STUDY OF GAS-ELECTRIC BOTTLE GLASS MAKING O F

bottle-making machines R-7 have been installed with the furnace. One of the means of raising the specific productivity of tank furnaces is the high-temperature glassmaking. However, increasing the temperature of the flame space to 1580~176 by gas burning would have necessitated considerable constructional changes in different furnace elements and substitution of a large portion of the upper refractory lining of the furnace by refractories of higher glass-reslstance and thermal stability. Moreover, it would have been necessary to reconstruct the exhaust channels, which cannot be done in an operating shop. In view of this it was decided to increase the productivity of a tank furnace by introducing an additional quantity of heat directlytothe molten glass. Simultaneously it was planned to investigate the possibility of reducing the thermal stresses in the molten glass surface with the given scheme of electric preheating and normalizing the ratio of charge to cullet. The tank furnace with electric preheating and churning arrangements is a regenerative one with transverse direction of the flame. The depth of the basin is 900 ram. The productivity of the furnace with gas heating is 130 tens/day and the rate of extraction of molten glass is 1411 kg/(m 2 �9 day). The furnace (Fig. 1) is intended for making dark-green glass of the following composition: 68.4% SIO2, 4.5% A1203, 6.3% CaO, 3.9~ MgO, 14.5% Na20 , 1.2% Mn304, 1.4% Fe203, and 0.2% SO 3 by weight. The ratio of charge to culletwas 65.5 : 34.5. The work for mastering the technology of bottle glassmaking by gas-electric heating was envisaged to be completed in two phases: in the first phase the technology of glassmaking by gas-electric heating would be developed by introducing 800-1020 kW electric power in the molten glass and in the second phase the productivity of the furnace would be raised by putting 1400 kW in the molten glass. The mastering of gas-electric making of bottle glass was preceeded by scientific-resea rch works, which were aimed at obtaining data on the technology of gas-electric making of bottl~ glass. In addition, the effect of position of electrodes and churning nozzles on the hydrodynamics of molten glass and productivity of the furnace was studied by the method of model study [1]. On the basis of the model study the optimum position of the electrodes was selected in combination with churning [2], which was incorporated in the design of the gas-electric furnace under consideration. Nine molybdenum electrodes, each of 50-ram diameter , were installed vertically. The effective length of the electrodes was 800 mm. The electrodes were located in two rows in a chessboard pattern. The schematic layout of the electrodes is presented in Fig. 1. With the above-mentioned arrangement of electrodes the rising stream of molten glass forms at a distance of 500-600 mm from the second row of electrodes (from the drawing side). In this arrangement Gusev Branch of the State Scientific-Resea rch Institute of Glass. Konstantinovsk Glass Works.