A radiation pumped heater includes a ceramic substrate which is heated by a laser beam to a steady state temperature. An optical fiber is heated by conduction and radiation emitted from the ceramic substrate.

An apparatus and related process for producing a high-strength weld between two glass components. Chucks clamp and move respective first ends of the glass components toward each other inside an enclosure, where the second ends are heated, softened, and welded together in a weld zone. The enclosure has layers of stacked quartz glass bricks and allows the weld zone to cool slowly and avoid stress. A propane quartz melting torch directs a flame inside the enclosure and toward the second ends as the glass components move toward each other. The flame softens the second ends and creates substantially smooth polished surfaces in the weld zone having an increased hydroxide content. At least 80% of the weld zone has a hydroxide content greater than about 10 ppm average in a 10 m depth from the surface and the tensile strength of the weld zone is above about 10 MPa.

A molding tool, a method, and an apparatus for hot forming of glass are provided that provide glass products used for pharmaceutical packaging. The molding tool includes a forming mandrel for reshaping at least a portion of a heated region of a glass precursor. The mandrel has a temperature-stable core material and an alloying element. The core material is made of precious metals, in particular of platinum group elements, and the further alloying element is made of one of tungsten, zirconium, rhodium, molybdenum, and rhenium.

A molding tool, a method, and an apparatus for hot forming of glass are provided that provide glass products used for pharmaceutical packaging. The molding tool includes a forming mandrel for reshaping at least a portion of a heated region of a glass precursor. The mandrel has a temperature-stable core material and an alloying element. The core material is made of precious metals, in particular of platinum group elements, and the further alloying element is made of one of tungsten, zirconium, rhodium, molybdenum, and rhenium.

The invention relates to a method for producing glass tubes with a cross section of a noncircular form by reshaping. This method includes at least providing a glass tube, heating the glass tube, providing at least one reshaping tool, which has a forming body with a forming area for reshaping the heated glass tube, the forming body including at least one open-porous material, setting a gas pressure in the interior of the reshaping tool lower than 90 kPa, so that a negative pressure is produced on the forming area, and reshaping the heated glass tube by applying a compressive force perpendicularly to the longitudinal axis of the glass tube, the compressive force being generated by the reshaping tool and being applied to the outer surface of the glass tube, and the outer surface of the glass tube being fixed by the negative pressure.

The invention relates to a method for producing glass tubes with a cross section of a noncircular form by reshaping. This method includes at least providing a glass tube, heating the glass tube, providing at least one reshaping tool, which has a forming body with a forming area for reshaping the heated glass tube, the forming body including at least one open-porous material, setting a gas pressure in the interior of the reshaping tool lower than 90 kPa, so that a negative pressure is produced on the forming area, and reshaping the heated glass tube by applying a compressive force perpendicularly to the longitudinal axis of the glass tube, the compressive force being generated by the reshaping tool and being applied to the outer surface of the glass tube, and the outer surface of the glass tube being fixed by the negative pressure.

A known method for homogenizing glass includes the following steps: providing a cylindrical blank composed of the glass, having a cylindrical outer surface which extends between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and moving the shear zone along the longitudinal axis of the blank. To reduce the risk of cracks and fractures during homogenizing, it is proposed that a thermal radiation dissipator is used that at least partially surrounds the shear zone, the lateral dimension of which in the direction of the longitudinal axis of the blank is greater than the shear zone and smaller than the length of the blank, the thermal radiation dissipator being moved synchronously with the shear zone along the longitudinal axis of the blank.

A glass rod manufacturing device includes: a holding portion configured to hold one end of a starting rod; a heating portion configured to heat a bent portion; and a centering jig configured to apply a force in a first direction intersecting an axis to a part of the starting rod that whirls between the bent portion and another end of the starting rod due to rotation of the starting rod about an axis. The centering jig includes: an abutment portion configured to abut against the part; an elastic displacement portion configured to elastically displace the abutment portion in the first direction according to a run-out deviation of whirl of the part; and a slide portion configured to slide the abutment portion in a second direction intersecting the axis and the first direction according to the run-out deviation of whirl of the part.

A glass rod manufacturing device includes: a holding portion configured to hold one end of a starting rod; a heating portion configured to heat a bent portion; and a centering jig configured to apply a force in a first direction intersecting an axis to a part of the starting rod that whirls between the bent portion and another end of the starting rod due to rotation of the starting rod about an axis. The centering jig includes: an abutment portion configured to abut against the part; an elastic displacement portion configured to elastically displace the abutment portion in the first direction according to a run-out deviation of whirl of the part; and a slide portion configured to slide the abutment portion in a second direction intersecting the axis and the first direction according to the run-out deviation of whirl of the part.

A method and apparatus are provided for producing a tube of glass by zonewise heating and softening of a hollow cylinder by a movable heating zone while rotating about its rotation axis. The glass tube is continuously formed by radial expansion of the softened region under action of centrifugal force and/or internal overpressure applied in the hollow-cylinder bore. The method and apparatus make it possible to deform the hollow cylinder in a single or a small number of forming steps into a glass tube having a larger outer diameter and high dimensional accuracy by determining a circumferential position at which the wall thickness is comparatively small, and during heating and softening of the rotating hollow cylinder a coolant is dispensed from a coolant source onto the deformation zone only when or predominantly when the circumferential position having the comparatively small wall thickness passes the coolant source.