Ppg Industries, Inc.

John E Sensi

Gerald E Kunkle

Yih-Wan Tsai

Joseph A Gulotta

Vincent I Henry

Leonard A Knavish

Richard L Cerutti

In a method of making glass or the like, wherein the batch materials are liquefied in a distinct zone from the refiner, the liquefied material is heated in an intermediate stage before being fed to the refiner. The heating entails intensified flames that impinge the surface to provide homogenization and a barrier to surface flow of low density material.

Heating and agitating method for multi-stage melting and refining of

Patterned float glass is produced without distorting patterns imparted to the surface by forming the glass by a process that avoids deformation of the glass subsequent to the pattern imparting step.

Patterned float glass method

Delivery of molten glass to a flat glass forming operation carried out as a substantially free-falling vertical stream. The glass may be received in a first chamber in a relatively deep and narrow reservoir, from which it flows to a wider chamber, from which, in turn, it is drawn longitudinally.

Vertical delivery arrangement for float glass process

A continuous ribbon of glass is reduced in thickness while supported on molten metal by imposing super-atmospheric pressure over a molten glass layer in a chamber where the glass is maintained in contact with the side walls of the chamber. One aspect features metering the glass layer into the pressure chamber at substantially full width. Another aspect involves pressure sizing the glass layer at temperatures above 2100.degree. F. (1150.degree. C.).

Pressure sizing of float glass

A float glass forming chamber with electrical heating means is provided with a plurality of compact housings to enclose electrical connections, thereby avoiding the conventional overhead plenum chamber. Also, a gas-tight casing directly overlying the roof elements serves to minimize the volume of the overhead structure. Both features reduce condensation and drippage of volatile materials within the chamber and improve access to forming chamber elements.

Float glass forming chamber having low profile roof

A float glass forming chamber is provided with a simplified roof structure comprised of suspended refractory slabs, whereby the number of joints and non-planar interior surfaces are reduced so as to suppress condensation and drippage of volatile materials within the chamber.

Float glass forming chamber with a flat slab roof

An edge engaging device for attenuating a ribbon of float glass having a single elongated barrel and a plurality of operatively interconnected edge rolls secured near one end thereof. The edge rolls are rotatable about a generally horizontal axis angularly related to the longitudinal center line of the elongated barrel, and means are provided to adjust the angular relationship thereof.

Apparatus and method for attenuating float glass

The invention comprises a temperature sensing device comprising a thermocouple which is protected by a woven cloth. The cloth is impervious to wetting or transmission of the molten material whose temperature is to be measured. A thermocouple further is surrounded by weights of greater density than the molten metal in order to hold the thermocouple below the surface of the molten metal.

Apparatus for measuring temperatures in molten metal

A plurality of high-temperature operating, corrosion-resistant heat pipes are employed to distribute heat transversely and longitudinally from normally hotter portions of a glass forming chamber to normally cooler portions of the same chamber in order to provide a more uniform thermal environment for the forming of flat glass. In particular, heat pipes are provided beneath the surface of a pool of glass-supporting molten metal in such a chamber to remove heat from a central and usually upstream region of such a chamber and transfer it to a marginal and preferably downstream region of the chamber. By transferring the heat in this manner, the temperature gradients within the chamber may be manipulated to be more uniform throughout a forming region so that glass of improved quality can be produced with improved efficiency, utilizing less energy than normally required for producing glass according to typical conventional float glass manufacturing methods.

Apparatus and method using heat pipes for manipulating temperature

An apparatus and method are provided for recovering waste heat from the exhaust of a combustion-heated glass melting furnace and transferred by heat pipes to an enclosure in which incoming glass batch materials are preheated prior to being fed to the furnace for melting. The batch materials are efficiently preheated with the waste heat without permitting direct contact between the exhaust effluent and the batch materials so that the entrainment and discharge of batch dust with the effluent is avoided.

Glassmaking furnace employing heat pipes for preheating glass batch

Flat glass is produced by advancing a layer of molten glass on the surface of molten metal while cooling it sufficiently to form a continuous sheet of glass which is lifted upwardly from the surface of the supporting pool of molten metal and conveyed upwardly from it for further processing. A method is provided for selectively controlling the temperature, and thus the viscosity, of the glass of selected portions across the width of the continuous sheet of glass in order to adjust and maintain the relative lengths of the respective portions of the continuous sheet of glass as it is lifted upwardly from the supporting pool of molten metal and to thereby control the flatness of the continuous sheet of glass as it is ascending from the supporting pool of molten metal.

Apparatus and method for controlling the flatness of a newly-formed

Movable lateral and longitudinal dam barriers are provided in a glass forming chamber of the type containing a molten metal. The movable lateral dam barriers control longitudinal convection currents in the molten metal to control the temperature of the glass as it moves through the forming chamber. The lateral dam barriers can be moved to change longitudinal convection currents to achieve the optimum temperature conditions in the glass ribbon for producing flat glass of a specific thickness at any desired ribbon speed. The lateral dam barrier can also be moved to change convection currents and glass ribbon temperature to facilitate the change over from producing a glass ribbon of one thickness to a glass ribbon of a different thickness. The movable longitudinal dam barriers control lateral convection currents in the molten metal to flatten the edge-to-edge temperature profile across the ribbon of a glass ribbon moving through the chamber supported on the molten metal.

Growing community of inventors

Arnold, PA, United States of America

John E Sensi