Abstract: A charged glass raw material B is melted in a melting tank 10 by heating with a burner 31 and by heating with electrodes 12, to form molten glass G. Then, the molten glass G flows into a tank additionally provided as a noble gas dissolving tank 20 through a throat 40. The noble gas dissolving tank 20 is provided with a noble gas dissolving device 53, and the noble gas dissolving device 53 is provided with sixteen noble gas inlets 22 for introducing a helium or neon gas supplied to a hearth through heat resistant gas introduction tubes 21 into the noble gas dissolving tank 20. Bubbles of a helium gas A having a purity of 99% are blown out from the noble gas inlets 22 in volumes such that the bubbles have an average diameter of 80 mm or less in the molten glass G.

Abstract: A charged glass raw material B is melted in a melting tank 10 by heating with a burner 31 and by heating with electrodes 12, to form molten glass G. Then, the molten glass G flows into a tank additionally provided as a noble gas dissolving tank 20 through a throat 40. The noble gas dissolving tank 20 is provided with a noble gas dissolving device 53, and the noble gas dissolving device 53 is provided with sixteen noble gas inlets 22 for introducing a helium or neon gas supplied to a hearth through heat resistant gas introduction tubes 21 into the noble gas dissolving tank 20. Bubbles of a helium gas A having a purity of 99% are blown out from the noble gas inlets 22 in volumes such that the bubbles have an average diameter of 80 mm or less in the molten glass G.

Abstract: Disclosed is a burner for burning liquid fuel that is able to obtain a long flame in which the proportion of the luminous flame portion is large, and thereby particularly effective for radiant heat transfer. This liquid fuel burner is composed of a fuel feed pipe (4) having a fuel spray nozzle (3) at its distal end, a combustion-assisting gas feed pipe (6) provided concentrically on the outside of the fuel feed pipe (4) to form a combustion-assisting gas passage (5), and an orifice member (7) arranged within the above-mentioned fuel feed pipe (4) at an interval from the distal end of the fuel feed pipe (4). In addition, the orifice (9) of the orifice member (7) and the fuel spray nozzle (3) of the above-mentioned fuel feed pipe (4) are mutually eccentric.