| 摘要 |
<p>1531742 Melting glass PILKINGTON BROS Ltd 21 Jan 1976 [31 Jan 1975] 4360/75 Heading C1M Molten glass is prepared in a tank 10 comprising a relatively wide portion 14 adjacent inlet 11, and a narrower portion 18, the wide portion 14 including melting zone 15 and refining zone 16, the narrower portion including a conditioning zone 19 which is shallower than the intermediate zone 9 which constitutes the remainder of narrow portion 18, means (e.g. barrier 34) for regulating flow of glass from wide portion 14 to narrow portion 18, return flow occurring in refining zone 16 and intermediate zone 9, but not in conditioning zone 19, and a step 33 at the start of shallow conditioning zone 19 which marks the limit of return flow through refining zone 16 towards melting zone 15. Barrier 34, which may be water-cooled, may skim off imperfect glass. Cooled stirrers 35, cooled cylinders 37 and a further cooled barrier 38 may also be provided. A soda-lime-silica glass may be cooled from, e.g., 1355-1375‹ C. at 34 to 1175-1225‹ C. at 33.</p> |
