METHOD OF MAKING A SILICA CRUCIBLE IN A CONTROLLED ATMOSPHERE, SUPPLYING HELIUM OR HYDROGEN WHILE SILICA GRAINS BEING HEATED AND FUSED

摘要

PURPOSE: A method of making a silica crucible in a controlled atmosphere is provided to increase the apparent density of a gas supplied to the hollow of a mold by improving the bubble property in a crucible.;CONSTITUTION: In a method of making a silica crucible in a controlled atmosphere, a mold(12) comprises a plurality of air channels communicating with the mold surface(22). The air channel comprises a porous graphite plug(24). A rotary union(34) is connected to a three-way valve(38) through a conduit(36). A vacuum pump(40) offers programmable electricity. A power supply unit(58) supplies voltage while crossing the set of electrodes(60,62).;COPYRIGHT KIPO 2011