Refractory plate

Abstract

The invention concerns a refractory plate, in particular for a system of liquid molten metal flow, comprising at least two zones when considering the main plane of the plate: a passage zone ( 1 ) with at least a passage hole ( 3 ) for said liquid metal and a composition resistant to stresses resulting from the flow of the liquid metal through the hole ( 3 ), and a manoeuvring zone ( 2 ) designed to stop the liquid metal flow, and a composition, different from that of the passage zone ( 1 ), selected to resist in particular thermal shocks when the flow stops, the zones taking up the entire thickness of the plate wherein the securing link between the passage zone ( 1 ) and the manoeuvring zone ( 2 ) results from joint pressing, in a common mould, the composition of the passage zone(s) and the composition of the manoeuvring zone ( 2 ), the compositions having previously been deposited into the mould respectively along the zones, followed by consolidating heat treatment. The invention also concerns a method for making said plate.

1 . Refractory plate, in particular for a system for regulating the flow of a liquid molten metal, comprising at least two zones considering the principal plane of the said plate: 
 at least one passage zone ( 1 )    which comprises at least one passage hole ( 3 ) for the said liquid metal,    with a composition chosen to withstand in particular stresses due to contact with the said liquid metal flowing through the hole ( 3 ),    a manoeuvring zone ( 2 ) intended to conduct the regulation,    which is intended to stop the flow of the liquid metal, and    with a composition different from the composition of the passage zone ( 1 ), chosen so as to withstand in particular thermal shocks due to the liquid metal in abutment on this manoeuvring zone ( 2 ) in the event of stoppage of the flow, and    a connection for fixing together the said zones, in order to form a single-piece assembly,    characterised in that the said zones each take up the entire thickness of the plate and the fixing connection between the passage ( 1 ) and manoeuvring ( 2 ) zones is the result of a co-pressing, in the same mould, of the composition constituting the passage zone or zones ( 1 ) and the different composition constituting the manoeuvring zone ( 2 ), the different compositions previously having been disposed in the mould respectively according to the zones, followed by a consolidation heat treatment.    
     
     
         2 . Refractory plate according to  claim 1 , characterised in that the passage zone or zones ( 1 ) and the manoeuvring zone ( 2 ) are directly connected to each other structurally.  
     
     
         3 . Refractory plate according to  claim 1 , characterised in that the casting hole or holes ( 3 ) in the passage zone or zones ( 1 ) are produced by boring the plate after the co-pressing of the compositions.  
     
     
         4 . Refractory plate according to  claim 1 , characterised in that the casting hole or holes in the passage zone or zones ( 1 ) are obtained directly by the use of a core during the co-pressing.  
     
     
         5 . Refractory plate according to  claim 1 , characterised in that the passage zone or zones ( 1 ) are enclosed within the manoeuvring zone ( 2 ).  
     
     
         6 . Refractory plate according to  claim 5 , characterised in that the enclosed passage zone ( 1 ) comprises several casting holes ( 3 ).  
     
     
         7 . Refractory plate according to  claim 1 , characterised in that the passage zone or zones ( 1 ) and the manoeuvring zone ( 2 ) are contiguous.  
     
     
         8 . Refractory plate according to  claim 1 , characterised in that the passage zone or zones ( 1 ) are provided, at each casting hole ( 3 ), with a nesting and centring system for a refractory piece contiguous with the casting system.  
     
     
         9 . Refractory plate according to  claim 1 , characterised in that the composition of the passage zone or zones ( 1 ) consists of 
 prime-grade refractory grains belonging to the family of alumina, mullite, zirconia and composites thereof,    divided carbon which may be of the graphite, anthracite, coke or carbon black type,    antioxidants, and    a thermosetting resin.    
     
     
         10 . Refractory plate according to  claim 1 , characterised in that the composition of the manoeuvring zone ( 2 ) consists of 
 refractory grains belonging to the silico-alumina system, such as bauxite, andalusite, kyanite and chamotte, and/or    in whole or in part, refractory grains resulting from a recycling process, bonded by a carbonaceous agent compatible with that of the passage zone ( 1 ).    
     
     
         11 . Refractory plate according to  claim 1 , characterised in that the composition of the passage zone ( 1 ) comprises prime-grade refractory grains of magnesia and/or spinel MgO Al2O3, divided carbon, antioxidants and a thermosetting resin, and in that the composition of the manoeuvring zone ( 2 ) comprises less noble refractory grains belonging to the same system as those of the other zone ( 1 ) and, in whole or in part, resulting from a recycling process, bonded by a carbonaceous bonding agent compatible with that of the passage zone ( 1 ).  
     
     
         12 . Method of manufacturing a refractory plate, in particular for a system for regulating the flow of a liquid molten metal, comprising at least two zones, considering the principal plane of the said plate: 
 at least one passage zone ( 1 ) for a first given composition, and    a manoeuvring zone ( 2 ) for a second given composition, forming the rest of the plate,    the method being characterised in that it comprises    the addition in a mould, firstly, of one or more volumes of the composition for the passage zone or zones ( 1 ) and, secondly, a volume of the other composition for the manoeuvring zone ( 2 ), complying with the required geometric limits for each corresponding zone, the composition chosen for each zone being identical therein over the entire thickness of the plate,    simultaneous pressing of the two compositions in the mould in order to give the required shape and compactness to the pressed plate, and    consolidation heat treatment of the pressed plate.    
     
     
         13 . Method according to  claim 12 , characterised in that it comprises 
 for the separate addition of the compositions, a partitioning of the distinct zones in the mould, and    before pressing, a removal of the partitioning.    
     
     
         14 . Method according to one or other of claims  12  and  13 , characterised in that, after the pressing of the plate, the casting hole or holes ( 3 ) are produced by boring.  
     
     
         15 . Method according to one or other of claims  12  and  13 , characterised in that it comprises, in order to make the casting hole or holes ( 3 ), the use of a moulding core.