Kawasaki Steel Corporation

Toshio Fujimura

Toshitane Matsukawa

Shinji Kojima

Arata Ueda

Tetsuya Fujii

Yukio Oguchi

Toshihiko Emi

Hisakazu Mizota

Yoshio Yoshimoto

Norio Sumida

Osamu Furukimi

Saiji Matsuoka

Masahiko Morita

Takemi Yamamoto

Takuo Imai

Kenichi Orito

Noriaki Inoue

Takashi Sekita

Susumu Yuhara

Taro Yahiro

Kunihiro Ito

Kouichi Kushida

Steel having excellent workability and deep drawability is produced by an electric furnace-vacuum degassing process. The steel has a composition which comprises about:

Steel, steel sheet having excellent workability and method of producing

Continuous forging apparatus for cast strand

A method of continuous compression forging, with a compression forging anvil, the final solidified region of cast steel drawn out from a mold for continuously casting, comprising the step of: compressing said cast steel with said anvil at a compressing cycle which meets the following conditions: ##EQU1## where t: the compressing cycle (sec), .delta.: the overall thickness reduction, Vc: the casting speed (mm), D: the cast steel thickness before compression forging, .theta.: the inclination angle (.degree.) with respect to the flat surface of the anvil. An apparatus for continuous compression forging continuously cast steel comprising: at least a pair of anvils for vertically holding the pass line of cast steel drawn out from a mold for continuous casting and continuously compression-forging the final solidified region of the moving cast steel by moving the anvils toward and away from each other; a frame; a slider; and links, wherein either of said anvils is disposed within said frame which has a port through which said cast steel is introduced, another anvil is secured to said slider which can be reciprocated along a sliding surface formed in said frame, and said frame and said slider are hung from a crank shaft via said links, said crank shaft acting to move said anvils toward and away from each other.

Method and apparatus for continuous compression forging of continuously

A segregation preventive or eliminative operation in a continuous casting process is performed under the following conditions:

A method of stirring molten metal by repeatedly sucking and rapidly discharging part of the molten metal into and out of a refractory cylinder having a lower opening end immersed in the molten metal in a ladle, comprises operating the stirring under a condition that an inner diameter (d) of the refractory cylinder is less than 1,000 mm, a relation between the inner diameter (d, mm) of the refractory cylinder and weight (W, ton) of the molten metal in the ladle is d/W.sup.0.5 &gt;30, and an immersed depth of the refractory cylinder is within 200-700 mm. A pressurized gas for discharging the sucked molten metal out of the cylinder is introduced thereinto in an inclined direction relative to a vertical line against a point on an opposite inner wall of the cylinder at least 500 mm above the maximum suction level of the molten metal in the cylinder. A refractory cylinder operated in the above manner according to the invention comprises a flange connection between an uppermost and an intermediate cylinder parts of the cylinder at a location higher than the maximum suction height of the molten metal and a further flange connection between the intermediate cylinder part and a lowermost cylinder part. The refractory cylinder comprises at its immersed end a flow restricting opening to obtain more strong stirring the molten metal.

Method of stirring molten metal and refractory cylinder for the purpose

A method of refining molten metal with stirring in a refining vessel by repeated operation of suction and discharge is disclosed, wherein a lower end of a refractory cylinder is immersed into a molten metal bath in the vessel and an inside of the cylinder opposite to the immersed end is alternately subjected to evacuation and pressurization. In this method, maximum and average values of pressure reduction velocity to be applied to the inside of the cylinder are limited to not more than 1,000 mmHg/sec and not more than 500 mmHg/sec, respectively, and an evacuation time is extended over at least 1.5 times intrinsic oscillation period of up and down movement of molten metal column inside the cylinder.

Method of refining molten metal with stirring by repeated operation of

Growing community of inventors

Okayama, Japan

Toshio Fujimura