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:
Aug. 18, 2020
Filed:
Feb. 15, 2017
Jfe Steel Corporation, Tokyo, JP;
Yusuke Fujii, Tokyo, JP;
Yoshie Nakai, Tokyo, JP;
Naoki Kikuchi, Tokyo, JP;
Naoya Shibuta, Tokyo, JP;
Shinichi Nagai, Tokyo, JP;
Takahiko Maeda, Tokyo, JP;
Yuji Miki, Tokyo, JP;
JFE STEEL CORPORATION, Tokyo, JP;
Abstract
A molten steel refining method includes throwing a powder to molten steel while heating the powder with a flame formed by combustion of a hydrocarbon gas at the leading end of a top blowing lance. The lance height of the top blowing lance (the distance between the static bath surface of the molten steel and the leading end of the lance) is controlled to 1.0 to 7.0 m, and the dynamic pressure P of a jet flow ejected from the top blowing lance calculated from equation (1) below is controlled to 20.0 kPa or more and 100.0 kPa or less. P=ρ× U/2 . . . (1) wherein P is the dynamic pressure (kPa) of the jet flow at an exit of the top blowing lance, ρthe density (kg/Nm) of the jet flow, and U the velocity (m/sec) of the jet flow at the exit of the top blowing lance.