Production of a thin discoid glass blanks comprises pressing glass gobs into a molding tool so that the molding edge of the molding tool does not impede the deformation of the gob in the radial direction

摘要

Production of a thin discoid glass blanks comprises pressing glass gobs into a molding tool having an upper tool (1) and a lower tool (3). The molding edge of the molding tool does not impede the deformation of the gob in the radial direction. The viscosity of the gob is adjusted to below 10 dPas during delivery to the molding tool. During pressing, the biconcave contour of the outer surface of the glass blank (4) is formed. The cooled blank is ground or polished using plane grinding tools whose diameter is greater than that of the glass blank, and at least one biconcave overmeasure of the blank edge is removed. An Independent claim is also included for a device for pressing glass gobs.