| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high-quality glass tube by inhibiting deformation of the glass tube immediately after piercing. SOLUTION: In a process for manufacturing the glass tube, a glass rod 3 is heated and softened by a heating element 41 placed around it, and a piercing tool 30 is press-fitted into the softened part of the glass rod 3 to gradually mold the glass rod 3 into the glass tube 6. Here, pressures applied to inner and outer sides of the glass tube 6, preferably, internal and external pressures of the glass tube 6, are controlled. Preferably, a top 31 is heated to a temperature equal to or higher than the softening point of the glass rod. COPYRIGHT: (C)2004,JPO
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