To obtain a hot dip plated steel sheet excellent in plating adhesion by subjecting a hot rolled steel sheet to descaling pickling treatment, thereafter spraying ice particles thereto, executing desmutting and thereafter introducing it into a continuous plating stage.
A hot rolled steel sheet 12 supplied from a coil 11 is subjected to descaling pickling treatment by a descaling pickling device 13, thereafter the hot rolled steel sheet 12 after the treatment is sprayed with ice particles from an ice particle spraying device 14, and desmutting is executed. Successively, hot dip plating treatment is executed by a continuous hot dip plating device 15. Or, the hot rolled steel sheet 12 is sprayed with ice grains and is directly subjected to descaling pickling treatment by pickling in which the temp. is held to the range of 80 to 90°C by a heater 18 in a descaling pickling device 13'. The hot rolled steel sheet 12 after this treatment is again sprayed with ice particles, is subjected desmutting and is thereafter applied with hot dip plating. Or, the hot rolled steel sheet 12 heated at ≥300°C is sprayed with ice particles to reduce the surface temp. of the steel sheet to the proper one, and after that, it is subjected to descaling pickling treatment and is successively subjected to hot dip plating treatment.
NOMURA SHUJI
INAGAKI JUNICHI
SAGIYAMA MASARU
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