EP3197618B1 - Method for quickly converting a single-train continuous casting plant for slabs into a multi-train continuous casting plant for billets, and vice versa - Google Patents

Description

Field of engineering

The present invention relates to the technical field of continuous casting. Continuous casting today casts the majority of the world steel produced annually in continuously operated continuous casters into strands of varying cross-sections (e.g., slabs, billets, billets, profiles).

Both continuous casting machines for continuously casting molten steel into a strand with billet (engl. Billet) or slab (engl. Slab) cross-section are known.

On the one hand, the present invention relates to a method for the rapid conversion of a single-strand slab caster (ie, a continuous caster for continuous casting of liquid steel into a slab cross section) into a multi-strand billet continuous caster (ie, a continuous caster for continuous casting of liquid steel into multiple strands having billet cross section ).

On the other hand, however, the invention also relates to a method for the rapid conversion of a multi-strand billet continuous casting into a single-strand slab continuous casting.

State of the art

Both methods for converting a single-strand slab continuous casting into a multi-strand billet continuous casting and vice versa are basically known. In this case, a continuous casting of a type by a time-consuming conversion converted into a continuous casting plant of the other type. However, since the replacement of the mold (s), the oscillating unit (s) for the mold (s) and the strand guide takes a long time, the plant operator can not respond promptly to cyclical variations in the demand for slab or billet strings. Thus, on the one hand, the plant operator can not fully utilize his existing continuous casters or sell the strands, which are currently in less demand, with maximum profit, or, on the other hand, he can not cover a temporary demand. Both cases are unsatisfactory for the plant operator. Finally, the plant operator can not operate his continuous caster during the conversion, resulting in significant output losses (which are proportional to the conversion time).

From the publication

Liu HS et al: "Combined continuous caster for billets and slabs", Stahl and Eisen 121 (2001) No. 1, pages 61-69 is the conversion of a multi-strand billet plant in a single-strand slab plant and vice versa known. When converting into a billet plant among other things, the mold and the strand guide segment 1 are changed. The components mold, oscillation and the strand guide segment 1 were formed as a compact unit.

In the WO 2009/141210 A1 is a strand guide for a single-strand billet or bloom described. By the described solution, the first strand guide segment alone and a subsequent strand guide segment can be expanded together with the segment frame.

Summary of the invention

The object of the present invention is to provide a method for the rapid conversion of a single-strand slab continuous casting into a multi-strand billet continuous casting and to provide a method for rapidly converting a multi-strand billet continuous caster into a single-strand continuous slab caster.

This object is achieved by the method according to claim 1. Preferred embodiments are subject of the dependent claims.

• eine Kokille zum Vergießen von flüssigem Stahl in einen Brammenstrang und eine Oszilliereinheit zum Oszillieren der Kokille;
• eine Strangführung zum Stützen, Führen und Abkühlen des Brammenstrangs, wobei die Strangführung mehrere hydraulisch verstellbare Segmente aufweist, der Brammenstrang in den Segmenten durch Kühldüsen abgekühlt und gegebenenfalls in seiner Dicke reduziert wird, die Segmente mit einer Hinterkonstruktion mechanisch und mit je einer Hydraulik- und einer Wasserversorgung fluidtechnisch verbunden sind; aufweisend die Verfahrensschritte:
  1. i) Abkoppeln der Wasserversorgung von der Kokille und Abkoppeln der Hydraulikversorgung von der Oszilliereinheit;
  2. ii) Ausbau der Kokille und der Oszilliereinheit und Einbau eines gemeinsamen Stützrahmens für mehrere Knüppelstränge im Bereich des Maschinenkopfs der Stranggießanlage, wobei der gemeinsame Stützrahmen mit dem Festland der Stranggießanlage verbunden wird;
  3. iii) Einbau je einer Kokille zum Vergießen von flüssigem Stahl in einen Knüppelstrang und je einer Oszilliereinheit zum Oszillieren der Kokille pro Knüppelstrang, wobei mehrere Oszilliereinheiten mit dem gemeinsamen Stützrahmen verbunden werden;
  4. iv) Ankoppeln der Wasserversorgung an die Kokillen und Ankoppeln der Hydraulikversorgung an die Oszilliereinheiten;
  5. v) Abkoppeln der Wasserversorgung und Hydraulikversorgung von den Segmenten;
  6. vi) Lösen der Segmente von der Hinterkonstruktion der Stranggießanlage und Ausbau der Segmente aus der Stranggießanlage;
  7. vii) Verbinden von Rollenpaaren zum Führen mehrerer Knüppelstränge mit der Hinterkonstruktion, wobei die Knüppelstränge durch ein Rollenpaar beidseitig gestützt und durch Kühldüsen abgekühlt werden;
  8. viii) Ankoppeln der Kühldüsen der Rollenpaare an die Wasserversorgung;
  9. ix) Verbinden von zumindest einer Auszugseinheit zum Ausziehen mehrerer Knüppelstränge aus den Kokillen mit der Hinterkonstruktion;
  10. x) Ankoppeln der Auszugseinheit an die Hydraulikversorgung.

Specifically, the object is achieved by a method for converting a single-strand slab continuous casting into a multi-strand billet continuous casting, wherein the continuous slab caster comprises:

• a mold for casting liquid steel into a slab strand and an oscillating unit for oscillating the mold;
• a strand guide for supporting, guiding and cooling the slab strand, wherein the strand guide several hydraulically having adjustable segments, the slab strand is cooled in the segments by cooling nozzles and optionally reduced in thickness, the segments are mechanically connected to a rear structure and each with a hydraulic and a water supply; comprising the method steps:
  1. i) disconnecting the water supply from the mold and uncoupling the hydraulic supply from the oscillating unit;
  2. ii) removal of the mold and the oscillating unit and installation of a common support frame for a plurality of billet strands in the region of the machine head of the continuous casting plant, wherein the common support frame is connected to the mainland of the continuous casting plant;
  3. iii) installation of a mold for pouring liquid steel into a billet strand and a respective oscillating unit for oscillating the mold per billet strand, wherein a plurality of oscillating units are connected to the common support frame;
  4. iv) coupling the water supply to the dies and coupling the hydraulic supply to the oscillating units;
  5. v) disconnecting the water supply and hydraulic supply from the segments;
  6. vi) releasing the segments from the rear construction of the continuous casting plant and removing the segments from the continuous casting plant;
  7. vii) connecting pairs of rollers for guiding a plurality of billet strands to the rear structure, the billet strands being supported on both sides by a pair of rollers and cooled by cooling nozzles;
  8. viii) coupling the cooling nozzles of the pairs of rollers to the water supply;
  9. ix) connecting at least one pull-out unit for pulling out a plurality of billet strands from the molds with the rear construction;
  10. x) coupling the pull-out unit to the hydraulic supply.

By the conversion process according to the invention can both continuous slab caster with a straight or a curved Mold are quickly converted into a multi-strand billet continuous casting. For this purpose, first the machine head (ie the mold and the oscillating unit) of the slab continuous casting plant is rebuilt. After uncoupling the water supply from the mold and the hydraulic supply from the oscillating unit and removing the machine head of the continuous slab caster, a common support frame is installed and connected to the mainland of the continuous caster. In the common support frame, the oscillating units and the oscillating molds of the billet continuous casting are used. Due to the common support frame, the installation and removal of the machine head of the multi-strand billet continuous casting can be done very quickly.

In a particularly advantageous embodiment, the oscillating units and molds of the multi-strand billet continuous casting machine are not even solved by the common support frame, but installed and removed as a module.

After the coupling of the water supply to the molds and the coupling of the hydraulic supply to the oscillating units, the functioning of the machine head is restored. Subsequently, the segments of the continuous slab caster are released from the rear construction and removed, preferably extended over rails. To guide and support the billet strands pairs of rollers are connected to the existing rear construction. In order to cool the billet strands in the area of the roller pairs, the cooling nozzles of the roller pairs are connected to the existing water supply of the continuous casting machine. Finally, at least one extraction unit - e.g. in the form of a pair of rollers with driven rollers - connected to pull out a plurality of billet strands from the molds with the rear construction of the continuous casting and the pull-out unit connected to the hydraulic supply of the continuous casting.

Both in the water and hydraulic supplies, it is advantageous if the coupling and uncoupling of these compounds by coupling or uncoupling so-called quick couplings. As a result, the conversion time can be further reduced.

If a billet strand leaves the mold of the billet continuous casting machine bent with a radius of curvature, it is advantageous if the pairs of rolls in the strand guide of the billet continuous casting machine are connected to the rear construction such that the radius of curvature R _{101 of} the billet continuous casting machine is 0.9 * R ₁ ≤ R ₁₀₁ ≤ 1.1 * R ₁ , preferably R ₁₀₁ = R ₁ , where R _{1 is} the radius of curvature of the slab continuous casting machine. This measure makes the best use of the existing space in the continuous casting plant; In addition, this choice allows high casting speeds.

If a billet strand leaves the mold of the billet continuous casting machine in the vertical direction, it is advantageous if, after the mold of the billet continuous casting machine, a bending device for deflecting the vertical billet strand is arranged on an arcuate path with radius.

In order to make best use of the given space and to enable high casting speeds, it is advantageous if the pairs of rolls in the strand guide of the billet continuous casting machine are connected to the rear construction in such a way that 0.5 * R ₁ holds for the radius of curvature R _{101 of} the billet continuous casting machine ≤ R ₁₀₁ ≤ R ₁ , where R _{1 is} the radius of curvature of the slab continuous casting machine.

The object of the invention is also achieved by a method according to claim 7. Preferred embodiments are subject of the dependent claims.

• einen gemeinsamen Stützrahmen für mehrere Knüppelstränge, und pro Knüppelstrang je eine Kokille zum Vergießen von flüssigem Stahl in einen Knüppelstrang und je eine Oszilliereinheit zum Oszillieren der Kokille;
• eine Strangführung zum Stützen, Führen und Abkühlen der Knüppelstränge, wobei die Strangführung mehrere Rollenpaare zum Führen mehrerer Knüppelstränge und Kühldüsen zum Abkühlen der Knüppelstränge aufweist, wobei die Rollenpaare mit einer Hinterkonstruktion der Stranggießanlage verbunden sind;
• zumindest eine Auszugseinheit zum Ausziehen der Knüppelstränge aus den Kokillen;

aufweisend die Verfahrensschritte:

1. i) Abkoppeln der zumindest einen Auszugseinheit von der Hydraulikversorgung der Stranggießanlage, Lösen der Auszugseinheit von der Hinterkonstruktion und Entfernen der Auszugseinheit aus der Stranggießanlage;
2. ii) Abkoppeln der Kühldüsen der Rollenpaare von der Wasserversorgung;
3. iii) Lösen der Rollenpaare von der Hinterkonstruktion und Entfernen der Rollenpaare aus der Stranggießanlage;
4. iv) Einbau mehrerer hydraulisch verstellbarer Segmente zum Führen und Kühlen des Brammenstrangs in die Stranggießanlage, Verbinden der Segmente mit der Hinterkonstruktion, und Ankoppeln der Segmente an die Wasser- und die Hydraulikversorgung der Stranggießanlage, sodass der Brammenstrang in den Segmenten durch Kühldüsen abgekühlt und gegebenenfalls in seiner Dicke reduziert wird;
5. v) Abkoppeln der Wasserversorgung von den Kokillen und Abkoppeln der Hydraulikversorgung von der Oszilliereinheiten der Stranggießanlage;
6. vi) Ausbau des gemeinsamen Stützrahmens und der darin eingesetzten Kokillen und Oszilliereinheiten der Stranggießanlage und Einbau einer Kokille zum Vergießen von flüssigem Stahl in einen Brammenstrang und einer Oszilliereinheit zum Oszillieren der Kokille;
7. vii) Ankoppeln der Wasserversorgung an die Kokille und Ankoppeln der Hydraulikversorgung an die Oszilliereinheit der Stranggießanlage.

Specifically, the object is achieved by a method for converting a multi-strand billet continuous casting into a single-strand slab continuous casting, wherein the billet continuous casting machine comprises:

• a common support frame for a plurality of billet strands, and per billet strand per one mold for pouring liquid steel into a billet strand and a respective oscillating unit for oscillating the mold;
• a strand guide for supporting, guiding and cooling the billet strands, the strand guide having a plurality of pairs of rolls for guiding a plurality of billet strands and cooling nozzles for cooling the billet strands, the pairs of rolls being connected to a rear construction of the continuous casting plant;
• at least one extraction unit for removing the billet strands from the molds;

comprising the method steps:

1. i) decoupling the at least one extraction unit from the hydraulic supply of the continuous casting plant, releasing the extraction unit from the rear construction and removing the extraction unit from the continuous casting plant;
2. ii) decoupling the cooling nozzles of the roller pairs from the water supply;
3. iii) detaching the pairs of rollers from the rear construction and removing the pairs of rollers from the continuous casting machine;
4. iv) incorporating a plurality of hydraulically adjustable segments for guiding and cooling the slab strand into the continuous casting plant, connecting the segments to the rear structure, and coupling the segments to the water and hydraulic supply to the continuous casting plant so that the slab strand in the segments is cooled by cooling nozzles and optionally in its thickness is reduced;
5. v) decoupling the water supply from the molds and uncoupling the hydraulic supply from the oscillating units of the continuous casting plant;
6. vi) removal of the common support frame and the dies used therein and oscillating units of the continuous casting plant and installation of a mold for pouring liquid steel into a slab strand and an oscillating unit for oscillating the mold;
7. vii) coupling the water supply to the mold and coupling the hydraulic supply to the oscillating unit of the continuous caster.

Also in this method, the machine head of the multi-strand billet continuous casting can be quickly removed by the common support frame and the machine head of the slab continuous casting can be used quickly. In addition, of course, the existing rear construction and the existing water and hydraulic supplies can be reused.

If the slab strand leaves the mold of the slab continuous casting machine bent with a radius of curvature, it is advantageous if the segments in the strand guide of the slab continuous casting machine are connected to the rear structure such that the radius of curvature R _{1 of} the slab continuous casting machine is R ₁₀₁ / 1.1 ≤ R ₁ ≤ R ₁₀₁ / 0.9, preferably R ₁ = R ₁₀₁ , where R _{101 is} the radius of curvature of the billet continuous casting machine. This makes the best use of the existing space and enables a high casting speed.

If the slab strand leaves the mold of the slab continuous casting machine in the vertical direction, it is advantageous if, after the mold of the slab continuous casting machine, a bending device for deflecting the vertical slab strand is arranged on a circle arc path with radius.

In order to make best use of the given space and to enable high casting speeds, it is advantageous if the segments in the strand guide of the slab continuous casting machine are connected to the rear structure in such a way that for the radius of curvature R _{1 of} the slab continuous casting machine R ₁₀₁ ≦ R ₁ ≦ 2 * R ₁₀₁ , where R _{101 is} the radius of curvature of the billet continuous casting machine.

Brief description of the drawings

• Fig 1 eine Darstellung einer einsträngigen Brammen-Stranggießanlage
• Fig 2 eine Darstellung einer mehrsträngigen Knüppel-Stranggießanlage mit gerader Kokille
• Fig 3 eine Darstellung einer mehrsträngigen Knüppel-Stranggießanlage mit gebogenen Kokillen
• Fig 4 eine Darstellung eines Maschinenkopfs einer mehrsträngigen Knüppel-Stranggießanlage mit gebogenen Kokillen mit einem gemeinsamen Stützrahmen für drei Stränge

Further advantages and features of the present invention will become apparent from the following description of non-limiting embodiments, wherein the following figures show:

• Fig. 1 a representation of a single-strand continuous slab caster
• Fig. 2 a representation of a multi-strand billet continuous casting with straight mold
• Fig. 3 a representation of a multi-strand billet continuous casting with curved molds
• Fig. 4 a representation of a machine head of a multi-strand billet caster with curved molds with a common support frame for three strands

Description of the embodiments

In Fig. 1 is a single-strand slab continuous casting 1 with a straight mold 2, an oscillating unit 3, a strand guide 4, consisting of a bending device 5 for bending the vertical slab strand B on a circular arc with radius R and a total of 14 hydraulically adjustable segments 4a ... 4n shown , The segments 4a ... 4h serve to guide the slab strand B on the circular arc R or R ₁ and to cool the slab strand by cooling nozzles and possibly to reduce its thickness (for example by a soft core or liquid core reduction ). The following segments 4i ... 4n serve to guide the slab strand B horizontally and, if necessary, to further reduce the thickness of the slab strand B.

Above the actual continuous slab caster 1 certain parts, such as the mold 2, the oscillating unit 3, the bending device 5 and a segment 4a ... 4n have been shown in detail. The thick line between the slab caster 1 shown below and the detailed representation symbolizes the local relationship between the different representations.

As in Fig. 1 shown, the oscillating unit 3 is mechanically connected to the mainland 6 of the continuous casting and fluidly connected to a hydraulic supply; Furthermore, of course, the mold 2 is connected to the water supply. In addition, the segments 4 a ... 4 n are each mechanically detachably mechanically connected to the rear construction 7 and fluidly connected to a respective hydraulic and water supply. By means of the hydraulic supply, the slab strand B can be reduced in thickness by the at least four hydraulic cylinders of each segment. Through the supply of water, the slab strand B can be cooled by cooling nozzles.

By converting the single-strand slab continuous casting 1 of Fig. 1 in a multi-strand billet continuous caster 101 (see Fig. 2 or 3 ), the time-varying demand for either slabs or billets should be able to be satisfied in a timely manner and the conversion times are kept low. This is done by reusing as many parts as possible (eg the rear construction 7, the mainland 6 but also the existing water and hydraulic connections in the area of the machine head and in the area of the strand guide 4) in both types of installation. In order not to complicate the figures unnecessarily, was dispensed with the representation of the hydraulic and water supplies.

During conversion, the procedure is as follows:
First, the water supply from the mold 2 and the hydraulic supply from the oscillating unit 3 are disconnected. This is done by uncoupling quick couplings. Subsequently, the mold 2 and the oscillating unit 3 is removed and instead a common support frame 111 (please refer Fig. 4 ) for three billet strands K. In the common support frame 111, three oscillating units 103 and three molds 102 are used with billet format. The common support frame 111 is connected to the mainland 6. By coupling the water supply to the dies 102 (ideally only one water inlet and one drain for three molds, ie per support frame) and coupling the hydraulic supply to the oscillator units 103 (ideally again only one pressure line and one tank line for three oscillating units, ie per Supporting frame), the operability of the machine head of the billet continuous caster 101 is established. Subsequently, the segments 4a ... 4n are disconnected from the water and hydraulic supply, the segments released from the rear structure 7 and extended from the continuous casting over the rails shown; In addition, the bending device 5 is removed. Instead of the bending device 5 and the segments 4 of the slab continuous casting is in Fig. 2 In turn, a bending device 105 for a plurality of billet strands K and a plurality of pairs of rollers 104a ... 104i arranged for supporting and guiding the billet strands K. As in Fig. 2 2, the roller pairs 104a... 104i are connected to the existing rear construction 7 and the cooling nozzles of the roller pairs are connected to the existing water supply. In order to enable the extraction of the billet strands K from the molds 102, a plurality of pairs of rollers are formed as pull-out units, wherein the pairs of rollers are driven by a motor. For this purpose, these pairs of rollers are connected to a hydraulic connection. Out Fig. 2 shows that not all slab segments have been replaced by pairs of rolls. In general, this is not necessary since the billet strands are typically not reduced in thickness in the horizontal outlet region.

In contrast to the straight dies 102 of the billet continuous casting machine in Fig. 2 has the billet continuous casting the Fig. 3 curved molds 102 on. The bent molds 102 eliminate the need for a bending device for the billet strands K to install. This will further accelerate the conversion.

In Fig. 4 Finally, a machine head of a multi-strand billet continuous casting machine 101 with curved molds 102 is shown. Each bent mold 102 is oscillated by an oscillating unit 103, with three oscillating units 103 again supported on the common support frame 111. Specifically, the common support frame 111 is installed below the slab mold 2, which of course is removed prior to installation.

Since the conversion of a multi-strand billet continuous casting 101 in a single-strand slab continuous casting 1 essentially in the opposite direction to the conversion of a single-strand slab continuous casting 1 in a multi-strand billet continuous casting 101 of equip, this modification process is sufficiently disclosed for a person skilled in the art ,

When converting the multi-strand billet continuous caster 101 of Fig. 3 In a single-strand slab caster 1, the procedure is as follows:
First, the pull-out units 108 are disconnected from the hydraulic supply of the continuous casting machine 101, the pull-out units 108 are released from the rear construction 7 and removed from the continuous casting plant. Subsequently, the cooling nozzles of the roller pairs 104a ... 104g are decoupled from the water supply, the pairs of rollers released from the rear construction 7 and removed from the continuous casting. Furthermore, several hydraulically adjustable segments 4a ... 4n (see Fig. 1 ) for guiding and cooling the slab strand B introduced into the continuous casting and the segments 4a ... 4n connected to the rear construction 7. Finally, the segments 4a ... 4n are coupled to the water supply and the hydraulic supply of the continuous casting plant, so that the slab strand B in the segments 4a ... 4n can be cooled by cooling nozzles and optionally reduced in thickness. In connection to the conversion of the strand guide 4, the water supply to the dies 102 and the hydraulic supply is disconnected from the oscillating units 103 of the continuous casting. Then, the common support frame 111 and the molds 102 and oscillating units 103 inserted therein are removed, and instead, a mold 2 for casting liquid steel into a slab strand B and an oscillating unit 3 for oscillating the mold 2 are installed. By coupling the water supply to the mold 2 and the coupling of the hydraulic supply to the oscillating unit 3, the functionality of the machine head is restored.

It is clear to a person skilled in the art that it is not necessary either in the conversion process according to claim 1 or in the conversion process according to claim 7, the process steps exactly in the order given, e.g. i to x in claim 1 and i to vii in claim 7, respectively. For example, the steps v to x in claim 1 are also performed before the steps i to iv. The same applies to claim 7.

Within the scope of the invention is also the conversion of a multi-strand (eg two-strand) slab continuous casting into several (eg turn two) multi-strand billet continuous casting and vice versa fall. In this case, the process steps are performed multiple times, ie once each slab strand.

Although the invention has been further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art within the scope of the appended claims.

LIST OF REFERENCE NUMBERS

1

Single-strand slab caster

2

Mold for slab caster

3

Oscillating unit for the continuous slab caster

4

Strand guide for the continuous slab caster

4a ... 4n

Segment of the strand guide

5

bender

6

Mainland

7

behind construction

101

multi-strand billet continuous caster

102

Mold for the billet continuous caster

103

Oscillating unit for the billet continuous casting plant

104

Strand guide for the billet continuous casting plant

104a ... 104i

roller pair

105

Bending device for the billet continuous casting plant

108

pull-out unit

111

common support frame

B

continuous slab

K

stick strand

R, R ₁ , R ₁₀₁

radius of curvature

Claims (12)

1. Method for converting a single-strand continuous casting plant (1) for slabs into a multi-strand continuous casting plant (101) for billets, wherein the continuous casting plant (1) for slabs comprises

   - a mould (2) for casting liquid steel into a slab strand (B) and an oscillating unit (3) for oscillating the mould (2);

   - a strand guide (4) for supporting, guiding and cooling the slab strand (B), wherein the strand guide (4) has a plurality of hydraulically adjustable segments (4a...4n) the slab strand (B) is cooled in the segments (4a...4n) by cooling nozzles and, where appropriate, reduced in its thickness, and the segments (4a...4n) are mechanically connected to a rear construction (7) and fluidically connected to in each case a hydraulic supply and a water supply;

   comprising the following method steps:

   i) decoupling the water supply from the mould (2) and decoupling the hydraulic supply from the oscillating unit (3) of the continuous casting plant;

   ii) removing the mould (2) and the oscillating unit (3) and installing a common support frame (111) for a plurality of billet strands (K) in the region of the machine head of the continuous casting plant, wherein the common support frame (111) is connected to the main body (6) of the continuous casting plant;

   iii) installing in each case one mould (102) for casting liquid steel into a billet strand (K) and in each case one oscillating unit (103) for oscillating the mould (102) per billet strand (K), wherein a plurality of oscillating units (103) are connected to the common support frame (111);

   iv) coupling the water supply to the moulds (2) and coupling the hydraulic supply to the oscillating units (3) ;

   v) decoupling the water supply and hydraulic supply from the segments (4a...4n);

   vi) releasing the segments (4a...4n) from the rear construction (7) of the continuous casting plant and removing the segments (4a...4n) from the continuous casting plant;

   vii) connecting roller pairs (104a...104i) for guiding a plurality of billet strands (K) to the rear construction (7), wherein the billet strands (K) are supported on both sides by a roller pair (104a...104i) and cooled by cooling nozzles;

   viii) coupling the cooling nozzles of the roller pairs (104a...104i) to the water supply;

   ix) connecting at least one extraction unit (108) for extracting a plurality of billet strands (K) from the moulds (102) to the rear construction (7);

   x) coupling the extraction unit (108) to the hydraulic supply.
2. Method according to Claim 1, characterized in that a billet strand (K) leaves the mould (102) of the continuous casting machine (101) for billets in a curved manner with a radius of curvature (R, R₁₀₁).
3. Method according to Claim 2, characterized in that the roller pairs (104a...104i) in the strand guide (104) of the continuous casting machine (101) for billets are connected to the rear construction (7) in such a way that the following holds for the radius of curvature R₁₀₁ of the continuous casting machine (101) for billets: 0.9*R₁ ≤ R₁₀₁ ≤ 1.1 *R₁, preferably R₁₀₁ = R₁, where R₁ is the radius of curvature of the continuous casting machine (1) for slabs.
4. Method according to Claim 1, characterized in that a billet strand (K) leaves the mould (102) of the continuous casting machine (101) for billets in a rectilinear manner in vertical direction.
5. Method according to Claim 4, characterized in that a bending device (105) for deflecting the vertical billet strand (K) onto a circular arc with radius (R₁₀₁) is arranged downstream of the mould (102) of the continuous casting machine (101) for billets.
6. Method according to either of Claims 4 and 5, characterized in that the roller pairs (104a...104i) in the strand guide (104) of the continuous casting machine (101) for billets are connected to the rear construction (7) in such a way that the following holds for the radius of curvature R₁₀₁ of the continuous casting machine (101) for billets: 0.5*R₁ ≤ R₁₀₁ ≤ R₁, where R₁ is the radius of curvature of the continuous casting machine (1) for slabs.
7. Method for converting a multi-strand continuous casting plant (101) for billets into a single-strand continuous casting plant (1) for slabs, wherein the continuous casting plant (101) for billets comprises:

   - a common support frame (111) for a plurality of billet strands (K), and, per billet strand (K), in each case one mould (102) for casting liquid steel into a billet strand (K) and in each case one oscillating unit (103) for oscillating the mould (102);

   - a strand guide (104) for supporting, guiding and cooling the billet strands (K), wherein the strand guide (104) has a plurality of roller pairs (104a...104i) for guiding a plurality of billet strands (K) and cooling nozzles for cooling the billet strands (K), wherein the roller pairs (104a...104i) are connected to a rear construction (7) of the continuous casting plant;

   - at least one extraction unit (108) for extracting the billet strands (K) from the moulds (102);

   comprising the following method steps:

   i) decoupling the at least one extraction unit (108) from the hydraulic supply of the continuous casting plant, releasing the extraction unit (108) from the rear construction (7) and removing the extraction unit (108) from the continuous casting plant;

   ii) decoupling the cooling nozzles of the roller pairs (104a...104i) from the water supply;

   iii) releasing the roller pairs (104a...104i) from the rear construction (7) and removing the roller pairs (104a...104i) from the continuous casting plant;

   iv) installing a plurality of hydraulically adjustable segments (4a...4n) for guiding and cooling the slab strand (B) into the continuous casting plant, connecting the segments (4a...4n) to the rear construction (7), and coupling the segments (4a...4n) to the water supply and the hydraulic supply of the continuous casting plant, with the result that the slab strand (B) is cooled in the segments (4a...4n) by cooling nozzles and, where appropriate, reduced in its thickness;

   v) decoupling the water supply from the moulds (102) and decoupling the hydraulic supply from the oscillating units (103) of the continuous casting plant;

   vi) removing the common support frame (111) and the moulds (102) and oscillating units (103) of the continuous casting plant that are inserted therein and installing a mould (2) for casting liquid steel into a slab strand (B) and an oscillating unit (3) for oscillating the mould (2);

   vii) coupling the water supply to the mould (2) and coupling the hydraulic supply to the oscillating unit (3) of the continuous casting plant
8. Method according to Claim 7, characterized in that the slab strand (B) leaves the mould (2) of the continuous casting machine (1) for slabs in a curved manner with a radius of curvature (R, R₁).
9. Method according to Claim 8, characterized in that the segments (4a...4n) in the strand guide (4) of the continuous casting machine (1) for slabs are connected to the rear construction (7) in such a way that the following holds for the radius of curvature R₁ of the continuous casting machine (1) for slabs: R₁₀₁/1.1 ≤ R₁ ≤ R₁₀₁/0.9, preferably R₁ = R₁₀₁, where R₁₀₁ is the radius of curvature of the continuous casting machine (101) for billets.
10. Method according to Claim 7, characterized in that a slab strand (B) leaves the mould (2) of the continuous casting machine (1) for slabs in a rectilinear manner in the vertical direction.
11. Method according to Claim 10, characterized in that a bending device (5) for deflecting the vertical slab strand (B) onto a circular arc path with radius (R₁) is arranged downstream of the mould (2) of the continuous casting machine (1) for slabs.
12. Method according to either of Claims 10 and 11, characterized in that the segments (4a...4n) in the strand guide (4) of the continuous casting machine (1) for slabs are connected to the rear construction (7) in such a way that the following holds for the radius of curvature R₁ of the continuous casting machine (1) for slabs: R₁₀₁ ≤ R₁ ≤ 2*R₁₀₁, where R₁₀₁ is the radius of curvature of the continuous casting machine (101) for billets.

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