Treatment ladle

Abstract

A treatment ladle comprising a ladle shell containing a generally tubular refractory ladle liner, said ladle being pivotable between a horizontal position and a vertical position, said ladle liner having a first end and a second end with a continuous sidewall therebetween, an interior space being defined between said first and second ends and the continuous sidewall, said ladle liner additionally comprising a pocket for holding a treatment agent, said pocket being located adjacent the first end and in fluid communication with the interior space and located closer to the top than the bottom of the interior space when the ladle is in its horizontal position and closer to the bottom than the top of the interior space when the ladle is in its vertical position, and a spout for receiving and pouring molten metal located closer to the top than the bottom of the interior space when the ladle is in its horizontal and vertical positions, wherein in the horizontal position, a lower volume of the interior space defined below a plane midway between the top and bottom of the interior space and between the first end and a vertical plane intermediate the first and second ends is greater than an upper volume of the interior space defined above the midway plane and between the first end and said vertical plane. The treatment ladle is designed for the treatment of molten metal with vaporisable additives, in particular in the preparation of ductile iron. The invention also relates to a method of treating molten metal employing the ladle.

1 .- 15 . (canceled) 
     
     
         16 . A treatment ladle comprising a ladle shell containing a generally tubular refractory ladle liner, said ladle being pivotable between a horizontal position and a vertical position,
 said ladle liner having a first end and a second end with a continuous sidewall therebetween, an interior space being defined between said first and second ends and the continuous sidewall,   said ladle liner additionally comprising a pocket for holding a treatment agent, said pocket being located adjacent the first end and in fluid communication with the interior space and located closer to the top than the bottom of the interior space when the ladle is in its horizontal position and closer to the bottom than the top of the interior space when the ladle is in its vertical position, and a spout for receiving and pouring molten metal located closer to the top than the bottom of the interior space when the ladle is in its horizontal and vertical positions,   wherein in the horizontal position, a lower volume of the interior space defined below a plane midway between the top and bottom of the interior space and between the first end and a vertical plane intermediate the first and second ends is greater than an upper volume of the interior space defined above the midway plane and between the first end and said vertical plane.   
     
     
         17 . The ladle in accordance with  claim 16 , wherein the pocket extends from the first end of the ladle liner away from the interior space. 
     
     
         18 . The ladle in accordance with  claim 16 , wherein the ratio of the lower volume to the upper volume is at least 1.5:1. 
     
     
         19 . The ladle in accordance with  claim 16 , wherein the ratio of the height of the interior space when the ladle is in its vertical position to the height of the interior space when the ladle is in its horizontal position is at least 2:1 
     
     
         20 . The ladle in accordance with  claim 16 , wherein the ratio of the height of the interior space when the ladle is in its vertical position to the height of the interior space when the ladle is in its horizontal position is no more than 6:1. 
     
     
         21 . The ladle in accordance with  claim 16 , wherein the pocket extends from the first end of the ladle liner away from the interior space and the ratio of the height of the interior space when the ladle is in its vertical position to the length of the pocket is at least 2:1. 
     
     
         22 . The ladle in accordance with  claim 16 , wherein the continuous sidewall is defined by three or more wall portions such that the cross-section of the continuous sidewall is substantially polygonal. 
     
     
         23 . The ladle in accordance with  claim 22 , wherein the continuous sidewall is defined by three wall portions, such that the cross-section of the continuous sidewall is substantially triangular. 
     
     
         24 . The ladle in accordance with  claim 22 , wherein the corners of the polygon are rounded and/or the sides of the polygon are bowed outward. 
     
     
         25 . The ladle in accordance with  claim 16 , wherein the continuous sidewall is defined by three sidewall portions, such that the cross-section of the continuous sidewall is substantially triangular and the ratio of the height of the interior space when the ladle is in its vertical position to the length of at least one of the sidewall portions is at least 1.5:1. 
     
     
         26 . The ladle in accordance  claim 16 , wherein the continuous sidewall is of unitary construction. 
     
     
         27 . The ladle in accordance with  claim 16 , wherein the ladle shell and the ladle liner have substantially the same shape 
     
     
         28 . A method for the treatment of molten metal comprising
 loading the ladle of  claim 16  by placing a treatment agent in the pocket,   filling the ladle with molten metal whilst it is in its horizontal position to a level below the pocket, and   pivoting the ladle to its vertical position such that molten metal flows onto the treatment agent in the pocket.   
     
     
         29 . The method of  claim 28 , wherein the ladle is pivoted greater than 90° from the horizontal position, via the vertical position to a dispensing position in which the treated molten metal is dispensed through the spout. 
     
     
         30 . The method of  claim 28 , wherein the treatment agent is a nodulariser.