The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 2019
Filed:
Jun. 29, 2016
Heraeus Quarzglas Gmbh & Co. KG, Hanau, DE;
Oliver Ganz, Bruchkoebel, DE;
Harald Hain, Kahl, DE;
Heraeus Quarzglas GmbH & Co. KG, Hanau, DE;
Abstract
A method for producing substrate tubes of quartz glass includes continuously supplying a hollow cylinder of quartz glass to a heating zone, softening the hollow cylinder zonewise in the heating zone, and drawing off a tubular strand from the softened portion. The hollow cylinder has an outer diameter C, an inner diameter Cand an inner bore. The tubular strand has an outer diameter Tand an inner diameter T. The following parameters are applicable to the hollow cylinder and the tubular strand: C>180 mm, C>3 with C=C/C, T<1.6 with T=T/Tand C/T<2.5. The blow pressure in an inner bore is adjusted to a value in the range of 4 to 10 mbar. Substrate tubes, obtained by cutting the tubular strand to the desired length, serve as semi-finished products for the manufacture of preforms for optical fibers.