Patent ID: 8789391

Claim:
A method for producing a crucible of quartz glass, said method comprising: a step of vitrifying SiO 2 inner layer granules in a melting mold that rotates about an axis of rotation and comprises an inner wall, said melting mold having an upper side opening covered by a heat shield, said vitrifying being under the action of a plasma zone in atmosphere containing a light gas so as to form a transparent inner layer on a crucible base mold of quartz glass, at least part of the atmosphere containing the light gas being supplied to the melting mold through a gas inlet of the heat shield, wherein, in a layer-forming step preceding the vitrifying step, a granule layer of the SiO 2 inner layer granules is formed on the inner wall, and wherein the plasma zone and the heat shield together with the gas inlet are supported so as to be movable at least in a direction perpendicular to the rotation axis and are moved laterally in the direction of the granule layer during the vitrifying step so as to vitrify the granule layer; and wherein the upper side opening of the melting mold remains covered when the heat shield is moved laterally.