| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a glass preform for an optical fiber wherein the occurrence of soot cracks, i.e., the cracks occurring in a glass particulate deposit, due to the falling down of glass particulates during synthesis and the occurrence of air bubbles in the glass body are prevented by decreasing the amount of glass particulates adhering to the inner surface of a reactor. SOLUTION: The occurrence of soot cracks caused by the peeling off and falling down of the glass particulate deposit 14 in the course of its synthesis in the reactor 10 due to the falling down of glass particulates 18a adhering to the inner surface of the reactor 10 is prevented by installing a partition plate 20 for preventing a downflow stream 17 supplied into the reactor 10 from the direct collision against the glass particulate deposit. By setting the flow rate of the downflow stream on the inner wall at 1 m/sec or higher, the amount of the glass particulates adhering to the inner wall surface of the reactor 10 is decreased. By increasing the flow rate of the downflow stream 17 at the opposite side to a burner 15, the adhesion of glass particulates 18a to the inner wall surface of the reactor 10 is made difficult. By preventing the temperature decrease of a fitting section of a reactor upper part 12 for fitting it to the reactor body 11 by using a heat insulating material 19, the amount of the adhering glass particulates 18a is decreased. COPYRIGHT: (C)2004,JPO |
