TWI381894B - Method and casting-rolling plant for the manufacture of hot-rolled metal strip-more preferably steel material strip with high surface quality - Google Patents

Description

Method for producing hot rolled metal strips, preferably strips of steel material with high surface quality and casting rolling equipment

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a method and a casting rolling apparatus for producing a hot rolled metal, preferably a steel strip, by casting a high surface quality slab or a flat thin material in a continuous casting method, the steel strip being in a billet thereof The strand surface is derusted, heated to the rolling temperature and finished in a multi-stand hot strip rolling line with a low strip thickness, wherein after exiting a blank and after entering a heat homogenization Before the furnace and/or after leaving a thermal homogenization furnace and before entering the hot strip rolling line, the casting blank is passed through a number of rotating nozzles for descaling and/or casting, and the billet is single-sided or The double-sided oscillation marks are completely removed; the rotating nozzles are such that the pressurized liquid is repeatedly sprayed at the same surface position with high inlet pressure each time.

A similar method is known from DE 43 28 303 C2. However, it is not based on the use of a continuous casting plate or a thin plate cross section, and the rotary wheel rust removing method is mainly applied to a rolled material, so that a special manufacturing method by continuous casting is not considered. In addition, the removal depth is not sufficient to conceal each manufacturing-related oscillating ripple except that the rust is not visible.

In addition, the undesired intense cooling of the rolled material is accomplished by a very large amount of water.

A descaling device for casting and rolling mills is known from EP 0 586 823 B1. Here, a rotatable arm with a nozzle is used as well as a plate that is recommended to remove rust and a large amount of spray water.

A first descaling device comprising a conventionally designed descaling brush and a second descaling device having a rotating nozzle is known from EP 0 625 383 B1.

A descaling device with a low water consumption rotating wheel is known from EP 0 611 610 B1, which is installed to cool the rolling material.

In addition to the application of the rotary descaling device, the invention is based on the object of providing continuous casting parameters not previously considered.

The purpose of the setting is to combine the initial design according to the invention: operating the hydraulic shock continuous casting mold with a number of different vibration curves, and performing a thorough removal of the vibration ripple by determining the optimum vibration path setting for each casting material. . This has the advantage that, in addition to the fact that the actual elimination of the vibration corrugations can now be carried out completely, at the same time, subsequent finishing rolling can be promoted to form an ultra-thin final rolling thickness equal to/less than 1.2 cm. This means that for these dimensions, finish rolling in the range of, for example, the Worthite iron crystal structure is possible.

With the development of the continuation, the present invention provides that under the same casting or rolling rolling parameters, the pressure liquid can enter the rotating nozzle with a significantly smaller pressure medium than the previously expanded pressure medium in the so-called rust removing brush. As a result, it is possible to save a pressure medium such as water with the same or better descaling effect.

According to still further features, the present invention provides that the temperature loss of the cast stock can be maintained low by controlling the pressure medium to enter the rotating nozzle at the casting or rolling stock temperature level. Due to the reduction in temperature loss of the slab or sheet material, good conditions for hot rolling and energy saving of ultra-thin finishing rolling are created.

The auxiliary casting rolling equipment, preferably a compact casting equipment (CSP), comprises: a continuous casting device for liquid metal, preferably for liquid steel; in the direction of material conveying, continuous casting system connection a hydraulic shock drive, followed by at least one blank guide, a temperature homogenizer, an oven shuttle (if applicable), a multi-machine hot strip finishing line and a coiler, A device having a rotating nozzle is further mounted between the blank guide and the temperature homogenizing furnace or between a straight drive and shear and/or between the temperature homogenizing furnace and the hot strip finishing line With these nozzles, a pressure medium is repeatedly concentrated at the same surface position with high inlet pressure each time. The result: the benefits described in this method can be created.

As is known elsewhere, several nozzles for the pressure medium are mounted above a rotating wheel. However, it is equally advantageous to provide such a nozzle system for media other than normal temperature water.

A further development of the present invention provides a plurality of rotating wheels having nozzles for pressure media mounted on the circumference of the rotating wheel, the rotating wheels being mounted in a straight line that is transverse to the path of the cast or rolled stock. As a result, previously used rust brush spray beams can be replaced individually or completely.

Finally, prior to entering the first finishing mill, the application of the rotary wheel descaling device is to provide a hot strip rolling line with seven or more finishing stands.

A casting rolling apparatus 1 (Fig. 1) is preferably composed of a CSP (Compact Steel Plant), which is composed of a continuous casting device 2, wherein a liquid metal, preferably a liquid The steel is cast from the continuous casting mold 9. The continuous casting mold 9 is provided with a hydraulic shock driver 9a (Fig. 2). In the blank release direction 11, the continuous casting mold 9 is a blank guide 3, a temperature homogenizing furnace 4, a hob 5 (if installed), and a multi-machine hot strip finishing line. 6, followed by a coiler 8 for the coiled strip 7.

Between the blank guide 3 and the temperature homogenizing furnace 4 or between a shearing machine 13 and a straightening drive 12 and/or between the temperature homogenizing furnace 4 and the hot metal strip finishing line 6 A device 14 (Fig. 4) having a rotating nozzle 15 is mounted, by which the pressure medium (mostly liquid, such as water) is repeatedly cycled at the same surface position with high inlet pressure.

According to Fig. 3, the hydraulic shock continuous casting mold 9 is moved by a number of different vibration curves 16, 17, 18, so that for each selected casting material, a different vibration path 18a can be obtained. The vibration curves 16, 17, 18 can pass different mold strokes, different casting speeds, travel speeds of different molds during the down stroke (so-called negative strips), different curve shapes (eg sinusoidal vibrations), etc. obtain. Under the same conditions, i.e., using the relative process parameters as a basis, the pressure liquid entering the rotary nozzle 15 is implemented with a significantly less pressure (pressure medium) device as compared to the previously known rust scale brush expansion pressure. At the same time, the temperature loss of the cast stock 2b can be maintained low by maintaining the temperature level of the cast or rolled stock (2b) and entering the rotary nozzle 15.

Several nozzles 15 for the pressure medium are combined on a rotating wheel 20 (Fig. 4) having a nozzle 15 for the pressure medium mounted on the circumference 20a of the rotating wheel and arranged in a cross-casting Or rolling the nozzle arrangement 21 of the blank 2b path. Advantages can also be obtained from a number of such nozzle arrangements 21, wherein nozzle liquid columns smaller than a single nozzle row 21 can be applied.

The rotary wheel rust removing device can be applied to the hot strip rolling line 6 having seven or more finishing stands 6a before the rolled strip enters the first finishing stand 6a.

1. . . Compact steelmaking equipment

2. . . Slab shape

2a. . . Thin blank shape

2b. . . Foundry billet

2c. . . Billet surface

3. . . Blank guide

4. . . Temperature homogenizer

5. . . Hearth

6‧‧‧Hot metal strip rolling line

6a‧‧‧ Finishing mill

7‧‧‧Steel strips

8‧‧‧ coiling machine

9‧‧‧Hydraulic vibration continuous casting mold

9a‧‧‧Vibration drive

10‧‧‧Vibration curve

11‧‧‧ Billet release direction

12‧‧‧ Straight drive

13‧‧‧Shearing machine

14‧‧‧Equipment with rotating nozzle

15‧‧‧Rotating nozzle

16‧‧‧Vibration curve

17‧‧‧Vibration curve

18‧‧‧Vibration curve

18a‧‧‧Vibration curve path

20‧‧‧Rotating wheel

20a‧‧‧Rotating wheel circumference

21‧‧‧Rotating wheel train

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) The detailed description of the features of the exemplary embodiments of the present invention is shown in the following drawings: Figure 1 is a perspective side view of a cast rolling compact apparatus; Figure 2 is a hydraulic pressure in a compact protective hood The continuous casting mold of the vibration driver; Fig. 3 is a plurality of block diagrams of a plurality of different vibration moving paths of the continuous casting mold; and Fig. 4 is an individual rotating wheel having nozzles disposed at the circumference of the rotating wheel.

10. . . Vibration curve

16. . . Vibration curve

17. . . Vibration curve

18. . . Vibration curve

Claims (7)

Method for producing a hot rolled metal, preferably a steel strip (7), by rolling a high surface quality slab or a flat strand (2, 2a) in a continuous casting process , wherein the strand surface (2c) is subjected to rust removal, heating to a rolling temperature, and finish rolling at a low strip thickness in a multi-machine hot strip rolling line (6), Wherein, after leaving a strand guide (3), before entering a heat homogenizing furnace (4) and/or leaving a heat homogenizing furnace (4) and entering the hot strip rolling line (6) Thereafter, through a plurality of rotating nozzles (15), the strand is free of scale and/or cast powder and thoroughly removes vibration on one or both sides of the strand surface (2c). Oscillation marks; the rotating nozzles (15) allow the pressurized liquid to be repeatedly sprayed at the same surface position with high inlet pressure each time, characterized by operating hydraulic shocks with several different vibration curves (16, 17, 18). Continuously casting the mold (9) and performing the thorough removal of the oscillation marks by measuring the vibration path (18a) optimized for each casting material. industry. The method of claim 1, wherein: under the same parameters of the casting or rolling process, the pressurized liquid system has a significantly smaller pressure medium than the pressure medium previously expanded in the so-called descaling brush Enter the rotating nozzles (15). The method of claim 1 or 2, wherein: by controlling the pressure medium to enter the rotary nozzles (15) by the temperature level of the cast or rolled strand (2b), The temperature loss of the strand (2b) can be kept low. A casting rolling apparatus (1), preferably a compact casting and rolling equipment (CSP), comprising: a strand casting device for liquid metal, preferably for liquid steel ( 2) The continuous casting mold (9) of the strand casting device is connected to a hydraulic vibration driver (9a) in the strand leaving direction (11) at the hydraulic vibration driver (9a) Then there is at least one strand guide (3), a temperature homogenizing furnace (4), an oven shuttle (5), and if applicable, a multi-machine hot strip finishing a wire (6) and a coiler (8), characterized in that: a device (14) having a rotary nozzle (15) is disposed on the strand guide (3) and the temperature homogenizer (4) between or between a straight drive (12) and a shearing machine (13) and/or between the temperature homogenizing furnace (4) and the hot strip finishing line (6), by means of the nozzles ( 15) The pressure medium is repeatedly concentrated at the same surface position with a high inlet pressure cycle; and several nozzles (15) for the pressure medium are mounted on a rotating wheel (20). The casting rolling apparatus of claim 4, wherein: the plurality of rotating wheels (20) having nozzles (15) for pressure medium disposed on the circumference (20a) of the rotating wheel are configured to be The route of casting or rolling the strand (2b) is in the transverse direction (21). The casting rolling apparatus according to claim 4, wherein: before entering the first finishing stand (6a), the hot strip is rolled in one of seven or more finishing stands (6a). A rotary wheel descaling device is applied to the rolling line (6). The casting rolling apparatus according to claim 5, wherein: before entering the first finishing stand (6a), there are seven or more finishing mills A rotating wheel descaling device is applied to the hot strip rolling line (6) of one of the stages (6a).