Device for continuous casting between rolls with applied side dams

Abstract

A side dam assembly for a continuous casting apparatus for continuously casting thin steel strips between casting rolls. The side dam assembly has a side dam for bearing directly against the rolls of the casting apparatus for preventing leakage of molten metal therebetween. The side dam is attached by a pair of belts to an insulating refractory plate which is carried by a cooled panel. To allow axial motion, one of the belts is not rigidly affixed to either the insulating refractory plate or the side dam. The cooled panel is carried by a thrust plate and is urged toward the rolls by biasing elements which preferably comprise a plurality of pistons urged outwardly from the thrust plate by springs. Preferably, the biasing elements are constructed and arranged so that they are distributed over a zone of shape corresponding to that of the side dam and are capable of exerting on the side dam thrust forces independently of one another.

We claim:  
     
       1. Device for continuous casting of thin metal products between rolls, including two cooled counter-rotatory rolls, two side dams and means for supporting and applying by pressure said side dams against ends of said rolls, characterized in that said support means include: 
       (a) a thrust plate which can be moved in an axial direction (A) of said rolls and which is arranged generally perpendicular to said axial direction;  
       (b) a panel, which supports one of said side dams and which is carried by said thrust plate and is arranged facing the latter;  
       (c) at least three thrust members interposed between said thrust plate and said panel, said thrust members being distributed over a zone of shape corresponding to that of said side dam, and being capable of  exerting thrust forces on said side dam thrust forces independently of one another ;  
       (d) a support carriage for ( i ) carrying said thrust plate and , ( ii ) which can be moved in said axial direction, and which includes;  ( iii ) a means for displacing said carriage relative to said rolls for enabling a force to be exerted on said rolls;  
       ( e )  said side dam comprises  ( i )  a first plate of a thermally insulating refractory material surrounded by a first belt with said first plate of thermally insulating refractory material carried by said first belt and said plate of a thermally insulating refractory material displaceable in a direction generally parallel to an axis of one of said rolls, and  ( ii )  a second plate of a refractory material surrounded by a second belt that is operably connected to said first belt for axial movement substantially in unison with said first plate of thermally insulating refractory material and constructed and arranged such that said thrust forces are transmitted through said first plate of thermally insulating refractory material to said second plate of refractory material;    
       ( f )  wherein said first plate of a thermally insulating refractory material is disposed between said panel and said second plate of a refractory material; and    
       ( g )  wherein each said second plate is of unitary construction and bears against ends of said counter - rotatory rolls.    
     
     
       2. Device according to claim  1  wherein said side dam comprises: 
       (1) a plate of a thermally insulating refractory material surrounded by a first belt with said first belt carried by said plate for permitting displacement of said plate in a direction generally parallel to an axis of one of said rolls; and  
       (2) a plate of a hard refractory material surrounded by a second belt that is operably connected to said first belt for axial movement in unison with said insulating refractory plate and constructed and arranged such that thrust forces transmitted by said panel to said insulating refractory plate are transmitted by said insulating refractory plate to said hard refractory plate.  
     
     
       3. Device according to claim  1  wherein said means for displacing said carriage relative to said rolls comprises a thrust jack. 
     
     
       4. Device according to claim  1  further comprising a rigid chassis, a prepositioning carriage carried by said chassis and which carries said support carriage, and a screw-nut assembly in operable communication with said chassis and said prepositioning carriage for enabling said side dam to be controllably moved toward or away from said rolls. 
     
     
       5. Device according to claim  1 , characterized in that said thrust members are springs. 
     
     
       6. Device according to claim  5  wherein the stiffness of each said spring and the distribution of said springs in said zone are determined so that, for the same flexion of said springs, the thrust force which they exert on the lower part of said side dam is greater than the thrust force exerted on the upper part of said side dam. 
     
     
       7. Device according to claim  1 , characterized in that said thrust members are controlled jacks. 
     
     
       8. Device according to claim  7 , characterized in that said jacks are pressure-regulated. 
     
     
       9. Device according to claim  1  wherein said panel is designed so that the thrust force which it transmits is applied only on said side dam. 
     
     
       10. Device according to claim  9  wherein said side dam consists of a plate of hard refractory material surrounded by a metal belt to which it is connected, and said metal belt is fixed on a cooled belt surrounding a plate of thermally insulating refractory material, with said cooled belt and said insulating refractory plate constructed and arranged to allow relative movement therebetween in a direction generally parallel to an axis of one of said rolls, said cooled belt being supported by said panel, and said insulating refractory plate being constructed and arranged so that the thrust force transmitted by said panel to said insulating refractory plate is retransmitted by said insulating refractory plate only to said plate of hard refractory material. 
     
     
       11. Device according to claim  10   1 wherein said cooledfirst belt is cooled and surrounds the entire periphery of said insulating refractoryfirst plate of insulating refractory material and is not rigidly attached to said insulating refractoryfirst plate to allow relative movement between said cooled belt and said insulating refractoryfirst plate in a direction generally parallel to an axis of one of said rolls. 
     
     
       12. Device according to claim  1  wherein said counter- rotatory rolls have a casting space therebetween that is generally triangular and said at least three thrust members are distributed over a zone of triangular shape corresponding to said substantially triangular shape of said casting space.   
     
     
       13. Device according to claim  12  wherein each of said side dams are substantially triangular. 
     
     
       14. Device according to claim  13  wherein each of said side dams have a first side edge is curved and has a portion that overlaps part of one of said counter- rotatory rolls and a second side edge that is curved and has a portion that overlaps part of the other one of said counter - rotatory rolls.   
     
     
       15. Device according to claim  12  wherein said at least three thrust members comprises five spaced apart rows of pistons with each said piston urged toward said side dam by a spring. 
     
     
       16. Device according to claim  15  wherein three rows of thrust members is comprised of eleven spaced apart pistons each urging said side dam toward one of said counter- rotatory rolls.   
     
     
       17. Device according to claim  11  wherein said thrust forces from said at least three thrust members are transmitted by said panel through said first plate of a thermally insulating refractory material only to said second plate of a refractory material. 
     
     
       18. Device according to claim  17  wherein said belts are made of steel and said first belt is cooled by water. 
     
     
       19. Device according to claim  17  wherein said first plate of insulating refractory material has a thickness and said first belt has a width that is less than said thickness of said first plate of insulating refractory material. 
     
     
       20. A device for continuously casting a thin metal product between two rolls comprising two cooled counter- rotating rolls defining a generally triangular shaped cross - sectional casting space therebetween, a pair of side dams disposed adjacent a pair of ends of said counter - rotating rolls and said side dams each being of one piece construction, a pair of means for supporting and applying by pressure each of said side dams against an end of each of said rolls, wherein  ( a )  each of said side dams comprises a first plate of refractory material that contacts said pair of ends of said counter - rotating rolls during casting and which is surrounded by a first metallic belt that is operatively connected to said first plate, and  ( b )  each said supporting and pressure applying means comprises at least three thrust members that urge one of said side dams toward one of said pairs of ends of counter - rotating rolls, said at least three thrust members distributed over a zone of shape generally corresponding to that of said generally triangularly shaped cross - sectional casting space defined between said counter - rotating rolls with said thrust members applying a thrust force against a lower part of said side dam that is greater than a thrust force applied against an upper part of said side dam, said at least three thrust members exerting thrust forces on said side dam independently of one another, and each of said side dams further comprises  ( a )  a second plate of a thermally insulating refractory material disposed interjacent said at least three thrust members and said first plate of refractory material, and  ( b )  a second metallic belt that is operatively connected to said second plate, said second metallic belt permitting relative movement between said second plate and said second metallic belt in a direction toward or away from said one of said pairs of ends of said counter - rotating rolls.   
     
     
       21. A device according to claim  20  wherein each of said supporting and pressure applying means further comprises a support assembly that urges said side dam against said ends of said rolls. 
     
     
       22. A device according to claim  20  wherein each of said supporting and pressure applying means comprises a panel that carries said side dam. 
     
     
       23. A device according to claim  22  wherein for each of said supporting and pressure applying means, said side dam has a hook- shaped shaft that rests in a cradle in said panel attaching said side dam to said panel.   
     
     
       24. A device according to claim  22  wherein said supporting and pressure applying means further comprises a support carriage operatively connected to said panel. 
     
     
       25. A device according to claim  24  further comprising a thrust jack operatively connected to said support carriage for displacing said support carriage toward or away from said ends of said rolls thereby also displacing said side dam toward or away from said ends of said rolls. 
     
     
       26. A device according to claim  22  wherein said second plate of refractory material is disposed between said panel and said first plate of refractory material. 
     
     
       27. A device according to claim  26  wherein said second belt surrounds said second plate of refractory material and contains a coolant. 
     
     
       28. A device for continuously casting a thin metal product between two rolls comprising two cooled counter- rotating rolls, two side dams, a first support assembly that urges one of said side dams against one end of each of said rolls, a second support assembly that urges the other one of said side dams against another end of each of said rolls, wherein each of said side dams comprises a plate of refractory material that is surrounded about its entire periphery by a metallic belt connected to a cooled metal belt.   
     
     
       29. A device according to claim  28  wherein each of said support assemblies further comprises a movable support carriage that is constructed and arranged to urge one of said side dams against one of said ends of each of said rolls. 
     
     
       30. A device according to claim  29  further comprising a thrust jack operatively connected to said support carriage for displacing said support carriage toward or away from said ends of said rolls thereby also displacing said side dam toward or away from said ends of said rolls. 
     
     
       31. A device according to claim  28  wherein said metallic belt is operatively connected both to said plate and to a corresponding one of said support assemblies. 
     
     
       32. A device according to claim  28 , wherein the metallic belt surrounds only the periphery of the plate of refractory material. 
     
     
       33. A device according to claim  28 , wherein the metallic belt surrounds substantially only the periphery of the plate of refractory material. 
     
     
       34. A device for the continuous casting of metal between a pair of counter rotating rolls that define a generally triangular cross- sectional casting space therebetween comprising:    
       
         a pair of side dams spaced apart by the counter rotating rolls;  
       
       
         means for urging each of said side dams and means for supporting against ends of the counter rotating rolls, said means including:  
       
       ( a )  a thrust plate that can be moved in an axial direction relative to the counter rotating rolls and which is arranged generally perpendicular to said axial direction;    
       ( b )  a panel that supports one of said side dams and which is carried by said thrust plate and is arranged facing the latter;    
       ( c )  at least three thrust members interposed between said thrust plate and said panel, said thrust members being distributed over a zone of shape corresponding to that of the generally triangular casting space cross section between the counter rotating rolls, and being capable of exerting on said side dam thrust forces independently of one another;    
       ( d )  a support carriage for carrying said thrust plate and which can be moved in said axial direction; and    
       ( e )  wherein said side dam comprises  (   1   )  a plate of a thermally insulating refractory material surrounded by a first belt with said first belt carried by said plate for permitting displacement of said plate in a direction generally parallel to an axis of one of said rolls; and  (   2   )  a second plate of a refractory material surrounded by a second belt that is attached to said first belt and fixed to said second refractory plate for axial movement in unison with said second refractory plate and wherein thrust forces transmitted by said panel to said insulating refractory plate are transmitted by said insulating refractory plate to said second refractory plate.   
     
     
       35. A device for continuously casting a thin metal product between two rolls comprising two cooled counter- rotating rolls, a pair of side dams, a pair of means for supporting and applying by pressure each of said side dams against an end of each of said rolls, wherein each of said side dams comprises a plate of refractory materials surrounded by a metallic belt that is operatively connected to said plate, and wherein each of said supporting and pressure applying means comprises a panel that carries said side dam, a second plate of refractory materials that is disposed between said panel and said side dam, and a cooled belt surrounding said second plate of refractory material.   
     
     
       36. The device according to claim  35  wherein said second plate of refractory material is movable relative to said cooled belt in a direction toward or away from said end of one of said rolls. 
     
     
       37. A device for continuously casting a thin metal product between two counter- rotating rolls, comprising:    
       
         a plate of a thermally insulating refractory material that has a periphery that is surrounded by a first belt that permits movement of said thermally insulating refractory plate relative to said first belt in a direction generally parallel to an axis of rotation of one of said rolls;  
       
       
         a support assembly that urges a side dam against one end of one of both of said rolls with said side dam disposed between said plate of a thermally insulating refractory material and said one end of both of said rolls; and  
       
       
         a second belt surrounding the periphery of said side dam, said second belt being operably connected to said first belt and said side dam such that said second belt axially moves substantially in unison with said side dam. 
       
     
     
       38. A device for continuously casting a thin metal product between two counter- rotating rolls, comprising:    
       ( a )  a side dam that comprises  1   )  a first plate of a refractory material that bears against ends of said counter - rotating rolls during casting and having a first belt disposed around said first plate, and  2   )  a second plate of a refractory material disposed adjacent said first plate and having a second belt disposed around said second plate of a refractory material,    
       ( b )  at least three thrust members in operable cooperation with said side dam that urge said side dam toward said ends of said counter - rotating rolls, and    
       ( c )  wherein said second belt is carried by said second plate and permits relative movement between said belt and said second plate in a direction generally parallel to an axis of rotation of one of said counter - rotating rolls.   
     
     
       39. A device according to claim  38  wherein said second plate is an insulating plate that has a thickness greater than a width of said second belt and said second belt is hollow and contains a coolant during casting. 
     
     
       40. A device according to claim  39  wherein said first belt is attached to  1 )  said first plate and  2   )  said second belt.   
     
     
       41. A device according to claim  38  further comprising a panel that carries  1 )  said first and second plate and  2   )  said first and second belts, and wherein said second plate is disposed between said panel and said first plate.   
     
     
       42. A device according to claim  41  wherein said panel further comprises a cradle and said second belt further comprises a finger received in said cradle such that  1 )  said second belt is suspended from said panel, and  2   )  said second belt is movable in a direction generally parallel to an axis of rotation of one of said counter - rotating rolls.   
     
     
       43. A device according to claim  41  further comprising a coolant in said second belt. 
     
     
       44. A device according to claim  43  wherein said panel is internally cooled. 
     
     
       45. A device according to claim  41  wherein  1 )  said counter - rotating rolls define a generally triangularly - shaped cross - sectional casting space therebetween,  2   )  said at least three thrust members are distributed over a zone of shape that corresponds to said generally triangularly - shaped cross - sectional casting space, and  3   )  said at least three thrust members urge said panel, said first plate and said second plate toward said ends of said counter - rotating rolls during casting.   
     
     
       46. A device according to claim  45  comprising a plurality of thrust members that urge a lower part of said first refractory plate against said ends of said counter-rotating rolls by applying a first force, a plurality of thrust members that urge an upper part of said first refractory plate against said ends of said counter- rotating rolls by applying a second thrust force, and wherein said first force is greater than said second force.   
     
     
       47. A device according to claim  38  wherein  1 )  said counter - rotating rolls define a generally triangularly - shaped cross - sectional casting space therebetween,  2   )  said at least three thrust members are distributed over a zone of shape that corresponds to said generally triangularly - shaped cross - sectional casting space, and  3   )  said at least three thrust members urge said first plate against said ends of said counter - rotating rolls during casting.   
     
     
       48. A device according to claim  38  comprising a plurality of thrust members that urge a lower part of said first refractory plate against said ends of said counter- rotating rolls by applying a first force, a plurality of thrust members that urge an upper part of said first refractory plate against said ends of said counter - rotating rolls by applying a second thrust force, and wherein said first force is greater than said second force.