Nippon Steel Corporation

Ryohei Mizoguchi

Kazumi Nishimura

Hisao Odashima

Shigeto Fujii

Tetsuya Ohara

Hiroshi Mure

Kaoru Ichikawa

Shigeru Fujihara

Shinichi Yokoi

Process for manufacturing a galvanized steel sheet, comprising steps of coating a steel sheet with nickel in an amount of from 0.2 to 2 g/m.sup.2, heating the steel sheet thus coated to a temperature within the range of from 420.degree. C. to 500.degree. C. in a non-oxidative atmosphere, and dipping the nickel coated steel sheet into a molten zinc bath containing aluminum at a content of from 0.1 to 1% without contact with air, wherein the steel sheet is dipped into the molten zinc bath within 15 seconds after the temperature of the steel sheet exceeds 350.degree. C. in the heating step. An apparatus for performing the process comprises a nickel electroplating apparatus, a non-oxidative atmosphere-heating apparatus, and a galvanizing apparatus equipped with a molten zinc adhering amount-controlling device at the outlet side thereof, arranged sequentially in the steel sheet delivery direction, said non-oxidative atmosphere-heating apparatus comprising a ring transformer having a space for steel sheet delivery, a conductor roll provided at the inlet side of the ring transformer and being connected by use of an electroconductive member to a molten zinc bath of the galvanizing installation, thus a secondary coil of the transformer being formed from the conductor roll, the electroconductive member and the delivered steel sheet between the entering point in the molten zinc bath and the conductor roll contact point, and an atmospheric gas-feeding device for feeding a non-oxidative gas to the atmospheric chamber.

Process for manufacturing galvanized steel sheet by nickel pre-coating

Process for manufacturing a galvanized steel sheet, comprising steps of coating a steel sheet with nickel in an amount of from 0.2 to 2 g/m.sup.2, heating the steel sheet thus coated to a temperature within the range of from 420.degree. C. to 500.degree. C. in a non-oxidative atmosphere, and dipping the nickel coated steel sheet into a molten zinc bath containing aluminum at a content of from 0.1 to 1% without contract with air, wherein the steel sheet is dipped into the molten zinc bath within 15 seconds after the temperature of the steel sheet extends 350.degree. C. in the heating step. And apparatus for performing the process comprises a nickel electroplating apparatus, a non-oxidative atmosphere-heating apparatus, and a galvanizing apparatus equipped with a molten zinc adhering amount-controlling device at the outlet side, arranged sequentially in the steel sheet delivery direction, thereof said non-oxidative atmosphere-heating apparatus comprising a ring transformer having a space for steel sheet delivery, a conductor roll provided at the inlet side of the ring transformer and being connected by use of an electroconductive member to a molten zinc bath of the galvanizing installation, thus a secondary coil of the transformer being formed from the conductor roll, the electroconductive member and the delivered steel sheet between the entering point in the molten zinc bath and the conductor roll contact point, and an atmospheric gas-feeding device for feeding a non-oxidative as to the atmospheric chamber.

An anode system for plasma heating usable in the tundish of a continuous casting apparatus, which is economical and simple in structure and can enjoy a long service life, and comprises a dam member provided on the bottom surface of a tundish near and along a side wall or an over-flow wall of the tundish to form a space or gap therebetween, an electrical conductive member with its end portion exposed to the space or gap and the other end electrically connected to a power source, said dam member having a height higher than a level of molten metal remaining after the pouring of the molten metal from the tundish, but lower than a minimum level of molten metal normally contained in the tundish.

Anode system for plasma heating usable in a tundish

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Hyogo, Japan

Ryohei Mizoguchi