Apparatus for producing ingots of nonferrous metals by continuous casting

Abstract

An apparatus for producing ingots of nonferrous metals, comprising a continuous casting machine provided with a moving casting shell composed of a plurality of segments arranged in succession, each segment having a portion, with bottom and side walls, of the casting shell formed therein and being open on the sides directed toward the contiguous segments. The segments are movable along a closed path that has at least one substantially straight portion at the casting region. The segments, along the at least one portion of path, are substantially aligned and form a casting shell that is continuous and substantially straight and is closed, along at least one portion of path downstream of the casting region, by closure means at its side that is arranged opposite with respect to the bottom.

What is claimed is:  
     
         1 . An apparatus for producing, by continuous casting, ingots of nonferrous metals, comprising a continuous casting machine provided with a moving casting shell, wherein said shell is composed of a plurality of segments arranged in succession, each segment having a portion, with bottom and side walls, of said casting shell formed therein and being open on sides directed toward contiguous segments; said segments being movable along a closed path that has at least one substantially straight portion at the casting region; said segments, along said at least one portion of path, being substantially aligned and forming a casting shell, with a bottom and side walls, that is continuous, substantially straight and closed, along at least one portion of path downstream of the casting region, by closure means at its side that is arranged opposite with respect to the bottom; downstream of said substantially straight portion said segment path having a change in direction is for a gradual exit from said casting shell of a metal bar produced by solidification of the metal in the casting shell.  
     
     
         2 . The apparatus according to  claim 1 , wherein along said substantially straight portion the side of said casting shell that lies opposite the bottom is directed upward.  
     
     
         3 . The apparatus according to  claim 1 , wherein said substantially straight portion of the path of the segments, proximate to said casting region, is inclined downward in a direction in which the segments advance along said path.  
     
     
         4 . The apparatus according to  claim 3 , wherein said segments are connected to links of a chain that is closed in a loop and winds around at least two sprockets, which have mutually parallel horizontal axes; said substantially straight portion of the path of the segments being formed by the upper portion of said chain; at least one of said sprockets being actuatable with a rotary motion about its own axis in order to produce advancement of said segments along said path.  
     
     
         5 . The apparatus according to  claim 1 , wherein said closure means comprise a belt element that can move along a path that faces, with one of portions thereof, said substantially straight portion of the path of said segments; engagement means being provided which are suitable to press said belt element against said segments at said substantially straight portion of the path of the segments.  
     
     
         6 . The apparatus according to  claim 5 , wherein said belt element is closed in a loop and winds around at least two pulleys with horizontal axes that are parallel to the axes of said sprockets.  
     
     
         7 . The apparatus according to  claim 6 , wherein at least one of said two pulleys can be actuated with a rotary motion about its own axis in order to produce advancement of said belt so as to match advancement of said segments along the common portion of the path.  
     
     
         8 . The apparatus according to  claim 5 , further comprising means for cooling the metal poured into said segments along said substantially straight portion of the path of the segments.  
     
     
         9 . The apparatus according to  claim 8 , wherein said cooling means comprise a plurality of nozzles for dispensing a cooling fluid, which are suitable to strike said segments with said fluid.  
     
     
         10 . The apparatus according to  claim 8 , wherein said cooling means comprise a plurality of nozzles for dispensing a cooling fluid which are suitable to strike, with said fluid, a portion of said belt element that is pressed against said segments.  
     
     
         11 . The apparatus according to  claim 4 , wherein means for resting and guiding the chain that supports said segments are provided at said substantially straight portion of the path of the segments.  
     
     
         12 . The apparatus according to  claim 4 , wherein the links of said chain are mutually articulated by way of pivots whose axes are parallel to the axes of said sprockets; two wheels being mounted on each one of said pivots, proximate to their axial ends, and being suitable to rest, along said substantially straight portion of the path of the segments, on resting and guiding profiles.  
     
     
         13 . The apparatus according to  claim 6 , wherein said pulleys that support said belt element are mounted on a structure that can move toward and away from said substantially straight portion of the path of the segments.  
     
     
         14 . The apparatus according to  claim 1 , wherein the portion of said casting shell formed in each one of said segments has, in a transverse cross-section with respect to the direction of the advancement of said segments along the corresponding path, a trapezoidal shape that is open at the longer parallel side.  
     
     
         15 . The apparatus according to  claim 1 , further comprising, downstream of said continuous casting machine along the direction of the advancement of said segments along said substantially straight portion of their path, a first station for cooling the metal bar that exits from said continuous casting machine.  
     
     
         16 . The apparatus according to  claim 15 , further comprising, downstream of said first cooling station along the direction of advancement of the metal bar, a station for cropping said bar into segments.  
     
     
         17 . The apparatus according to  claim 16 , further comprising, downstream of said cropping station along the advancement direction of the metal bar, a second station for cooling the metal bar.  
     
     
         18 . A nonferrous metal ingot obtained by cropping a continuous bar, having a rectilinear structure free of plastic deformation after solidification, which occurs in a continuous shell formed by a sequence of concatenated segments of ingot mold and closed by a continuous belt element, metallographic discontinuities being detectable in said ingot in the sections that correspond to the contact surfaces of the various segments that compose said shell.  
     
     
         19 . A method for producing, by continuous casting, ingots of nonferrous metals, comprising the steps of: 
 continuously casting the molten metal within a continuous and substantially rectilinear moving casting shell that is composed of a sequence of concatenated segments of an ingot mold;    cooling said casting shell for the at least partial solidification of the cast metal;    extracting continuously the bar produced by the solidification of the metal from said casting shell without producing plastic deformations of said bar;    cropping said bar into segments.