To provide a cold rolling method for preventing roll marks, which are caused in a BA-finished stainless steel strip, of impression defects from occurring by contact of a work roll with a first intermediate roll.
(1) The impact force when the work roll 1 collides with the 1st intermediate roll 2 is reduced by defining the reduction rate as 0.3-0.7 cm/s. (2) The hardness difference is provided between two rolls by making the hardness of the work roll 1 higher ≥3 Hs by Shore hardness than the hardness of the 1st intermediate roll 2. (3) Hot die steel is used for the 1st intermediate roll 2. (4) The AS-U of a backing bearing 4 is flattened and rolling force is added. When each item of (1)-(4) is executed individually or by two or three items, the generation of the roll marks of the impression defects is remarkably reduced and, when all the four items are executed, the roll marks of the impression defects are completely eliminated.
KOBAYASHI HIROKAZU
CHIYUUJIYOU NORIYUKI
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