Method and casting mold for manufacturing a quartz glass body

US8104309B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

• Manfred Borens · Mainz, DE
• Franz-Peter Eckes · Bubenheim, DE
• Janus Zborowski · Ingelheim am Rhein, DE
• Karsten V. Westernhagen · Mainz, DE
• Stefano Merolla · Mainz, DE
• Joerg Witte · Darmstadt, DE
• Joachim Kuester · Langen (Hessen), DE
• Marcus Holla · Biebelnheim, DE

Key dates

• Filing date: Dec 20, 2007
• Grant date: Jan 31, 2012
• Expiry date: May 24, 2028

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P70/50
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The method provides an improved quartz glass body, especially an improved quartz glass crucible for melting non-metals, non-ferrous metals, or silicon. The quartz glass body is made by a method in which a quartz glass-water mixture is supplied to a gypsum casting mold comprising an outer part and an inner part, dried in the gypsum mold, and put under an overpressure via a system of ducts in the form of textile tubes embedded in the mold during the drying. Later a resulting green glass body is removed from the mold. At least a portion of the shaping surfaces of the inner part of the gypsum mold are surfaces of a water-impermeable substance. The method provides a cast body with a reduced tendency to crack and with a smaller open porosity.