| 摘要 |
1,230,074. Glass manufacture. PILKINGTON BROS. Ltd., C. E. SMITH, and I. W. MCKITTRICK. 10 May, 1968 [25 May, 1967], No. 24344/67. Heading ClM. In the manufacture of flat glass by the " float " process the tank structure is lined with an alumino-silicate refractory comprising 40 to 80% by weight alumina, and from 20 to 55% by weight silica and having evenly distributed pores of uniform size distribution linear over the range 0.02 to 100 Á. It is preferred that the refractory contains not more than 1% of alkali, expressed as oxide and less than 1%, preferably less than 0.5%, of iron oxide expressed as Fe 2 O 3 . As shown the lining 9-12 of the side and end walls extends above the surface of the level of molten metal. The refractory chosen does not exhibit undesirable glass forming properties with elements present in the molten metal bath, e.g. sodium which has entered from the glass. The porous refractory is advantageous when a negative pressure is applied to an interspace between the lining blocks 9-12 and the outer casing 5-8 of the tank. |
