Abstract: An apparatus for producing a glass tube includes: a drawing head including a glass inlet and a glass outlet, the drawing head having a total height h and an inner diameter d, a ratio h/d being from 2/1 to 7/1; and a drawing needle. A distance a between the drawing needle and an inner wall of the drawing head is in a range from 40 to 300 mm.

Abstract: A glass composition and its use for producing glass tubes is provided. The glass tubes having the provided composition are particularly suitable for the outer tubes of fluorescent lamps in the case of which a phosphor layer is baked at temperatures of up to 700° C. The tubes composed of the glass of the provided composition have a lower tendency to deform or stick together when processed at high temperatures. To obtain the observed effects, the molar ratio of Na2O/(Na2O+K2O), inter alia, is greater than 0.4 and not more than 0.72.

Abstract: The invention relates to an alumino-silicate glass which has a thermal expansion coefficient in the range of 8 to 10×10?6/K in a temperature range of 20 to 300° C., a transformation temperature Tg in a range of 580° C. to 640° C., and a processing temperature VA in a range of 1065° C. to 1140° C. and which can therefore be used as an alternative for soda lime glasses. An object of the invention is also the use of the inventive glasses in applications where a high temperature stability of the glasses is advantageous, in particular as substrate glass, superstrate glass and/or cover glass in the field of semiconductor technology, preferably for Cd—Te or for CIS or CIGS photovoltaic applications and for other applications in solar technology.

Abstract: A glass composition and its use for producing glass tubes is provided. The glass tubes having the provided composition are particularly suitable for the outer tubes of fluorescent lamps in the case of which a phosphor layer is baked at temperatures of up to 700° C. The tubes composed of the glass of the provided composition have a lower tendency to deform or stick together when processed at high temperatures. To obtain the observed effects, the molar ratio of Na2O/(Na2O+K2O), inter alia, is greater than 0.4 and not more than 0.72.

Abstract: The invention relates to an alumino-silicate glass which has a thermal expansion coefficient in the range of 8 to 10×10?6/K in a temperature range of 20 to 300° C., a transformation temperature Tg in a range of 580° C. to 640° C., and a processing temperature VA in a range of 1065° C. to 1140° C. and which can therefore be used as an alternative for soda lime glasses. An object of the invention is also the use of the inventive glasses in applications where a high temperature stability of the glasses is advantageous, in particular as substrate glass, superstrate glass and/or cover glass in the field of semiconductor technology, preferably for Cd—Te or for CIS or CIGS photovoltaic applications and for other applications in solar technology.

Abstract: The alkaline earth metal aluminosilicate glass for light bulbs with molybdenum parts has a composition (in percent by weight on an oxide basis) of SiO2, 56-60; Al2O3, 17-18; B2O3, 0.5-2; MgO, 0.5-2; CaO, >14-15.5; SrO, 0-3; BaO, 6-8; ZrO2, 0-5; CeO2, 0-0.1 and TiO2, 0-0.5.

Abstract: The glass-metal bond for a tube collector includes a glass tube and metal part bonded to the glass tube. In order to match the thermal expansion properties, the glass tube has the following composition: SiO2, 73-77 wt. %; B2O3, 6-<8 wt. %; Al2O3, 6-6.5 wt. %; Na2O, 5.5-7 wt. %; K2O, 1-3 wt. %; CaO, 0.5-3.2 wt. %; MgO, 0-2 wt. %; Fe2O3, 50-150 ppm; and TiO2 0-<100 ppm. The ratio of the sum of the alkaline-earth metal oxides (in mol %) to the sum of the alkali metal oxides (in mol %) is ?0.6. The metal part is preferably made of metal material no. 1.3981 according to DIN 17745. The glass composition itself is also part of the invention.

Abstract: The alkaline earth metal aluminosilicate glass for light bulbs with molybdenum parts has a composition (in percent by weight on an oxide basis) of SiO2, 56-60; Al2O3, 17-18; B2O3, 0.5-2; MgO, 0.5-2; CaO, >14-15.5; SrO, 0-3; BaO, 6-8; ZrO2, 0-5; CeO2, 0-0.1 and TiO2, 0-0.5.

Abstract: The glass-metal bond for a tube collector includes a glass tube and metal part bonded to the glass tube. In order to match the thermal expansion properties, the glass tube has the following composition: SiO2, 73-77 wt. %; B2O3, 6-<8 wt. %; Al2O3, 6-6.5 wt. %; Na2O, 5.5-7 wt. %; K2O, 1-3 wt. %; CaO, 0.5-3.2 wt. %; MgO, 0-2 wt. %; Fe2O3, 50-150 ppm; and TiO2 0-<100 ppm. The ratio of the sum of the alkaline-earth metal oxides (in mol %) to the sum of the alkali metal oxides (in mol %) is ?0.6. The metal part is preferably made of metal material no. 1.3981 according to DIN 17745. The glass composition itself is also part of the invention.

Abstract: The present invention relates to a device and method for transporting, homogenizing or conditioning of glass melts or glass ceramic melts and is distinguished in that the new formation of bubbles after refining is at least reduced. The new formation of bubbles on the surfaces of components that are in contact with the melt is at least reduced by means of a layer having iridium as a material.

Abstract: A device for the production of a glass rod is provided. The device has a Danner blowpipe constructed to avoid problems attributed to different heat expansion coefficients of the participating materials. The Danner blowpipe has an outer metal jacket surrounding a ceramic body and defines a supply end and a discharge end of the blowpipe. A clamping plate is provided at both the supply and discharge ends. The clamping plate on the discharge end is rigidly joined with a shaft and engages the outer metal jacket at the discharge end. The clamping plate on the supply end is joined in an axially displaceable manner on the shaft, which is rigidly joined with a pressure plate against displacement in an axial direction. A pressure spring is disposed between the pressure plate and the clamping plate on the supply end to urge the plates away from one another.

Abstract: The invention relates to a method for manufacturing a glass tube with a coated inner surface by drawing a glass melt (5) to a bag (8) of softened glass and hot forming to a glass tube (9). During the process a substance is introduced into the bag (8) of softened glass. According to the invention the substance is introduced as an aerosol and the inner surface is coated by means of the substance during the hot forming. The method permits economical internal coating with a continuous glass drawing method. The use of aggressive chemical substances for internal coating can be dispensed with according to the invention. As a result, for example, internally coated glass tubes with improved hydrolytic resistance can be manufactured. The invention also relates to a suitable apparatus for manufacturing internally coated glass tubes and the use of glass tubes manufactured by this means for further processing to a hollow, internally coated formed glass body, for example, as primary packaging in the pharmaceuticals field.

Abstract: The invention concerns a device for supporting a horizontal guided, continuous glass strand; with a number of supporting blocks, which each exhibits a supporting area, facing the glass strand; the individual supporting block in the area of the supporting area is made from a porous, gas-impermeable diaphragm body; the diaphragm body is connected to a source of compressed gas for conveying gas through the supporting area.

Abstract: The double-walled noble metal duct (1) for conducting a glass melt has an outer noble metal pipe (1b) and an inner noble metal pipe (1a) extending within the outer pipe, so that an inner space (21) is formed within the inner pipe and an intermediate space (23) is formed between the inner pipe (1a) and the outer pipe (1b). The intermediate space is completely filled with glass melt when the double-walled noble metal duct conducts the glass melt, when the outer pipe (1b) has an exhaust vent (4). The outer pipe (1b) also has a bottom outlet (7) communicating with the intermediate space for removal of oxygen bubbles formed on the outer wall. The noble metal duct can be used in glass conditioning and in the manufacture of glass articles that are devoid of polyvalent ions.

Abstract: The sleeve-type glass melt agitator has a rotatable cylindrical sleeve provided with outwardly protruding vane elements and through-going openings in its outer cylindrical surface to stir the glass melt when the sleeve is rotated. The sleeve type agitator is arranged vertically in a glass melt feed channel in a glass melt feed system for making glass tubes or pipes according to the Vello or down-drawn process. During formation of glass tubes or pipes from the glass melt the sleeve-type agitator is rotated as the glass melt flows downward to prevent formation of schlieren in the glass melt, which causes glass material losses.

Abstract: The present invention relates to a method of treating a component which is intended for a facility for producing or preparing glass melts and has surfaces which are made of noble metal and come into contact with glass melts during operation.

Abstract: The invention relates to a device for producing a glass rod. The device comprises a Danner blowpipe (1); a nozzle for applying stream of glass to the surface of the Danner blowpipe (1) at one end of said blowpipe (supply end) at a relatively high temperature in order to form a glass film, which is removed at the other end (discharge end) in the form of a bulb at low speed. According to the invention, the device is characterised as follows: the Danner blowpipe (1) is constructed as follows: the peripheral wall consists of an external metal jacket (2) and a ceramic body (3) surrounded by said jacket; a respective clamping plate (6.1, 6.2) is provided at the supply end and at the discharge end; the discharge-end clamping plate (6.2) is connected in a fixed manner to the shaft (6); the supply-end clamping plate (6.

Abstract: A tube blank is disclosed for producing glass receptacles, in particular glass tube vials, glass ampules, or glass syringes, particularly those suitable for pharmaceutical applications, having a tube wall, including two end regions—a first end region and the second end region—the first end region being sealed to form a floor and a ventilation hole being introduced into the tube wall in the region of the end region, distinguished in that the tube end characterizing the second end region has an opening.

Abstract: The invention relates to a process for the production of internally-hardened glass tubes, in which in a tube-drawing process for the production of glass tubes that is known in the art, a coated drawing tool, for example in the process according to Danner a coated mandrel or in the process according to Vello or in A-drawing process a coated needle, is used, whose coating releases coating material upon contact with the inside surface of the tube that is produced and accumulates on the inside glass surface. The chemical resistance is increased by this internal hardening. The invention also relates to devices for implementing this process and uses of the tubes that are produced according to these processes.

Abstract: The double-walled noble metal duct (1) for conducting a glass melt has an outer noble metal pipe (1b) and an inner noble metal pipe (1a) extending within the outer pipe, so that an inner space (21) is formed within the inner pipe and an intermediate space (23) is formed between the inner pipe (1a) and the outer pipe (1b). The intermediate space is completely filled with glass melt when the double-walled noble metal duct conducts the glass melt when the outer pipe (1b) has an exhaust vent (4). The outer pipe (1b) also has a bottom outlet (7) communicating with the intermediate space for removal of oxygen bubbles formed on the outer wall. The noble metal duct can be used in glass conditioning and in the manufacture of glass articles that have polyvalent ion vacancies.