Abstract:
A process for producing tubes or rods is provided. The process includes providing a settable liquid and producing a strand by drawing the liquid from a nozzle in a drawing direction. The result of this is that the settable liquid emerges through an annular gap formed by the nozzle with the desired production throughput at the temperature which is above the devitrification temperature. The settable liquid cools as it flows down an outer and/or an inner surface of a displacement body so that, by the end of the displacement body, the settable liquid has a sufficiently high viscosity to be drawn in stable form at the desired production throughout without flowing more quickly than the drawing rate as a result of its own weight.
Abstract:
The invention includes a method and an arrangement for influencing the flow of glass melts in a controlled way during the transfer from the melting furnace to a processing process. The simultaneous generation of electric and magnetic fields generates a force in the glass melt which boosts or inhibits the melt flow and acts substantially in the same direction as or in the opposite direction to the main direction of flow. It is in this way possible to control the melt flow without affecting the temperature of the melt. Consequently, the invention is suitable in particular for the accurately controllable feeding of a homogeneous glass melt to a glass production process.
Abstract:
The stepped optical fiber has a core glass member and a surrounding cladding glass member. It has a high numerical aperture (NA)≧0.50. The core glass member preferably has a zinc-containing composition including, in % by weight, SiO2, 42 to 53; ZnO, 16 to 38; PbO, 1 to 20; Na2O,
Abstract translation:阶梯式光纤具有芯玻璃构件和周围的包层玻璃构件。 它具有高数值孔径(NA)> = 0.50。 核心玻璃构件优选具有含锌组合物,其包含以重量%计的SiO 2,42至53; ZnO,16〜38; PbO,1〜20; Na 2 O,<14; K 2 O,<12; ZnO和PbO> = 30之和,Na 2 O 2和K 2 O 2之和为> = 2。 与该芯玻璃相容的包层玻璃组合物以重量%计含有SiO 2,60〜72, B 2 O 3,<20; AL 2 O 3,<10; NA 2 O,<18; 和K 2 O,<15。 所得到的光纤具有低衰减,非常中性的色彩传输和低制造成本。 其他包覆玻璃组合物导致在芯玻璃边界层处具有太多结晶的相当差的性质。 还准备了具有甚至更低孔径值> = 0.48的芯玻璃的环保无铅实施例。