Abstract: A method for controlling the foam produced when a molten material encounters reduced pressure in a vacuum chamber includes passing the molten material through an aging zone in the vacuum chamber in which the molten material is allowed to drain from between the bubbles of the foam and then collapsing the bubbles of the drained foam.

Abstract: A method for controlling the foam produced when a molten material encounters reduced pressure in a vacuum chamber includes passing the molten material through an aging zone in the vacuum chamber in which the molten material is allowed to drain from between the bubbles of the foam and then collapsing the bubbles of the drained foam.

Abstract: A method for controlling the foam produced when a molten material encounters reduced pressure in a vacuum chamber includes passing the molten material through an aging zone in the vacuum chamber in which the molten material is allowed to drain from between the bubbles of the foam and then collapsing the bubbles of the drained foam.

Abstract: A tubing system for conveying a molten material through a vacuum housing includes a tubing having a plurality of convolutions which compress as the tubing expands. A plurality of projections disposed along a length of the tubing carries the electrical current which heats the tubing. A plurality of refractory insulation bricks are stacked between the projections. A first seal flange is coupled to an inlet end of the tubing, and a second seal flange is coupled to an outlet end of the tubing. Each seal flange includes a metal seal ring which is adapted to be coupled to the base of the vacuum housing so as to make a sealed contact with the base of the vacuum housing. Each seal flange also includes a refractory seal block which transfers the expansion force of the tubing to the metal seal ring and, thereby, causes the convolutions to compress.

Abstract: Process and apparatus are disclosed for delivering molten thermoplastic material from one chamber to another through a throat in a refractory wall separating said chambers. A refractory metal conduit is positioned within said refractory throat below the level of the floor of said chambers, and standpipes at each end of said conduit extending above the level of said floors, create stagnant thermoplastic material about the conduit so as to prevent corrosion products from flowing away from about the conduit and thereby also preventing fresh thermoplastic from replacing it. The stagnant material becomes enriched with corrosion products, which with the absence of flow retards further corrosion of the refractory about the conduit.

Abstract: There is disclosed a glass melting furnace having various forms of baffles located within the melt for dividing the furnace into zones and creating extended flow paths within the furnace for increasing the minimum residence time of the glass within the furnace and thereby improving glass melting and refining.

Abstract: An electric melting furnace is described for melting high electrical resistivity glass, such as E-glass, within a melting chamber surrounded by a relatively low electrically resistivity refractory, such as chromic oxide refractory, by utilizing interconnected peripherally positioned batch electrodes at substantially the same potential as the chromic oxide walls and centrally positioned electrodes which are immersed a greater distance than the batch electrodes. A quiescent zone is formed adjacent a lower portion of the melting chamber and the batch blanket and effective hydrostatic head of the molten bath are adjusted by controlling the immersion of the batch electrodes within the molten bath.

Abstract: Electrically energizable heating means are disclosed for supplying heat to a bottom portion of a melting furnace having a metal lined refractory vessel, wherein the heating means are in the form of electrodes or resistance heaters which are protected from the body of the melt by a shroud forming a portion of the metal liner for the refractory vessel, and such heating elements are raised above the bottom of the refractory vessel to prevent the corrosion thereof due to the heat produced by the heating units.

Abstract: A glass melting furnace is disclosed having a refractory melting vessel provided with a protective liner formed of an oxidizable refractory metal such as molybdenum, wherein the liner projects upwardly within a molten bath contained within the vessel and through its fusion line into a batch blanket retained thereabove which is low in carbonates. The upper end of the liner is provided with a seal to prevent the flow of batch material between the liner and the refractory vessel and thereby prevent contamination of material behind the liner and reduce corrosion of the refractory vessel.

Abstract: A method and apparatus for melting thermoplastic material is disclosed utilizing, in a preferred embodiment, a vessel having a bottom wall and upstanding sidewalls. A protective liner for the vessel is provided, being formed of corrosion resistant material. The furnace may include both through-the-batch and floor electrodes, and also hot spot fining to a conductive outlet channel.A method is set forth for operating the furnace described herein utilizing symmetrical, below the batch heat dissipation for accelerated melting. In order to protect the liner, which in some instances may be fabricated from an oxidizable refractory metal, start-up burners are operated under a reduced oxygen supply.

Abstract: In a glass-melting furnace, electrodes are inserted through the batch in symmetrical locations spaced from sidewalls of the furnace. Melting and refining take place in relatively narrow bands below the batch.

Abstract: A method and apparatus for melting thermoplastic material is disclosed utilizing, in a preferred embodiment, a vessel having a bottom wall and upstanding sidewalls. A protective liner for the vessel is provided, being formed of corrosion resistant material. The furnace may include both through-the-batch and floor electrodes, and also hot spot fining to a conductive outlet channel.A method is set forth for operating the furnace described herein utilizing symmetrical, below the batch heat dissipation for accelerated melting. In order to protect the liner, which in some instances may be fabricated from an oxidizable refractory metal, start-up burners are operated under a reduced oxygen supply.