Kawasaki Steel Corporation

Sumio Yamada

Fumio Sudo

Chikashi Tada

Seiji Itoyama

Hajime Bada

Keizo Taoka

Yuji Miki

Tetsuya Fujii

Nagayasu Bessho

Kenichi Sorimachi

Nozomu Tamura

Toshikazu Sakuraya

Yoshiei Kato

Saburo Moriwaki

Toshihiko Emi

Masaru Washio

Hiroshi Nomura

Hidenari Kitaoka

Hitoshi Morishita

Katsunori Takahashi

Toshio Kanatani

Osamu Haida

Hiraku Sonoda

Kanji Emoto

Shinichi Kaneko

Takahiro Mitumune

Masafumi Maeda

Eizo Maeda

Hajime Suzuki

Taichi Nakazawa

Yasuo Imaiida

Method of continuously casting austenitic stainless steel

Ladles used for vacuum refining processes, for example a VOD process, are provided with covers to cover openings of ladles. The covers generally consist of refractories, which are required to have excellent resistance to thermal spalling due to heat cycles and not inhibit decarbonization during refining processes of molten steel. The ladle cover comprises a refractory having a carbon content 5 wt % or more. Preferably, a refractory has a carbon content 5 wt % or more is used for a central section of the ladle cover, and a refractory having a carbon content less than 5 wt % is used for peripheral sections of the ladle cover.

Ladle cover for vacuum refining process

A method of controlling slag coating in a steel converter in which slag is left in the converter after tapping, and a slag solidifying agent is added to the slag to form a coated slag which is used to coat the bottom and/or side wall surface of the converter. The method is performed by

Method of controlling slag coating of a steel converter

A mold powder for use in continuous casting, containing specified amounts of CaO, Al.sub.2 O.sub.3, TiO.sub.2, Li.sub.2 O, BaO, MgO, F and Na.sub.2 O, and further containing at least one of BN and C as aggregate. The mold powder, when used in continuous casting of a steel rich in strong reducing metal elements such as Al, Ti, REM and so forth, remarkably suppresses generation of deterioration in the surface quality of the slab and break out of the slab which are attributable inferior lubrication.

Mold powder for continuous casting

Reduction of chromium oxide is performed by utilizing refinement or reduction container having top-blowing capability. Chromium oxide is charged in the molten iron bath in the aforementioned container. Content of slag is adjusted to maintain the following condition:

Method for producing chromium containing molten iron with low sulphur

A process of production of chromium containing molten iron generally comprises two steps. In a first step, top and bottom-blown reduction for reducing chromium is performed with charging carbon containing material and slag forming agent from the top of a converter for melting stainless scrap and for rising temperature of molten iron bath. In a second step which is performed subsequently to the first step, top and bottom-blown injection with charging chromium oxide and carbon from the top of the converter for reduction of chromium.

Process for producing chromium containing molten iron

A process for producing a steel in at least two converters using a great or substantial amount of an iron-bearing cold material. The iron-bearing cold material and a carbonaceous material are supplied into one of the converters under the presence of a molten iron or a preliminarily treated molten iron and are melted therein under oxygen-blowing to obtain a preliminarily treated molten iron containing a high content of carbon, and the preliminarily treated molten iron is refined in the other converter under oxygen-blowing to obtain a molten steel having the given composition.

Process of making steel in converter using a great amount of

Injection-desulfurization of a molten iron is carried out in a low cost by using powdery CaCO.sub.3 obtained by pulverizing limestone as a desulfurizing agent. This injection-desulfurization also can be attained by using a powdery mixture in which a main ingredient is said powdery calcium carbonate and not more than 30% by weight of powdery quicklime is added thereto, a powdery mixture in which a main ingredient is said powdery calcium carbonate and 5.about.20% by weight of a carbonaceous material and 2.about.15% by weight of at least one of halides of alkali and alkaline earth metals are added thereto, or a powdery mixture in which a main ingredient is said calcium carbonate and 5.about.20% by weight of a carbonaceous material, 2.about.15% by weight of at least one of halides of alkali and alkaline earth metals and not more than 30% by weight of powdery quicklime are added thereto, as the desulfurizing agent.

Method for desulfurizing a molten iron by injection

A desulfurizing agent for injection mainly consisting of lime powders having a particle diameter which allows at least 50 wt. % of the lime powders to pass through a screen mesh of 100 .mu.m and containing 0.015 to 1.0 wt. % of silicone oil surfactant, 10 to 40 wt. % of carbonate or hydroxide of alkaline earth metal, and 2 to 20 wt. % of carbon. The desulfurizing agent further contains 2 to 10 wt. % of at least one fluoride selected from the group consisting of fluoride of alkaline metal, fluoride of alkaline earth metal, cryolite, and sodium silicofluoride.

Desulfurizing agent for injection

Growing community of inventors

Chiba, Japan

Sumio Yamada