Described herein are systems and methods for heating and melting glass through the use of induction based heating and methods for forming a fiberglass strand. An exemplary induction melter system for melting glass can include a melting vessel and a heated drain. The melting vessel can include a crucible, a first induction coil positioned around at least a portion of the crucible, and a first electromagnetic current generator coupled to the first induction coil. The heated drain can be coupled to the melting vessel, and the heated drain can include a drain tube, a second induction coil positioned around at least a portion of the drain tube, and a second electromagnetic current generator coupled to the second induction coil.

Submerged combustion glass manufacturing systems and methods include a melter having a floor, a roof, a wall structure connecting the floor and roof, and one or more submerged combustion burners mounted in the floor, roof, and/or wall structure discharging combustion products including water vapor under a level of material being melted in the melter and create turbulent conditions in the material. The floor, roof, or wall structure may include fluid-cooled refractory material and an optional metallic external shell, or the metallic shell may include coolant passages. One or more conduits drain water condensed from the water vapor from regions of refractory material substantially saturated with the water, and/or from burner supports.

An apparatus for manufacturing glass includes a furnace. A doghouse of the furnace receives and melts solid-glass forming material using one or more submerged combustion burners. An elongated tank positioned downstream of the doghouse includes a melting chamber, a refining chamber, and a thermal conditioning. The melting chamber has in inlet through which molten glass is received from the doghouse. The refining chamber is positioned downstream of the melting chamber and receives molten glass from the melting chamber. The thermal conditioning chamber is positioned downstream of the refining chamber and receives molten glass from the refining chamber. Additionally, the thermal conditioning chamber delivers molten glass to a glass forming machine.

A glass manufacturing apparatus includes a dissolving vessel configured to dissolve a glass raw material to produce a molten glass, a forming vessel configured to form the molten glass into a predetermined shape, and glass supply tubes configured to convey the molten glass from the dissolving vessel to the forming vessel. The glass supply tubes each include a tube body, a flange portion, which is arranged in an outer circumferential portion of the tube body and has first and second parts, an electrode portion arranged in the first part, and a temperature difference setting portion configured to cause a temperature difference between the first and second parts. The temperature difference setting portion sets a temperature of the first part to be higher than that of the second part.

A method for reconditioning a glass manufacturing system includes establishing a reducing atmosphere in a glass melting vessel and draining a glass melt composition from the melting vessel while the reducing atmosphere is in the vessel. The pressure of the reducing atmosphere is greater than the pressure of the atmosphere surrounding the melting vessel and the reducing atmosphere is established by operating at least one combustion burner in the melting vessel in a fuel-rich condition.

An apparatus and method of refining molten glass are disclosed. An upstream vessel contains molten glass, a downstream vessel is arranged downstream of the upstream vessel, and vacuum refining vessels are located between the upstream vessel and the downstream vessel and are in separate, alternating fluid communication with the upstream vessel and in separate, alternating fluid communication with the downstream vessel.

A gradient fining tank and a method of operating the tank to refine foamy molten glass is disclosed. The gradient fining tank includes a floor, a roof, and two laterally-spaced sidewalls that at least partially define an interior chamber of the tank. The floor of the tank is profiled to provide the tank with an extended shallow portion that defines an inlet to the interior chamber and a deep holding portion that defines an outlet from the interior chamber. An entry section of the floor provides the extended shallow portion of the tank and a transition section and exit section of the floor provide the deep holding portion. A depth of the interior chamber at an outlet end of the deep holding portion is greater than a depth of the interior chamber at the outlet end of the extended shallow portion.

An apparatus for manufacturing glass includes a furnace. A doghouse of the furnace receives and melts solid-glass forming material using one or more submerged combustion burners. An elongated tank positioned downstream of the doghouse includes a melting chamber, a refining chamber, and a thermal conditioning. The melting chamber has in inlet through which molten glass is received from the doghouse. The refining chamber is positioned downstream of the melting chamber and receives molten glass from the melting chamber. The thermal conditioning chamber is positioned downstream of the refining chamber and receives molten glass from the refining chamber. Additionally, the thermal conditioning chamber delivers molten glass to a glass forming machine.

An apparatus and methods of refining glass, in a multi-stage, downwardly cascading manner, include a melting chamber housing molten glass and having an outlet, a first refining chamber downstream from the melting chamber and having a first outlet and a first inlet below the outlet of the melting chamber, and a second refining chamber downstream from the first refining chamber and having a second outlet and a second inlet below the first outlet of the first refining chamber. The first refining chamber has a first negative pressure and the second refining chamber has a second negative pressure.

A gradient fining tank and a method of operating the tank to refine foamy molten glass is disclosed. The gradient fining tank includes a floor, a roof, and two laterally-spaced sidewalls that at least partially define an interior chamber of the tank. The floor of the tank is profiled to provide the tank with an extended shallow portion that defines an inlet to the interior chamber and a deep holding portion that defines an outlet from the interior chamber. An entry section of the floor provides the extended shallow portion of the tank and a transition section and exit section of the floor provide the deep holding portion. A depth of the interior chamber at an outlet end of the deep holding portion is greater than a depth of the interior chamber at the outlet end of the extended shallow portion.