To provide barrel-shaped piercer rolls with which shearing strain in the circumferential direction is reduced.

In these barrel-shaped piercer rolls for reducing shearing strain in the circumferential direction, when piercing a billet by using the barrel-shaped piercer roll, by setting gorge positions so that deviated width from the mill center is ≤10% of the roll length, expanding action to a material to be pierced is increased and the material to be pierced is expanded, the shearing strain is reduced. Furthermore, in the barrel-shaped piercer rolls for reducing the shearing strain in the circumferential direction, a profile is made so as to have strong shell restrain on the outlet of the roll.

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