PRODUCTION OF QUARTZ GLASS PERFORM

摘要

PURPOSE:To provide the production of a quartz glass perform of high quality in good yield. CONSTITUTION:When a porous glass body 33 is formed, a bar body 31 having the coefficient of expansion equal to or more than that of metal is put in a forming space 20 and a forming material 32 is packed around it and compressed. After that, a quartz glass bar 34 is inserted into a residual hole which the bar body 31 is pulled out from the porous glass body 33 to make the porous glass body 33 purified at high temp. and to convert it transparent glass. Since the generating rate of cracks in the porous glass body 31 is kept relatively low and the bubble generation from the interface between a transparent glass layer 35 after transparent glass conversion and the glass bar 34 is prevented depending on the bar body 31 causing no breakage, a quartz glass perform of high quality is obtained in good yield.