Abstract: A known method for producing a cylinder of quartz glass comprises a soot depositing process, in which SiO2 particles are deposited on an elongate carrier rotating about an axis of rotation with formation of a porous, hollow-cylindrical soot body, and a sintering process in which the soot body comprising an inner bore with inner wall, a longitudinal axis, an upper end and a lower end is held suspended in vertical orientation in a furnace, a holding element being provided for holding purposes, which projects from the upper end into the inner bore of the soot body and acts on a bearing provided in the inner bore.

Abstract: Methods of plastically forming an axially extended zone of the interior surface of a hollow glass tube heated to its forming temperature employ a generally cylindrical embossing mandrel connected to a driving shaft. The hollow glass tube and the embossing mandrel are brought together at a predetermined start position for the embossing mandrel inside the glass tube and are brought into contact in an area in which the zone is to be formed on the interior surface of the glass tube. A relative rolling off planetary motion between the embossing mandrel and the glass tube is provided while plastically forming the zone of the glass tube and creating depressions therein.

Abstract: Apparatus for forming a groove in a glass tube without contacting the glass tube in the groove region. The apparatus includes a pair of chucks for holding opposite ends of the glass tube. The chucks are coupled to a motor for rotating the glass tube about its longitudinal axis. The apparatus further includes one or more torches for noncontact heating of the groove region of the glass tube sufficiently to soften the glass tube in the groove region. The chucks which hold the glass tube are axially movable for stretching and then compressing the glass tube along its longitudinal axis, when the glass tube has been softened in the groove area. The chucks are rotated during heating, stretching and compressing of the glass tube.

Abstract: A machine for fabricating articles such as glass vials from tubular stock includes a plurality of rotating chucking stations which revolve about the central vertical axis of the machine and a plurality of tooling stations which form the vial finish. The plurality of tooling stations are disposed in euqal numbers related to the number of chucking stations on two conveyor assemblies disposed adjacent the periphery of the circle defined by the revolving chucking stations. The tooling stations each include rollers which form the outside of the vial finish and a segmented mandrel which forms the inside of the vial finish including, if desired, a blowback cavity.