Temperature control system and temperature control method for hot rolling line

A system for controlling temperature of a material to be rolled in a hot rolling line, the hot rolling line including a rougher mill for performing a reverse rolling, a finisher mill for performing a tandem rolling, an intermediate equipment group provided between the rougher mill and the finisher mill, a rougher delivery-side pyrometer provided between the rougher mill and the intermediate equipment group, a finisher entry-side pyrometer provided between the finisher mill and the intermediate equipment group, and a control device,

• wherein the intermediate equipment group includes a cooling equipment for cooling the material to be rolled using coolant water,
• wherein the control device comprises:
• a set-up calculation device configured to determine a flow amount set-up value of the coolant water in the cooling equipment;
• a feedforward control device configured to perform feedforward control of the flow amount of the coolant water in the cooling equipment based on the flow amount set-up value;
• and
• a learning device configured to calculate a learning value based on a flow amount measured value of the coolant water in the cooling equipment and a finisher entry-side temperature measured value indicating a measured value of temperature of the material to be rolled measured by the finisher entry-side pyrometer,
• wherein the set-up calculation device is configured to:
• determine a finisher entry-side temperature target value indicating a target value of the temperature of the material to be rolled at an entry side of the finisher mill before a final pass of the reverse rolling on the material to be rolled is performed;
• calculate a cooling equipment delivery-side temperature target value indicating a target value of the temperature of the material to be rolled at a delivery side of the cooling equipment for a finisher entry-side temperature prediction value indicating a predicted value of the temperature of the material to be rolled at the entry side of the finisher mill to match the finisher entry-side temperature target value;
• and
• determine the flow amount set-up value based on the cooling equipment delivery-side temperature target value and the learning value,
• wherein the feedforward control device is configured to:
• determine a target temperature pattern indicating a pattern of target values of the temperature of the material to be rolled over whole length of the material to be rolled at the delivery side of the cooling equipment;
• and
• calculate flow amount standard values of the coolant water in the cooling equipment for each point in a longitudinal direction of the material to be rolled based on the flow amount set-up value, velocity information of the rougher mill, and a rougher delivery-side temperature measured value indicating a measured value of the temperature of the material to be rolled measured by the rougher delivery-side pyrometer,
• wherein the flow amount standard values are calculated such that a temperature prediction value of the delivery side of the cooling equipment indicating a predicted value of the temperature of the material to be rolled at the delivery side of the cooling equipment is consistent with the target temperature pattern,
• wherein the feedforward control device is further configured to:
• perform the feedforward control such that flow amounts of the coolant water in the cooling equipment when each point of the material to be rolled reaches position to be cooled by the cooling equipment are respectively consistent with the flow amount standard values calculated for each point of the material to be rolled,
• wherein the learning device is configured to calculate the learning value based on a difference between the finisher entry-side temperature measured value and a finisher entry-side temperature re-prediction value indicating a re-prediction value of the temperature of the material to be rolled at the entry side of the finisher mill,
• wherein the finisher entry-side temperature re-prediction value is calculated based on the flow amount measured value, the rougher delivery-side temperature measured value, and an actual velocity of the material to be rolled.