Apparatus for producing a molten seal in a continuous casting furnace

Abstract

A seal for a continuous casting furnace having a melting chamber with a mold therein for producing a metal cast includes a passage between the melting chamber and external atmosphere. As the cast moves through the passage, the cast outer surface and the passage inner surface define therebetween a reservoir for containing liquid glass or other molten material to prevent the external atmosphere from entering the melting chamber. Particulate material fed into the reservoir is melted by heat from the cast to form the molten material. The molten material coats the cast as it moves through the passage and solidifies to form a coating to protect the hot cast from reacting with the external atmosphere. Preferably, the mold has an inner surface with a cross-sectional shape to define a cross-sectional shape of the cast outer surface whereby these cross-sectional shapes are substantially the same as a cross-sectional shape of the passage inner surface.

1 . A casting furnace for manufacturing a metal cast, the furnace comprising: 
 an interior chamber having a sidewall;    a passage wall having an inner periphery which defines a passage extending through the sidewall of the interior chamber for communicating with the interior chamber and with atmosphere external to the interior chamber;    a circumferential space within the passage;    a metal cast pathway extending from the interior chamber through the passage and adapted for moving the metal cast from the interior chamber to the external atmosphere;    a source of solid particulate coating material;    a heat source for melting the particulate coating material to form molten coating material within the circumferential space; and    a dispenser for dispensing the solid particulate coating material in a solid state from the source directly into the circumferential space adjacent the pathway.    
   
   
       2 . The furnace of  claim 1  in combination with the metal cast; and wherein the heat source comprises heat radiating from the metal cast.  
   
   
       3 . The combination of  claim 2  wherein the heat radiating from the metal cast is sufficient for melting the particulate coating material.  
   
   
       4 . The furnace of  claim 1  wherein the furnace is free of a melting chamber for melting the solid coating material at a location external to the interior chamber.  
   
   
       5 . The furnace of  claim 4  wherein the circumferential space is the only location of the furnace for melting the particulate material.  
   
   
       6 . The furnace of  claim 1  wherein the passage has a transverse cross-sectional shape adapted to be substantially the same as and larger than a transverse cross-sectional shape of the metal cast.  
   
   
       7 . The furnace of  claim 1  further comprising a continuous casting mold in the interior chamber; an inner surface on the mold defining a transverse cross-sectional shape adapted to define a transverse cross-sectional shape of the metal cast; and a section of the inner periphery of the passage wall defining a narrowest portion of the passage having a transverse cross-sectional shape substantially the same as and larger than the transverse cross-sectional shape defined by the inner surface of the mold.  
   
   
       8 . The furnace of  claim 1  in combination with the metal cast; and further comprising a molten bath at least a portion of which is disposed in the circumferential space; and wherein the metal cast has an outer periphery; and the circumferential space is defined between the outer periphery of the metal cast and the inner periphery of the passage wall.  
   
   
       9 . The combination of  claim 8  wherein the molten bath is in contact with the outer periphery of the metal cast to form a protective barrier thereon as the metal cast moves from the interior chamber to the external atmosphere.  
   
   
       10 . The combination of  claim 9  wherein the passage wall comprises an inwardly projecting annular flange which defines a narrower portion of the passage; the passage wall above the flange defines a wider portion of the passage; and the inner periphery of the flange is spaced from and adjacent the outer periphery of the metal cast as it moves through the passage to define a thickness of the protective barrier.  
   
   
       11 . A casting furnace for manufacturing a metal cast, the furnace comprising: 
 an interior chamber having a sidewall;    a passage wall having an inner periphery which defines a passage extending through the sidewall of the interior chamber for communicating with the interior chamber and with atmosphere external to the interior chamber;    a metal cast pathway extending from the interior chamber through the passage and adapted for moving the metal cast from the interior chamber to the external atmosphere;    a molten bath bounding the pathway along at least a portion of the passage and adapted to prevent the external atmosphere from entering the interior chamber;    a source of particulate coating material;    a dispenser for dispensing the particulate coating material in a solid state from the source to adjacent the molten bath; and    a heat source adjacent the molten bath for melting the particulate coating material to form molten coating material for the molten bath.    
   
   
       12 . The furnace of  claim 11  further comprising an exit end on the dispenser adjacent the metal cast pathway and above the molten bath.  
   
   
       13 . The furnace of  claim 12  in combination with the metal cast; and further comprising an outer periphery on the metal cast; and wherein the exit end is adjacent the outer periphery of the metal cast when moving through the passage via the pathway.  
   
   
       14 . The furnace of  claim 11  further comprising an exit end on the dispenser adjacent the inner periphery of the passage wall.  
   
   
       15 . The furnace of  claim 11  further comprising an exit end on the dispenser adjacent the passage wall and above the molten bath.  
   
   
       16 . The furnace of  claim 15  wherein the passage wall has an upper end; and the exit end of the dispenser is adjacent the upper end of the passage wall.  
   
   
       17 . The furnace of  claim 11  further comprising a continuous casting mold in the interior chamber adapted for producing the metal cast; and an exit end on the dispenser below the mold.  
   
   
       18 . The furnace of  claim 11  wherein the furnace is free of a melting chamber for melting the solid coating material at a location external to the interior chamber.  
   
   
       19 . The furnace of  claim 11  in combination with the metal cast; and wherein the heat source comprises heat radiating from the metal cast.  
   
   
       20 . The combination of  claim 19  wherein the heat radiating from the metal cast is sufficient for melting the particulate coating material.