Continuous vacuum refining method of molten metal and apparatus thereof

A continuous vacuum refiner of molten metals comprising:

• a molten liquid receiver for temporarily retaining a molten liquid introduced into a vacuum chamber comprising a preheating means from the outside of the vacuum chamber through a molten liquid fall-down port;
• a molten liquid stirring part having a means for allowing the molten liquid to be temporarily retained and for stirring the molten liquid, and disposed so that the molten liquid communicates between the molten liquid receiver and the molten liquid stirring part;
• and
• a molten liquid tapping part disposed so that the molten liquid communicates between the molten liquid stirring part and the molten liquid tapping part, wherein a weir is provided for allowing the molten liquid in the molten liquid stirring part to overflow into the molten liquid tapping part, and a plurality of molten metal recovery pipes that transfers the overflowed molten liquid from the molten liquid tapping part into respective temporarily retaining vessels of the molten liquid in plural molten liquid recovery chambers placed at the outside of the vacuum chamber, are provided with their lower ends open in the molten liquid in the vessels,
• wherein each molten liquid recovery pipe has a capability of switching the refined molten liquid recovery chambers for discharging the molten liquid by providing stoppers for ON-OFF control of the flow speed of the molten liquid, and
• wherein an evacuation apparatus is connected to the vacuum chamber and refined molten liquid recovery chamber.