Meandering control device for rolling line

A meandering control device for a rolling line, the device comprising:

• a tail end roll force calculator that calculates a predictive value of roll force applied to a material to be rolled by a rolling stand when entry side tension is not applied, based on the roll force applied to the material to be rolled by the rolling stand, entry side tension applied to the material to be rolled at an entry side of the rolling stand, delivery side tension applied to the material to be rolled at a delivery side of the rolling stand, and temperature of the material to be rolled;
• an allowable meandering amount roll force calculator that calculates a reference value of the roll force applied to the material to be rolled when a meandering amount of the material to be rolled is an allowable amount, based on the allowable amount of the meandering of the material to be rolled when the entry side tension is not applied, a difference in the roll force applied to the material to be rolled by the rolling stand between one side and another side, and velocity of the material to be rolled at the entry side of the rolling stand;
• a temperature rise amount calculator that calculates a temperature rise amount of the material to be rolled, based on a difference between the predictive value of the roll force calculated by the tail end roll force calculator and the reference value of the roll force calculated by the allowable meandering amount roll force calculator and outputs, a signal corresponding to the temperature rise amount;
• a bar heater controller that controls a bar heater before the entry side of the rolling stand that heats the material to be rolled in accordance with the signal output by the temperature rise amount calculator to suppress meandering of the material when being rolled;
• a temperature rise amount shortage meandering amount calculator that, when the temperature rise amount of the material to be rolled calculated by the temperature rise amount calculator exceeds a heating temperature that the bar heater can reach, calculates a meandering amount of the material to be rolled corresponding to a temperature rise amount shortage exceeding the heating temperature that the bar heater can reach;
• a leveling unit operation amount calculator that calculates an operation amount of a leveling unit that adjusts the rolling stand so as to offset the meandering amount of the material to be rolled corresponding to the temperature rise amount shortage exceeding the heating temperature that the bar heater can reach;
• the bar heater controller controls the bar heater in accordance with the heating temperature that the bar heater can reach;
• and
• a leveling unit controller operating the leveling unit in accordance with the operation amount output from the leveling unit operation amount calculator.