US 6,629,437 B1 · Method of improving the quality of glass

Abstract

The invention relates to a method for suppressing the formation of oxygen gas bubbles at the contact interface between a glass melt and a component of a glass melting arrangement with this component being made of a precious metal. This component is especially the precious metal lining of a feed channel. The characterization “precious metal” includes in this context: platinum, gold, rhenium, all other metals of the platinum group, the alloys of the above-mentioned metals and the above-mentioned metals and alloys in dispersion oxide enhanced form. The occurrence of gas bubbles at the phase boundary between precious metal and the glass melt has been known for some time without effective measures having been suggested up until now to improve significantly the quality and yield of the generated glass products, particularly because precious metal parts have to be arranged in the glass manufacture downstream of the usual purification devices with which gas bubbles can be removed from the melt. To solve the task resulting therefrom, it is provided in accordance with the invention that the part, which is made of precious metal, is electrically conductively connected to one or several electrodes which are arranged spaced from the part, which is made of precious metal, in the glass melt, and that a potential drop is generated between the electrode and the part made of precious metal so that a current flows.

Claims26

Dependent claims

A method for suppressing the formation of oxygen gas bubbles at the contact interface between a glass melt and a component of a glass melting arrangement, the component of the glass melting arrangement being made of a precious metal, the method comprising the steps of:

providing at least one electrode and mounting said electrode in said melt in spaced relationship to said component;
electrically connecting said component to said electrode;
and,
generating a potential drop between said electrode and said component to cause a current to flow and maintaining an electrical negative potential difference referred to the glass melt at said component made of precious metal.

1 more element

providing at least one electrode and mounting said electrode in said melt in spaced relationship to said component;
electrically connecting said component to said electrode;
and,
generating a potential drop between said electrode and said component to cause a current to flow;
said precious metal is selected from the group consisting of platinum, gold, rhenium, the other metals of the platinum group, the alloys of the above-mentioned metals as well as dispersion oxide enhanced variations of the above-mentioned metals or their alloys are used;
said electrode is arranged in a region of the glass melt wherein the oxygen bubbles can be removed from the melt;
said electrode is mounted in the purification chamber of the glass melt arrangement;
said potential drop is generated in that one or several electrodes are used which carry negatively charged O2− ions from the glass melt;
and,
said electrodes comprise a tube of yttrium, calcium or magnesium stabilized zirconium oxide which is permeable for oxygen ions, the tube being closed at its end, a precious metal wire being electrically conductive connected to the inner wall of the tube and the other end being electrically conductive connected to the part of the glass melt arrangement made of precious metal.

7 more elements

Dependencies are inferred from the claim text.

Method of improving the quality of glass

Life of this patent

Method of improving the quality of glass

Life of this patent

Abstract

Claims26