Device for continous or semi-continous casting of metal material

Abstract

The present invention relates to a device for continuous or semi-continuous casting of a metal material. The device comprises a first arrangement comprising a coil ( 7 ) having an extension around the casting mould ( 2 ) in an area, which is arranged to comprise molten metal material. The coil ( 7 ) is arranged to be fed with alternating current such that a varying magnetic field is generated and is applied to the molten metal material in the casting mould ( 2 ). The device also comprises a second arrangement comprising at least two magnetic poles ( 8 ), which are provided at opposite sides of the casting mould ( 2 ). The poles ( 8 ) are arranged to supply a static or periodic low-frequency magnetic field to the molten metal material in the casting area. The poles ( 8 ) comprise at least a portion ( 11 ) which comprises a plurality of material layers which are electrically insulated from each other.

1 . A device for continuous or semi-continuous casting of a metal material, wherein the device comprises a casting mould ( 2 ) which allows casting of a metal material to a desired shape, means ( 6 ) for supplying a molten metal material to the casting mould ( 2 ), a first arrangement comprising a coil ( 7 ) having an extension around the casting mould ( 2 ) in a moulding area arranged to comprise molten metal material and which coil ( 7 ) is arranged to be fed with an alternating current in such a way that a varying magnetic field is generated and is applied to the molten metal material in the casting mould ( 2 ), and a second arrangement comprising at least two magnetic poles ( 8 ) which are provided at opposite sides of the casting mould ( 2 ) and which poles ( 8 ) are arranged to supply a static or periodic low-frequency magnetic field to the molten metal material in the moulding area, characterised in that said poles ( 8 ) comprises at least a portion ( 11 ) which comprises a plurality of material layers which are electrically insulated from each other.  
     
     
         2 . A device according to  claim 1 , characterised in that said material layers comprise an electric steel.  
     
     
         3 . A device according to  claim 2 , characterised in that said material layers comprise a siliconized electric steel having a high resistivity.  
     
     
         4 . A device according to any one of the preceding claims, characterised in that said material layers have a thickness in the range of 0.25-0.5 mm.  
     
     
         5 . A device according to any one of the preceding claims, characterised in that said portion ( 11 ) of the pole ( 8 ) comprises a part of the pole ( 8 ) which is located nearest the coil ( 7 ) of the first arrangement.  
     
     
         6 . A device according to any one of the preceding claims, characterised in that each of said material layers comprises plate shaped elements having two substantially plane lateral surfaces which have an extension in a plane substantially perpendicular to the direction of current (I) in the most closely located part of the coil ( 7 ).  
     
     
         7 . A device according to any one of the preceding claims, characterised in that the coil ( 7 ) of the first arrangement and at least one of the poles ( 8 ) of the second arrangement are provided in contact with each other.  
     
     
         8 . A device according to  claim 7 , characterised in that at least one pole ( 8 ) comprises a recess ( 12 ) arranged to receive said coil ( 7 ).  
     
     
         9 . A device according to any one of the preceding claims, characterised in that the second arrangement comprises at each of said opposite sides at least one pole ( 8 ), which poles ( 8 ) have an extension along substantially the whole width of the casting mould and a yoke ( 9 ) which connects said poles ( 8 ) to each other.  
     
     
         10 . A device according to any one of the claims  1 - 8 , characterised in that the second arrangement comprises at each of said opposite sides at least two poles ( 8 ) and yokes ( 9 ) connecting the poles ( 8 ), which are located at the same side of the casting mould ( 2 ), to each other.  
     
     
         11 . A device according to  claim 10 , characterised in that said poles ( 8 ) which are provided at the same side of the casting mould ( 2 ) have an extension along substantially the whole width of the casting mould ( 2 ) and are provided at different levels in relation to the casting mould ( 2 ).  
     
     
         12 . A device according to any one of the preceding claims, characterised in that the second arrangement comprises coils ( 10 ) extending around each of said poles ( 8 ) which are arranged to be fed with a direct current or a low-frequency alternating current.  
     
     
         13 . A device according to any one of the preceding claims, characterised in that said means for supplying the molten metal material comprises a tubular member ( 6 ) which supplies the molten metal material into the casting mould.  
     
     
         14 . A device according to any one of the preceding claims, characterised in that the cast metal material comprises steel.  
     
     
         15 . A use of a device according to any one of the preceding claims  1 - 14  for continuous or semi-continuous casting of a metal material.