herres

Claim 1

IN REMOVING IMPURITIES FROM UNREFINED TITANIUM METAL WHICH IS SUBJECT TO CARBON AND AIR CONTAMINATION, AND IN MELTING AND DIRECTLY BUILDING UP A PURE QUALITY METAL INGOT THEREFROM IN AN INCLOSED ARC-MELTING FURNACE HAVING A LONGITUDINALLY-EXTENDING HEARTH TERMINATING AT ITS FRONT END IN SUCH INGOT MOLD AND HAVING A FEED CHUTE OPEN TO THE OPPOSITE END OF THE HEARTH ABOVE A MELTING LEVEL THEREIN, THE METHOD WHICH COMPRISES, INTRODUCTING UNREFINED METAL IN SOLID FORM THROUGH AND ALONG THE FEED CHUTE INTO THE FURNACE AT THE OPPOSITE END OT THE HEARTH, MAINTAINING AN ATMOSPHERE WITHIN THE FURNACE THAT IS NON-CONTAMINATING OF THE METAL, PRELIMINARILY HEATING THE THUS-INTRODUCED METAL AT SUCH OPPOSITE END OF THE HEARTH TO A TEMPERATUE WELL ABOVE THE VOLATILIZING POINT OF IMPURITIES THEREIN AND TO ABOUT THE MELTING POINT OF THE METAL AND REFINING THE METAL THEREAT BY RELEASING THE VOLATILIZED IMPURITIES THEREIN; MELTING THE THUS-PRUIFIED METLA AND, AFTER THE METAL HAS BEEN MELTED INTO A MOLTEN CONDITION, INCREASING AND MAINTAINING THE TEMPERATURE OF THE MOLTEN METAL FROM SUCH OPPOSITE END OF THE HEARTH