Quasi-containerless glass formation method and apparatus

US4654065A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• Robert J. Naumann · Huntsville, US
• Edwin C. Ethridge · Huntsville, US

Key dates

• Filing date: Dec 5, 1985
• Grant date: Mar 31, 1987
• Expiry date: Dec 5, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03B2205/04
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Apparatus and method for forming ultrapure glass rods (13) or fibers (28) from a polycrystalline rod (11) in which the method comprises the steps of heating a selected short section of the rod in the first furnace (21) to form a molten zone of the rod, heating a second selected short section of the rod in a second furnace (19) which initially is separated from the first furnace by a very short gap to form a second molten zone of the rod which initially is contiguous with and part of the first molten zone of the rod to form a single molten zone 14, and then gradually moving the first and second furnaces apart to first form a rod (13) and then, ultimately, a fiber (28), of ultrapure glass in the increasingly widening gap forming therebetween.