Abstract: An electric glass-melting furnace has a cylindrical orifice block formed of a single block of refractory metal and an orifice through which molten glass flows out of the furnace. The inner end of the block extends into the melting zone portion of the furnace, while the remainder of the block extends through the furnace lining and wall, with the extreme outer tip being flush with the outer face of a water jacket which surrounds the outer end portions of the block. The block has a reduced diameter portion adjacent the outer end of the block, so that the outer end face exposes minimal surface area to outside atmosphere. The direct contact of the cooling jacket with the outer end of the block keeps the temperature of this small mass of block low enough to avoid oxidation. No protective atmosphere is required for the exterior tip of the block.

Abstract: Attempts have been made by the prior art to oscillate a veil of air entrained centrifugally spun fibers back and forth across a moving collecting surface to build a layer of fibers having uniform thickness and density. The present invention accomplishes this objective by oscillating a fiberizing rotor, preferably about an axis that runs through the bottom wall of the spinner.

Abstract: .[.Prior art high temperature electric furnaces of the type using two or more, usually three, primary electrodes positioned around an electrically conducting central outlet brought the electrodes in through a side or bottom wall of the furnace at points below the melt line causing many problems. The present invention provides a primary electrode arrangement for such melting furnaces wherein the primary electrodes do not pass through the wall or bottom of the furnace below the melt line, but instead enter the furnace over the top of the melt line and then protrude through the top surface of the melt. The primary electrodes of the present invention are provided with means for preventing wear and deterioration at the interface between the top surface of the melt and the unmelted batch and/or the oxidizing air atmosphere surrounding the top of the furnace. The improved furnace of the present invention does not require the use of a purging neutral or reducing atmosphere to protect the primary electrodes..]. .Iadd.