摘要 |
A process for minimizing foam formation on the top surface of molten metal during free falling of molten metal, such as molten zinc, into moulds, launders or other containers is disclosed. The process comprises the steps of forming a body of substantially dross-free molten metal, introducing a non-oxidizing gas into the container to form an essentially non-oxidizing atmosphere with respect to the molten metal, free falling the molten metal from the body of molten metal into the container, and maintaining the molten metal during the free falling thereof under an essentially non-oxidizing atmosphere, so as to prevent entrainment of sufficient oxygen into the molten metal by the falling stream to form excessive quantities of bubbles having a tenacious oxidized film and which do not collapse when they float to the surface of the molten metal but rather produce undesirable foam on the surface of molten metal.
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