EP0480122A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Process for manufacturing galvanized steel sheet by nickel pre-coating method
Assignee: Nippon Steel Corp
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Filing: 1991-05-15
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Granted: —
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Expires: 2011-05-15
Abstract
Abstract 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/m², heating the steel sheet thus coated to a temperature within the range of from 420°C to 500°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°C in the heating step, and apparatus for performing the process. The galvanized steel sheet has superior surface appearance and coating adherence.
Inventors
- 👤 Kazumi C/O Nippon Steel Corporation Nishimura
- 👤 Hisao C/O Nippon Steel Corporation Odashima
- 👤 Tetsuya C/O Nippon Steel Corporation Ohara
- 👤 Ryohei C/O Nippon Steel Corporation Mizoguchi
- 👤 Shigeto C/O Nippon Steel Corporation Fujii
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 06:01
CPC Classifications
C; C23; C23C; C23C2/00; C23C2/003; C23C2/0034; C23C2/00342; C23C2/00344; C23C2/0035; C23C2/0038; C23C2/004; C23C2/02; C23C2/022; C23C2/024; C23C2/026
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
100 words
A 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/m², heating the steel sheet thus coated to a temperature within the range of from 420°C to 500°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°C in the heating step.
Claim 2
Dependent Claim
83 words
A 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/m², heating rapidly the steel sheet thus coated at a heating rate of at least 30°C/s to a temperature within the range of from 430°C to 500°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.
Claim 3
Dependent Claim
196 words
A continuous hot-dip galvanization installation for galvanization of a nickel pre-coated steel sheet: comprising a nickel electroplating apparatus, a non-oxidative atmosphere-heating apparatus, and a galvanizing apparatus equipped with molten zinc adhering amount-controlling device at the outlet side, 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, where the resistance R₁ of the steel sheet and the resistance R₂ of the electroconductive member is in the relation of R₁ » R₂; an atmospheric chamber enclosing the steel sheet within the range from the inlet side or the backside of the conductor roll to the point just below the surface of the molten zinc bath; an atmospheric gas-feeding device for feeding a non-oxidative gas to the atmospheric chamber.
Claim 4
Dependent Claim
20 words
Galvanized steel sheet, producible with the process according to claims 1 and 2 or the installation according to claim 3.
References Cited (Backward Citations)
No citation records indexed.
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