Kawasaki Steel Corporation

Otto LLC

Kawasaki Seitetsu Kabushiki Kaisha

Tsuguhiko Nakagawa

Susumu Okada

Masahiko Morita

Kouichi Hirata

Susumu Sato

Susumu Satoh

Koushi Kuramoto

Yoshio Abe

Kazuhiro Kojima

Kusuo Furukawa

Takao Ogawa

Kenta Karube

Takemi Yamamoto

Hiroshi Okamoto

Satoshi Shibuya

Toshikazu Kaihara

Yoshiharu Fujiwara

Koshi Kuramoto

Masaharu Yoshida

Mamoru Yagi

Toshiyasu Yuri

Masamitsu Obashi

Nobuaki Hanazono

Motohiro Hirata

Yoshiyuki Nakanishi

Jun Morozumi

Shoshichiro Tajima

Junichi Hasunuma

Hisashi Osanai

Ryosuke Yamaguchi

Sakae Mochizuki

Toshiyuki Iwatani

A method for cooling the heating furnace during the dormant stage of the heating furnace; said method surely and sufficiently shortens the cooling time of the heating furnace irrespective of seasons such as summer or winter, and yet, without damaging the inner furnace refractories. Furthermore, the method is applicable to ceramic fiber furnaces. The method comprises: inserting, from an extracting port to the inside of the heating furnace, a plurality of lances being arranged along the width direction of the extracting port of said furnace while taking a predetermined distance between each other; and spraying, from a plurality of spray nozzles provided on the lances, a coolant in the form of a mist against a scale deposited inside the heating furnace. Optionally, a cooling fan is provided to forcibly supply a cooling air into the heating furnace.

Method and apparatus for cooling furnace

This invention aims at providing a method of continuously carburizing a metal strip, which is capable of providing industrially optimum carburization conditions while attaining non-soot-generating atmospheric data, desired carburization concentration distribution and desired carburization rate, in a case where a strip passed through a carburization furnace is carburized continuously in a surface reaction rate-governing area in which the carbon concentration in a superficial layer of the strip has not yet reached an equilibruim level with respect to the time. The method consist of carburization concentration distribution (S7), on the basis of the carburization conditions including given specification data for the steel plate, furnace temperature and composition of the atmospheric gas, outputting the concentration of the components of the atmospheric gas, feed and discharge rates and other carburization conditions when the set carburization rate and an actual carburization rate are equal (S8-S15), and correcting the set carburization rate when a difference between the set carburization rate and an actual carburization rate is large, and correcting the strip feed rate while correcting the composition of the atmospheric gas when a difference between the predetermined carburization rate and set carburization rate is large (S9).

Method of continuously carburizing metal strip

A continuous heat treating furnace in which heat is efficiently recovered from the combustion exhaust gas from the heating section of a continuous annealing furnace. The continuous annealing furnace of the metal strip is a heating furnace or a heating device provided with plural burners for heating to a predetermined temperature a steel material or a continuously supplied metal strip by means of combustion of the burners; a regenerative heat exchanger for collecting a sensible heat of a combustion exhaust gas of the burners, reserving the heat in a regenerator and supplying a predetermined gas to the regenerator to recover the heat to the predetermined gas; and a preheating section for blowing the predetermined gas from the regenerative heat exchanger to the metal strip for preheating. The heat exchanger body is divided into at least three sections, each section having a regenerator. When the heat exchanger body is continuously or intermittently rotated, each section is provided with a path for successively repeating to pass a heating section combustion exhaust gas for applying a sensible heat of exhaust gas to the regenerator, a purging gas for removing debris sticking to the regenerator when applying the sensible heat of the heating section exhaust gas and a circulating gas for collecting the sensible heat of the regenerator and blowing the heat to the metal strip passing the preheating section to raise a temperature of the metal strip.

Heat treating furnace for a continously supplied metal strip

Heating method and apparatus

Non-oxidizing heating method and apparatus

Heating apparatus including plurality of regenerative burner units and

A high tensile steel sheet excelling in workability and stretch flanging formability, which is of a composite texture composed of a ferrite phase and a 2nd phase selected from the group consisting of martensite, bainite, pearlite, retained austenite and cold-transformed ferrite, wherein the volume fraction of the 2nd phase is hoe less than about 1.3 times higher at an outer region of the steel sheet than the volume fraction of the 2nd phase in a central region of the sheet thickness.

Method of producing a high tensile steel sheet having excellent stretch

The present invention provides a steel sheet for press working that exhibits excellent stiffness and satisfactory press workability. The steel sheet for press working includes: a composition of C+N+B=0.007 to 1.0 wt % in a region from the surface of the steel sheet to a position of 5% of the thickness in a direction of the thickness in at least either of the surface layers; a pole intensity of [{321}+{211}]/{100}.gtoreq.1.2 in a vertical direction to the sheet surface realized at a 3% thickness position in the direction of the thickness from the surface; and a composition of C+N+B=0.010 wt % less than in the central portion 40% except for two 30% portions of the two surface layers in the direction of the thickness.

Steel sheet for press working that exhibits excellent stiffness and

A high tensile steel sheet excelling in workability and stretch flanging formability, which is of a composite texture composed of a ferrite phase and a 2nd phase selected from the group consisting of martensite, bainite, pearlite, retained austenite and cold-transformed ferrite, wherein the volume fraction of the 2nd phase is not less than about 1.3 times higher at an outer region of the steel sheet than the volume fraction of the 2nd phase in a central region of the sheet thickness.

High tensile steel sheet having excellent stretch flanging formability

A continuous annealing line for annealing a cold-rolled strip of a ultra-low-carbon steel comprising a heating furnace for heating the strip which is fed continuously, with or without a soaking furnace following the heating furnace, a cooling furnace in which the heated steel strip is cooled, and a carburizing/nitriding furnace disposed between the heating furnace or the soaking furnace and the cooling furnace. The carburizing/nitriding furnace may be divided into a plurality of zones, each of which is provided with control means for controlling the carburizing/nitriding atmosphere and carburizing/nitriding temperature in the zone. The continuous annealing line may further comprise a plurality of carburizing/nitriding furnaces and have an arrangement for conducting a switching between a mode in which the carburizing/nitriding furnace is used for carburizing/nitriding the steel strip and a mode in which the carburizing/cooling furnace is used for cooling the steel strip.

Continuous annealing line having carburizing/nitriding furnace

Growing community of inventors

Kurashiki, Japan

Tsuguhiko Nakagawa