Method for Melting Magnesium and Melting Apparatus

Abstract

An object of the present invention is to provide a melting method for magnesium or a magnesium alloy which detects certainly and immediately combustion of a magnesium melt and emits alarm immediately based on the detection results, and extinguishes immediately the magnesium combustion, in order to achieve the object, the present invention provide a method for melting magnesium while supplying a cover gas containing carbon dioxide and a fireproof agent in a furnace for melting magnesium and obtaining a magnesium melt to cover the surface of the magnesium melt, wherein concentration of carbon monoxide in the furnace or gas discharged from the furnace is measured and magnesium combustion in the furnace is detected based on the concentration of carbon monoxide.

1 . A method for melting magnesium or a magnesium alloy while supplying a cover gas containing carbon dioxide and a fireproof agent in a furnace for melting magnesium or a magnesium alloy and obtaining a magnesium melt or a magnesium alloy melt to cover the surface of the magnesium melt, 
 wherein a concentration of carbon monoxide in the furnace or gas discharged from the furnace is measured and magnesium combustion in the furnace is detected based on the concentration of carbon monoxide.    
     
     
         2 . A method for melting magnesium according to  claim 1 , wherein the magnesium combustion is prevented by increasing a flow rate of the cover gas or concentration of the fireproof agent contained in the cover gas when magnesium combustion is confirmed.  
     
     
         3 . A method for melting magnesium according to  claim 1 , wherein the fireproof agent is 1,1,1,2,2,4,4,5,5,5,-nonafluoro-4-(trifluoromethyl)-3-pentanone.  
     
     
         4 . A melting apparatus for magnesium comprising: 
 a furnace for melting magnesium and obtaining a magnesium melt;    a cover gas supplying portion for supplying a cover gas containing carbon dioxide and a fireproof agent in the furnace;    a carbon monoxide concentration meter for measuring concentration of carbon monoxide in the furnace or gas discharged from the furnace; and    a control portion for controlling a supply rate of the fireproof agent in the furnace based on the concentration of carbon monoxide measured by the carbon monoxide concentration meter.    
     
     
         5 . A melting apparatus for magnesium comprising: 
 a furnace for melting magnesium and obtaining a magnesium melt;    a cover gas supplying portion for supplying a cover gas containing carbon dioxide and a fireproof agent in the furnace;    a carbon monoxide concentration meter for measuring a concentration of carbon monoxide in the furnace or gas discharged from the furnace; and    a control portion for controlling a supply rate of the cover gas in the furnace based on the concentration of carbon monoxide measured by the carbon monoxide concentration meter.    
     
     
         6 . A melting apparatus for magnesium according  claim 4 , wherein the control portion has signal generation function which emits a signal showing magnesium combustion when magnesium combustion is confirmed, and a display portion for showing magnesium combustion based on the signal.