To provide a cold rolling method where the responsibility of lubricating oil feed control and the maintainability of emulsion whose diameter is made large are excellent, and insufficiency in lubrication can efficiently be prevented.
In a rolling oil feed system where, separately from a circulation type feed system (first rolling oil feed system), a second rolling oil feed system is provided, and emulsion having the average particle diameter larger than that in the circulation type rolling oil feed system is fed to the upper and lower faces of a strip (3), so as to improve its lubricity, the second rolling oil feed system measures or estimates the total hardness of dilution water to be mixed with the crude oil of rolling oil, based on the measured or estimated hardness value of the dilution water, regulates the total hardness of the dilution water, then, mixes the dilution water with the rolling crude oil, and controls the mixture so as to have the average particle diameter exceeding the average particle diameter of emulsion rolling oil in the first rolling oil feeding stage.
KIMURA YUKIO
Satoshi Kono
Makoto Nakamura
Kurata Masatoshi
Takashi Mine
Yoshihiro Fukuhara
Sadao Muramatsu
Ryo Hashimoto
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