Abstract: The invention relates to a method for producing a silica glass tube which is characterized by depositing SiO2 particles on an elongate support that rotates about its longitudinal axis, thereby producing a porous with a cylindrical inner bore. Said blank is vertically aligned, suspended in a furnace using a suspension that engages with a constriction in the upper zone of the inner bore of the blank, and vitrified. The aim of the invention is to provided a method with which also heavy blanks can be secured safely and substantially without any danger of contaminations of the inner bore without using complicated securing devices. To this end, the constriction (6b) is generated by shaping the inner bore (7) when the SiO2 particles are deposited. For vitrification a suspension (8; 9; 10) is used that supports itself on the constriction (6b) and that otherwise projects into the cylindrical inner bore (7) without having any contact therewith.

Abstract: The invention relates to a method for producing a silica glass tube which is characterized by depositing SiO2 particles on an elongate support that rotates about its longitudinal axis, thereby producing a porous with a cylindrical inner bore. Said blank is vertically aligned, suspended in a furnace using a suspension that engages with a constriction in the upper zone of the inner bore of the blank, and vitrified. The aim of the invention is to provided a method with which also heavy blanks can be secured safely and substantially without any danger of contaminations of the inner bore without using complicated securing devices. To this end, the constriction (6b) is generated by shaping the inner bore (7) when the SiO2 particles are deposited. For vitrification a suspension (8; 9; 10) is used that supports itself on the constriction (6b) and that otherwise projects into the cylindrical inner bore (7) without having any contact therewith.

Abstract: The invention relates to a procedure for manufacture of a quartz glass body by deposition of SiO2 particles on the outer surface of a cylindrical mandrel rotating around its longitudinal axis under formation of an essentially cylindrical porous blank with an inside bore hole, and by removing the mandrel and sintering of the blank, characterized in that the mandrel in the area of one of the ends of the successively forming blank is surrounded by a shaping element rotating at the same rotation velocity as the mandrel, such shaping element having a core area facing the blank which is at least partially removably embedded into the front face of the successively forming blank and which is removed before sintering after having widened the inside bore hole of the blank with a shape complementary to that of the core area.