System for optically analyzing a molten metal bath

Abstract

A system for optically analyzing a molten metal bath wherein a high velocity argon gas stream is passed from a lance to the bath and is maintained coherent by a flame envelope to provide a clear sight pathway through the argon gas stream for sighting the molten metal bath longitudinally through the argon gas stream from a remote or spaced sighting point.

1 . A method for optically analyzing a molten metal bath comprising: 
 (A) forming a coherent argon gas stream by passing an argon gas stream out from a lance and surrounding the argon gas stream with a flame envelope;    (B) passing the coherent argon gas stream to a molten metal bath;    (C) sighting longitudinally through the coherent argon gas stream to view the molten metal bath and obtain optical data therefrom; and    (D) passing the optical data to an analyzer.    
     
     
         2 . The method of  claim 1  wherein the sighting through the coherent argon gas stream comprises using a light source transmitting light through the coherent, argon gas stream.  
     
     
         3 . The method of  claim 2  wherein the light source is a laser.  
     
     
         4 . The method of  claim 1  wherein the flame envelope extends from the lance to the molten metal bath.  
     
     
         5 . The method of  claim 1  wherein the coherent argon gas stream has a supersonic velocity when it contacts the molten metal bath.  
     
     
         6 . The method of  claim 1  wherein the optical data enables the determination of the composition of the molten metal of the molten metal bath.  
     
     
         7 . The method of  claim 1 , wherein the optical data enables the determination of the temperature of the molten metal of the molten metal bath.  
     
     
         8 . The method of  claim 1  wherein the molten metal bath comprises unmelted scrap and the optical data enables the determination of melted versus unmelted scrap in the molten metal bath.  
     
     
         9 . The method of  claim 1  wherein the molten metal bath comprises molten metal and a slag layer above the molten metal, and wherein the coherent argon gas stream passes through the slag layer to the molten metal.  
     
     
         10 . Apparatus for optically analyzing a molten metal bath comprising: 
 (A) a molten metal furnace containing a molten metal bath;    (B) a lance having an ejection end for passing a coherent argon gas stream to the molten metal bath;    (C) a sight glass mounted on the lance on the end opposite the ejection end to provide a pressure seal to prevent leakage of argon gas from the lance while providing an optically transparent view port and aligned so as to view the molten metal bath longitudinally through the coherent argon gas stream to obtain optical data; and    (D) an analyzer and means for passing the optical data to the analyzer.    
     
     
         11 . The apparatus of  claim 10  further comprising a light source for generating light for passage through the coherent argon gas stream.  
     
     
         12 . The apparatus of  claim 11  wherein the light source is a laser.  
     
     
         13 . The apparatus of  claim 10  wherein the lance is positioned so as to provide the coherent argon gas stream to the molten metal bath in a direction perpendicular to the surface of the molten metal bath.  
     
     
         14 . The apparatus of  claim 10  wherein the means for passing optical data to the analyzer comprises a light guide assembly comprising optical fiber passing from the sight glass to the analyzer.  
     
     
         15 . The apparatus of  claim 10  wherein the means for passing optical data to the analyzer comprises a light guide assembly comprising a system of lenses and mirrors.  
     
     
         16 . The apparatus of  claim 10  wherein the analyzer comprises an optical spectrometer.  
     
     
         17 . The apparatus of  claim 10  wherein the analyzer comprises a pyrometer.