WO2012095250A1

WO2012095250A1 - Equipment and method for producing hot-rolled strips

Info

Publication number: WO2012095250A1
Application number: PCT/EP2011/073723
Authority: WO
Inventors: Karl Hoen; Jürgen Müller; Ingo Schuster; Axel Weyer
Original assignee: Sms Siemag Ag
Priority date: 2011-01-12
Filing date: 2011-12-22
Publication date: 2012-07-19
Also published as: EP2663412B1; EP2663412A1; DE102011008434A1; CN103442817B; CN103442817A

Abstract

The invention relates to a device and method for producing hot-rolled strips (260), wherein the device comprises the following features: a casting machine (110) for producing at least one cast strand (120), a separating unit (125) for severing slabs (130) from the cast strand (120), a rolling train for producing the hot-rolled strip from the slabs having a width smaller than a rolling width threshold value, and a transport system comprising a distributing guide (140) for selectively transporting the slabs out of the casting machine either into the rolling train or to a special treatment unit (400). In order to allow the plant to operate more effectively, according to the invention the casting machine is designed as a twin casting machine for producing the at least one cast strand having a width that is smaller or larger than the rolling width threshold value, and a control unit is provided for the distributing guide in order to branch off the slabs having a width smaller than the rolling width threshold value into the rolling train and in order to branch off the slabs having a width larger than the rolling width threshold value for the special treatment unit.

Description

Plant and method for producing hot strip

The invention relates to a system and a method for producing hot strip, wherein a casting machine for generating at least one casting strand, a separating device for separating slabs from the casting strand, a transport system with a switching device for selectively transporting the slabs from the casting machine be used either in a rolling mill or to a special treatment facility. The rolling train is used to produce the hot strip from the slabs having a width smaller than a roll width threshold.

A production planning method for increasing the throughput in hot strip production is known from EP 1 363 750. In this process, the rolling mill is served, on the one hand, by a two-strand caster, which produces thin slabs, and, on the other, by slabs from a warehouse.

The slabs for the warehouse are produced by a twin caster, which pours thick slabs. These thick slabs are then fed to a downstream roughing unit via a reheating furnace via a slab feed device and rolled into slivers, which are fed to the rolling train in the form of coils. Although the coil feeder bypasses unplanned downtime of the caster, however A huge amount of energy is needed to heat the coils back to rolling temperature.

A cast rolling mill, which also combines continuous casting and rolling of slabs, is described in DE 693 16 703. In particular, the document describes a method for producing wound strip, sheet in wound form or discrete sheet metal plates. The casting plant is operated by single-strand casting and produces slabs of various widths, which are either placed directly in an oven to be fed to the rolling line or stored in a slab storage area. The distinguishing criterion of whether the slabs are fed from the warehouse or directly from the casting machine to the rolling line depends on the production capacity of the casting machine. The slabs from the warehouse are used during production breaks of the casting machine for utilization of the connected rolling mill.

A disadvantage of the known casting rolling, however, is that the maximum width of the casting strands is matched to the width of the rolling mills, the casting mill is inflexible in production and thus no increase in capacity can be achieved. Another disadvantage is that an energy-saving driving style is hardly possible by a plurality of ovens in the system for reheating the cold slabs or coils.

The object of the invention is to develop a known system and a known method for producing hot strip, to increase the production capacity and increase the flexibility already in the production to achieve the cast strand and offer an energy-saving configuration of the plant, which thus produces cost-effectively.

This object is achieved by the subject matter of claim 1. This article is characterized in that the casting machine is designed as a twin casting machine for producing the at least one casting strand with a bend that is smaller or greater than the rolling width threshold value and that a first control device for the switch device is provided for branching the slabs having a width smaller than the roll width threshold into the rolling train and for branching the slabs having a width greater than the roll width threshold for the special treatment device.

The description of the invention is based on the following terms:

Roll width threshold:

The width of the slabs to be rolled is predetermined or limited by the width of the rolling train, in particular the width of the finishing train. The roll width threshold corresponds to the maximum width of the hot strip that can be processed in the finishing train.

Special treatment facility:

The slabs, whose width is greater than the rolling width threshold, are not transferred to the connected rolling train, but are instead converted into a special rolling mill. treatment facility. This special treatment device can be an external slab stock, a special rolling mill for slabs of this width o.ä. be.

That according to claim 1, the casting machine is designed as a twin-casting machine, offers the advantage that not only in the single-strand process can be produced, but also in the two-strand process, the twin casting process. This application of the twin-casting machine offers the advantage of achieving increased flexibility in slab production, both in width and in speed. The subsequent Weichenein- direction, which is provided for branching the slabs m with a width smaller than the roll width threshold in the line of the rolling mill, offers the advantage that the slabs can be fed without significant temperature losses directly to the rolling train or that the slabs m It can be diverted to a width greater than the roll width threshold for the special treatment device. This results in an increased flexibility in slab production. The productivity of the rolling mill is still fully guaranteed since the rolling mill is served from a first stock with slabs if the supply of slabs from the twin-casting machine is insufficient.

Characterized in that according to a first embodiment, the twin casting machine is arranged offset to the line of the rolling train and a transport system with a first feeder, for example, a Querverfahreinrichtung is provided, in this way, all slabs produced with a width smaller than the roll width threshold directly to the rolling train be fed and all slabs with a width greater than the Walzbreiten- Threshold further procedure in the special treatment facility. Due to the first feeding device of the transport system, the slabs from the twin casting machine immediately enter a holding furnace and only have to be heated to rolling temperature in an energy-saving manner.

Advantageously, a holding furnace for holding the slabs having a width smaller than the rolling width threshold is designed such that the slabs are heated to rolling temperature with little energy. The design of the stove not only refers to the heating performance, but also to a short structural design of the holding furnace.

Advantageously, the rolling train at least one of the following components, preferably in the direction of passage of the slabs seen in the order mentioned:

a descaling device

- A compression device

- A reversing roll stand

- A conveyor before and / or behind the Reversierwalzgerüst; - a finishing train By a local arrangement of the rolling train to the casting machine transport routes are avoided and thus prevents cooling of the slabs, resulting in energy savings.

Advantageously, the transport system further comprises a second feeding device for bread with a breadcrimber as the threshold value from a first storage in the rolling train, so that in a production of slabs with a width greater than the roll width threshold by the twin casting machine, the downstream rolling mill remains fully loaded. Of course, this also applies to production pauses of the twin casting machine.

Advantageously, the second feeding device is formed with a second control device, which makes it possible that the feeding of the slabs from the first bearing into the rolling train is made possible when the rolling train alone is not loaded with slabs from the twin casting machine. This is true, for example, when the twin caster produces slabs that are wider than the roll width threshold. For this it is advantageous that the rolling mill can produce decoupled from the twin casting machine.

Advantageously, the casting machine for a special treatment device, which is designed either as a second bearing or as a special processing line, including a rolling mill, for processing the slabs having a width greater than the roll width threshold. This results in a great flexibility in the slab production and a better utilization of the twin casting machine. The above object is further achieved by the method claimed in the independent method claim 8.

The advantages of this procedural solution correspond to the advantages mentioned above with respect to the device. Further advantageous embodiments of the method and the apparatus of the invention are specified in the subclaims.

The description is a total of a figure attached, wherein

Figure 1 shows the plant according to the invention

shows.

The system according to the invention and the method according to the invention are described in detail below with reference to the figure.

1 shows a plant 100 for producing hot strip 260. The main components of the plant 100 are a twin casting machine 110, a connected rolling train 210-250, a holding furnace 200, a special treatment device 400, a first bearing 300 and a heating furnace 310. The Twin Caster 1 10 is located near rolling line 210-250 and produces casting strands 120 in the twin casting process or in the single strand process. The casting strands 120 are separated from a separating device 125 into slabs 130 and then fed by a switch device 140, which is controlled by a first control device 150, via the holding furnace 200 to the rolling train 210-250 or the special treatment device 400. The twin casting machine 1 1 0 is preferably designed as a sheet system, for example with a casting radius of 4.5 to 7.0 m.

If the twin casting machine 1 produces 10 casting strands 120 in the single or twin casting process having a width smaller than the width of the rolling width threshold value, the slabs 130 subsequently separated from the separating device 125 can be set by the transport system with a corresponding setting predetermined by the first control device 150 the diverter device 140 via a first feed device 1 70, for example, a cross-conveyor, are fed through the holding furnace 200 directly to the rolling train 210-250. After being heated to rolling temperature in the holding furnace 200, the slabs 130 are descaled by a descaling device 210 and fed to a reversing mill 230 and m at least one conveyor 240 by a squeezing device 220, which is optional, and subsequently fed to a finishing mill 250 for rolling Hot strip 260 introduced. The subsequent winding of the hot strip 260 from a coiler to coils 270 is shown here only schematically at the end of the rolling train 210-250.

The twin casting machine 1 10 can pour in the single-strand process a maximum width of the casting strands 120 of preferably 3600 mm. This maximum Width of the produced casting strands 120 and the slabs 130 subsequently severed by the severing means 125 is above the maximum width of the hot strips 260 to be produced. Because the rolling train 210-250 can only process slabs 130 having a width smaller than a roll width threshold, for example 2200 mm, slabs 130 having a width greater than the roll width threshold are diverted from the switch 140 to the special treatment device 400.

In particular, while the twin caster 1 1 0 is producing slabs 1 30 m in width with a width greater than the roll width threshold, cold slabs 1 30 can be removed from the first bearing 300 by means of a second feeder 1 80 via a heating furnace 310, which is designed for example as Hubbalkenofen or puncture furnace, are fed into the rolling mill 21 0-250. The slabs 130 from the first bearing 300 have a width that is less than or equal to the roll width threshold. The heating furnace 310 is designed for slabs 130 of these widths and preferably heats the slabs 130 to a temperature for hot rolling of 1100 ° C to 1250 ° C. After being heated to rolling temperature, the slabs 130 are processed from the rolling train 210-250 to hot strip 260.

While the rolling train from the first bearing 300 produces hot strip 260 from the slabs 1 30, the twin casting machine 1100 preferably operates in the so-called "plate production" mode, that is, the twin casting machine 1100 casts pouring strands 120 having a width greater than that Walzbreiten threshold of the rolling mill, but preferably less than or equal to 3600 mm, which - separated from slabs 130 - from the switch device 140, controlled by the first control device 150 to the special treatment direction 400 brought / branched off. The "slab production" slabs 130 can not be rolled from the connected mill 210-250 due to their too large width.

In the claimed system concept, the flexibility of the entire system 100 is increased and the productivity of the rolling mill 21 0-250 remains fully guaranteed. By feeding the slabs 130 from the first bearing 300 and then further processing this slab in the rolling train 210-250 while the twin-casting machine 110 operates in the "slab production" mode, production amounts of 5.0 million tons per year can be represented - len.

On the other hand, if the twin casting machine 1 1 0 operates in the twin casting process, two parallel casting strands 120 each having a width of preferably 1750 mm and, for example, a thickness of 100 mm, corresponding to a web width of the twin casting machine of 1 00 mm, cast. Any uneven temperatures of the slab narrow sides / edges are homogenized by the holding furnace 200, which is preferably designed as Hubbalkenofen before use in the rolling mill 21 0-250. The slabs 130 from the twin-casting process have a slab width that is smaller than the roll width threshold. Due to the spatially close arrangement of twin casting machine 1 10 and holding furnace 200, the slabs 130 of the rolling mill 21 0-250 are supplied without cooling to room temperature and the temperature losses are reduced to a technological minimum. This also applies to slabs 130 from the single-strand process, which have a width smaller than the roll width threshold and are rolled from the connected rolling train to hot strip 260. The twin casting machine 10 according to the invention produces casting strands 120 with a thickness of preferably 100-170 mm. The generated slab thickness is selected so that the roughing to the required intermediate thickness for the finish rolling with m inimalen number of stitches in the Reversierwalzgerüst 230 is possible. Particularly preferred is a slab thickness of 150 mm is provided. Between the roughing passes, the intermediate belt is moved in the conveyor 240, which is preferably designed as a roller table, actively heated roller table, roller hearth furnace or tunnel kiln.

LIST OF REFERENCE NUMBERS

100 plant

1 10 twin caster 120 cast strand

125 separating device

130 slabs

140 switch device 50 first control device for switch device 170 first feeder, preferably cross-conveyor

180 second feeder

185 second control device

200 holding furnace

210 descaling device 220 compression device

230 Reversing rolling stand

240 conveyor

250 finish rolling mill

260 hot strip 270 coil first camp

heating furnace

Sonderbehandlungseinrichtu

Claims

claims:

An apparatus (100) for producing hot strip (260), comprising:

a casting machine for producing at least one casting strand (120);

a separator (125) for separating slabs (130) from the cast strand (120);

a rolling train (210-250) for producing the hot strip (260) from the slabs (130) having a width less than a roll width threshold; and

a transport system having control means (140) controlled by a controller for selectively transporting the slabs (130) from the casting machine either into the rolling line or to a special treatment device (400);

characterized in that

the casting machine is configured as a twin casting machine (110) for producing the at least one casting strand (120) having a width that is smaller or larger than the roll width threshold value; and the switch means controller (150) is arranged to branch the slabs (130) having a width smaller than the roll width threshold into the rolling line and to branch the slabs (130) having a width greater than the rolling width threshold for the special treatment device (400).

2. Plant (100) according to claim 1, characterized in that the twin casting machine (1 10) is arranged offset to the line of the rolling train; and in that the transport system comprises a first feeder (170), for example a cross-conveyor, for the slabs (130) having a width smaller than the roll width threshold for feeding the slabs from the twin-casting machine (110) into the line the rolling mill.

3. Plant (100) according to one of the preceding claims, characterized by a holding furnace (200) for keeping the slabs (130) having a width smaller than the roll width threshold, during their transport from the twin casting machine (1 10) in the Line of rolling mill.

4. Plant (100) according to one of the preceding claims, characterized in that the rolling train has at least one of the following components:

a descaling device (210);

- a compression device (220);

a reversing roll stand (230);

- A conveyor (240) before and / or behind the Reversierwalzgerüst (230);

- A finishing mill (250) for rolling the slabs (130) with a

Width that is less than the roll width threshold.

5. Plant (100) according to one of the preceding claims, characterized in that

the transport system has a second feed device (180) for slabs

(130) having a width smaller than the roll width threshold from a first bearing (300) in the rolling train; and a heating furnace (310) is provided for heating the slabs

(130) from the first bearing (300) to a suitable rolling temperature for rolling the slabs (130) in the rolling train.

6. Plant (100) according to claim 5,

characterized in that

a second control means (185) for the second supply means (180) is provided and adapted to allow the supply of the slabs (130) from the first bearing (300) in the rolling train, when the rolling train alone with slabs (130) from the Twin casting machine (1 10) is underutilized.

Plant (100) according to one of the preceding claims,

characterized in that

the special treatment device (400) is either designed as a second bearing or is designed as a special processing line, including a rolling mill, for processing the slabs (130) having a width greater than the roll width threshold value.

8. A method for operating a plant (100) for producing hot strip (260), comprising the following steps:

- generating at least one casting strand (120);

- separating slabs (130) from the casting strand (120);

- Transporting the slabs (130) either for rolling in a rolling mill (210-250) or for a special treatment;

- rolling the slabs (130) with a width smaller than a Walzbreiten-

Threshold to Hot Strip (260); and

marked by, Producing the at least one casting strand (120) on a twin casting machine (110) having a width greater or smaller than the rolling width threshold value;

Branching the slabs (130) having a width which is smaller than the predetermined roll width threshold for rolling in the rolling train; and

Branching the slabs (130) having a width greater than the predetermined roll width threshold to the special treatment.

9. The method according to claim 8,

characterized in that

the slabs (130), whose width is smaller than the roll width threshold, are heated to rolling temperature before being fed into the mill train in a holding furnace (200).

10. The method according to claim 8,

characterized in that

during breaks in production of the twin caster (110), the rolling train is operated from a first bearing (300) with slabs (130) having a width which is less than the predetermined roll width threshold.

1 1 .Method according to claim 10,

characterized in that

the slabs (130) are heated from the first bearing (300) to rolling temperature before rolling.