| 摘要 |
PURPOSE:To prevent occurrence of stainlike unevenness of film and the deterioration of the flux decline factor, by thermally softening the both end sections of a glass tube and applying contracting work on it, while uniformly heating the central section of the glass by means of gas burner, or the like. CONSTITUTION:A glass tube 5 made of a soda lime glass for 40W linear tube is held on a rotary roll 2, then the central portion of said glass tube 5 except 10cm of both ends is placed in a heating furnace 6. While rotating said glass tube 5 in said furnace 6, the both end sections of said glass tube 5 which are left outside of said furnace 6 are heated by a gas burner 3 and softened to perform the contracting work by means of a block 4. |
