To remove a scale at hot rolling by performing high draft rolling of a hot-rolled steel strip before pickling under a stable condition without generating sheet escape and meandering.
The rotary shaft of a grinding wheel 26 is orthogonally crossed with the roll shaft of a work roll 10 which is used when the scale at hot rolling by performing high draft rolling of the hot-rolled steel strip 1 before the pickling, the grinding wheel 26 is rotated in the state where it is pressed against the peripheral surface of the work roll 10 and the peripheral surface of the work roll 10 is ground with ground marks g1 along a plane orthogonally crossed with the roll shaft. Then, because the ground marks g1 are along the plane orthogonally crossed with the roll shaft, thrust force F by which the hot-rolled steel strip 1 is moved in the width direction is not generated and the hot-rolled steel strip 1 is rolled at high draft under the stable condition.
UCHIYAMA TAKUMI
KITANI TOMOHARU
