Method and apparatus to control and adjust the drawing action in a rolling mill, and corresponding rolling mill

An apparatus to control and adjust the drawing action in a rolling mill (11) for long products (13) provided with a plurality of rolling stands (12a, 12b, 12c) located in sequence through which a product (13) being rolled passes in a direction of rolling (A), wherein it comprises:

• a video monitoring system (14) for acquiring a sequence of frames (15a, 15b, 15c) of the product (13) being rolled positioned, during use, in at least one position along said rolling mill (11);
• a processing system (16), connected to said video monitoring system (14) and configured to:
• carry out the processing of said sequence of frames (15a, 15b, 15c) and define in said sequence of frames (15a, 15b, 15c) acquired at least one normal rolling range (17) within which the product (13) being rolled has to be positioned in a situation of normal rolling;
• identify the position of the product (13) being rolled and its geometric characteristics;
• identify a possible oscillation of the product (13) being rolled as a function of a variation of the position of the product (13) being rolled over time with respect to said at least one range (17) based on the analysis of said sequence of frames (15a, 15b, 15c) acquired;
• an automation system (18) associated with the rolling mill (11), connected to said processing system (16) and configured to determine an optimal condition of the drawing action for said product (13) being rolled corresponding to a condition of minimum oscillation of said product (13) being rolled in at least one inter-stand segment and to receive data relating to the position of the product (13) being rolled and of the possible variation of position of the product (13) being rolled, so as to be able to determine the continuation of the rolling if the product (13) is correctly positioned in said normal rolling range (17), or a possible variation of one or more of the rolling parameters if the position of the product (13) being rolled is potentially able to generate a cobble, that is, it is outside of said range (17), in order to maintain or restore said optimal condition of the drawing action in said at least one inter-stand segment.