Title:
高清浄鋼の溶製方法
Document Type and Number:
Japanese Patent JP7035873
Kind Code:
B2
Abstract:
To provide a method of smelling steel into high cleaned steel capable of producing cast high cleaned steel by smelling in which deoxidation product is removed to be reduced rather than prior art.SOLUTION: When a vacuum degassing treatment is conducted by immersing an immersion pipe 12 of a vacuum degassing device 10 into a molten steel in a ladle 13 in which melting oxygen concentration is 40 ppm or less by adding metal Al to the molten steel which has been subjected to primary refining and blowing an inert gas, the inert gas is blown at 1.3 to 4.0 NL/min./ton under low pressure vacuum atmosphere of 1.3 kPa or less for 15 to 45 min. in first half, and the inert gas is blown at 0.3 to 1.1 NL/min./ton under high pressure vacuum atmosphere of 40 to 67 kPa for 5 to 15 min. in second half, then the vacuum degassing treated molten steel is poured into a tundish 15 in which a dam 20 partitioning a molten metal receiving section 17 and a metal discharging section 19 is arranged inside at a state upwardly projecting from a bottom, and height of the dam 20 is set at 0.3 to 0.8 times of molten steel depth.SELECTED DRAWING: Figure 1
Inventors:
Kenichiro Miyamoto
Taichi Nakae
Eiji Watanabe
Naoya Ohara
Taichi Nakae
Eiji Watanabe
Naoya Ohara
Application Number:
JP2018134998A
Publication Date:
March 15, 2022
Filing Date:
July 18, 2018
Export Citation:
Assignee:
Nippon Steel Corporation
International Classes:
C21C7/10; B22D1/00; B22D11/10; C21C7/00; C21C7/04
Domestic Patent References:
| JP2018066031A | ||||
| JP2017166026A | ||||
| JP9287017A | ||||
| JP2000038613A |
Attorney, Agent or Firm:
Nakamae Fujio
Yoshihiro Kurita
Yohei Kiyoi
Yoshihiro Kurita
Yohei Kiyoi