METHOD FOR INJECTING COOLANT FOR ROLLING ROLL

PURPOSE: To satisfy basic functions of a roll coolant and to prevent generation of roll scratch. CONSTITUTION: In the method of injecting a coolant by an injection nozzle to the rolls of a rolling mill, a nozzle 9 for removing foreign matters is provided other than a nozzle 7 for cooling, for example, and foreign matters on the roll surface is removed by injecting the coolant in the direction opposite to the rotation of a roll 5, within the area on the surface of the roll 5 and on the upstream side of the rotating direction of the roll 5 from the line OT that links the axial center of the roll 5 and the injection nozzle 9 for removing foreign matters.