A large melting furnace suitable for borosilicate glass. The melting furnace includes a melting area, a reinforcing area, an ascending area and a clarifying area. The melting area includes no furnace crown, a surface of molten glass in the melting area is not covered by any wall and exposed for feeding. The reinforcing area includes a first furnace crown, the first furnace crown includes a first partition wall and a second partition wall, and the reinforcing area and the melting area are separated by the first partition wall, and a lower end of the first partition wall goes deep below a surface of molten glass but is not in contact with a bottom of the melting furnace, so as to guarantee that the molten glass in the melting area and the reinforcing area is interconnected.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.

Systems and methods for controlling the flow of vitrified material. In at least some embodiments, a vitrified material control system comprises a melt chamber (8) configured to contain a molten material (27) during operation of the control system; a siphon valve (11) configured to facilitate a flow of the molten material from the melt chamber; and a vacuum-generation system (26, 15, 16) configured to controllably deliver a vacuum to the molten material in the melt chamber and to thereby regulate a flow of the molten material from the melt chamber. In other embodiments, methods of controlling a flow of molten vitrified material from a heating device are disclosed. The methods may include, for example, applying a vacuum to the molten material to control a dwell time of the molten material in a vessel of the heating device and regulating the vacuum based on a measured temperature of the molten material.