VACUUM REFINING OF GLASS OR THE LIKE WITH ENHANCED FOAMING

摘要

Foaming of molten glass or the liks as it enters a vacuum refining vessel is enhanced by altering the incoming stream so as to increase its surface area and/or retarding the passage of the stream through the vacuum headspace so as to increase its exposure to the vacuum. The stream of the molten glass entering the vacuum chamber is provided with a shape other than a single cylindrical shape along at least a portion of its passage into the chamber.