DE102013212951A1 - Casting rolling mill and method for producing metallic rolling stock - Google Patents

Abstract

The invention relates to a casting and rolling plant and a method for producing metallic rolling. Known cast rolling mills 100 of this type comprise a casting line and a rolling line offset parallel to the casting line. A sludge transport from the casting line transversely to the casting direction towards the rolling line takes place with the aid of a transverse displacement device. In order to minimize the heat losses of the furnace and to optimize the heat transfer of fuel gas in the oven on the slabs is provided according to the invention that the furnace 150, the complete transverse displacement device 130 and at least a portion of the outlet roller table 128 of the strand guide 120 and at least a portion of the inlet roller conveyor 140 for the Slabs in the rolling line with encloses. In addition, the inlet of the furnace for the slabs in the casting line and the outlet of the furnace for the slabs in the rolling line is arranged so that a front-side inlet of the slabs and a front-side outlet of the slabs from the oven is possible.

Description

The invention relates to a casting and rolling plant and a method for producing metallic rolling of carbon steel.

Such casting machines and methods are basically known in the prior art; see, for. B. the publications DE 196 81 466 . EP 1 112 128 . DE 693 16 703 . EP 1 833 623 and EP 1 940 566.

Specifically, the European patent publication EP 1 833 623 B1 a cast rolling mill for producing slabs with a mold, a mold downstream strand guide for deflecting the cast casting strand from the vertical to the horizontal, a heating furnace, a descaling device, a roughing stand, a Steckel mill, a pair of scissors, a cooling device and a reel. After passing through the heating furnace, the cast strand or slabs first pass through the roughing stand before they enter the Steckel mill. All components of the system are in one line.

The European patent EP 1 940 566 B1 discloses a thin slab caster with a tandem rolling device. Already in the strand guide a reduction in thickness of the cast strand is provided; a so-called Liquid Core Reduction LCR area. The radius for deflecting the cast strand into the horizontal is less than 2 m, the casting thickness is 25-32 mm and the casting speed is 6 to 16 m / sec.

The German publication DE 196 81 466 T1 discloses a cast roll mill for producing metallic rolling stock comprising a casting line having a mold for vertically casting a casting strand and a strand guide comprising a carpet for deflecting the casting strand from vertical to horizontal, straightening means, scissors for spreading the casting strand into slabs and having an exit roller conveyor. Parallel to the casting line, the casting rolling mill comprises a rolling line with an inlet roller table and a Steckel rolling mill for rolling the slabs of rolling stock, a Steckel rolling mill downstream cooling device and a cooling device downstream winding device. Between the casting line and the rolling line a transverse displacement device is arranged for transversely transporting the slabs from the outlet roller conveyor of the strand guide to the inlet roller conveyor of the rolling line. An oven is provided for heating the slabs during transverse transport.

The invention has the object of developing a casting and a method for producing metallic rolling material according to the manner described in the last paragraph to the effect that the heat losses during transport of the slabs from the casting line in the rolling line are further reduced.

This object is achieved by the claimed in claim 1 casting rolling. This casting and rolling plant is characterized in that the furnace includes the complete transverse displacement device and at least part of the outlet roller table of the strand guide and at least part of the inlet roller table of the rolling line and that the inlet of the furnace for the slabs in the casting line and the outlet of the furnace for the slabs is arranged in the rolling line.

The claimed embodiment of the furnace has the advantage that the slabs are secured not only during their transverse transport, but already on the outlet roller conveyor of the strand guide and on the inlet roller table of Steckel rolling against unwanted cooling, because the furnace extends over these areas. Through the arrangement of the openings of the furnace for the inlet of the slabs in the casting line and the analogous arrangement of the opening for the outlet of the slabs in the rolling line in the rolling direction, the widths of the openings or the doors in these openings substantially to the width of the Slabs are limited. This is particularly advantageous in view of the energy losses or the energy balance of the furnace compared to the design of furnace doors in the prior art, where the furnace doors extend over the entire length of a slab, because the slab is retracted transversely into the furnace.

Thus, both claimed measures serve to reduce the temperature losses of the slab and to increase the efficiency of the furnace.

The claimed cast-rolling mill is used to produce rolling stock in the form of flat steel with an annual production of less than 700,000 t per year of carbon steel. The system is characterized by a compact system layout and z. B. due to the lack of a Vorgerüstes and the high efficiency of the furnace by low investment and production costs. It is therefore particularly suitable for (new) steel producers in regions without their own flat steel production. It is used for casting slabs with widths between 700 and 1,700 mm.

According to a first embodiment of the invention it is provided that the heating gas is conducted in the oven in a flow direction which runs counter to the direction of movement of the slabs in the oven. This countercurrent principle also leads to a significant increase in efficiency of the furnace, because the slabs are kept better warm in this way.

According to a further preferred embodiment, the furnace has a further opening, which either serves as an outlet for slabs which are not to be introduced into the rolling line or acts as an inlet for slabs which are not to be supplied via the casting line of the rolling line. For this purpose, the run-out roller conveyor of the strand guide is extended beyond the transverse displacement region of the furnace through the said further opening to the outside of the furnace in the casting line.

According to a further embodiment, the roller carpet of the strand guide is formed from a plurality of segments, which are arranged one behind the other in the casting direction. In a first, downstream of the mold segment three to seven pairs of rollers are initially arranged vertically one above the other to form a vertical guide region for the cast strand. In the casting direction, five to eleven further pairs of rollers within the first segment, which are arranged in an arc shape to form a bending region for bending the casting strand out of the vertical into a casting radius between 3.5 and 6.5 m, are arranged downstream of this vertical guide region. After the bending area, which is still attributed to the first segment, followed by two to four other arc segments for further guidance of the casting strand.

The said compact design of the plant is particularly evident in its supported length of ≤ 12 m and in a low overall height of the casting rolling mill between 5 and 8 m.

The above object is further achieved by a method for producing metallic rolling stock according to claim 15. This method is characterized in that the slabs enter the front side in the casting direction in the oven and backward end face in the rolling direction from the oven. The advantages of this solution correspond to the advantages mentioned above with reference to the claimed cast rolling mill.

The casting rolling mill is planned for casting speeds between 1 and 3.5 m / min.

After leaving the furnace, the slabs run directly into the rolling stand of the Steckel mill, there are reduced in thickness in a first pass and are subsequently downstream of the rolling mill on a Steckel located there, d. H. wound up there a winding furnace Steckelwalzwerks. To increase the production efficiency of the slab is not first wound in a winding furnace located upstream of the rolling mill of the Steckel mill and cached before it enters the rolling mill of the Steckel mill.

Further advantageous embodiments of the claimed casting and the claimed method are the subject of the dependent claims.

The invention is accompanied by three figures, wherein

1 the claimed casting mill in a longitudinal section;

2 the oven with associated inlet roller table and associated outlet roller table in a plan view; and

3 the essential components of the casting line of the claimed casting rolling mill
shows.

The invention will be described in detail below with reference to the said figures in the form of embodiments. In all figures, the same technical elements are designated by the same reference numerals.

Explanation of terms used:

The term "rolling direction" corresponds to the term "casting direction"; both terms mean the same direction. However, the rolling direction is offset parallel to the casting direction.

The terms "Steckel" and "winding furnace" are synonymous.

The length of the furnace means the length in the casting or rolling direction. The width of the furnace means the extent of the furnace transverse to the casting or rolling direction.

The outlet roller table of the strand guide is basically synonymous with the inlet roller table of the furnace. Both run in the casting direction. An extension of the outlet roller conveyor of the strand guide, which extends through the oven and to the outside of the oven, also runs in the casting direction.

The outlet roller table of the furnace extends in the rolling direction and is basically synonymous with the inlet roller table of the Steckel mill.

1 shows the claimed casting rolling mill in a side view. The casting rolling mill 100 includes a casting line and a rolling line, which via a transverse displacement device 130 connected to each other. The casting line comprises a casting platform 105 , a mold 110 , a strand guide 120 , a scissors 127 and a discharge roller table of the strand guide 128 , All mentioned components of the casting line are arranged one behind the other in the casting direction in the stated order.

The casting platform typically includes a turret or ladle for handling the pans for sequence casting. It is a covert casting with ceramic components between pan and distributor (shadow tube) or between distributor and mold (dip tube) provided. The distributor is typically covered with cover powder and the mold with casting powder.

The mold 110 can be formed either of four parts, two broad sides and two narrow sides or as a frame mold. It preferably has an integrated level measurement, which for example works radiometrically or with eddy current. Advantageously, the mold, in particular if it has two narrow sides, preferably has a narrow side adjustment for format adjustment during the casting operation. The mold is positioned vertically below the casting platform. It can be formed with or without funnel on the upper Kokillenkopf. When forming a funnel mold, the crown is 10 to 60 mm at the top mold head. The exit of the mold preferably runs parallel, but in the case of a funnel mold it can also have a residual embedment <10 mm. The mold walls or mold plates are preferably formed from copper or a copper alloy with or without full or partial wear-reducing coating. The alternative to using a funnel mold is the use of a plane parallel mold. The mold is equipped with an eccentric or hydraulic oscillation drive for oscillation strokes up to 360 strokes per minute and amplitudes ≤ ± 5 mm. The mold is water-cooled with water quantities of 1,000 to 3,000 l / min / meter casting width.

The strand guide 120 consists essentially of a roll carpet with divided or undivided rolls with diameters <250 mm. The rollers may be designed as axle rollers or as pin rollers, preferably with internal cooling. A bearing cooling is intended above all for center bearings.

The roles of the roll carpet are preferably in segments 121 . 122 . 123 . 124 grouped like this in 2 is shown. The segments typically each consist of an upper frame and a lower frame, on each of which a plurality of rollers is rotatably mounted. The cast strand will, as in 2 shown, guided between the opposite roles of a segment. The upper frame and the subframe with the respective rotatably mounted rollers are by means of hydraulic cylinders 129 relative to each other adjustable or adjustable. This hydraulic segment adjustment is carried out as a black / white circuit on spacers or position-controlled with a monitoring of the forces occurring with respect to a minimum and maximum permissible force value.

In a first segment 121 , that of the mold 110 immediately following in casting direction R are, as in 2 shown, initially three to seven pairs of rolls vertically stacked. The predetermined by the mold vertical orientation of the casting strand is initially extended in this way a bit far. The said roles are closed within the first segment 121 a bending region, which extends over 5 to 11 other pairs of rolls and the cast strand continuously in a casting radius bends between 3.5 and 6.5 m. In 2 this bending region can be recognized by the horizontal lines which extend to the right from the roller pairs; These lines represent the change in the bending radius, which results successively at the individual roller pairs of the bending area. The said preconnection of three to seven pairs of rollers in a vertical arrangement in front of the bending area has the advantage that forces occurring in the bending area do not reach the mold 110 but be collected by the said pairs of rollers in a vertical arrangement.

To the first segment 121 close in casting two to four further ground segments 122 . 123 . 124 at. The supported length of the casting machine is less than 12 m. Within the strand guide no appreciable thickness reduction of the casting strand is provided by means of Liquid Core Reduction LCR. Changes in the thickness of the cast strand arise only from conventional Tapereinstellungen in parts or over the entire roll carpet in the casting direction, ie due to usual wedge settings of the segments in the casting direction to compensate for naturally occurring shrinkage of the cast strand in the casting direction due to its cooling. In addition, thickness reduction can at best occur through the use of soft reduction. Soft reduction means the active squeezing of the upper and lower strand shell in the area before the solidification of the cast strand to z. B. to avoid segregation.

Within the strand leadership 120 , in the region of the segments is preferably a regulated secondary cooling provided for cooling the strand after its exit from the mold. The cooling is typically done via spray plans or preferably via a process model. In the transition area from the circular arc guide points in the horizontal the strand guide 120 a straightening device 126 on, which consists of individual controllable and at least partially driven pairs of rollers. The controllable pairs of rollers preferably have a position and force monitoring. The straightening device 126 may be implemented as three or four roller pair unit or alternatively in segmental construction. The casting thickness of the casting strand at the exit of the straightening device 126 is between 90 mm and 120 mm. The height of the plant is between 5 and 8 m.

As in 1 shown is the strand guide 120 a scissors 127 downstream of the dicing of the cast strand in slabs of predetermined length. The width of the slabs is between 700 and 1,700 mm for the claimed casting rolling mill.

The scissors 127 is in the casting direction an outlet roller conveyor 128 downstream of the strand guide.

From the casting line just described the slabs are using a furnace 150 , For example, a Hubherdofens transported in a parallel to the casting line offset rolling line. In this respect, the scissors serve 127 and the oven 125 with a transverse displacement device contained therein 130 for final coupling of casting and rolling process.

The rolling line comprises an exit roller conveyor of the furnace 150 , which is synonymous with a Einlaufrollgang 140 in a Steckel mill 160 , In the rolling line is between the oven 150 and the Steckel mill 160 preferably a descaling device 158 arranged. The Steckel mill 160 includes upstream and downstream each a Steckel, ie a winding furnace for temporarily storing the rolling stock between the individual stitches. A predetermined odd number of passes is made to reduce the thickness of the slabs to a desired final thickness. The resulting rolling stock in the form of flat steel is after passing through the Steckel mill 160 in a cooling device 170 chilled before it is either stored as a plate or, as in 1 shown by means of a winding device 180 is wound up into a covenant.

The following is with reference to 3 the furnace according to the invention described in detail.

As in 3 can be seen, includes the furnace according to the invention 150 not just the actual area of the cross slide device 130 , which serves to transport the slabs from the casting line in the rolling line across, but also the upstream outlet roller table 128 the strand guide 120 and the downstream entrance roller table 140 the rolling line in the Steckel mill 160 , Heated or exposed to the furnace atmosphere is that part of the outlet roller table 128 the strand guide 120 which of the oven 150 spanned, also called inlet region of the furnace, and the said region of the transverse displacement device 130 (Hubherdbereich called). That of a heater, in 3 not shown, provided heating gas for the interior of the furnace is passed through an inlet in the Hubherdbereich in the interior of the furnace. From there it flows against the transport direction of the slabs to an outlet, which is preferably arranged at the beginning of the kiln inlet region transversely from the inlet for the slabs in the oven, as in 3 is shown. In this way, a countercurrent principle between slab run and heating gas, which is advantageous for the heat transfer to the slabs.

The length X2 of the transverse displacement device 130 in the casting direction, ie corresponding to the length of the part enclosed by the furnace part of the inlet roller table 140 for the Steckel mill 160 is between 15 and 35 m, corresponding to the maximum length of the slabs. The length of the inlet zone in the oven, ie the part enclosed by the furnace part of the outlet roller table 128 the strand guide 120 is in proportion to the length X2, wherein the ratio X1 / X2 <1.5, preferably about 1. The width Y1 of the oven 150 transverse to the casting direction is also in relation to the length X2 of the furnace 150 , Preferably, the ratio Y1 to X2 is 0.2 to 0.8, preferably about 0.5.

Said data for the length X2 and the ratios X1 to X2 and Y1 to X2 are chosen so as to be able to realize a roll change without casting sequence interruption.

The oven 150 according to the invention is constructed so that, as in 3 shown, the slab in the casting direction frontal frontal over the outlet roller conveyor 128 with their narrow side ahead can run into the oven. Also, the leading out of the slabs is the front side, ie with its narrow side forward backwards over the roller table 140 in the direction of the Steckel mill. The exit roller table 128 the strand guide 120 can through the oven 150 through and beyond this in the form of an exit / insertion roller table 190 be extended for the slabs, as in 3 is shown. In this case, another door in the furnace wall is in transition to said off / Einschubrollgang 190 provided. Due to the frontal and non-transverse inlet of the slabs in the oven, all the doors of the furnace at the outlets and inlets for the slabs in width to substantially the max. Width of the slabs are limited. In particular, no doors or openings need to be provided in the furnace, which insert and a Allow the slabs to run across the casting line. In this way, the temperature and energy losses of the furnace can be significantly reduced.

All roller conveyors in the oven 150 can be designed with single-sided or double-sided rollers with or without roller cooling.

LIST OF REFERENCE NUMBERS

100

 continuous casting and rolling

105

 casting platform

110

 mold

120

 strand guide

121

 first segment

122

 second segment

123

 third segment

124

 fourth segment

125

 roller carpet

126

 leveler

127

 scissors

128

 Exit roller table of the strand guide

129

 hydraulic cylinders

130

 Cross-displacement device

140

 Infeed roller table in the Steckel mill in the rolling line

150

 oven

156

 Opening in the oven

158

 Entzunderunseinrichtung

160

 Steckel mill

162

 coiler furnace

164

 coiler furnace

170

 cooling device

180

 takeup

190

 Extension / insertion roller table for slabs

210

 cast strand

R

 casting

X1

 Length of the furnace in the casting direction

X2

 Length of the transverse displacement area in the casting direction

Y1

 Width of the transverse displacement area

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19681466 [0002]
• EP 1112128 [0002]
• DE 69316703 [0002]
• EP 1833623 [0002]
• EP 1940566 [0002]
• EP 1833623 B1 [0003]
• EP 1940566 B1 [0004]
• DE 19681466 T1 [0005]

Claims (20)

Cast rolling mill ( 100 ) for producing metallic rolling stock, comprising: a casting line with a mold ( 110 ) for vertical casting of a casting strand ( 210 ) and with a strand guide ( 120 ), which a roll carpet ( 125 ) for deflecting the casting strand from the vertical to the horizontal, a straightening device ( 126 ), a scissors ( 127 ) for dividing the cast strand into slabs and an outlet roller table ( 128 ), a parallel offset to the casting line arranged rolling line with an inlet roller table ( 140 ) and with a Steckel mill ( 160 ) for rolling the slabs to the rolling stock; a transverse displacement device ( 130 ) for transversely transporting the slabs of the outlet roller table ( 128 ) of the strand guide to the inlet roller table ( 140 ) of the rolling line; and a stove ( 150 ) for heating the slabs during transverse transport, characterized in that the furnace ( 150 ) the complete transverse displacement device ( 130 ) and at least part of the exit roller table ( 128 ) of the strand guide and at least part of the inlet roller table ( 140 ) includes the rolling line; and the inlet of the furnace for the slabs in the casting line and the outlet of the furnace for the slabs in the rolling line is arranged. Cast rolling mill ( 100 ) according to claim 1, characterized in that the furnace ( 150 ) has a heating device for providing heating gas for the interior of the furnace, an inlet for supplying the heating gas into the interior of the furnace opposite to the transport direction of the slab, the inlet preferably being arranged at the end of a transverse displacement area of the furnace, and an outlet for discharging the furnace Heating gas from the furnace, wherein the outlet is preferably arranged at the beginning of the outlet roller conveyor of the strand guide transverse to the inlet for the slabs in the oven. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the length (X2) of the part of the inlet roller table ( 140 ) for the Steckel mill is between 15m and 35m. Cast rolling mill ( 100 ) according to claim 3, characterized in that the ratio of the length (X1) of the part of the outlet roller conveyor of the strand guide enclosed by the oven to the length (X2) of the transverse displacement area is less than 1.5, preferably approximately 1. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the ratio of the width (Y1) of the oven to the length of the transverse displacement area (X2) is between 0.2 and 0.8; preferably at about 0.5. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the furnace ( 150 ) another opening ( 156 ), which either serves as an outlet for slabs, which are not to be introduced into the rolling line, or acts as an inlet for slabs, which are not to be supplied via the casting line of the rolling line; and the exit roller table ( 128 ) of the strand guide over the Querverschiebebereich out through the further opening ( 156 ) is extended to outside the furnace in the casting line. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the furnace ( 150 ) is designed as Hubherdofen. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the broad side walls of the mold ( 110 ) are formed parallel to the output of the mold. Cast rolling mill ( 100 ) according to any one of the preceding claims, characterized in that the roll carpet ( 125 ) of the strand guide is formed of a plurality of segments, which are arranged in the casting direction (R) in succession; wherein in one of the mold ( 110 ) immediately following the first segment ( 121 ) 3 to 7 pairs of rollers are arranged vertically above one another to form a vertical guide region for the cast strand, and subsequently another 5 to 11 pairs of rollers within the first segment are arranged arcuately to form a bending region for bending the cast strand from the vertical into a casting radius between 3, 5 to 6.5m; and wherein the first segment 2 to 4 arc segments ( 122 . 123 . 124 ) are arranged to guide the casting strand in the casting radius between 3.5 and 6.5m. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the supported length of the casting rolling mill, measured from the casting level until the beginning of the outlet of the strand guide, is less than or equal to 12 m. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the thickness of the cast strand ( 210 ) at the end of the strand guide between 90mm and 120mm. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized that the overall height of the casting rolling mill is between 5 and 8 m. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized in that the strand guide ( 120 ) has a Softreduktionbereich before the range of solidification of the cast strand. Cast rolling mill ( 100 ) according to one of the preceding claims, characterized by a Steckel mill ( 160 ) in the casting direction (R) downstream cooling device ( 170 ) for cooling the rolling stock; and, for example, a winding device connected downstream of the cooling device in the casting direction (US Pat. 180 ) for winding the cooled rolling stock. Method for producing metal rolling, comprising the following steps: In a casting line: vertical casting of a casting strand ( 210 ); Diverting the casting strand from the vertical to the horizontal; Cutting the cast strand into slabs; Transversely transporting the slabs from the casting line into a parallel offset rolling line, wherein the slabs are heated in an oven or at least kept warm; in the rolling line: rolling and reducing the thickness of the slabs in a Steckel mill to rolling stock; characterized in that the slabs enter the front side in the casting direction in the oven and backward end face in the rolling direction of the oven. A method according to claim 15, characterized in that the casting speed is between 1 and 3.5 m / min. A method according to claim 15 or 16, characterized in that the slabs in the interior of the furnace ( 150 ) are acted upon immediately after their entry into the furnace, during their transverse transport and preferably also during their subsequent transport in the rolling direction with a heating gas, which flows against the respective transport direction of the slabs. Method according to one of claims 15 to 17, characterized in that the slabs enter after leaving the furnace directly into the rolling mill of the Steckel mill, there are reduced in thickness in a first pass and are subsequently wound on the Steckel located downstream of the rolling mill of the Steckel mill. A method according to claim 18, characterized in that the slabs are rolled in the Steckel rolling mill with at least 3 stitches to their predetermined final thickness, before being cooled as rolling stock in the form of flat steel and, for example, wound up. A method according to any one of claims 15 to 19, characterized in that the material from which the cast strand, the slabs and the rolling stock are made is carbon steel.

Images