Method and casting/rolling mill for producing steel strips

Abstract

The invention relates to a method and a casting/rolling mill for producing steel strips ( 1 ), in particular stainless steel strips, based on the allocation of a conventional strip rolling train ( 4 ) to a high-technology continuous casting installation ( 2 ). To achieve an improved coupling of a continuous casting installation ( 2 ) to a hot-rolling train ( 4 ), the invention provides different combinations for an interface between the continuous casting installation ( 2 ) and the hot-rolling train ( 4 ).

1 . Process for producing steel strip ( 1 ), especially high-grade steel strip, by casting and subsequent rolling in a hot wide strip mill ( 4 ), at whose inlet continuously cast thick slabs (about 120 mm to 400 mm) are introduced from a reheating furnace ( 6 ) in front of the hot wide strip mill ( 4 ), wherein continuously cast thin labs (about 30 mm to 70 mm) and continuously cast medium slabs (about 70 mm to 120 mm) are introduced into rolling mills ( 3 ) intended for continuously cast thick slabs (about 120 mm to 400 mm) after (with respect to the rolling direction ( 3   a )) reheating furnaces ( 6 ) consisting of walking-beam furnaces ( 11 ).  
   
   
       2 . Process in accordance with  claim 1 , wherein when a thin slab enters the roughing train and/or the finish rolling train ( 10   a ;  10   b ), its temperature is the same as or well below or above that of a medium slab on entrance into the roughing train and/or the finish rolling train ( 10   a ;  10   b ), or the thickness of the thin slab is the same as or below or above the thickness of a medium slab on entrance into the roughing train and/or finish rolling train ( 10   a ;  10   b ).  
   
   
       3 . Continuous casting and rolling mill for producing steel strip ( 1 ), especially high-grade steel strip, with a continuous casting machine ( 2 ) and a cutting device ( 5 ), which is followed by a hot wide strip mill ( 4 ), before whose inlet for thick slabs (about 120 mm to 400 mm) a reheating furnace ( 6 ) is provided, and in the further course of the rolling train ( 3 ), edge smoothing rolls, descaling equipment, coiling equipment and the like are provided, and in the further course of the rolling train, edge smoothing rolls, descaling equipment, coiling equipment and the like are provided, wherein the connection of the continuous casting machine ( 2 ) with the hot strip mill ( 4 ) consists of a shear ( 5 ) installed at the outlet ( 2   a ) of the continuous casting machine ( 2 ), a tunnel furnace ( 6 ), and a parallel or swivel ferry ( 7   a ;  7   b ) or, in its place, a coil box ( 9 ).  
   
   
       4 . Continuous casting and rolling mill in accordance with  claim 3 , wherein an in-line mill ( 8 ) is provided within the continuous casting machine ( 2 ), followed by the shear ( 5 ), the tunnel furnace ( 6 ), and the coil box ( 9 ) and a coil handling system ( 9   a ), which are connected with the hot strip mill ( 4 ).  
   
   
       5 . Continuous casting and rolling mill in accordance with  claim 3 , wherein two or more continuous casting machines ( 2 ) with a parallel course of the casting strands ( 2   b ), each of which passes through its own shear ( 5 ) and tunnel furnace ( 6 ), are connected at the tunnel furnace outlet ( 6   a ) to the pass line ( 3 ) of the roughing and finish rolling train ( 10   a ;  10   b ) by means of a parallel ferr y ( 7   a ).  
   
   
       6 . Continuous casting and rolling mill in accordance with  claim 5 , wherein a tunnel furnace parallel ferry ( 7   a ) can be moved back and forth between the casting strands ( 2   b ).  
   
   
       7 . Continuous casting and rolling mill in accordance with  claim 3 , wherein one or more walking-beam furnaces ( 11 ) are installed in the pass line ( 3 ) after the tunnel furnace parallel ferry ( 7   a ) and before the entrance of the strip into the roughing and finish rolling trains ( 10   a ;  10   b ).  
   
   
       8 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to the pass line ( 3 ), at least the continuous casting machine ( 2 ), the shear ( 5 ), the tunnel furnace ( 6 ), and the parallel ferry ( 7   a ) are installed in a rear parallel section ( 12 ), and at least the one or more walking-beam furnaces ( 11 ), a roughing train ( 10   a ), the parallel ferry ( 7   a ), and the finish rolling train ( 10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in a front parallel section ( 13 ).  
   
   
       9 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to the pass line ( 3 ), at least the walking-beam furnaces ( 11 ), the parallel ferry ( 7   a ), roughing and finish rolling trains ( 10   a ;  10   b ), a finishing stand ( 14 ) or a Steckel mill, and a strip coiler ( 16 ) are installed in succession in a rear parallel section ( 12 ), and at least the continuous casting machine ( 2 ), the tunnel furnace ( 6 ), and the parallel ferry ( 7   a ) are installed in a front parallel section ( 13 ).  
   
   
       10 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to the pass line ( 3 ), at least the continuous casting machine ( 2 ) with a casting strand ( 2   b ) running in the same or opposite direction to the rolling direction ( 3   a ), the tunnel furnace ( 6 ) and the parallel ferry ( 7   a ) are installed in a rear parallel section ( 12 ), and at least the one or more walking-beam furnaces ( 11 ), roughing and finish rolling trains ( 10   a ;  10   b ), the parallel ferry ( 7   a ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in a front parallel section ( 13 ).  
   
   
       11 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel casting strands ( 2   b ) of two continuous casting machines ( 2 ) installed some distance apart, each of which is followed by the shear ( 5 ) and the tunnel furnace ( 6 ), a pass line ( 3 ) is centrally arranged between the casting strands ( 2   b ), on which pass line ( 3 ) at least the one or more walking-beam furnaces ( 11 ), a center swivel ferry ( 17 ), roughing and finish rolling trains ( 10   a ;  10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in succession.  
   
   
       12 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel casting strands ( 2   b ) of two continuous casting machines ( 2 ) installed some distance apart, each of which is followed by the shear ( 5 ) and the tunnel furnace ( 6 ), a pass line ( 3 ) is centrally arranged between the casting strands ( 2   b ), on which pass line ( 3 ) at least the one or more walking-beam furnaces ( 11 ), a center parallel ferry ( 7   a ), roughing and finish rolling trains ( 10   a ;  10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in succession.  
   
   
       13 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of a continuous casting machine ( 2 ) to the pass line ( 3 ) running in the same or opposite direction, at least the continuous casting machine ( 2 ), the shear ( 5 ), the tunnel furnace ( 6 ), and a first swivel ferry ( 7   b ) are installed in a rear parallel section ( 12 ), and at least the one or more walking-beam furnaces ( 11 ), a second swivel ferry ( 7   b ), which can be swung in on the first swivel ferry ( 7   b ), roughing and finish rolling trains ( 10   a ;  10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in a front parallel section ( 13 ).  
   
   
       14 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strands ( 2   b ) of two continuous casting machines ( 2 ) running in the same or opposite directions, each of which is followed by the shear ( 5 ), the tunnel furnace ( 6 ) and the swivel ferry ( 7   b ), a central pass line ( 3 ) is installed, on which one or more walking-beam furnaces ( 11 ), a roughing train ( 10   a ), a swivel ferry ( 7   b ) that can be alternately connected to one of the swivel ferries ( 7   b ) of the casting strands ( 2   b ), a finish rolling train ( 10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed.  
   
   
       15 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to a pass line ( 3 ) running in the same or opposite direction ( 18 ), at least the continuous casting machine ( 2 ) with an in-line mill ( 8 ), the shear ( 5 ), the tunnel furnace ( 6 ) and a coil box ( 9 ) that can be transversely displaced are installed in a rear parallel section ( 12 ), and at least the one or more walking-beam furnaces ( 11 ), a roughing train ( 10   a ), a coil box ( 9 ), the finish rolling train ( 10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are successively installed in the front parallel section.  
   
   
       16 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to a pass line ( 3 ) running in the same or opposite direction ( 19 ), at least the one or more walking-beam furnaces ( 11 ), a transversely displaceable coil box ( 9 ), a roughing train ( 10   a ), a finish rolling train ( 10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in a rear parallel section ( 12 ) on the pass line ( 3 ), and at least an in-line mill ( 8 ), the shear ( 5 ), the tunnel furnace ( 6 ), and the transversely displaceable coil box ( 9 ) are installed in a front parallel section ( 13 ) on the casting strand ( 2   b ) of the continuous casting machine ( 2 ).  
   
   
       17 . Continuous casting and rolling mill in accordance with  claim 3 , wherein, in the case of parallel arrangement of the casting strand ( 2   b ) of the continuous casting machine ( 2 ) to a pass line ( 3 ) running in the same or opposite direction ( 18 ), at least an in-line mill ( 8 ), the shear ( 5 ), the tunnel furnace ( 6 ) and a station ( 20 ) for a transversely displaceable coil box ( 9 ) are installed in a rear parallel section ( 12 ) in the casting strand ( 2   b ) of the continuous casting machine ( 2 ), and at least the one or more waIking-beam furnaces ( 11 ), the roughing and finish rolling trains ( 10   a ;  10   b ), the station ( 20 ) for the transversely displaceable coil box ( 9 ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed in a front parallel section ( 13 ) of the pass line ( 13 ).  
   
   
       18 . Continuous casting and rolling mill in accordance with  claim 3 , wherein at least the one or more walking-beam furnaces ( 11 ), the roughing and finish rolling trains ( 10   a ;  10   b ), one or more stations ( 20 ) for a transversely displaceable coil box ( 9 ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed on a pass line ( 3 ), and that, before the station or stations ( 20 ) for the transversely displaceable coil boxes ( 9 ), at least the one or more casting strands ( 2   b ) of a continuous casting machine ( 2 ) run perpendicularly to the pass line ( 3 ), on each of which casting strands ( 2   b ) an in-line mill ( 8 ), the shear ( 5 ), and the tunnel furnace ( 6 ) are connected to the station ( 20 ) for the transversely displaceable coil box ( 9 ).  
   
   
       19 . Continuous casting and rolling mill in accordance with  claim 3 , wherein casting strands ( 2   b ) of a continuous casting machine ( 2 ), which run in the same or opposite directions, are installed perpendicularly to a pass line ( 3 ), on which at least the one or more walking-beam furnaces ( 11 ), a roughing train ( 10   a ), one or more stations ( 20 ) for a transversely displaceable coil box ( 9 ), a finish rolling train ( 10   b ) a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed, and that at least an in-line mill ( 8 ), the shear ( 5 ), and the tunnel furnace ( 6 ) are installed on each casting strand ( 2   b ) before the respective station ( 20 ) of the transversely displaceable coil box ( 9 )  
   
   
       20 . Continuous casting and rolling mill in accordance with  claim 3 , wherein casting strands ( 2   b ) of a continuous casting machine ( 2 ), which run in the same or opposite directions ( 18 ), are installed perpendicularly to a pass line ( 3 ), on which at least the one or more walking-beam furnaces ( 11 ), a roughing train ( 10   a ), a station ( 20 ) for a transversely displaceable coil box ( 9 ) that runs transversely to the pass line ( 3 ), a finish rolling train ( 10   b ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed, such that at least the shear ( 5 ), an in-line mill ( 8 ), and the tunnel furnace ( 6 ) are installed in each casting strand ( 2   b ) before the station ( 20 ) for the transversely displaceable coil box ( 9 ).  
   
   
       21 . Continuous casting and rolling mill in accordance with  claim 3 , wherein at least several walking-beam furnaces ( 11 ), a roughing and finish rolling train ( 10   a ,  10   b ), a station ( 20 ) for a transversely displaceable coil box ( 9 ), a finishing stand ( 14 ) or a Steckel mill ( 15 ), and a strip coiler ( 16 ) are installed on a pass line ( 3 ), and that a casting strand ( 2   b ) that runs parallel to the pass line ( 3 ) from a continuous casting machine ( 2 ) is provided at each terminal station ( 20   a ) for the transversely displaceable coil box ( 9 ), such that each casting strand ( 2   b ) has at least an in-line mill ( 8 ), the shear ( 5 ), and the tunnel furnace ( 6 ), which is connected in front of the respective terminal station ( 20   a ).  
   
   
       22 . Continuous casting and rolling mill in accordance with  claim 21 , wherein the two casting strands ( 2   b ) connected to their respective terminal stations ( 20   a ) run in opposite directions.