Title:
STEEL MANUFACTURING METHOD
Document Type and Number:
WIPO Patent Application WO/2020/004501
Kind Code:
A1
Abstract:
The steel manufacturing method includes: a process in which molten steel is tapped into a ladle from a steel-melting furnace; and a process in which the molten steel tapped into the ladle is discharged from the ladle and forged. When receiving the molten steel tapped from the steel-melting furnace into the ladle, an auxiliary material, which is made of an oxide in an amount W resulting in a slag thickness T of 0.02 m or thicker as calculated using the following formula (1), is placed on the bottom part of the ladle before starting to receive the molting steel, or the molten steel tapped from the steel-melting furnace is received into the ladle while adding the auxiliary material at the start of the reception of the steel. Preferably, the composition of the auxiliary material satisfies CaO/Al2O3: 0.8-4.0, 5% ≤ SiO2 ≤ 10%, and MgO ≤ 10%.
(1): T = (W/ρ)/((π⋅D2)/4)
In the formula, D: ladle diameter (m), ρ: molten oxide density (= 3,000 kg/m3), and W: amount of auxiliary material (kg).
Inventors:
OKAYAMA ATSUSHI (JP)
Application Number:
PCT/JP2019/025471
Publication Date:
January 02, 2020
Filing Date:
June 26, 2019
Export Citation:
Assignee:
NIPPON STEEL CORP (JP)
International Classes:
C21C7/00; C21C5/46; C21C7/076
Foreign References:
| JP2013159811A | 2013-08-19 | |||
| JPH1192811A | 1999-04-06 | |||
| JPH0718322A | 1995-01-20 | |||
| JP2012082513A | 2012-04-26 | |||
| JPH0860229A | 1996-03-05 | |||
| JPS6092417A | 1985-05-24 | |||
| JPS5613426A | 1981-02-09 | |||
| JP2003293022A | 2003-10-15 | |||
| JP2001107130A | 2001-04-17 |
Attorney, Agent or Firm:
TAIYO, NAKAJIMA & KATO (JP)
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