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:
Feb. 28, 1978
Filed:
Nov. 04, 1976
Applicant:
Inventor:
Rolf Groger, Oberhausen, DT;
Assignee:
August Thyssen-Hutte AG, Duisburg-Hamborn, DT;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21B / ;
U.S. Cl.
CPC ...
266 44 ; 264 30 ; 264 32 ; 266280 ; 266285 ;
Abstract
In the operation of a furnace for the production of iron or steel, the air preheater and the pipe communicating the preheater with the furnace are constructed of steel shells lined with an acid-resisting cement, with refractory lining overlying the cement. The acid-resisting cement is composed of quartz sand and refractory material in the form of hollow spheres, silicate binder, and hardener. The spheres are 10 - 40 vol.% of the total volume of quartz sand and spheres.