Tundish impact pad

Abstract

A tundish impact pad formed from refractory material is disclosed, the impact pad comprising a base having an impact surface which in use faces upwardly to receive molten metal, e.g. steel, poured onto the impact pad, and a sidewall extending upwardly from at least part of the periphery of the impact surface. At least part of the interior, and a surface, of the sidewall are porous and the impact pad includes means for supplying a gas, e.g. argon, to the porous interior of the sidewall, to enable the gas to be supplied to the molten metal from the porous surface of the sidewall. The tundish impact pad may be used during the continuous casting of steel.

1 . A tundish impact pad formed from refractory material, the impact pad comprising a base having an impact surface which in use faces upwardly to receive molten metal poured onto the impact pad, and a sidewall extending upwardly from at least part of the periphery of the impact surface, characterised in that at least part of the interior, and a surface, of the sidewall are porous and the impact pad includes means for supplying a gas to the porous interior of the sidewall, to enable the gas to be supplied to the molten metal from the porous surface of the sidewall.  
     
     
         2 . A kit of parts for assembly to form a tundish impact pad, comprising: 
 (a) a base part formed from refractory material and having an impact surface for receiving molten metal poured onto the impact pad in use; and    (b) a peripheral sidewall part formed from refractory material, for attachment directly or indirectly to the base part to form at least part of a sidewall around at least part of the periphery of the impact surface; characterised in that at least part of the interior, and a surface, of the sidewall part are porous, and the base part and/or the sidewall part include(s) means for supplying a gas to the porous interior of the sidewall part, to enable the gas to be supplied to the molten metal from the porous surface of the sidewall part.    
     
     
         3 . A tundish for containing molten metal, the tundish comprising a floor and sidewalls formed from refractory material, and further comprising an outlet for the molten metal, characterised in that the tundish contains an impact pad according to  claim 1  or an impact pad assembled from a kit according to  claim 2 , placed on the floor of the tundish.  
     
     
         4 . A method of removing inclusions from molten metal in a tundish, by means of a tundish impact pad according to  claim 1  or an impact pad assembled from a kit according to  claim 2 , the method comprising supplying a gas to the molten metal from the porous sidewall of the impact pad.  
     
     
         5 . An impact pad, kit, tundish or method according to any preceding claim, in which the sidewall is porous in only an upper portion thereof.  
     
     
         6 . An impact pad, kit, tundish or method according to any preceding claim, in which at least part of an upper surface of the sidewall is porous.  
     
     
         7 . An impact pad, kit, tundish or method according to any preceding claim, in which the sidewall includes an inwardly projecting ledge.  
     
     
         8 . An impact pad, kit, tundish or method according to  claim 7 , in which at least part of the porosity of the sidewall comprises at least part of the ledge.  
     
     
         9 . An impact pad, kit, tundish or method according to any preceding claim, in which the means for supplying a gas to the interior of the sidewall comprises one or more conduits.  
     
     
         10 . An impact pad, kit, tundish or method according to  claim 9 , in which the or each conduit is perforated along at least part of its length.  
     
     
         11 . An impact pad, kit, tundish or method according to any preceding claim, in which the gas is an inert gas, preferably argon.  
     
     
         12 . An impact pad, kit, tundish or method according to any preceding claim except  claim 1  or  claim 2 , in which the tundish includes one or more gas supply conduits for supplying the gas to the impact pad.  
     
     
         13 . An impact pad, kit, tundish or method according to  claim 12  when dependent upon  claim 9  or  claim 10 , in which at least one conduit in the tundish is connected to a respective conduit in the impact pad.