| 摘要 |
PURPOSE:To effect uniform size and density by controlling the flow rate of exhaust gases to a preset rate with the use of a valve, which is mounted in an exit, so that porous glass may be grown under stable conditions. CONSTITUTION:Porous glass 22 is grown in a reactor 23. A valve 26 connected with an exit 24 is arranged such that the gas flow rate is metered by a gas flow meter 27 arranged in the same piping and is held at a preset rate. A pressure gauge 30 is attached to the reactor 23 to take out the pressure in the reactor as electric signals thereby to control the preset pressure. The discharge of water vapor, chroline or hydrogen chrolide generated as a result of the glass composing reaction is held at a preset level, and the gas flow in the reactor 23 is stabilized so that the O.D. and density of the rod can be uniformalized. |
