| 摘要 |
PURPOSE:To produce uniform high-quality glass by a method wherein the surface of molten glass in glass flowing passage is covered with a cover plate of refractory material such as ceramic, the cover plate is electrically heated, and the glass flow is directly heated by electrodes provided on the side walls of the passage. CONSTITUTION:A cover plate 12 is used to cover the entire surface of flowing molten glass 13 within the conduit channel block (trough part) 11 of the forehearth except for the spout section (where orifice 9 exists). Block 11 is electrically energized from conductive wire 15 via electrode 14 so as to heat the glass 13. The electrode 14 is pressure-welded to the block 11 with spring 16 insulated with insulating glass 17. The upper space 18 is heated by electric heater 19 and is enclosed by refractory 20. Temperature detecting thermometers 23, 24 are provided to cooling zone 4 and adjusting zone 5. The cover plate 12, which is heated by transmission from the heater 19, may be replaced by direct current flow heating. The space 18 may be heated by gas instead of electric heat. Thus, the glass 13 is uniformly heated and no space is present above the glass surface and therefore furnace wall deterioration does not occur and the quality is prevented from deterioration due to mixed wall material. |
