EP3535076A1

EP3535076A1 - Combined casting-rolling installation and method for the continuous production of a hot-rolled finished strip

Info

Publication number: EP3535076A1
Application number: EP17787436.9A
Authority: EP
Inventors: Roman Winkler
Original assignee: Primetals Technologies Austria GmbH
Current assignee: Primetals Technologies Austria GmbH
Priority date: 2016-11-03
Filing date: 2017-10-24
Publication date: 2019-09-11
Anticipated expiration: 2037-10-24
Also published as: AT519277A1; CN109922904A; WO2018082966A1; RU2747341C2; RU2019113143A; EP3535076B1; RU2019113143A3; CN109922904B

Abstract

The invention relates to the technical field of combined casting-rolling installations. The aim of the invention is to provide a compact combined casting-rolling installation and a method for the continuous production of a hot-rolled finished strip (15) in the combined casting-rolling installation, whereby a high-quality finished strip (15) having different steel qualities can be produced at low cost. This aim is achieved by the combined casting-rolling installation according to claim 1 and a method for the continuous production of a hot-rolled finished strip (15) of steel according to claim 9.

Description

description

G ESS-WALZ VERBU N DAN LAG E AND METHOD FOR THE ENDLESS

MANUFACTURE OF A HOT-ROLLED FABRIC OF THE TECHNICAL FIELD

The present invention relates to the technical field of cast-rolled composite plants, which are plants in a casting plant (typically a continuous casting plant for

continuous production of a steel strand with

Slab format, e.g. Thin or medium slabs) directly and inline with a hot rolling line for producing a hot rolled strip is connected. The hot rolled strip is cooled after the hot rolling line in a cooling section and then discharged, e.g. by winding up the

Bandes to coils (engl., Coils). In the literature these installations are e.g. also known as TSCR (Thin Slab Casting and Rolling) or Arvedi ESP equipment. In particular, the invention relates to endlessly operated cast-rolled composite plants in which the casting plant as a

Thin slab continuous casting machine is formed (English TSER Thin S_lab Endless Rolling). In the process, the continuously produced in the continuous slab caster is endless

Thin slab strand direct, inline and uncut

Hot rolling fed and rolled there to an endless belt. After the hot rolling line, the strip is again cooled in a cooling section, then cut for the first time to a specific length or weight and wound into coils.

State of the art

Although an Arvedi ESP plant is already much more compact than a CSP or a QSP plant with a tunnel kiln, and the associated operating costs and CO ₂ emissions per ton of hot rolled strip has been greatly reduced, there is a need for even more compact cast-and-roll composite plants Production of an annual production amount of hot-rolled strip in the range of 1 million tons.

The solutions currently on the market, such as a continuous casting line with a downstream broadband line, an Arvedi ESP, Danieli QSP-DUE or SMS CSP / CEM system, are not compact enough for these low volumes and / or due to much higher annual production volumes of about 2.5 million tonnes and the high capital investment CAPEX with an annual production volume of about 1 million tons not economically operable. Thus, especially for small steelworks, there is a need for a compact cast-and-roll composite plant which is inexpensive to purchase and operate, yet still has high quality hot strip

can produce different grades of steel.

Two-roll strip casters with a downstream hot rolling mill are also known from the prior art. Although a two-roll strip caster is very compact and produces a ribbon immediately, it has

Technology to date can not enforce because

especially medium to higher alloyed steel grades can not be reliably produced. From WO 89/11363 AI is a concept for a casting-rolling

Verbundanlage known in which a produced in a continuous casting thin slab strand uncut in one

Pre-rolling mill rough-rolled, then reheated, descaled, finish-rolled in a finishing train, cooled and wound up. Investigations by the applicant have shown that due to the fact that in this concept the solidification of the thin slab strand takes place in the casting arc of the continuous casting machine, a relatively low

Stichting temperature during rough rolling results, with the result that the energy required for the conversion of Gussin a rolling structure is much higher than necessary.

In addition, the so-called ISP concept leaves many questions unanswered, eg how to separate the cold strand when casting the Continuous casting takes place according to Figure 1, as is responding to problems in a rear part of the system, etc. Thus, the concept described is only limited industrial use. From AT 512399 Bl and DE 102008003222 AI are cast-rolling compound plants with three Vorwalzengerüsten and five

Prefabricated rolling stands known. EP 2441539 A1 shows a cast-rolled composite plant with four roughing stands and five finish rolling stands. The plants in the three aforementioned publications are for annual production quantities of about 2.5

Million tons and more laid out. DE 19518144 AI shows a so-called. Very small hot rolling mill with three Vorwalzgerüsten and five Fertigwalzgerüsten. By combining a

Induction heating and a leveling furnace between the roughing mill and the finishing mill builds the plant but relatively long. Compared to the prior art, the overall length of the cast-rolled composite system is to be further reduced and the

Energy input for the production of finished strip can be further reduced.

Summary of the invention

The object of the invention is to provide a compact casting-rolling compound of the type mentioned and a

Method for endless production of a hot-rolled

To specify finished strips on the cast-rolled composite plant, with which high-quality finished strip of different steel grades (low and medium carbon, but also HSLA, API grades, etc.) can be produced inexpensively.

This object is achieved by the cast-rolling composite system according to claim 1. Advantageous embodiments are

Subject of the dependent claims.

The straight die, preferably a funnel mold in combination with the subsequent vertical section of the strand guide, ensures that any non-metallic inclusions in the molten steel at the meniscus accumulate and be bound by the casting powder. This will increase the metallurgical quality of the thin slab strand

improved. By the relatively thick and wide

Thin slab strand at the exit of the mold on the one hand, a high mass flow through the plant achieved and on the other hand by the thickness reduction (for example, a so-called. Liquid Core

Reduction) in the strand leadership yet already in the

Continuous casting a relatively thin thin slab strand produced. At least

- the secondary cooling in the strand guide, and

the casting speed v _c ,

and preferably one parameter from the list

- the primary cooling in the mold,

the thickness reduction in the strand guide,

be by a control or regulating device of

Continuous casting set so that the thin slab strand solidifies only in a horizontal section of the strand guide, i. that the marsh end of the

Thin slab strand in the horizontal section of the

Strand guide is located.

The controlled by the control or regulating device or controlled operation of the continuous casting, so that the

Swamp tip of the thin slab strand, even under changing operating conditions in the continuous casting plant or the cast-rolled composite plant always within the horizontal

Section of the strand guide comes to lie is the

Specialist e.g. from WO 01/03867 AI known. The

this disclosure is hereby incorporated by reference into this application.

This procedure ensures that the thin slab strand takes along as much casting heat as possible, as well as the forming work in the roughing and finishing mill and the necessary

Reheating energy are as low as possible. In the

Vorwalzstraße the thin slab strand is rolled from a thickness of 50 to 70 mm through two roughing stands to a pre-strip with a thickness of 10 to 30 mm. The pendulum scissors, which, for example, serves to cut off a cold strand, as well as the discharge device for removing the cold strand are passed uncut in continuous operation. To that

Vorband not cool too much, preferably a thermal insulation is attached to the top and bottom of the discharge. Subsequently, the pre-strip is heated by an induction furnace to a temperature of 1050 to 1250 ° C and descaled before the finish rolling the top and bottom of the Vorbands by a descaling. In the finishing mill, the opening band is replaced by three

Rolling mills rolled to a finished strip with a thickness of 1.6 to 12 mm, then in the cooling section on

Cooling temperature cooled, first cut by the scissors and tied in the winding device

wound up.

As already stated above, the straight mold is preferably designed as a funnel mold. This allows the

Area around the meniscus a much larger

Have cross-sectional area than the pouring end of the mold, so that the casting powder can absorb more inclusions.

A favorable compromise between the height and the

Purity of the thin slab strand is the

arcuate portion of the strand guide with a

Arc radius R from 3 to 7 m, preferably from 4 to 6 m, more preferably from 4.5 to 5.5 m form.

In order to prevent overcooling of the edge regions of the thin slab strand, it is advantageous if the secondary cooling at several positions within the strand guide at least two in a width direction of the

Thin slab strand has movable spray nozzles. As a result, different widths of the thin slab strand are not undercooled. Also in the area between the end of the horizontal portion of the strand guide and the roughing mill, it is advantageous if heat insulation panels prevent the cooling of the thin slab strand.

In order to keep the temperature drop by descaling as low as possible, it is advantageous if the

Descaling device on the top and bottom each arranged a plurality in the width direction

Rotary teaser includes.

For the compactness of the cast-rolling composite plant, it is favorable if the horizontal distance between two

Prefabricated rolling stands between 3 and 6 m, in particular between 4 and 5 m, and / or the length of the cooling section between 20 to 60 m, preferably 20 to 40 m, is. Due to the small stand spacing of the finishing mills, a strong cooling of the strip is also avoided. The object of the invention is also by a

Method for endless production of a hot-rolled

Finished strip made of steel according to claim 9. Advantageous embodiments sing the subject of the dependent claims. During operation of the cast-rolled composite installation according to the invention, the casting speed of the thin-slab strand v _{c is} > 4 m / min, preferably v _c > 5 m / min, particularly preferably v _c > 6 m / min. This ensures high productivity and makes it easier to keep the sump tip in the horizontal area of the strand guide. In addition, the energy for heating the Vorbands is reduced in the induction furnace. The

Control or regulating device of the continuous casting at least

the secondary cooling in the strand guide, and - the casting speed v _c

and preferably another parameter from the list

the primary cooling in the mold,

the thickness reduction in the strand guide such that the thin slab strand only in one

horizontal section of the strand guide solidified. The reduced thickness thin slab strand is descaled, i. without being descaled in a descaling device, fed to the roughing train and rolled there to a pre-strip.

In the control or regulation of continuous casting, it is advantageous if the control or regulating device using a mathematical model

an actual position of a sump tip along the

Transport path of the thin slab strand in the strand guide and

- An actual temperature profile along the transport path of the thin slab strand in the strand guide and in normal planes to it

continuously calculated and the thin slab strand taking into account a target temperature profile and a desired position of the sump tip by the secondary cooling

is cooled continuously, regulated. This will keep the sump tip in the horizontal area of the

Strand guidance facilitates and overcooling the

Strangkantenbereiche prevented. In addition, by comparing the target and the actual temperature profile too much cooling of the edge regions of the

Thin slab strand can be avoided.

When reducing the thickness, it is advantageous if a soft reduction in an area with still liquid or

Partly liquid core of the thin slab strand by a

Adjustment device for strand guide rollers (for example, by strand guide segments) is applied. This reduces deformation work and also increases metallurgical quality.

A particularly simple and energy-efficient adjustment of the final rolling temperature is achieved by measuring the actual temperature Tl _{Ist of} the strip after the third roll pass in the Finish rolling mill and prior to cooling in the cooling section and the temperature-controlled driving a plurality of inductors of the induction furnace, so that the actual temperature Tl _Is _soll corresponds to a desired temperature Tl possible.

The accuracy is further increased if, alternatively, the actual temperature Tl * _{Is of} the strip is measured after the second pass and before the third pass in the finishing train and several inductors of the induction furnace

controlled temperature-controlled, so that the actual temperature Tl * _Ist a target temperature Tl * _So n as possible corresponds.

For setting the microstructural properties of the finished strip, it is advantageous if the actual temperature T2 _is the endless finished belt after cooling in the cooling section is measured and a plurality of cooling nozzles of the cooling section are controlled temperature, so that the actual temperature T2 _Ist a target temperature T2 _As many as possible.

In the production of relatively thin finished strip, it is advantageous if the endless finished strip leaves the finishing train with a first thickness dl after starting up the cast-rolled composite plant, then the thickness of the finished strip in continuous uninterrupted operation gradually reduced to a second thickness d2 <dl is, and before the downcast of the cast-rolling composite plant, the thickness of the finished strip in the

Continuous continuous operation is gradually increased to a third thickness d3> d2.

It is favorable if the first thickness d1 is between 3 and 12 mm, the second thickness d2 is between 1.6 and 12 mm and the third thickness d3 is between 3 and 12 mm. Since a high hydrogen content in the molten steel the

Reduced heat dissipation in the mold, it is advantageous if the hydrogen content of the steel before continuous casting, for example by a vacuum treatment, is reduced to -S 3 ppm. In addition, this measure has a favorable effect on the

Continuous casting of delicate steel grades, e.g. thermoformable steels. Brief description of the drawings

Further advantages and features of the present invention will become apparent from the description of non-limiting embodiments. The following schematic

Figures shown show:

1 is a perspective view of a casting-rolling composite plant Fig 2 is a representation of the continuous casting of Fig. 1

3 shows an illustration of the different sections of the strand guide of the continuous casting installation, FIG. 4 shows a representation of a plurality of width-adjustable sections

Spray nozzles in the strand guide of the continuous casting plant

5 shows an illustration of a temperature profile during the production according to the invention of a thin, hot-rolled finished strip in a cast-rolled composite plant

6 shows an illustration of a thickness profile of a finished strip in the application of the method according to the invention in a cast-rolled composite plant

Description of the embodiments

1 shows schematically a cast-rolled composite plant according to the invention for producing a hot-rolled finished strip 15 made of steel. The pretreated by a vacuum treatment liquid steel with a hydrogen content -S 1 ppm is transported in pans to the ladle turret (in the figure far left) of the continuous casting 1 and there over poured a Gießverteiler in the formed as a funnel mold mold 2. In the mold 2 is formed

Thin slab strand 3 with a thin strand shell having a thickness of 60 to 75 mm and a width of 900 to 1700 mm. The partially solidified thin slab strand 3 is continuously drawn from the mold 2 and in the

subsequent strand guide 4 supported, guided and further cooled by a secondary cooling. The strand guide 4 has a vertical portion 4a, an arcuate portion 4b having a plurality of thickness reduction devices 6 formed as strand guide segments, and a horizontal portion 4c (see FIG. 3). By the

Thickness reduction devices 6 (see FIG. 2) become the

Thin slab strand 3 to a thickness of 50 to 70 mm

reduced, wherein the thin slab strand in the reduction of a liquid core 5 (a so-called. Liquid Core Reduction) or partially liquid core has. To the mechanical

Verforumungsarbeit in the subsequent rolling steps in the roughing 8 or finishing mill 14 to keep as low as possible and keep the casting heat in the thin slab 3, the primary cooling in the mold 2, the secondary cooling in the strand guide 4 and the casting speed v _c by a control and / or control device 20 of the

Continuous casting 1 set such that the

Thin slab strand 3 solidified only in the horizontal section 4c of the strand guide 4. According to the invention, the continuous casting plant 1 is operated at a casting speed v _c of 5.5 m / min (see also FIG. 3 for the indication of

Casting speed). The reduced thickness, solidified, not descaled and uncut thin slab strand 3 is rolled immediately after the continuous casting in two roughing stands Rl, R2 of the roughing mill 8 to a pre-strip 9 with a thickness of 10 to 30 mm. In the continuous operation according to the invention of the cast-rolled composite plant according to the invention that happens

Vorband 9 a pendulum scissors 10 for cutting a

Kaltstrangs after casting the continuous casting 1 and a discharge 11 uncut. To cool the To reduce Vorbands 9, the discharge device 11 is lined with Isolierpanelen.

The controlled by the control or regulating device 20 or controlled operation of the continuous casting, so that the sump tip of the thin slab strand 3 within the

horizontal portion 4c of the strand guide 4 comes to rest, e.g. from WO 01/03867 AI known. The

this disclosure is hereby incorporated by reference into this application.

If a problem in a downstream part of the discharge 11 occur, the endless operation is left and the continuous casting of the 1 or the

Vorwalzstraße 8 nachkommende material cut by the pendulum shear 10 to short Vorbandabschnitten and discharged by the Ausfördereinrichtung 11 from the roller table between the pre-8 and the finishing train 14. This is after the first cut of the pendulum scissors 10 behind the

Pendulum scissors raised 10 lying Vorband so that

reliable collisions between the coming of the roughing mill 8 material and lying behind the pendulum scissors 10 pre-strip 9 can be avoided. If necessary, the temperature of the Vorbands 9 in an induction furnace 12 to a temperature of 1050 to 1250 ° C, preferably 1150 to 1200 ° C, increased. Here, the inductors of the induction furnace 12 are temperature controlled

controlled so that the measured actual temperature before the last rolling pass F3 in the finishing train 14 corresponds to a predetermined target temperature as possible. By this measure is also at a low

Casting speed v _c reliably reaches a preset Endwalztemperatur.

Before the finish rolling, the top and the bottom of the heated Vorbands 9 freed by a descaling device 13 of scale. In the three-stand finishing mill 14 the descaled Vorband 9 is rolled to a finished strip 15 having a thickness of 1.6 to 12 mm, then cooled by a cooling section 16 to winding temperature, cut by the scissors 17 and wound into the winding devices 18 into coils.

FIG. 2 shows further details of the continuous casting plant 1

shown. 3 shows the vertical section 4a, the arcuate section 4b and the horizontal section 4c of the strand guide 4 of the continuous casting plant 1 closer. Due to the straight mold 2 and the vertical portion 4a, inclusions in the molten steel accumulate on the meniscus, are absorbed by the casting powder and in the form of molten slag to

Strand lubrication used. The radius R of the arcuate strand guide 4b is shown in FIG. 3 and is approximately 5 m in the continuous casting plant according to the invention. Of the

Thin slab strand 3 immediately (i.e., without descaling) enters the first roughing stand R1 of the roughing train 8 after the horizontal section 4c. Furthermore, the figure shows how a thin slab strand 3 with a liquid core 5 leaves the mold 2 and in the strand guide 4th

is reduced in thickness. The reduced thickness thin slab strand 3 is driven by one as a pair of

Strand guide rollers trained extractor 7 pulled out of the mold 2. To the swamp tip of the

Thin slab strand 3 in the horizontal section 4c of

Strand guide 4 to hold, the casting speed v _c , optionally, the thickness reduction by means of

Thickness reduction device 6, set by the control and / or regulating device 20 controlled or regulated.

4, a width-adjustable secondary cooling in the strand guide 4 is shown. In both narrow 3 and wide thin slab strands 3 ^Λ , overcooling of the edge portions of the strands is prevented by the outer two spray nozzles 19 both in the width direction and normal to Extruded surface are designed to be displaceable. The

Spray nozzles 19 are about Spritdüsenhalter 21 with a

Linear drive 22 is connected, which shifts the spray nozzles 19 in the axial direction of the linear drive 22. The central spray nozzle 19 can either fixed or as

represented, also be designed to be displaceable.

In Fig 5, the temperature profile in ° C at the

production of a hot-rolled finished strip according to the invention in the cast rolled strip mill according to the invention. The core temperature is dashed each, the

Surface temperature punctured and the

Average temperature shown in solid. A

Grade DD11 molten steel is subjected to a vacuum treatment prior to continuous casting, reducing the hydrogen content in the liquid steel to -S 1 ppm. In the

Funnel mold 2 of the continuous casting 1 is a

formed partially solidified thin slab strand 3 with a thickness of 70 mm and a width of 1300 mm and reshaped by a liquid core reduction to a solidified thin slab strand 3 with a thickness of 60 mm. The solidified thin slab strand 3 leaves the horizontal section 4 _{c of} the continuous caster 1 with a casting speed of v _c = 6 m / min and is without descaling a zweigerüstigen

Pre-rolling 8 fed and there through the two

Vorgerüste Rl and R2 reduced to a pre-strip 9 with a thickness of 10 mm. Due to the relatively large distance between the exit region of the second roughing stand R2 and the

Input range of the induction furnace 12 cools the pre-strip 9 to a temperature of about 860 ° C. By the

Induction furnace 12 and IH is the pre-strip 9 on a

Temperature of about 1115 ° C brought. Subsequently, the pre-strip 9 is descaled by the descaling device 13 or DES, whereby the surface temperature drops to about 950 ° C; The core temperature is approx. 1020 ° C. The descaled Vorband 9 is then in the three

Finish rolling mills Fl, F2 and F3 of the finishing train 14 rolled to a finished strip 15 having a thickness of 1.6 mm, then cooled in the cooling section 16, cut and wound into coils.

In Fig. 6, the thickness profile of a relatively thin

Finished 15 specified during the preparation of the invention. After starting up the cast roll mill, initially a finished strip 15 having a thickness of d1 = 4 mm is produced. The endlessly produced finished strip 15 is cut off after cooling in a cooling section 16 by a pair of scissors 17 and wound up by one of the winding devices 18 to form a first bundle. Subsequently, the thickness of the finished strip of dl = 4 mm is gradually reduced to d2 = 1.6 mm. This is done by at least one of the following measures:

a) the thin slab strand 3 is stronger in the continuous casting 1 by thickness reduction devices

reduced thickness, so that he leaves the continuous casting 1 thinner,

b) the thin slab strand 3 is reduced in thickness by the roughing mill 8, so that the pre-strip 9 the

Pre-rolling mill 8 thinner leaves,

c) the pre-strip 9 is thicker in thickness in the finishing train 14, so that the finished strip 15 the

Finish rolling mill 14 thinner leaves.

If e.g. only measure a is used, it should be assumed that the reduction rates in the

Pre-rolling line 8 and the finishing train 14 are kept constant. This also applies mutatis mutandis to measures b and c. Of course, it is also possible that several measures are applied during the production of a single federal.

According to FIG. 6, the finished strip after 5 bundles has a thickness of d2 = 1.6 mm. This thickness is then for about 70

Maintain ties and then the thickness of d2 = 1.6 mm gradually increased to d3 = 3.2 mm. These measures are advantageous because on the one hand particularly thin finished strip (here with a thickness of 1.6 mm) not immediately after

But the plant has a longer time to "settle in." Only then is particularly thin finished strip produced.Generally, the operator of the cast-rolling composite system is interested in the largest possible share of thin hot strip Before lowering the cast-and-roll composite plant, the thickness of the finished strip 15 is again increased, thereby reducing the risk of production losses in the last section of a production campaign one of the above-mentioned measures mutatis mutandis in the opposite direction (less strong instead of stronger and thicker instead of thinner) for use. All measures are in continuous uninterrupted operation of the plant

applied, whereby disturbances, such as by threading the Vorbands 9 in the finishing train 14, be avoided. This alone is the stability of the

Production process greatly increased.

The thickness values and fret numbers given in FIG. 6 are not restrictive, but merely give an example.

Although the invention in detail by the preferred

While embodiments have been further illustrated and described, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the present invention

To leave invention.

LIST OF REFERENCE NUMBERS

1 continuous casting plant

2 mold

3, 3 ^Λ thin slab strand

4 strand guide

4a vertical section of the strand guide

4b arcuate section of the strand guide

4c horizontal section of the strand guide

5 liquid core

6 Thickness reduction device

7 Extraction device

8 roughing line

9 opening act

10 pendulum scissors

11 discharge device

12, IH induction furnace

13, DES descaling device

14 finishing train

15 finished tape

16 cooling section

17 scissors

18 winding device

19 spray nozzle

20 control and / or regulating device

21, 21 ^Λ Spray nozzle holder

22 linear drive dl first thickness

d2 second thickness

d3 third thickness

F1, F2, F3 finish rolling stands

R radius

R1, R2 roughing stands

v _c casting speed

Claims

claims

1. Cast-rolling composite plant for producing a

Hot-rolled finished strip (15) of steel, comprising

- A continuous casting plant (1), the

- A straight mold (2) for continuous

Manufacturing a thin slab strand (3) having a liquid core (5), a thickness of 60 to 75 mm and a width of 900 to 1700 mm at the exit from the mold (2);

- A strand guide (4) for supporting and guiding the thin slab strand (3) with a secondary cooling for cooling the thin slab strand (3) and a

Thickness reduction device (6) for reducing the thickness of the thin slab strand (3), wherein the strand guide (4) has a vertical section (4a) below the mold, subsequently an arcuate section (4b) and subsequently a horizontal section (4c), and the thin slab strand (3 ) has a thickness of 50 to 70 mm after the thickness reduction;

- A control or regulating device (20) for

Adjustment of secondary cooling and the

Casting speed v _c , so that the thin slab strand (3) solidifies only in the horizontal section (4c) of the strand guide (4);

includes;

- A roughing mill (8) for roughing the thickness-reduced thin slab strand (3), wherein the roughing mill (8) exactly two Vorwalzgerüste (Rl, R2) and the Vorwalzen a Vorband (9) is produced with a thickness of 10 to 30 mm;

- A pendulum scissors (10) for cutting a dummy strand;

- A discharge device (11) for discharging the

Cold strand, wherein the discharge device (11) has a thermal insulation for the reduction of heat losses; - An induction furnace (12) for heating the Vorbands (9) to a temperature of 1050 to 1250 ° C, preferably 1150 to 1200 ° C;

- a descaling device (13) for descaling a top and a bottom of the heated pre-strip (9);

a finishing train (14) for finish rolling the

descaled sliver (9), wherein the finishing train (14) has exactly three finish rolling stands (Fl, F2, F3) and by the finish rolling a finished strip (15) is produced with a thickness of 1.6 to 12 mm;

- A cooling line (16) for cooling the finished strip (15) to a coiling temperature;

- A pair of scissors (17) for cutting off the cooled

Finished tapes (15); and

- A winding device (18) for winding the finished strip (15) to bonds.

2. Cast-rolling composite plant according to claim 1, characterized

characterized in that the straight mold (2) has a

Funnel kokille is.

3. Cast-rolling composite plant according to one of the preceding claims, characterized in that the arcuate portion (4b) of the strand guide (4) has a radius of curvature R of 3 to 7 m, preferably from 4 to 6 m, more preferably from 4.5 up to 5.5 m.

4. Cast-rolling composite plant according to one of the preceding claims, characterized in that the secondary cooling at a plurality of positions within the strand guide (4) each at least two in a width direction of the

Thin slab strand (3) movable spray nozzles (19).

5. Cast-rolling composite installation according to one of the preceding claims, characterized in that in the region between the end of the horizontal section (4c) of the strand guide (4) and the roughing train (8) Wärmeisolationspanele

are attached.

6. Cast-rolling composite plant according to one of the preceding claims, characterized in that the

Descaling device (13) comprises a plurality in the width direction of the Vorbands (9) arranged Rotationsentzunderer.

7. Cast-rolling composite plant according to one of the preceding claims, characterized in that the horizontal distance between two finishing stands (Fl, F2, F3) of the finishing train (14) between 3 and 6 m, in particular between 4 and 5 m.

8. Cast-rolling composite installation according to one of the preceding claims, characterized in that the length of the

Cooling section (16) between 20 and 60 m, preferably between 20 and 40 m, is.

A process for the continuous production of a hot-rolled finished strip (15) of steel in a cast-rolling composite plant according to one of the preceding claims, comprising the steps:

- Pouring a molten steel to a thin slab strand (3) in a straight mold (2) of a continuous casting plant (1), wherein the thin slab strand (3) at the exit from the mold (2) has a liquid core, a thickness of 60 to 75 mm and a Width of 900 to 1700 mm;

- supporting and guiding the thin slab strand (3) in a strand guide (4) of the continuous casting plant (1) and cooling the thin slab strand (3) with a secondary cooling of the

Continuous casting plant (1);

- Thickness reduction of the thin slab strand (3) by a thickness reduction device (6) in the strand guide (4), wherein the thin slab strand (3) after the thickness reduction, a thickness of 50 to 70 mm and a casting speed of v _c > 4 m / min, preferably v _c > 5 m / min, particularly preferably v _c > 6 m / min, and a control or regulating device (20) of the continuous casting plant (1) sets the secondary cooling and the casting speed v _c such that the Thin slab strand (3) only solidified in a horizontal section (4c) of the strand guide (4);

- roughing of the uncut, reduced thickness,

Ententzunderten thin slab strand (3) in a roughing mill (8), wherein the thin slab strand (3) by exactly two

Rolling passes to a pre-strip (9) having a thickness of 10 to 30 mm is rolled;

- uncut passing a pendulum scissors (10) and a discharge device (11);

- Heating the Vorbands (9) to a temperature of 1050 to 1250 ° C, preferably 1150 to 1200 ° C in one

Induction furnace (12);

Descaling an upper and a lower side of the heated pre-strip (9) in a descaling device (13);

- finish rolling the uncut, descaled sliver (9) in a finishing train (14), wherein the sliver (9) is rolled by exactly three rolling passes to a finished strip (15) having a thickness of 1.6 to 12 mm;

- cooling the finished strip (15) to a coiling temperature in a cooling section (16);

- Cutting the cooled finished strip (15) by a pair of scissors (17); and

- winding the finished belt (15) into coils in one

Winding device (18).

10. The method according to claim 9, characterized in that the control or regulating device (20) by means of a mathematical model

an actual position of a sump tip along the

Transport path of the thin slab strand (3) in the

Strand guide (4) and

- An actual temperature profile along the transport path of the thin slab strand (3) in the strand guide (4) and in normal planes to it

continuously calculated and the thin slab strand (3) taking into account a desired temperature profile and a desired position of the sump tip by the secondary cooling

is cooled continuously, regulated.

11. The method according to claim 9 or 10, characterized in that the actual temperature Tl _is the finished strip (15) after the third rolling pass (F3) in the finishing train (14) and before cooling in the cooling section (16) is measured and several inductors of the induction furnace (12)

controlled temperature-controlled, so that the actual temperature Tl _Ist corresponds to a target temperature Tl _So n as possible.

12. The method according to any one of claims 9 to 11, characterized in that the thickness reduction device (6) applies a soft reduction in a region with still liquid or partially liquid core (5) of the thin slab strand (3).

13. The method according to any one of claims 9 to 12, characterized in that the actual temperature T2 _is the endless finished strip (15) after cooling in the cooling section (16) is measured and the cooling nozzles of the cooling section (16).

controlled temperature-controlled, so that the actual temperature T2 _Ist a target temperature T2 _So n as possible corresponds.

14. The method according to any one of claims 9 to 13, characterized in that the endless finished strip (15) after the

Start-up of the cast-rolling composite plant leaving the finishing train (14) with a first thickness dl, followed by the thickness of the finished belt (15) in continuous continuous operation

is progressively reduced to a second thickness d2 <dl, and before the down casting of the cast-rolling composite plant

Thickness of the finished strip (15) in continuous uninterrupted operation is gradually increased to a third thickness d3> d2.

15. The method according to claim 14, characterized in that the first thickness dl is between 3 and 12 mm, the second thickness d2 between 1.6 and 12 mm and the third thickness d3 between 3 and 12 mm.

16. The method according to any one of claims 9 to 15, characterized in that the hydrogen content in the

Molten steel before continuous casting by one

Vacuum treatment to -S 3 ppm, preferably -S 1 ppm is reduced.