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, 2002
Filed:
Nov. 14, 2000
Kenichiro Miyamoto, Kitakyushu, JP;
Katsuhiko Kato, Kitakyushu, JP;
Akio Shinkai, Kitakyushu, JP;
Takayuki Kaneyasu, Kitakyushu, JP;
Shinya Kitamura, Futtsu, JP;
Hiroyuki Ishimatsu, Kitakyushu, JP;
Hiroshi Sugano, Kitakyushu, JP;
Keiichi Katahira, Futtsu, JP;
Ryuzou Hayakawa, Kitakyushu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
In a straight barrel type vacuum refining apparatus, use is made of a combination of: a decarburization method wherein the flow rate of oxygen fed into a vacuum tank and the flow rate of an inert gas fed into the vacuum tank are regulated and, at the same time, the flow rate of oxygen gas blown is reduced at a rate of 0.5 to 12.5 Nm /h/t/min in a low carbon concentration region having a carbon concentration of not more than the critical carbon concentration; and a vacuum refining apparatus provided with dust accumulation preventing means.