RU2776937C1 - Combined continuous casting and rolling unit with carousel winder - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy. Combined continuous casting and rolling plant for manufacturing a hot-rolled finishing strip with a thickness of less than or equal to 1 mm, contains a continuous casting installation (1), multi-stand roughing (5) and finishing (11) lines of rolling stands, a section (13) for cooling the finishing strip, shears (16) for transverse separation of the finishing strip and a carousel winder (18). The finishing strip is wound on the first and second drums (21a, 21b) of the carousel winder, each of which has a separate rotary drive (20a, 20b) for rotation around its axis (22a, 22b), and the carousel winder (18) has a rotary drive for joint rotation of the drums (21a, 21b) of the winder around a common axis of rotation (28) along an elliptical, preferably circular path (29). The individual rotary drives (20a, 20b) of the winder drums are variable speed drives.

EFFECT: use of a carousel winder results in an even temperature distribution of the finishing strip and eliminates the need to change the direction of the strip relative to the winder, resulting in improved strip quality and installation reliability. By reducing the distance between the shear and the winder, the installation is compact.

12 cl, 3 dwg

Description

Application area

This invention relates to the field of combined continuous casting and rolling plants. In combined continuous casting and rolling plants, the continuous casting plant is connected in-line to at least one rolling mill, but more often to two rolling mills. In a continuous casting plant, liquid steel is usually cast into a cast billet with a slab or thin slab cross-section. The billet cast by continuous casting is finished-rolled in said at least one rolling mill by hot rolling into a finished strip. Due to the in-line connection of a continuous casting plant with a rolling mill, combined continuous casting and rolling plants can be made extremely compact. Since such a continuous casting plant can achieve high casting speeds, said combined continuous casting and rolling plant has a high productivity.

State of the art

In combined continuous casting and rolling plants according to the state of the art, the finished strip is usually wound on several, for example two or three coilers. These winders are located one behind the other behind the cooling section; the drums of the coilers are located under the so-called line of passage of the finishing strip (which is why they are also called underground coilers). During operation of the combined continuous casting and rolling plant, the first finishing strip is wound on the first winder. Shortly before this first reel reaches its capacity, the finishing strip is split transversely and the subsequent section of the finishing strip is directed to the next reel, which is located either before or after the first reel. The section of the finishing strip leading in front is wound on the first winder. In particular, at high mass flow in combination with thin finished strip, high transport speeds of the finished strip on the roller table of the combined continuous casting and rolling plant are ensured. After splitting the finishing strip in the transverse direction, the head part of the finishing strip is not pinched between the shears and the following winder, so that, in particular at high transport speeds, it can happen that the head part of the strip is not picked up from the winder drum. In this case, it is required to immediately stop the hot rolling, which greatly reduces the reliability and productivity of the combined continuous casting and rolling plant.

From DE 195 18 144 A1 a combined continuous casting and rolling plant is known which is suitable for producing hot-rolled finished strips with a thickness between 1.6 and 40 mm. According to one embodiment, behind the cooling section and the shears, there is a carousel winder for winding up the divided strip.

How should prior art combined continuous casting and rolling plants be modified to be suitable for producing very thin hot-rolled finishing strip with a thickness of ≤1 mm, preferably ≤0.8 mm, preferably even ≤0.6 mm, and how reliability can be increased such a combined continuous casting and rolling plant for the production of very thin hot-rolled finishing strip at high mass flows does not follow from the prior art.

Disclosure of the essence of the invention

The object of the invention is to increase the reliability of a combined continuous casting and rolling plant, in particular of the Arvedi ESP type, in the production of very thin (≤1 mm thick) hot-rolled finishing strip at high mass flow.

This problem with regard to the device is solved by a combined installation of continuous casting and rolling according to paragraph 1 of the claims. Preferred embodiments are the subject of the dependent claims.

Specifically, the combined continuous casting and rolling plant for producing hot-rolled finishing strip with a thickness of ≤1 mm, preferably ≤0.8 mm, particularly preferably ≤0.6 mm, has the following structural parts:

- a continuous casting plant with an arcuate guiding billet for continuous casting of a billet cast by the continuous casting method with a cross section of a slab or thin slab from steel melt,

- a multi-stand roughing line of rolling stands for rough rolling of a cast billet into a rough strip,

- a multi-stand finishing line of stands for finishing rolling of a rough strip into a finished strip,

- cooling section for cooling the finishing strip,

- shears for separating the finishing strip in the transverse direction, with the shears located in the direction of the material flow behind the cooling section. Such a combined continuous casting and rolling plant, in the light of the specified technical problem, is further improved in the direction that in the direction of the material flow, behind the shears, a carousel winder is located for winding the finishing strip on the first and second winder drums, each winder drum having a separate rotary drive for rotating the drum. winder around its axis of rotation, and the carousel coiler has a rotary motion drive for joint rotation of the coiler drums about a common axis of rotation in an elliptical, preferably circular path.

A carousel coiler with at least two coiler drums is used instead of several coilers arranged one behind the other in the direction of transport of the finishing strip. Each drum of the carousel winder according to the invention has a separate drive (for example, a hydraulic motor or an electric motor) for rotating the winder drum around its axis of rotation. The axes of rotation of the winder drums are usually horizontal. The carousel winder also has a rotary motion drive for jointly turning the winder drums about a common axis of rotation in an elliptical, preferably circular, path. The axis of rotation of the swivel drive is also usually horizontal. The winder drum drives are high speed drives (high speed) with speeds up to 800 1/min. In contrast, the rotary motion drive is low speed (low speed) with a typical speed of up to 0.1 1/min.

According to one preferred embodiment, said individual rotary drives for the winder drums are variable speed drives. Thus, these drives are either hydraulic rotary drives that can be operated in open or closed loop, or they are electric rotary drives with a synchronous or asynchronous motor, which is controlled by a frequency converter, respectively, controlled by the speed.

In order to be able to cut the finished strip as tension-free as possible, preferably directly in front of the shears and preferably also directly behind them, at least one pair of feed rollers is arranged. Thanks to these pairs of feed rollers, the tension in the finished strip can be reduced to a minimum before cutting. As a result, the reliability of the separation in the transverse direction, as well as the quality of the cut, is increased.

In addition, it is preferable that the carousel winder in the horizontal direction with respect to the shears be located in such a way that the distance at the start of winding between the shears and the drum of the carousel winder is <6 m, preferably <3 m. This distance is measured from the shear blades to the axis of rotation of the first drum winders.

Further, in the combined continuous casting and rolling plant according to the invention, it is advantageous if the carousel winder is positioned vertically relative to the shears so that the upper edge of the winder drum is in line with the finishing strip.

Both of the aforementioned embodiments, each alone and especially in combination with each other, are very preferred. First, the specified distance between the shear and the winder drum is much shorter than in other coiler concepts, where this distance can be > 14 m. the strip should no longer be guided under the rolling line.

The carousel winder can be made particularly compact if the first rotary drive is connected to the first winder drum via a shaft, and the second rotary drive is connected to the second winder drum via a hollow shaft, said hollow shaft enclosing said shaft at least in some areas.

Preferably, the first rotary drive is connected to a shaft via a first gearbox, and said shaft is connected to the first winder drum via a third gearbox.

It is also preferable that the second rotary drive is connected to the hollow shaft via a second gearbox, and the hollow shaft is connected to the second winder drum via a third gearbox.

The method problem according to the invention is solved by means of a continuous operation method of a combined continuous casting and rolling plant for producing a hot-rolled finishing strip according to independent claim 9. Preferred embodiments are the subject of the dependent claims.

Specifically, this solution is achieved by a method for continuous operation of a combined continuous casting and rolling plant for producing a hot-rolled finishing strip with a thickness of ≤1 mm, preferably ≤0.8 mm, particularly preferably ≤0.6 mm, which includes the following method steps:

- continuous casting of an endless cast billet with a cross-section of a slab or a thin slab from molten steel in a continuous casting machine with an arcuate billet guide,

- rough rolling of a cast billet into an endless rough strip in a multi-stand rough line of rolling stands,

- finishing rolling of a rough strip into an endless finished strip in a multi-stand finishing line of stands,

- cooling of the endless finishing strip to the coiling temperature in the cooling section,

- winding an endless finishing strip in a carousel winder with the first and second winder drums,

moreover, this method is improved in the direction that the endless finishing strip is divided in the transverse direction by means of shears into the leading and subsequent sections of the finishing strip, the leading section of the finishing strip is wound on the first reel of the winder, and the subsequent section of the finishing strip is wound on the second drum winders.

Preferably, the upper edge of each winder drum at the beginning of the winding (ie during the so-called winding up) is in line with the finishing strip. This makes it possible to avoid changing the direction of the finishing strip.

In addition, it is preferable that the drums of the carousel winder rotate during winding in an elliptical, preferably in a circular path. Typically, the first reel drum during winding from the 180° position rotates clockwise in the 0° direction, while the second reel drum from the 0° position rotates clockwise in the 180° direction.

The carousel winder is particularly suitable for winding very thin and very fast moving finished strips, so that the finished strip thickness is preferably <1 mm, preferably <0.8 mm, particularly preferably ≤0.6 mm. With a thickness of <1 mm, it is preferable that the transport speed of the finishing strip is >8.4 m/s; with a thickness of <0.8 mm, the transport speed is preferably >10.5 m/s; with a thickness of ≤0.6 mm, a particularly preferred conveying speed is ≥14 m/s.

Brief description of the drawings

The above described features, features and advantages of the present invention, as well as the manner in which they are achieved, will become clearer and more clearly understood from the following description of the exemplary embodiment, which is explained in more detail with the help of the drawings. The drawings show the following.

Fig. 1 diagram of a combined continuous casting and rolling plant with a carousel winder,

Fig. 2 is a detailed view of the carousel winder of FIG. 1, and

Fig. 3a, Fig. 3b is a front and top view of a carousel winder with its drives.

Description of options

On FIG. 1 shows a diagram of an Arvedi ESP type combined continuous casting and rolling plant with a carousel winder 18. During operation of the combined continuous casting and rolling plant, the casting distributor 2 of the continuous casting plant 1 is loaded with liquid steel. In the mold 3, a partially solidified cast billet 4 with a hardened shell of the billet is formed from the steel melt. The cast billet 4 is continuously drawn out of the mold 3 and additionally cooled in the arc-shaped billet guide, so that the cast billet 4 finally enters the roughing line 5 of the rolling stands in a fully solidified state. In a three-stand roughing line of rolling stands, a cast billet 4 with a cross-section of a slab or thin slab is pre-rolled into a rough strip. The uncut rough strip is then heated by means of several inductors of the induction furnace 8 and, in the heated state, immediately before the finishing line 11 of the stands, is descaled. By heating and subsequent descaling of the roughing strip, a good descaling result is achieved. The rough strip, cleaned of scale, enters the five-stand finishing line 11 stands and there it is completely rolled into the finished strip. This finishing strip usually has a thickness between 0.6 and 6 mm.

In particular, when producing very thin finishing strip <1 mm, <0.8 mm or even ≤0.6 mm with existing hot strip coilers, problems can arise, since the finishing strip moves very quickly on the roller table 14 and, in in particular, after cutting the finishing strip in the transverse direction with the shears 16 in the area behind the shears 16, it tends to tear off, respectively, to fly off. The present invention effectively counteracts this problem, namely through the use of a carousel winder 18.

After finishing rolling in the finishing line 11 of the stands, the finishing strip in the cooling section 13 is cooled to the coiling temperature and is cut with scissors 16 into segments equal to the length of the unfolded roll.

Shown in FIG. 2 is an enlarged view of the outlet area of the combined continuous casting and rolling plant of FIG. 1. In order to be able to cut the finished strip coming through the roller table 14 from the cooling section as far as possible without tension, there are a pair of feed rollers 15, 17 in front of the shears 19 and after the shears 19. By means of these pairs of feed rollers, tension or compression can be applied to the finished strip. To do this, at least one roller of a pair of feed rollers is made with the possibility of a drive and can be pressed against the other roller of this pair of feed rollers by means of a pressure device. Both in front of the first pair 15 of the feed rollers, between the first pair of 15 feed rollers and the shears 16, between the shears 16 and the second pair of feed rollers 17, and between the second pair of 17 feed rollers and the carousel winder 18, there are guide partitions 19 that prevent the separation of the finishing strip from roller table 14.

Unlike "conventional" winders, the drums of the carousel winder are located in the vertical direction at the beginning of the winding on the line of passage 30 of the finishing strip. Due to this, there is no need to change the direction of the finishing strip in the direction obliquely under the roller table 14.

When winding the finishing strip onto the first winder drum 21a, the finishing strip is pressed against the winder drum by means of four (usually three, four or five) guide rollers located along the perimeter of the winder drum 21a. The guide rollers can be pressed by means of hydraulic, pneumatic or electromechanical actuators with controlled or adjustable pressure, respectively, force. After winding up the finishing strip, the winder drums 21a, 21b, with the help of the winder shown in FIG. 3a, Fig. 3b of the rotary drive 27 are rotated along a circular path 29. In this case, the first winder drum 21a rotates around the horizontal axis 28 of rotation back, and the second drum 21b of the winder rotates around the same axis 28 of rotation forward. The terms “front” and “back” refer to the direction of material flow in the finishing strip.

Shortly before the winder reaches its final weight, the finishing strip is divided transversely by the shears 16 into the front and subsequent sections of the finishing strip. The section of the finishing strip leading in front - as shown in Fig. 2 - is wound on the second drum 21b of the winder. The second winder drum 21b is "behind" the first winder drum 21a. The subsequent section of the finishing strip, on the contrary, is wound on the first winder drum 21a, which is "in front" of the second winder drum 21b, and its drum is in the vertical direction in the line of the finishing strip.

On FIG. 3a and Fig. 3b shows the drives, gearboxes and drums of the rotary winder of FIG. 1 and FIG. 2. Specifically, the carousel winder 18 has three drives, namely one rotary drive 20a, 20b each with variable speed for the first and second winder drums 21a, 21b, and a rotary motion drive 27 for rotating the winder drums 21a, 21b along a circular path 29. Both rotary actuators 20a, 20b are high-speed with a maximum rotation speed of 800 1/min; the slewing drive 27, on the other hand, is low-speed with a maximum speed of up to 0.1 1/min.

On FIG. 3b also shows the torque flows from the rotary drives 20a, 20b to the winder drums 21a, 21b. The torque of the first rotary drive 20a is transmitted through the first gearbox 24a to the shaft 25, and from the shaft 25 through the third gearbox 24c is transmitted to the first winder drum 21a. The torque of the second rotary drive 20b is transmitted through the second gearbox 24b to the hollow shaft 26, and from the hollow shaft 26 through the third gearbox 24c is transmitted to the second winder drum 21b. The hollow shaft 26 encloses the shaft 25 at least in some areas in the area between the second gearbox 24b and the third gearbox 24c.

Using the combined continuous casting and rolling plant according to the invention and the method according to the invention for operating the combined continuous casting and rolling plant, thin finished steel strips with a thickness of ≤1 mm, preferably ≤0.8 mm, particularly preferably ≤0.6 can be produced very reliably. mm in industrial mass production. Due to the small distance between the shear and the carousel coiler, said combined continuous casting and rolling plant can be designed to be more compact than comparable plants typically with three underfloor coilers. Due to the fact that the winding of the finishing strip is always carried out in a certain position (namely, by means of the front winder drum), the finishing strip has a more uniform temperature, which favorably affects the quality. Finally, the use of a carousel coiler eliminates the change in the direction of the finishing strip towards the underfloor coilers, thereby further increasing reliability.

The invention is furthermore not limited to combined continuous casting and rolling plants of the Arvedi ESP type, but can also be used with advantage in CSP plants from SMS, respectively, in QSP or DUE plants from Danieli.

Although the present invention has been described in detail and illustrated with preferred embodiments, the present invention is not limited to the disclosed examples, and other variations may be derived by one skilled in the art without departing from the protection scope of the present invention.

List of reference symbols

1 continuous casting plant

2 filling distributor

3 mold

4 cast billet

5 rough rolling line

6 measuring devices for determining the temperature profile, width and thickness of the rough strip

7 gateway device for input and output

8 induction oven

9 descaling device

11 finishing rolling line

12 measuring devices for determining the temperature profile, width, thickness and flatness of the finishing strip

13 cooling section

14 roller table

15, 17 a pair of drive rollers

16 scissors

18 carousel winder

19 baffle

20a, 20b rotary drive

21a, 21b winder drum

22a, 22b axis of rotation of the winder drum

23a…23h guide roller

24a…24c reducer

25 shaft

26 hollow shaft

27 rotary drive

28 axis of rotation

29 trajectory

30 finishing line

31 carousel gearbox

32 carousel swivel support

Claims (25)

1. Combined continuous casting and rolling plant for producing hot-rolled finishing strip with a thickness of less than or equal to 1 mm, and this combined continuous casting and rolling plant contains: - installation (1) for continuous casting with an arcuate billet guide for continuous casting of a cast billet (4) with a cross section of a slab or thin slab of steel melt, - multi-stand roughing line (5) of rolling stands for rough rolling of a cast billet (4) into a rough strip, - a multi-stand finishing line (11) of stands for finishing rolling a rough strip into a finished strip, - cooling section (13) for cooling the finishing strip, - shears (16) for dividing the finishing strip in the transverse direction, and these shears (16) are located in the direction of the material flow behind the cooling section (13), at the same time, in the direction of material flow behind the shears (16), a carousel winder (18) is installed for winding the finishing strip on the first and second winder drums (21a, 21b), each drum (21a, 21b) of the winder has a separate rotary drive (20a, 20b) to rotate the drum (21a, 21b) of the winder about its axis of rotation (22a, 22b), and the carousel winder (18) has a rotary motion drive for joint rotation of the drums (21a, 21b) of the winder around a common axis of rotation (28) in an elliptical , preferably along a circular path (29), characterized in that the individual rotary drives (20a, 20b) are variable speed drives. 2. Combined continuous casting and rolling plant according to claim 1, characterized in that immediately before the shears (16) and preferably also immediately after the shears (16) there is a pair (15, 17) of feed rollers. 3. Combined continuous casting and rolling plant according to claim 1 or 2, characterized in that the carousel winder (18) is located in the horizontal direction relative to the shears (16) in such a way that the distance at the start of winding between the shears and the drum of the carousel winder is less than 6 m, preferably less than 3 m. 4. Combined installation of continuous casting and rolling according to any one of paragraphs. 1-3, characterized in that the carousel winder (18) is located in the vertical direction relative to the shears (16) in such a way that the upper edge of the drum (21a) of the winder is on the line (30) of the finishing strip. 5. Combined installation of continuous casting and rolling according to any one of paragraphs. 1-4, characterized in that the first rotational drive (20a) through the shaft (25) is connected to the first drum (21a) of the winder, and the second rotational drive (20b) through the hollow shaft (26) is connected to the second drum (21b) of the winder, moreover, this hollow shaft (26) encloses the shaft (25) at least in sections. 6. Combined continuous casting and rolling plant according to claim 5, characterized in that the first rotary drive (20a) is connected to the shaft (25) via the first gearbox (24a), and the shaft (25) is connected to the first one via the third gearbox (24c). drum (21a) of the winder. 7. Combined continuous casting and rolling plant according to claim 5 or 6, characterized in that the second rotary drive (20b) is connected to the hollow shaft (26) via the second gearbox (24b) and the hollow shaft (26) is connected to the hollow shaft (26) via the third gearbox (24c). ) is connected to the second drum (21b) of the winder. 8. A method for manufacturing a hot-rolled finishing strip with a thickness of less than or equal to 1 mm at a combined continuous casting and rolling plant, which includes the following steps: - continuous casting of an endless cast billet (4) with a cross-section of a slab or a thin slab of molten steel in a continuous casting machine (1) with an arcuate billet guide, - rough rolling of a cast billet into an endless rough strip in a multi-stand rough line (5) of rolling stands, - finishing rolling of a rough strip into an endless finished strip in a multi-stand finishing line (11) stands, - cooling the endless finishing strip to the coiling temperature in the cooling section (13), - winding an endless finishing strip in a carousel winder (18) with the first and second drums (21a, 21b) of the winder, moreover, the endless finishing strip is divided in the transverse direction by means of scissors (16) into the leading and subsequent sections of the finishing strip, and the leading section of the finishing strip is wound on the first reel (21a) of the winder, and the subsequent section of the finishing strip is wound on the second reel (21b ) of the winder, wherein each drum (21a, 21b) of the winder, respectively, is rotated around its rotation axis (22a, 22b) by means of a separate rotational drive (20a, 20b) with variable rotation speed. 9. The method according to claim 8, characterized in that the upper edge of each winder drum (21a, 21b) is on the line (30) of the finishing strip during winding. 10. Method according to claim 8 or 9, characterized in that both winder drums (21a, 21b) are rotated during winding along an elliptical, preferably circular path (29). 11. The method according to any one of paragraphs. 8-10, characterized in that the thickness of the finishing strip is less than 1 mm, preferably less than 0.8 mm, particularly preferably 0.6 mm or less. 12. Method according to claim 11, characterized in that the conveying speed of the finishing strip is more than 8.4 m/s, preferably more than 10.5 m/s, particularly preferably 14 m/s or more.

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