Method for producing a cylinder of quartz glass using a holding device and appropriate holding device for performing the method

US8484997B2 · kind B2 · utility

Assignee

• HERAEUS QUARZGLAS GMBH & CO. KG · DE

Inventors

• Frank Hoff · Bitterfeld-Wolfen, DE
• Michael Muschler · Roßlau, DE
• Udo Peper · Bodenwerder, DE
• Sven Schmidt · Landsberg, DE
• Steffen Zwarg · Wolfen, DE
• Hans-Georg Fritsche · Bitterfeld-Wolfen, DE

Key dates

• Filing date: Jun 5, 2008
• Grant date: Jul 16, 2013
• Expiry date: Mar 11, 2030

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P40/57
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A known method for producing a cylinder of quartz glass comprises a method step in which a porous SiO2 body comprising a central inner bore, a lower end and an upper end is sintered in a sintering furnace zone by zone, starting from the upper end, to obtain the quartz glass cylinder, a holding device being used by means of which the SiO2 body is held standing in vertical orientation during a first sintering phase and suspended in a second sintering phase. Starting therefrom, to indicate a method by means of which even heavy bodies of porous SiO2 can be reliably held during sintering, it is suggested according to the invention that the holding device comprises a fusion body of quartz glass which is arranged in the area of the upper end in the inner bore and which in the course of the first sintering phase fuses with the quartz glass of the SiO2 body and which during the second sintering phase is in operative interaction with a holding element of the holding device and together with said element contributes to a suspended holding of the SiO2 body to be sintered.