Stirring-roller for a continuous slab-casting machine

Abstract

A split stirring roll including two half-rolls aligned at a distance from one another, each incorporating a polyphase linear inductor mounted fixedly a short distance from outer tubular bodies of each half-roll to arrange between them an annular space for circulation of a cooling fluid; each inductor can generate a traveling magnetic field sliding along the width of a cast slab. The two half-rolls are mounted externally in end rolling bearings and internally in a common intermediate rolling bearing attached between them, the inductors including narrowed-diameter hollow terminal portions to rest in the three rolling bearings and communicate with a cooling circuit including the annular spaces. The split stirring roll is configured for continuous casting of extra-wide slabs and can form a preferred tool for controlled electromagnetic stirring of molten metal for optimized exchange of material between a top and bottom of a casting machine.

1 - 7 . (canceled) 
     
     
         8 . A split stirring roll for a machine for continuous casting of large cross section flat products or a slab, comprising:
 an element in axial rotation configured to come into rolling contact with a large surface of the cast slab, the element including at least one cylindrical tubular body held at its ends by two spindles, of generally frustoconical shape, small bases of which rest on two end rolling bearings attached to rigid structures of the frame of the casting machine;   an electromagnetic stirring equipment filling up an internal free space of the tubular body, coaxially with the tubular body and at a short distance to arrange an annular space between them;   a cooling circuit, including the annular space, to circulate a cooling liquid to secure a heat level of the tubular body in contact with the slab and of the electromagnetic stirring equipment; and   electric connection terminals to ensure electric connection of an item of the electromagnetic stirring equipment with an external electricity supply,   wherein the electromagnetic stirring equipment includes two polyphase linear inductors placed end-to-end and aligned, electrically independent and each capable of generating a travelling magnetic field sliding independently of the other.   
     
     
         9 . A split stirring roll according to  claim 8 , wherein the item of electromagnetic stirring equipment includes a magnetic core that is common to the two inductors that form it. 
     
     
         10 . A split stirring roll according to  claim 8 , wherein each of the two inductors forming the item of electromagnetic stirring equipment includes its own magnetic core distinct from that of the other inductor. 
     
     
         11 . A split stirring roll according to  claim 8 , wherein the element in axial rotation, configured to come into rolling contact with the surface of the cast slab on which it is resting, includes two distinct aligned cylindrical tubular bodies and includes a third intermediate rolling bearing between the two other end rolling bearings and delimiting with the two other end roller bearings, two half stirring rolls situated on either side of the intermediate bearing and each formed by one of the two tubular bodies, each tubular body being held at its ends by two spindles of generally frustoconical shape, one of small bases of which rests in an end rolling bearing and the other rests in the intermediate rolling bearing. 
     
     
         12 . A split stirring roll according to  claim 10 , wherein the element in axial rotation, configured to come into rolling contact with the surface of the cast slab on which it is resting, includes two distinct aligned cylindrical tubular bodies and includes a third intermediate rolling bearing between the two other end rolling bearings and delimiting with the two other end roller bearings, two half stirring rolls situated on either side of the intermediate bearing and each formed by one of the two tubular bodies, each tubular body being held at its ends by two spindles of generally frustoconical shape, one of small bases of which rests in an end rolling bearing and the other rests in the intermediate rolling bearing. 
     
     
         13 . A split stirring roll according to  claim 12 , wherein the intermediate rolling bearing is situated in a middle of a width of the slab. 
     
     
         14 . A caster for continuous casting of metal slabs fitted with stirring rolls, wherein at least two of the stirring rolls are split stirring rolls according to  claim 8 . 
     
     
         15 . A caster for continuous casting of metal slabs according to  claim 14 , wherein the two split stirring rolls are placed facing one another, either on either side of large faces of the cast slab, or one above the other on one and a same large face, and wherein the two polyphase linear inductors which each incorporates are connected to electricity supplies to generate travelling magnetic fields which slide in opposite directions on the two inductors of one and a same split stirring roll and in a same direction on the inductors facing one another in distinct split stirring rolls.