GB597842A - Improvements in or relating to the making of glass - Google Patents

Abstract

597,842. Glass-melting furnaces. SOC. ANON. DES MANUFACTURES DES GLACES ET PRODUITS CHIMIQUES DE ST. - GOBAIN, CHAUNY, & CIREY. Sept. 3, 1945, No. 22575. Convention date, April 13, 1944. [Class 51 (ii)] [Also in Groups XI and XXIII] To ensure that the bubbly glass passing from the melting zone of a furnace to the top of a collected body of fined glass in a separate fining zone shall be at a sufficient temperature to prevent it sinking through the already fined glass until it has itself been fined, the glass is heated during such passage. The temperature in the melting zone need therefore be only sufficient just to melt the glass. The fining is effected by the passage of current between electrodes immersed in the top of the molten glass in the fining zone which is fed from the top of the melting zone as in Specification 597,838. Several arrangements of intermediate heating means are described comprising electrodes either in the melting zone immediately in front of the passage to the fining zone, or actually in such passage or, as shown, in a second stop 12 between such passage 4 and the actual fining zone 2. The intermediate heating may, however, be effected by gas. When the melting zone 1 is heated by gas the hot exhaust may be passed through the double roof 14, 15 of the fining zone.