APPARATUS AND METHOD FOR MANUFACTURING QUARTZ GLASS TUBE OR ROD, AND QUARTZ GLASS TUBE AND ROD

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing apparatus and a manufacturing method by which a quartz glass tube or rod having small ellipticity is stably obtained and to provide the quartz glass tube and the quartz glass rod. SOLUTION: In the manufacturing apparatus for the quartz glass tube or rod which is provided with a heating furnace having a vertical tubular heating element for drawing a large sized cylindrical or columnar quartz glass preform into the quartz glass tube or rod of prescribed size, a plurality of inert gas blow-out ports are provided over the whole circumference of a large sized circular quartz glass preform charging port on the upper part of the heating furnace with a uniform interval in the circumferential direction so as to blow out an inert gas downward into the furnace inside part, and the difference between the flow rate of the inert gas from each inert gas blow-out port and a reference introducing flow rate which is an average value of the inert gas flow rate from the whole inert gas blow-out ports is controlled to≤±10% of the reference introducing flow rate. COPYRIGHT: (C)2006,JPO&NCIPI