Kawasaki Steel Corporation

Jfe Steel Corporation

Yasuo Kishimoto

Naoki Kikuchi

Katsunori Takahashi

Takashi Yamauchi

Toshikazu Sakuraya

Shuji Takeuchi

Hiroshi Nishikawa

Koji Yamaguchi

Yuji Miki

Masato Kumagai

Hisahiro Matsunaga

Masaru Washio

Kazuhisa Hamagami

Hiroyuki Tobo

Nagayasu Bessho

Seiji Nabeshima

Fumio Sudo

Akitoshi Matsui

Yoshie Nakai

Futoshi Ogasawara

Tomomichi Terabatake

Hiromitu Shibata

Shunichi Kawanami

Kimiharu Aida

Yasuyoshi Takao

Maki Iwasa

Takehito Matsuda

Provided are a scrap determination system and method that can improve scrap determination techniques. A scrap determination system () comprises: a first scrap determination model () generated using teaching data including first learning images, and determines, based on a camera image, grade of scrap in the image and a ratio of the grade; a second scrap determination model () generated using teaching data including second learning images, and determines, based on the image, grade of scrap in the image and a ratio of the grade; a selection model () configured to determine which of the first scrap determination model () and the second scrap determination model () is to be used, based on the image; and an output section () configured to output information of each grade of scrap and a ratio of the grade determined based on the image using the model selected by the selection model ().

Scrap determination system and scrap determination method

A steel continuous casting method using a continuous caster that includes a pair of upper magnetic poles and a pair of lower magnetic poles is disclosed. The method comprises braking a molten steel flow with DC magnetic fields respectively applied to a pair of upper magnetic poles and a pair of lower magnetic poles while stirring the molten steel with an AC magnetic field simultaneously applied to the pair of upper magnetic poles, the strength of an AC magnetic field applied to the upper magnetic poles and strengths of DC magnetic fields applied to the upper magnetic poles and the lower magnetic poles are controlled within a particular ranges in accordance with the width of a slab to be cast.

Steel continuous casting method

A steel continuous casting method using a continuous caster that includes a pair of upper magnetic poles and a pair of lower magnetic poles is disclosed. The method comprises braking a molten steel flow with the DC magnetic fields respectively applied to the pair of upper magnetic poles and the pair of lower magnetic poles while stirring a molten steel with an AC magnetic field simultaneously applied to the pair of upper magnetic poles, the strength of an AC magnetic field applied to the upper magnetic poles is set within the range of 0.060 to 0.090 T and the strengths of DC magnetic fields applied to the upper and lower magnetic poles are controlled within particular ranges in accordance with the width of the slab to be cast and the casting speed.

The composition of inclusions and the S concentration in steel are controlled in a manner such that, among the CaO-containing oxide inclusions present in a Ca-containing steel, an equilibrium S soluble amount (% S inc.) of at least 80% of the oxide inclusion particles having a particle diameter of 2 &#x3bc;m or more are about 0.03 wt % or less, thereby inhibiting rust formation due to the inclusions, thus solving a problem which has long been of concern in Ca-containing steels.

Rust-resistant calcium steel

Production method for continuous casting cast billet

A method of rapidly reducing chromium oxide-containing slag and the like in large quantities, in a simplified manner and without requiring high temperatures. Chromium oxides are reduced with at least one of elementary sulfur and compounds of sulfur having a valence less than 6. For an aqueous solution of the sulfur component, desirably, its sulfur content is more than 0.03% by weight. As the sulfur source, preferred is blast furnace slag (e.g., non-aged, gradually-cooled blast furnace slag) that is discharged in large quantities in the iron industry. Cr in chromium oxides is reduced in one of the following ways: (a) Chromium oxide-containing substances are sprayed with or immersed in blast furnace slag-released water that has been used in cooling blast furnace slag. (b) Chromium oxide-containing substances are mixed with blast furnace slag, and then kept in an air atmosphere. Optionally, the mixture is sprayed with blast furnace slag-released water. (c) Chromium oxide-containing substances are mixed with blast furnace slag, and then steamed. (d) Prior to the reduction treatment, chromium oxide-containing substances are preferably steamed. 100 parts by weight of reduced chromium oxide-containing compounds are mixed with from 0.1 to 90 parts by weight of sulfur-containing slag, and used in various civil engineering works.

Method for processing chromium oxide-containing substances in large quantities, method for utilizing the processed substances, and products comprising the processed substances

Process for smelting reduction of chromium ore

A method of producing an ultra-low-carbon steel by conducting vacuum-decarburization of a molten steel by means of a vacuum degasifier of the type having recirculation pipes and a vacuum chamber. When the carbon content of the molten steel has come down to a level of 50 ppm or less, hydrogen gas is introduced together with an inert gas into the molten steel either by directly injecting a hydrogen-containing gas into the molten steel in the vacuum chamber through a tuyere provided in the wall of the vacuum chamber or by blowing the hydrogen-containing gas onto the surface of the molten steel in the vacuum chamber through a lance provided in the vacuum chamber. In order to enhance the effect produced by the method of the present invention, it is possible to take an additional measure such as blowing of hydrogen gas through a tuyere provided in the wall of the recirculation pipe or injection of hydrogen or hydrogen-containing gas through an injection lance immersed in the molten steel held in, a ladle.

Method of producing ultra-low-carbon steel

A method of producing an ultra-low-carbon steel by using a vacuum degasser on a molten steel has the steps of conducting vacuum decarburization to attain a predetermined level of carbon content, e.g., 25 ppm or below, in the molten steel while progressively reducing the pressure in said vacuum degasser, conducting addition of hydrogen in which hydrogen is dissolved in said molten steel while said pressure is temporarily elevated to 20 Torr or above, and conducting final decarburization after reducing said pressure to 2 Torr or below. The addition of hydrogen may be conducted to meet the following conditions:

Growing community of inventors

Chiba, Japan

Yasuo Kishimoto