TW201711766A - Installation based on the CSP concept and method for operating such an installation - Google Patents

Abstract

The invention relates to an installation and a method for producing metal strips, preferably steel strips, of a thickness of 0.8 to 25 mm in batch mode or semi-continuous mode, comprising at least one casting machine for casting thin slabs and a rolling device arranged downstream of the at least one casting machine and comprising a number of rolling stands for rolling thin slabs into metal strips of a predetermined thickness, and also at least one coiling device arranged downstream of the rolling device, wherein a shear and a furnace are arranged between the at least one casting machine and the rolling device, wherein the rolling device has a device for changing the roll gap of at least one rolling stand during the rolling operation and there is a control device, which controls the installation in such a way that switching over from batch mode to semi-continuous mode or back takes place according to the grade of metal, preferably the grade of steel, and the desired thickness of the metal strip to be produced, and that the switching over from batch mode to semi-continuous mode can take place in the course of the rolling operation by the rolling device.

Description

Device according to CSP-concept and method for operating such device

The present invention relates to an apparatus and a method of producing a metal strip, preferably a steel strip, having a thickness of 0.8 to 3.0 mm in a batch or semi-continuous operation with a pre-cast thin slab having a thickness of 40-140 mm. The invention also relates to a method for operating such a device.

For a period of time, so-called CSP-® equipment has been used for the manufacture of thin strips of the type described in the opening paragraph having a thickness of 0.8 to 3.0 mm, a width of preferably not more than 2000 mm, preferably about 1880 mm (+/- 2%). The material enables the production of such thin strips based on the compact equipment concept with high productivity and excellent strip quality, especially in an economical and environmentally friendly manner. The abbreviation CSP-® stands for "Compact Strip Production". In the case of CSP-® equipment, the liquid steel is cast into a thin slab which is rolled into a thin strip directly in the rolling mill without pre-rolling in the tunnel furnace after temperature compensation. By connecting the casting directly to the rolling, the main feature of the CSP-® device is the exceptionally low energy consumption – up to 40% energy savings compared to conventional strip hot rolling mills. The CSP-® equipment concept pre-rolls thin slabs even without pre-rolling frames, reducing investment costs. Another feature of the tropical materials produced on CSP-® equipment is its high quality, which has a balanced structure and uniform mechanical and physical properties in terms of total belt length and bandwidth. The strip geometry is within the minimum tolerances.

In this field, the present invention is directed to an apparatus that is operable in both batch and semi-continuous operations, and in particular, can switch between such types of operations.

In the related art, the following operation mode of the device is referred to as so-called batch operation: in this mode of operation, the thin slab discharged from the casting machine is shortened to a certain length according to the specific thickness and before entering the downstream tunnel furnace. In order to roll up the coil having a predetermined length and a predetermined weight in the downstream take-up device after leaving the rolling device. In this way, each slab is just made into a coil in the batch operation.

A person skilled in the relevant art generally refers to a mode of operation of such a device as a so-called semi-continuous operation in which a thin slab is cut in some manner after leaving the casting machine, thereby producing a so-called giant slab, The length is usually an integer multiple of the slab in the batch operation. In the subsequent rolling process, the giant slab, which is also introduced into the tunnel furnace after being discharged from the casting machine, is rolled into a thin strip, which is usually left by the shearing machine after leaving the rolling device. The thin strip is cut to the corresponding coil weight and coil length.

This type of equipment is used to manufacture thin strips of different thicknesses from different grades and from low carbon steel to advanced high strength steel grades.

Over the years, equipment for the manufacture of thin metal strips of pre-cast thin slabs has been known to those of ordinary skill in the relevant art. The same is true for CSP-® devices.

For example, EP 2 195 124 B1 describes a compact flexible CSP-® device for continuous, semi-continuous and batch operation. The equipment described in this case is designed such that it can be operated in all three possible types of operation for this type of equipment, where for batch operations there are usually two parallel castings in front of the rolling device. Machine, a shearing machine is arranged before the casting machine and the rolling device to start the rolling operation in a manner independent of the casting speed of the thin slab Work. In order to carry out the semi-continuous operation, it is also necessary to allow the length of the giant slab to be made, that is, the length of the individual slab which is longer than the batch operation. Finally, the continuous operation of such a device forcibly requires that the heating device, in particular the inductive heating device, be arranged in the region of the rolling direction, usually between a single rolling frame or at least between the groups of rolling frames.

WO 2011/141790 A2 also describes a method and an apparatus for manufacturing a flat rolled product that also implements the CSP-device concept. In this device, switching between all three of the above types of operations also works under certain conditions.

The use of conventional equipment and conventional methods for operating such equipment presents the following difficulties: only semi-continuous operation can be applied by heating the roller to a predetermined operating temperature, otherwise, particularly in the following rolling frames There will be interference: the rolling gap is completely closed by applying pre-stress as appropriate, so that the thinner belt thickness sought can be achieved when the corresponding rolling frame is operated and rebounded due to the rolling pressure acting on the metal strip. . Particularly in high-strength steel grades, for example, since the strip head is not smoothly inserted into the rolling gap, the start of the semi-continuous operation sometimes causes interference of the rolling operation.

In view of this, it is an object of the present invention to provide an apparatus and method of operating the same that can overcome the aforementioned problems reliably when operating a CSP-® device. The solution to achieve the above object of the present invention resides in an apparatus comprising the features of claim 1 and a method comprising the features of claim 8 . Advantageous embodiments of the invention are directed to the description and the dependent items.

According to the present invention, in the case where the rolling apparatus is at the operating temperature and the final thickness within the target range of the minimum final thickness has been previously achieved in the batch operation, the Semi-continuous operation. The first final thickness in the semi-continuous operation is preferably the final final thickness in the batch operation, wherein at least the rolling gap of the rolling frame is adjusted, preferably the plurality of rolling gaps of the rolling frame This minimum final thickness is adjusted by subsequent implementation of the so-called "flying-gauge-change" and this is achieved in the thin strip.

Preferably, the strip is separated in a coil by a suspended shear arranged behind the rolling device, the shear being arranged in front of the take-up device, in particular the conventionally used underground coiler.

In another preferred embodiment of the invention, the strip thickness variation is performed in some manner during the rolling operation such that the strip head and the strip tail are also within market thickness tolerances.

In view of the above, the present invention provides a method and an apparatus having a correspondingly programmed control device that can switch from the batch operation to the semi-continuous operation, with the minimum final thickness after the present invention Making a portion of the pre-cast giant slab, preferably at least half of the giant slab, without the need for external energy to cause the tropical material to reach operating temperature; rather, in the manufacture of the metal strip The operating temperature of the apparatus of the present invention, particularly the operating temperature of its rolled material, is adjusted during batch or semi-continuous operation by selecting the correct rolling speed.

Thus, with the apparatus of the present invention and the method of the present invention, the thin strip can be manufactured with minimal energy consumption in an energy efficient mode of operation with the use of conventional equipment components and correspondingly usable components.

Thus, the apparatus of the present invention is capable of producing thin strips from a plurality of steel grades in the batch operation as well as in a semi-continuous operation, and producing a particularly small thickness in an energy-saving manner. According to the Steel quality and the final product, in principle selecting the type of operation for the batch operation for larger final thicknesses, selecting the type of operation for semi-continuous operation for smaller or smallest final thicknesses, wherein after applying the invention, two parallel arrangements are applied In the case of a casting machine, the equipment can provide a total production capacity of approximately 4 million tons per year in a two-line operation.

In a preferred embodiment of the invention, the rolling device has two sets each having a plurality of rolling frames, in particular a first group having two rolling frames and a downstream portion disposed in the first group. The second group of up to 5 rolling stands. An inductive heating device, preferably extending from the rolling device and the entire rolling line, may be disposed between the groups of rolling stands. The inductive heating device is typically not applied in the batch operation, but the inductive heating device can be applied in the semi-continuous operation, particularly in the case of producing a smaller and minimum final thickness of the metal strip through the rolling device. The structure for the tropical material is maintained in the area of the Vostian phase over the entire rolling process.

In another preferred embodiment of the present invention, during the rolling operation, that is, if the strip is engaged with one or more rolling frames of the rolling device, switching from the batch operation To this semi-continuous operation. Preferably, the switching is carried out after rolling a plurality of, preferably two or more, particularly preferably two to two semi-single slabs. That is, in the case of a giant slab cast for the semi-continuous operation and cut by a shearer set after the casting machine, having a standard size of, for example, five individual slab lengths, in the semi-continuous At least half of the coils produced from the giant slab are manufactured to the desired minimum final thickness during operation.

Preferably, after the last rolling frame and in front of the winding device, a shearing machine, preferably a suspended type, is arranged, and the manufactured thin strip can be cut by the shearing machine to achieve the coiled roll. The desired length is to process the rolled thin strip.

Preferably, the length of the furnace is distributed between the casting machine and the rolling device The degree is such that it is at least the length of the giant slab in order to perform the semi-continuous operation. The length of the giant slab is usually a multiple of the length of a single slab, wherein the length of the furnace, preferably the length of the tunnel furnace, is so distributed that it accommodates a longer single slab (single slab has a maximum of 40 mm) The thickness of the giant slab is five times the length. Such tunnel furnaces typically have a length of about 250 m.

The method of the invention is preferably carried out on the aforementioned apparatus of the invention. The effects achievable by the method of the present invention are the same as those achieved with the apparatus of the present invention.

In the method of the present invention, the thin slab is preferably rolled to leave the thin strip of the casting machine or the parallelly arranged casting machines at a thickness of 40 to 140 mm. This provides a method which provides the largest possible product mix depending on the final thickness that can be achieved and on the steel grade to be processed.

Preferably, the apparatus manufactures a steel strip of the "low carbon steel" steel grade, preferably a steel strip having a thickness of 0.8 to 1.2 mm in the semi-continuous operation and a thickness greater than 1.2 mm in the batch operation Steel strip.

It is also preferred to employ a method in which the apparatus manufactures a steel strip of the "medium carbon steel" steel grade, preferably in a semi-continuous operation, to produce a steel strip having a thickness of 1.4 to 1.8 mm and to be manufactured in the batch operation. Steel strip with a thickness greater than 1.8 mm.

It is also preferred to employ a method in which the apparatus manufactures a steel strip of the "high carbon steel" steel grade, preferably in the semi-continuous operation, to produce a steel strip having a thickness of 1.4 to 2.0 mm and to be manufactured in the batch operation. Steel strips with a thickness greater than 2.0 mm.

It is also preferred to employ a method in which the apparatus manufactures a steel strip of the "high-strength low-alloy steel" steel, preferably in the semi-continuous operation, a steel strip having a thickness of 1.4 to 2.0 mm and operating in the batch A steel strip having a thickness greater than 2.0 mm is produced.

It is also preferred to employ a method in which the apparatus manufactures a steel strip of the "advanced high-strength steel" steel, preferably in the semi-continuous operation, a steel strip having a thickness of 1.4 to 2.5 mm and in the batch operation A steel strip having a thickness greater than 2.5 mm is produced.

1‧‧‧ casting machine

2‧‧‧Shearing machine

3‧‧‧Tunnel Furnace/Roller Bottom Furnace

4‧‧‧Oxide removal machine

5‧‧‧Rolling frame group/rolling frame group

6‧‧‧Separate Shear/Shear

7‧‧‧Inductive heating device

8‧‧‧Rolling frame set

9‧‧‧Laminar cooling section

10‧‧‧High speed shears

11‧‧‧ Underground coiler

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a CSP-® apparatus of the present invention, and Figure 2 is a tabular list of fabricated strips of thick and machinable steel grades, classified according to the respective types of operation of the apparatus of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described in detail with reference to the accompanying drawings, in which FIG.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a CSP-® apparatus of the present invention which is capable of further processing a steel grade cast into a thin slab through a casting machine into a thin strip having a desired final thickness in batch operation and semi-continuous operation. A shearing machine 2 for separating the thin slabs before the thin slab enters the roller hearth furnace 3 is provided after two casting machines 1 which are arranged in parallel to at least the batch operation and fed to the apparatus. These roller hearth furnaces or tunnel furnaces 3 are used for both subsequent heating and for equalizing the temperature of the thin slab. At least the length of the upper tunnel furnace 3 is set such that at least one giant slab can be completely accommodated in the tunnel furnace 3 for semi-continuous operation. The lower tunnel furnace 3 located directly downstream of the parallel casting machine 1 can also have this length, but must be at least the length of a single slab for batch operation so that the single slab can be accommodated during batch operations and It is heated. The second tunnel furnace 3 can also be used as a buffer for the upper casting machine-tunnel furnace arrangement schemes 1 and 3 between the tunnel furnaces 3 through suitable switching devices. Device. Downstream of the upper tunnel furnace 3 and in front of the group 5 of rolling stands, a scale remover 4 for removing surface scale is provided in order to positively influence the rolling in the group 5 of the first roll stand, in particular Keep free of scale-related surface damage. A shearing machine 6 is arranged downstream of the first rolling frame set 5 for trimming the strip head and the strip tail of the intermediate strip pre-rolled in the rolling frame set 5 for easy stripping Pass through in the second rolling frame set 8. Furthermore, the separating shear 6 can be used to roll the first rolling frame set 5, in particular according to the entry speed of the intermediate strip entering the second rolling frame set 8 after being discharged from the first rolling frame set 5 The operation is separated from the rolling operation in the second rolling frame set 8. In addition, an inductive heating device 7 is disposed between the first rolling frame group 5 and the second rolling frame group 8. In the case where the inductive heating device 7 is required to perform the rolling process, it is preferably The inductive heating device is removed from the rolling line. This is typically the case when the apparatus of the invention is operated in a batch operation or subsequently in a semi-continuous operation with a relatively large thickness of 2 to 2.5 mm. A laminar cooling section 9 for adjusting the desired take-up temperature for the thin strip is arranged in the second rolling frame set 8. The laminar cooling section 9 is preferably provided with means for controllably enhancing the cooling of the thin strip, typically a liquid nozzle or nozzle capable of plating a mixture of air and coolant onto the thin strip. Between the laminar cooling section 9 and the two separate underground coilers 11, a high speed shear 10 for separating the rolled thin strips into the desired coil length is disposed.

Figure 2 exemplarily shows a list of steel grades that can be processed on the apparatus of the present invention and that can be processed in the method of the present invention, and a thick gauge format produced by the apparatus, wherein given a semi-continuous operation and batch operation Certain steel grades and certain strip thicknesses are made in the type of operation. In principle, it is possible to produce "low carbon steel" steel grades in a semi-continuous operation in batch operations and in a thickness range of 0.8 mm to 1.4 mm with a final thickness of more than 1.4 mm. Also in the thickness range of 1.4mm to 2.5mm The “advanced high-strength steel” steel grade is manufactured in the semi-continuous operation.

1‧‧‧ casting machine

2‧‧‧Shearing machine

3‧‧‧Tunnel Furnace/Roller Bottom Furnace

4‧‧‧Oxide removal machine

5‧‧‧Rolling frame group/rolling frame group

6‧‧‧Separate Shear/Shear

7‧‧‧Inductive heating device

8‧‧‧Rolling frame set

9‧‧‧Laminar cooling section

10‧‧‧High speed shears

11‧‧‧ Underground coiler

Claims (19)

An apparatus for producing a metal strip having a thickness of 0.8 to 3.0 mm in the batch or semi-continuous operation and producing a thickness greater than 2.5 mm in the batch operation, preferably a steel strip, including at least one for casting a sheet a casting machine for a blank and a rolling device disposed downstream of the at least one casting machine having a plurality of rolling frames for rolling the thin slabs into metal strips of a predetermined thickness, and at least one disposed on the rolling device a downstream winding device, wherein a shearing machine and a furnace are disposed between the at least one casting machine and the rolling device, wherein the rolling device has a function for changing at least one rolling during the rolling operation a device for rolling the gap of the frame, and a control device for controlling the device such that the desired thickness of the metal strip to be manufactured is switched from the batch operation to the metal type The semi-continuous operation, or the self-semi-continuous operation is switched to the batch operation, and the rolling operation is switched from the batch operation to the semi-continuous operation during the rolling operation. The apparatus of claim 1, wherein the rolling device has two sets each having a plurality of rolling frames, preferably a first group having two rolling frames and disposed at the first A second group of up to 6 rolling stands downstream of the group. The apparatus of claim 2, wherein an inductive heating device preferably extending from the rolling device is disposed between the groups of the rolling frame. An apparatus according to any one of the preceding claims, characterized in that, during the rolling operation, a plurality of rolls, preferably two or more, particularly preferably 2 to 5 individual slabs, may be The batch operation switches to the semi-continuous operation. An apparatus according to any one of the preceding claims, characterized in that a shearing machine, preferably suspended, is arranged behind the last rolling frame and in front of the winding device. An apparatus according to any one of the preceding claims, characterized in that the length of the furnace, preferably the tunnel furnace, is designed such that it is at least the length of the giant slab in order to carry out the semi-continuous operation. A device according to any one of the preceding claims, characterized in that the device adopts a construction scheme according to the CSP-device concept. A method for operating an apparatus as claimed in any one of claims 1 to 7 for manufacturing a thickness of 0.8 to 3.0 mm in the batch or semi-continuous operation and in the batch In operation, a metal strip having a thickness greater than 2.5 mm, preferably a steel strip, is produced, the apparatus comprising at least one casting machine for casting a thin slab and a plurality of castings downstream of the at least one casting machine for rolling the thin slab a rolling device for a rolling frame of a metal strip of predetermined thickness, and at least one winding device disposed downstream of the rolling device, wherein a shearing machine is disposed between the at least one casting machine and the rolling device a furnace characterized by changing a rolling gap of at least one rolling frame during the rolling operation, and the control device controls the device in such a manner that, depending on the metal type, preferably a steel type, and the metal strip to be manufactured The desired thickness is switched from the batch operation to the semi-continuous operation, or from the semi-continuous operation to the batch operation, and by the rolling device switching from the batch operation to the rolling operation during the rolling operation Semi-continuous operation . The method of claim 8 is characterized in that, during the rolling operation, a plurality of rolls, preferably two or more, particularly preferably 2 to 5 individual slabs, are completed from the batch The operation switches to the semi-continuous operation. The method of claim 9, wherein the rolling device, particularly the working roller of the respective rolling frame, is at a predetermined operating temperature during the batch operation, in the rolling Switching from the batch operation to the semi-continuous operation during the press operation. The method of any one of claims 8 to 10, wherein the thin slabs have a thickness of 40 to 140 mm after leaving the at least one casting machine. The method of any one of clauses 8 to 11, wherein the at least one rolling gap is changed during the rolling operation such that the strip tail of the pre-rolled metal strip and the subsequent The strip heads of the metal strip are within these required thickness tolerances. The method of any one of claims 8 to 12, characterized in that the apparatus manufactures a steel strip of the low carbon steel grade, preferably in the semi-continuous operation, a steel having a thickness of 0.8 to 1.2 mm The belt and the steel strip having a thickness greater than 1.4 mm were produced in the batch operation. The method of any one of claims 8 to 12, characterized in that the apparatus manufactures a steel strip of the medium carbon steel grade, preferably in the semi-continuous operation, a steel having a thickness of 1.4 to 1.8 mm The belt and the steel strip having a thickness greater than 2.0 mm were produced in the batch operation. The method of any one of claims 8 to 12, characterized in that the apparatus manufactures a steel strip of the high carbon steel grade, preferably in the semi-continuous operation, a steel having a thickness of 1.4 to 2.0 mm. The belt and the steel strip having a thickness greater than 2.5 mm were produced in the batch operation. The method of any one of claims 8 to 12, characterized in that the apparatus manufactures a steel strip of the high strength low alloy steel grade, preferably in a thickness of 1.4 to 2.0 mm in the semi-continuous operation. The steel strip and the steel strip having a thickness greater than 2.5 mm were produced in the batch operation. The method of any one of claims 8 to 12, characterized in that the device system A steel strip of this advanced high strength steel grade having a thickness of 1.4 to 2.5 mm is preferably produced in the semi-continuous operation. The method of any one of claims 8 to 17, wherein the metal strip is manufactured in the batch operation without inductive heating of the strip, only in the semi-continuous operation. In the case of manufacturing a high-strength steel having a small thickness, preferably in the case of manufacturing a high-strength low-alloy steel having a thickness of 1.4 to 1.6 mm or an advanced high-strength steel having a thickness of 1.4 to 1.8 mm, the inductor is used. Heating to make metal strips. The method of any one of claims 8 to 18, characterized in that the rolling device is fed from two casting machines in the batch operation.