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:
Oct. 22, 1991
Filed:
Mar. 06, 1991
Applicant:
Inventors:
Ronald N Molenaar, Heemskerk, NL;
Rienk M Nijholt, Noord-Scharwoude, NL;
Assignee:
Hoogovens Groep BV, Ijmuiden, NL;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21B / ;
U.S. Cl.
CPC ...
266 45 ; 75467 ; 75584 ; 266271 ;
Abstract
In the manufacture of pig-iron in a shaft furnace, a taphole is closed with hardened plugging compound during making of the iron and is opened for the tapping of the iron and then resealed. The resealing of the taphole comprises inserting hardenable plugging compound into the taphole and, before hardening thereof, driving a hollow tube into the plugging compound. The hollow tube has an open front end. The tube is pulled out at the next tapping. The use of a tube avoids disturbance of the plugging compound and creates a smoother taphole, leading to improved flow of liquid iron.