Abstract: The production of a quartz glass grit comprises the granulation of pyrogenetically produced silicic acid, and the formation of a SiO2 granulate and the vitrification of the SiO2 granulate using a treatment gas, which contains at least 30% by volume of helium and/or hydrogen. Said process is time consuming and cost intensive.

Abstract: A silica crucible is made in a mold cavity of the type in which ambient atmosphere can be drawn through silica grain in the cavity. In one embodiment, a silica grain layer is formed in the mold cavity and gas, which may comprise helium, nitrogen, hydrogen, or a mixture thereof, is introduced into the mold cavity. The silica grain layer is heated while substantially no ambient atmosphere is drawn through the silica grain. Thereafter, at least a portion of the silica grain layer is fused while drawing ambient atmosphere through the silica grain. The gas displaces air in the mold cavity thereby reducing nitrogen oxides and ozone.

Abstract: The production of quartz glass granules comprises the granulation of pyrogenically produced silicic acid and the formation of a SiO2 granulate (9), the drying and cleaning of the SiO2 granulate (9) by heating in an atmosphere containing halogen, and the vitrification of the SiO2 granulate (9) under a treatment gas which contains at least 30% by volume of helium and/or hydrogen. This process is time-consuming and expensive.

Abstract: In a known method for producing a mold body from synthetic quartz glass, quartz glass granules (15) are heated in an electrically heated melt container (31) to form a softened quartz glass mass (57), and the softened quartz glass mass (57) is formed to the mold body. In order to achieve an advantageous melting behavior also in continuous melting processes, it is proposed according to the invention that synthetically produced quartz glass granules (15) of granular particles are used in which helium is enclosed, wherein said quartz glass granules (15) are produced by granulating pyrogenically produced silicic acid with the formation of a SiO2 granulate (9) and subsequent vitrification of the SiO2 granulate in a rotary kiln (1), which has a rotary tube (6) which is at least partially made of a ceramic material, and under a treatment gas that contains at least 30% by volume of helium.

Abstract: The invention starts from a method for producing a crucible of quartz glass in that SiO2 inner layer granules are vitrified in a rotating melting mold, which is covered at least in part by a heat shield, in a light gas-containing atmosphere under the action of a plasma to obtain a transparent inner layer, at least part of the light gas being supplied to the melting mold through a gas inlet of the heat shield. In order to form an inner layer with a particularly low bubble content and with minimal efforts in terms of energy and material, it is proposed that in a layer forming step preceding the vitrifying step a granule layer consisting of the SiO2 inner layer granules is formed on the inner wall of the crucible, and that the plasma zone and the heat shield are movable together with the gas inlet and are moved laterally in the direction of the granule layer during the vitrifying step taken for vitrifying the granule layer.

Abstract: The production of synthetic quartz glass granules by vitrifying a free-flowing SiO2 granulate from porous granulate particles is time-consuming and expensive. The aim of the invention is to provide a method that allows a continuous and cost-effective production of dense synthetic quartz glass granules on the basis of porous SiO2 granulate. According to the invention, this is achieved by the following method steps: (a) granulating pyrogenically produced silicic acid with the formation of the SiO2 granulate made of porous granulate particles; (b) drying the SiO2 granulate; (c) cleaning the SiO2 granulate by heating in an atmosphere containing halogen in a cleaning furnace; and (d) vitrifying the cleaned SiO2 granulate by sintering in a vitrifying furnace with the formation of quartz glass granules. The drying, cleaning, and vitrifying of the SiO2 granulate are each carried out in a tary tube of a rotary tube furnace, said rotary tube rotating about a central axis.

Abstract: In a known method for producing a component with a layer of transparent quartz glass, comprising: applying particles of synthetically produced quartz glass to a base body made of quartz glass and sintering the particles so as to form the quartz glass layer. Starting therefrom, in order to permit a comparatively inexpensive and reproducible production of a component with at least one layer of transparent quartz glass that is distinguished by ultrahigh purity and the absence of bubbles, it is suggested according to the invention that at least part of the SiO2 particles should be present in the form of cylindrical fragments of quartz glass fibers having a mean diameter ranging from 0.1 mm to 3 mm and a mean length ranging from 0.5 mm to 20 mm.

Abstract: A method of producing a quartz glass crucible for pulling a single crystal comprising: providing a melting mold comprising a wall having passages between outside and inside; providing an outer layer granulation consisting of first coarser SiO2 particles and forming an outer granulation layer from the outer layer granulation on the inside of the melting mold wall; providing a barrier layer granulation consisting of second finer SiO2 particles and forming a barrier granulation layer from the barrier layer granulation on the outer granulation layer; applying a negative pressure to the outside of the melting mold wall; and heating the barrier granulation layer and the outer granulation layer with formation of a quartz glass crucible with transparent inner layer.

Abstract: In a known method for producing a component with a layer of transparent quartz glass, comprising: applying particles of synthetically produced quartz glass to a base body made of quartz glass and sintering the particles so as to form the quartz glass layer. Starting therefrom, in order to permit a comparatively inexpensive and reproducible production of a component with at least one layer of transparent quartz glass that is distinguished by ultrahigh purity and the absence of bubbles, it is suggested according to the invention that at least part of the SiO2 particles should be present in the form of cylindrical fragments of quartz glass fibers having a mean diameter ranging from 0.1 mm to 3 mm and a mean length ranging from 0.5 mm to 20 mm.

Abstract: A silica crucible is made in a mold cavity of the type in which ambient atmosphere can be drawn through silica grain in the cavity. In one embodiment, a silica grain layer is formed in the mold cavity and gas, which may comprise helium, nitrogen, hydrogen, or a mixture thereof, is introduced into the mold cavity. The silica grain layer is heated while substantially no ambient atmosphere is drawn through the silica grain. Thereafter, at least a portion of the silica grain layer is fused while drawing ambient atmosphere through the silica grain. The gas displaces air in the mold cavity thereby reducing nitrogen oxides and ozone.

Abstract: A method of producing a quartz glass crucible for pulling a single crystal comprising: providing a melting mold comprising a wall having passages between outside and inside; providing an outer layer granulation consisting of first coarser SiO2 particles and forming an outer granulation layer from the outer layer granulation on the inside of the melting mold wall; providing a barrier layer granulation consisting of second finer SiO2 particles and forming a barrier granulation layer from the barrier layer granulation on the outer granulation layer; applying a negative pressure to the outside of the melting mold wall; and heating the barrier granulation layer and the outer granulation layer with formation of a quartz glass crucible with transparent inner layer.

Abstract: The invention relates to a method for the economic production of a blank for a component made from laser-active quartz glass in any form or dimension. The method comprises the following method steps: a) preparation of a dispersion with a solids content of at least 40 wt. %, comprising SiO2 nanopowder and doping agents, including a cation of the rare earth metals and transition metals in a fluid, b) granulation by agitation of the dispersion, with removal of moisture to form a doped SiO2 granulate of spherical porous granular particles with a moisture content of less than 35 wt. % and a density of at least 0.95 g/cm3, c) drying and purification of the SiO2 granulate, by heating to a temperature of at least 1000° C. to form doped porous SiO2 grains with an OH content of less than 10 ppm and d) sintering or fusing the doped SiO2 grains in a reducing atmosphere to give the blank made from doped quartz glass.

Abstract: The invention starts from a method for producing a crucible of quartz glass in that SiO2 inner layer granules are vitrified in a rotating melting mold, which is covered at least in part by a heat shield, in a light gas-containing atmosphere under the action of a plasma to obtain a transparent inner layer, at least part of the light gas being supplied to the melting mold through a gas inlet of the heat shield. In order to form an inner layer with a particularly low bubble content and with minimal efforts in terms of energy and material, it is proposed that in a layer forming step preceding the vitrifying step a granule layer consisting of the SiO2 inner layer granules is formed on the inner wall of the crucible, and that the plasma zone and the heat shield are movable together with the gas inlet and are moved laterally in the direction of the granule layer during the vitrifying step taken for vitrifying the granule layer.

Abstract: A fence rail assembly comprises an extruded rail having a lengthwise extending slot for receiving a plurality of fasteners for attaching the rail to a plurality of pickets. The slot is designed with internal flanges adapted for engaging mating flanges on legs of a cover to be placed on the slot. The cover is sized to fit snugly at the slot opening to minimize water and debris intrusion. In one form the rail incorporates a U-shaped segment to fit over the top of the pickets.

Abstract: The invention relates to a method for the economic production of a blank for a component made from laser-active quartz glass in any form or dimension. The method comprises the following method steps: a) preparation of a dispersion with a solids content of at least 40 wt. %, comprising SiO2 nanopowder and doping agents, including a cation of the rare earth metals and transition metals in a fluid, b) granulation by agitation of the dispersion, with removal of moisture to form a doped SiO2 granulate of spherical porous granular particles with a moisture content of less than 35 wt. % and a density of at least 0.95 g/cm3, c) drying and purification of the SiO2 granulate, by heating to a temperature of at least 1000° C. to form doped porous SiO2 grains with an OH content of less than 10 ppm and d) sintering or fusing the doped SiO2 grains in a reducing atmosphere to give the blank made from doped quartz glass.

Abstract: A process for the continuous dyeing of textile materials consisting of or containing wool with reactive dyestuffs according to a steam fixation method, by impregnating the fibrous material at pH values of from 6.5 to 7.5 with an aqueous liquor containing reactive dyestuffs of the methyltaurino-ethyl-sulphone type, and fixing the dyestuff without intermediate drying of the material by treating with saturated or largely saturated steam at temperatures of from 110.degree. to 120.degree. C.

Abstract: Process for the continuous dyeing and printing of piece goods made of synthetic polyamide fibers, preferably blended with cellulosic fibers, using reactive dyestuffs according to a thermofixing method, by applying onto the textile material an aqueous padding liquor or a printing paste, which has been weakly acidified by means of a buffer system of acetic acid and an alkali metal acetate and which contains a fiber-reactive dyestuff whose reactive groups have reversibly been masked by reaction with an alkali metal salt of an N-alkyl-aminoalkyl-sulfonic acid, and after drying of the material fixing the dyestuff on the two fiber components by means of dry heat.

Abstract: Waste waters containing water glass, for example resulting from the dyeing of fabrics are purified by adding small amounts of basic nitrogen compounds, e.g. amines to the waste water and then carrying out the known flocculation process.