Provided are: an upper work roll, radial bearings and a thrust bearing provided on a work side and a drive side of the upper work roll and supporting the upper work roll. Shift cylinders are provided on the work side of the upper work roll and apply forces in both a work side direction and a drive side direction to the thrust bearing. Shift cylinders are also provided on the drive side of the upper work roll and apply forces in both the work side direction and the drive side direction to the radial bearing 790B. The shift cylinders each apply a force in the same direction to the radial bearing and the thrust bearing when the upper work roll does not shift in an axial direction at least during rolling.

Provided are: an upper work roll, radial bearings and a thrust bearing provided on a work side and a drive side of the upper work roll and supporting the upper work roll. Shift cylinders are provided on the work side of the upper work roll and apply forces in both a work side direction and a drive side direction to the thrust bearing. Shift cylinders are also provided on the drive side of the upper work roll and apply forces in both the work side direction and the drive side direction to the radial bearing 790B. The shift cylinders each apply a force in the same direction to the radial bearing and the thrust bearing when the upper work roll does not shift in an axial direction at least during rolling.

Provided are a plurality of hydraulic cylinders including drive side shift cylinders and work side shift cylinders all configured so as to apply force in an axial direction to a top work roll. The position of the top work roll in the axial direction is held by the drive side shift cylinders and the work side shift cylinders being moved in respective axial directions. The hydraulic circuit is configured such that, after the hydraulic circuit holds the position of the top work roll in the axial direction, in a case where the hydraulic cylinders from between the drive side shift cylinders or between the work side shift cylinders are put, by external force acting upon the top work roll, into a state in which the one hydraulic cylinder applies force in the axial direction to the top work roll, the other hydraulic cylinders are moved in the opposite direction.

Provided are a plurality of hydraulic cylinders including drive side shift cylinders and work side shift cylinders all configured so as to apply force in an axial direction to a top work roll. The position of the top work roll in the axial direction is held by the drive side shift cylinders and the work side shift cylinders being moved in respective axial directions. The hydraulic circuit is configured such that, after the hydraulic circuit holds the position of the top work roll in the axial direction, in a case where the hydraulic cylinders from between the drive side shift cylinders or between the work side shift cylinders are put, by external force acting upon the top work roll, into a state in which the one hydraulic cylinder applies force in the axial direction to the top work roll, the other hydraulic cylinders are moved in the opposite direction.