| 摘要 |
<PICT:1023236/C1/1> To improve the annealing of flat glass, particularly when drawn upwardly through an annealing lake, at the beginning of the annealing zone, the marginal portions 17 of the ribbon 2 are heated up to a temperature towards that of the central portion and above the strain point of the glass ribbon until the central portion cools to near the strain point, both marginal and central portions then being allowed to cool below the strain point. Blowing tubes 18 provided with hot air from burner chambers 19 blow directly against the edges 17 or may, Fig. 4, be divided at 25 to blow air either side of the glass edge. Baffles 20, 21, 22 and further hot air manifolds 23, Figs. 1, 2, (not shown) may be provided as in Specification 1,023,235. |
