A system for use in a glass drawing process includes: a tensioning element; a refractory tube having a tubular element and a surface element, the refractory tube being configured so molten glass runs onto a contact surface area of the refractory tube during a glass drawing process, the contact surface area of the refractory tube being allocated at least in part on the surface element, the surface element covering at least one surface of an end section of the tubular element, and the surface element projects at least in part over the end section of the tubular element, at least one portion of the part of the surface element projecting over the end section of the tubular element being connected at least in part to the tensioning element; and a carrier that carries the refractory tube and is connected with the refractory tube in a non-rotating manner.

A system for use in a glass drawing process includes: a tensioning element; a refractory tube having a tubular element and a surface element, the refractory tube being configured so molten glass runs onto a contact surface area of the refractory tube during a glass drawing process, the contact surface area of the refractory tube being allocated at least in part on the surface element, the surface element covering at least one surface of an end section of the tubular element, and the surface element projects at least in part over the end section of the tubular element, at least one portion of the part of the surface element projecting over the end section of the tubular element being connected at least in part to the tensioning element; and a carrier that carries the refractory tube and is connected with the refractory tube in a non-rotating manner.

A glass tube has a center axis, where for the glass tube a specific cross-sectional plane is defined which includes the center axis and which is parallel to the center axis. Within the specific cross-sectional plane, for each pair of outer diameters d1 and d2 of the glass tube at any two arbitrarily selected first axial position x1 and second axial positions x2 along the center axis, respectively, the following relation is 60 or smaller: |(d2−d1)/(x2−x1)|*(10{circumflex over ( )}6 mm)/d1.

A glass tube has a center axis, where for the glass tube a specific cross-sectional plane is defined which includes the center axis and which is parallel to the center axis. Within the specific cross-sectional plane, for each pair of outer diameters d1 and d2 of the glass tube at any two arbitrarily selected first axial position x1 and second axial positions x2 along the center axis, respectively, the following relation is 60 or smaller: |(d2−d1)/(x2−x1)|*(10{circumflex over ( )}6 mm)/d1.

An inlay for a sleeve shaft for collecting particles originating from a material of the sleeve shaft at least in part, at least one fluid being flowable through the sleeve shaft along an axial direction which is parallel to a main extension of the sleeve shaft, the inlay includes at least one first wall section and the inlay is inserted or insertable at least in part into the sleeve shaft such that at least one part of the first wall section has a radial distance from at least one first area of an inner surface of the sleeve shaft, and, hence, that the inlay together with the first area of the inner surface of the sleeve shaft encloses at least one volume domain, which volume domain is limited in the axial direction by a limiting element.

An inlay for a sleeve shaft for collecting particles originating from a material of the sleeve shaft at least in part, at least one fluid being flowable through the sleeve shaft along an axial direction which is parallel to a main extension of the sleeve shaft, the inlay includes at least one first wall section and the inlay is inserted or insertable at least in part into the sleeve shaft such that at least one part of the first wall section has a radial distance from at least one first area of an inner surface of the sleeve shaft, and, hence, that the inlay together with the first area of the inner surface of the sleeve shaft encloses at least one volume domain, which volume domain is limited in the axial direction by a limiting element.

Provided is a method of manufacturing a glass film, including: a conveying step of conveying an elongated glass film (G) along a longitudinal direction thereof; and a cutting step of irradiating the glass film (G) with a laser beam (L) from a laser irradiation apparatus (19) while conveying the glass film (G) through the conveying step, to thereby separate the glass film (G). The cutting step includes generating a thread-like peeled material (Ge) in a helical shape from an end portion of the separated glass film (G) in a width direction. The thread-like peeled material (Ge) has a width (W) of 180 μm or more and 300 μm or less. In addition, the thread-like peeled material (Ge) has a helical diameter (D) of 80 mm or more and 200 mm or less.

A muffle for a glass tube forming process includes an inlet end coupled to a bowl, an outlet end having an inner dimension larger than an inner dimension of the inlet end, and a sidewall extending from inlet end to the outlet end. A radial distance from a center axis of the muffle to an inner surface of the sidewall increases from the inlet end to the outlet end and the sidewall is substantially free of abrupt changes in the radial distance that produce instability regions within the muffle. The muffle includes a channel between an outer surface of a portion of the sidewall and an insulating layer disposed about the sidewall, the channel being operable to pass a heat transfer fluid into thermal communication with the sidewall to provide cooling to the muffle. Glass forming systems including the muffle and glass tube forming processes are also disclosed.

A mold includes a mold component, a plurality of ejector pins and a stop block. The mold component has a molding surface for forming a glass product and a bottom surface disposed opposite to the molding surface. The mold component defines a plurality of passing through holes through the molding surface and the bottom surface. Each ejector pin passes movably through one corresponding through hole and is configured to separate the glass product from the mold component. The stop block for forming a stop on the ejector pins disposed on one side of the bottom surface. Separates the glass product from the mold component before the glass product is completely cooled down by using the combination of the ejector pins together with the stop block, which can make the cooling of the glass product more uniform.

The invention relates to a process for preparing a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, ii.) Making a glass melt from the silicon dioxide granulate in a melting crucible, and iii.) Making a quartz glass body from at least a part of the glass melt, wherein the melting crucible is comprised in an oven and is made of at least one material comprising tungsten or molybdenum or a combination thereof. The invention further relates to a quartz glass body which can be obtained by this process. Further, the invention relates to a light guide, an illuminant and a formed body, each of which can be obtained by processing the quartz glass body further.