VERTICAL CRUCIBLE DRAWING METHOD FOR PRODUCING A CYLINDRICAL QUARTZ GLASS BODY AND DEVICE FOR CARRYING OUT THIS METHOD

摘要

A known vertical crucible drawing method for producing a cylindrical quartz glass body involves the continuous drawing of a quartz glass melt, which is softened in a melting crucible, via a drawing nozzle (10), which is placed in a bottom opening of the melting crucible and which has a drawing nozzle opening, said drawing being effected vertically downward whereby forming a quartz glass strand with a predetermined cross-sectional profile. The aim of the invention is to improve this known crucible drawing method whereby enabling a broadening of the geometry spectrum of the quartz glass strand to be drawn without a significant technical or constructive effort. To this end, the invention provides that the drawing nozzle is connected via its side facing away from the melting crucible to an exchangeable attachment nozzle (1), which has an attachment nozzle opening (9) whose opening cross-section differs from that of the drawing nozzle opening. The invention also provides that the profile of the quartz glass strand is established by cooling the quartz glass melt in the drawing nozzle and in the attachment nozzle according to the opening cross-section of the attachment nozzle opening.