strand rocker 10 is present.

Registered in Fig. 1 nor the tangent point T at which the cast metal strip 2 opens into the horizontal.

It is essential that the strand guide 4 has a single roller segment or only two roller segments, with their rollers provided for strand guidance free are from a drive. Rather, the cast metal strip is pulled out of the casting machine 3 by the straightening device 6.

Due to the low (year) production aspired, pans with smaller volumes and therefore compact ladle turrets and distributors can be used. Due to the small pan sizes, a rigid ladle turret can be used.

Alternatively, a pan transport via ladle is possible; Another alternative possibility consists of fixed, preferably two, parking spaces for the pans and in a transport by means of a steelwork crane.

With regard to mold 14, the following is noted: The standard CSP plants for production quantities in excess of one million tonnes per annum usually use a 1,100 mm long hopper die for casting speeds up to 8 m / min.

For the casting machine in compact design shortened funnel coasters can be used, whose length is between 900 and 1100 mm, depending on the preferred casting speed. If necessary, the mold can be built even shorter. This saves investment and operating costs at the same time.

With regard to the strand guide 4, the following is of importance: According to the present problem of low production in conjunction with the compact design of the mold and the strand guide according to the invention, a casting machine 3 which is shorter than conventional advantageously results. The strand guide 4 ends in the arc of the strand guide in front of the straightening device 6. The solidification of the strand takes place before the straightening 6, ie within the strand guide 4. This is necessary because otherwise the necessary extraction forces for transporting the strand can not be transferred.

In order to keep capital expenditure and operating costs particularly low, the average temperature of the strand at the end of the strand guide must be as high as possible his. This is achieved by the smallest possible distance of Enderstarrungsposition to the last role of the strand guide and by the most balanced temperature profile in the strand.

Due to the dependence on different production campaigns, because of fluctuating process parameters such as casting temperature, cooling flow rates, radial roll distances (= jaw widths) and casting speeds but also due to analysis fluctuations, a consistent position of solidification is prevented. Therefore, a final solidification in the range of 10 mm to 500 mm, the target interval, should be aimed at before the last roll of the strand guide. The area of final solidification is defined with a solidification fraction of FS = 0.9 to 1.0, ideally FS = 1.0.

Since the kiln inlet temperature drops sharply with shorter swamp lengths (see the comments below on the kiln), the swamp tip must be within the specified target interval in order to keep the kiln length short. This is achieved by regulating the casting speed and / or the cooling volume flows.

The design of the hopper mold - vertical or curved - has an influence on the design of the upper part of the strand guide.

Possible designs of the mold are the vertical mold, d. H. the strand guide begins perpendicular or with a large radius of curvature (clothoids). Furthermore possible is a bent mold, d. H. the strand guide has a same radius of curvature or a decreasing radius of curvature.

The radius of curvature of the strand guide, starting from the radius present at the mold outlet, preferably up to the minimum radius of curvature (see Fig. 2 ) decreased. Then there is the possibility to increase the radius of curvature to the end of the strand guide again, such. B. in the double clothoid.

The use of the minimum radius of curvature within the strand guide leads to a minimized height. In addition, this results in a short strand guide length and thus a small distance to the straightening drivers.

The minimum radius of curvature in the strand guide depends on the material and the strand thickness. It depends on the maximum allowable elongation of the outer fiber of the curved strand. For this purpose, refer to the illustration in Fig. 2 directed.

Similarly, larger strand thicknesses can be cast for larger radii of curvature in the strand guide.

In this case, the design of the strand guide is determined by the production or casting speed, the largest strand thickness to be cast and the material to be cast.

At low production (eg 500,000 tons per year) the strand guide 4 ends before the tangent point T; this situation is in Fig. 3 shown.

At higher production (eg 800,000 tons per year) the strand guide 4 ends at or after the tangent point T; this situation is in the FIGS. 4 and 5 shown. Here can in the strand guide z. B. a curve of the radii of curvature can be used in the form of a double clothoid.

For small designs, it is advisable to create the strand guide 4 from only a single segment (plus straightening unit or straightening driver). For larger designs, however, two segments are provided. In Fig. 6 these two possibilities are illustrated.

Drives within the strand guide are not necessarily required because the extraction of the strand 2 is taken over by the located at the end of the strand guide 4 straightening and driving unit 6.

For smaller productions or casting speeds, a lower strand guide length is required.

For medium production or casting speeds, a slightly longer strand guide length is required.

For higher production or casting speeds, a longer strand guide length is required.

In Fig. 7 is the respectively preferred arrangement of strand guide 4 and straightening 6 depending on the production volume and with respect to the tangent point T shown.

In order to lose as little temperature as possible by radiation, the distance between the last supported roll and the straightening unit must be as small as possible. Cost-reducing is that the strand guide 4 has no driven rollers. In addition, the structurally required distance between the last role and the straightening unit can be secured by insulation and radiation protection components against energy losses.

To expand the product range and increase production, the following should be noted: If the production range of an existing micro-CSP plant for low and medium carbon is to be easily extended to crack-sensitive steels or larger thicknesses (which corresponds to a larger production), the minimum radius of curvature must be increased be increased by exchanging the segments.

This is illustrated by the following example:
At the maximum possible elongation, a radius of curvature of 2,100 mm is desired for a thickness of 40 mm. It follows: $$2100\mathrm{mm}/40\mathrm{mm}\approx 2400\mathrm{mm}/45\mathrm{mm}$$

Accordingly, a minimum radius of curvature of 2400 mm is required for the same elongation for crack-sensitive steels of 45 mm thickness.

The strand guide must be designed with the specified system height and the position of the straightening driver. This can be achieved with the help of an already curved hopper mold and a modified strand guide.

The straightening device 6 and the separating device (scissors) can be configured as a straightening-scissors-unit 11 (see Fig. 8 ).

For further general cost reduction and to achieve faster segment switching times, the straightening and driving unit and the segments can preferably be changed separately, so that the straightening and driving unit does not have to be changed with the segment change.

The straightening and driving unit 6 consists of at least two roller pairs with drive for transmitting the forces for strand transport. To double the pull-out forces, the rollers are driven on the top and bottom.

In order to shorten the distance between the straightening unit and the shears, straightening drivers and scissors can be combined as a compact unit 11 (as a "straightener") (s. Fig. 8 ). Alternatively, the "straightener" can be performed with a driven straightening roller in front of the scissors and a straightening roller behind the scissors. Due to the then higher strand temperatures, the shear requires a lower shear force. This allows the scissors and their drive to be built smaller and more compact.

If the cold-rod inlet and Ausfüdelzone between straightening 6 and the scissors 9, this area is again as short as possible to build and to provide with insulation and radiation protection components.

In the interstices of the system components, energy losses are reduced through the installation of insulation and radiation protection components. The scissors 9 can be protected against the thermal radiation of the high surface temperatures of the strand by insulation and radiation protection components.

The proposed system furthermore has a cold-extruded discharge unit, preferably a cold-extruded rocker 10 (see, for this, the FIGS. 9 and 10 ).

The cold-strand threading unit may be located between the directional control unit 6 and the scissors 9 or preferably after the scissors 9.

If the cold strand is separated from the strand head after the shear 9, this area must be as short as possible in order to lose as little energy as possible. All free routes can be covered by insulation and radiation protection components.

In one possible embodiment, the cold strand can be transported via a rocker 10 above the furnace 7 and deposited there. The rocker 10 is then constructed so that it lies in the normal casting above the furnace 7 (see Fig. 9 ). Your over the oven 7 in the direction of casting machine 3 extending length is protected downwards by insulation and radiation protection components. These insulations serve firstly to protect the rocker 10 against the high temperature of the strand, and secondly to reduce the energy losses of the strand. On the side walls of the rocker 10 more insulation and radiation protection components are present, which extend into the vicinity of the hall floor. As a result, the space between the scissors 9 and 7 furnace is formed into a kind of heat hood: this allows a passive extension of the furnace. 7

In an alternative embodiment (see FIGS. 11 and 12 ), the cold strand 12 is conveyed away between the scissors 9 and the kiln inlet to the hall ceiling. Also in this embodiment, the distance between scissors 9 and kiln inlet is after the entry and removal of the cold strand 12 to protect against energy loss. Here is a heat hood 13 z. B. over the oven 7 away or rotated by a tilting device over the oven 7. In addition, protection for adjacent mechanical or electrical equipment, such. As the scissors 9, to install against the high thermal radiation of the furnace.

For all transport rollers between the casting machine and the kiln inlet, non-cooled rolls can be used, preferably furnace rolls. They remove less energy from the strand underside during roller contact.

The furnace system can be heated with fossil fuels or electrically, in particular inductively. There are also combinations of both variants possible. Alternatively, an inductive heating with subsequent passive heat hood can be used to compensate for the temperature profile, or only a passive heat hood.

The furnace must be at least long enough for a slab to fit all the way in and then be accelerated to the required rolling speed (about 18 m / min) from the incoming casting speed, preferably 4 to 5 m / min. For a slab length of approx. 50 m, a 60 m long stove is sufficient.

The following applies: The acceleration length is the length in order to accelerate the slab from the casting speed to the rolling speed.

For the furnace length, the following applies: The minimum furnace length is the slab length plus the acceleration length.

To compensate for roll change times, this minimum furnace length may need to be extended (see below for roll change times).

Only if the furnace inlet temperature is below the minimum allowable rolling temperature, the furnace must actively heat the slab to this temperature.

d_Sumpf

:= verkürzte Sumpflänge

d_Abstand

:= nicht isolierte Abstand zwischen Ende Gießmaschine und Ofen

d_AbstandIso

:= isolierte Abstand zwischen Ende Gießmaschine und Ofen

The following example is given:
To heat a 1,050 ° C hot slab at an oven temperature of 1,100 ° C, the following additional oven lengths are required: 1 m shorter swamp length ≈ 28 m additional oven length 1 m uninsulated distance between casting machine and kiln inlet ≈ 5 m additional furnace length 1 m isolated distance between casting machine and kiln inlet ≈ 2 m additional furnace length With

d _swamp

: = shortened sump length

d _distance

: = uninsulated distance between end of caster and oven

d _distanceIso

: = isolated distance between end of casting machine and oven

This results in the furnace length additionally required for heating: $$\mathrm{additionally\; required\; oven\; length}\approx 28*{\mathrm{d}}_{\mathrm{swamp}}+5*{\mathrm{d}}_{\mathrm{distance}}+2*{\mathrm{d}}_{\mathrm{AbstandIso}}$$

From this approximation formula it becomes apparent:
The distance between the end of the casting machine, in particular the end of the target interval, and the kiln inlet is to be kept as low as possible.

The sump tip should be placed at the end of the casting machine (= in the target interval).

Between the end of the casting machine, in particular the end of the target interval, and the kiln inlet, the strand or the slab is to be protected against energy losses by means of insulation or radiation protection components.

This causes the strand or slab to enter the furnace more hotly.

Thus, the oven can be made shorter (lower investment costs).

In the standard production mode, the strand or the slab does not have to be actively or less heated (lower operating costs).

To determine the exact temperature curve in the furnace, mathematical-physical models can be used.

Regarding the roller change times, the following should be noted:
In the rolling process, the rollers wear and must, depending on productivity and roll material, for. B. be changed every five hours. The aim is to perform this roll change without casting break, since the risk of breakthrough increases when re-casting and units should be replaced prematurely.

In order to perform the roll change without casting break, sufficient time must be created between the end of the previous strip and the rolling of the new slab. For this purpose, on the one hand, the rolling of the previous band can be accelerated and, on the other hand, the casting of the new slab can be slowed down. For this purpose, the casting speed is reduced.

So that the temperature does not drop too much, the cooling in the casting machine is reduced according to the casting speed. If the slab nevertheless becomes so cold that it can no longer be brought to the required rolling temperature in the oven, it must be chopped with scissors. The required roll change times are a criterion for determining the required furnace length.

By knowing the required rolling speed, the casting speed and the temperature control in the casting machine can be optimized so that the maximum possible strand temperatures are achieved. This reduces the energy consumption in the oven and reduces operating costs.

In Fig. 13 For this purpose, a flow chart for process control during roll change is shown.

LIST OF REFERENCE NUMBERS

1

Casting and rolling plant

2

Metal band / slab

3

casting machine

4

strand guide

5

connection system

6

Straightening / straightening and driving unit

7

oven

8th

rolling mill

9

Separating device (scissors)

10

Dummy bar rocker

11

Straightening scissors assembly

12

dummy bar

13

movable heat hood

F

conveying direction

T

tangent point

Claims (21)

1. Casting and rolling installation (1) for producing metal strips (2), wherein the metal strip (2) runs through the casting and rolling installation (1) in a conveying direction (F), comprising:

   a casting machine (3) with a mould with a vertical outlet for producing a cast strip and a strip guide (4), which is downstream of the mould in conveying direction (F), for deflecting the cast strip from the vertical to the horizontal,

   a connecting system (5), which is downstream of the strip guide (4) in conveying direction (F) and which comprises at least one straightening driver (6) for drawing the cast strip out of the strip guide (4) and a separating device (9), particularly shears, as well as an oven (7) for heating the cast strip, and

   a rolling mill (8), which is downstream of the connecting system (5) in conveying direction (F), for rolling the cast strip to form a metal strip (2),

   characterised in that

   the strip guide (4) comprises a single roller segment or two roller segments, wherein the rollers thereof provided for strip guidance are free of a drive.
2. Casting and rolling installation according to claim 1, characterised in that in the case of presence of two roller segments in the strip guide (4) these are of substantially identical construction.
3. Casting and rolling installation according to claim 1 or 2, characterised in that the strip guide (4) is constructed to so bend the cast strip that it has a minimum radius of curvature of 2,100 millimetres.
4. Casting and rolling installation according to any one of claims 1 to 3, characterised in that the strip guide (4) has the shape of a clothoid at least in a section.
5. Casting and rolling installation according to any one of claims 1 to 4, characterised in that the mould is constructed as a curved mould.
6. Casting and rolling installation according to any one of claims 1 to 5, characterised in that the length of the mould is at most 1,100 millimetres, preferably between 900 millimetres and 1,000 millimetres.
7. Casting and rolling installation according to any one of claims 1 to 6, characterised in that the height of the strip guide (4) without mould has a maximum height of 3 metres.
8. Casting and rolling installation according to any one of claims 1 to 7, characterised in that the connecting system (5) comprises the straightening and driver unit (6) and the oven (7), wherein a separating device (9), particularly shears, is arranged between the straightening and driver unit (6) and the oven (7) and wherein the straightening and driver unit and the separating device are preferably constructionally configured as a constructional unit.
9. Casting and rolling installation according to any one of claims 1 to 8, characterised in that the connecting system (5) comprises a cold strip rocker (10) with integrated insulation.
10. Casting and rolling installation according to any one of claims 1 to 9, characterised in that the strip guide (4) ends in front of the tangent point (T).
11. Casting and rolling installation according to any one of claims 1 to 9, characterised in that the strip guide (4) ends in or behind the tangent point (T).
12. Casting and rolling installation according to any one of claims 1 to 11, characterised in that the straightening and driver unit (6) comprises driven rollers on the upper side and the lower side of the slat (2).
13. Casting and rolling installation according to any one of claims 1 to 12, characterised in that the oven (7) is shorter than 100 metres.
14. Casting and rolling installation according to any one of claims 1 to 13, characterised in that the oven (7) comprises at least one inductive heating element.
15. Casting and rolling installation according to claim 14, characterised in that at least one heating hood is arranged upstream or downstream of the oven (7) in conveying direction.
16. Method of operating a casting and rolling installation according to any one of claims 1 to 15,
    characterised in that
    the cast strip cast in the casting machine (3) is fed, without further heating in the oven (7), to the rolling mill (8) and rolled therein.
17. Method according to claim 16, characterised in that the cast strip, which has been cast, is so cooled in the strip guide that on reaching the straightening driver (6) it has been completely hardened through.
18. Method according to claim 15 or 16, characterised in that the cast strip, which has been cast, is so cooled through regulation of the cooling water quantity and/or the casting speed that it is completely hardened through 500 millimetres to 10 millimetres in front of the last roller of the strip guide in conveying direction (F).
19. Method according to any one of claims 15 to 18, characterised in that the oven entry temperature is greater than 1,050° C.
20. Method according to any one of claims 15 to 19, characterised in that the carbon steels are processed with lower and medium carbon contents.
21. Method according to any one of claims 15 to 20, characterised in that the cast strip exits the strip guide of the casting installation with a thickness between 40 millimetres and 60 millimetres, preferably 45 millimetres to 55 millimetres.

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