METHOD FOR CONTROLLING HEAT TREATMENT IN HIGH-PURITY SILICA GLASS MANUFACTURING PROCESS

PROBLEM TO BE SOLVED: To provide a method for controlling heat treatment in a high-purity silica glass manufacturing process by which silica glass having a uniform characteristic is repeatedly manufactured even if the size of the exhaust line of low- temperature heat-treating equipment is changed. SOLUTION: This invention is referred to the sol-gel silica glass manufacturing process utilizing the low-temperature heat-treating equipment provided with the suction line and exhaust line for charging or discharging a process gas. The process includes a first stage for confirming whether the size of the exhaust line is changed or not, a second stage for controlling the supply flow rate of the process gas as the size of the exhaust line is changed, a third stage for measuring the speed of the exhaust gas discharged through the exhaust line and a fourth stage for comparing the exhaust gas speed measured in the third stage with the reference exhaust gas speed as the exhaust gas speed before the size of the exhaust line is changed and feeding the result back to the second stage when both speeds are different from each other to equalize both of the speeds.