Abstract: A method and device for controlling the final thickness of a rolled product at a tandem rolling mill exit which make it possible to remove the cyclic defects of the product thickness variation. The method includes using at least one rolling stand provided with hydraulic adjustment devices located on the tandem rolling mill exit and in compensating the cyclic defects of the product thickness variation generated upstream through the entire rolling mill on the stand with the aid of an adjuster (R) coordinated with the frequency of defects. The method and device are suitable for tandem cold rolling mills producing metal strips. The thickness defects are detectable by a thickness sensor.

Abstract: A method and device for controlling the final thickness of a rolled product at a tandem rolling mill exit which make it possible to remove the cyclic defects of the product thickness variation. The method includes using at least one rolling stand provided with hydraulic adjustment devices located on the tandem rolling mill exit and in compensating the cyclic defects of the product thickness variation generated upstream through the entire rolling mill on the stand with the aid of an adjuster (R) coordinated with the frequency of defects. The method and device are suitable for tandem cold rolling mills producing metal strips. The thickness defects are detectable by a thickness sensor.

Abstract: The invention relates to a method for detecting the vibrations of a roll stand (1) equipped with a hydraulic jack (6) as a device for adjusting the rolling rolls (4, 5). The hydraulic jack comprises a sensor (64) for measuring the position of the mobile portion relative to the fixed portion, this sensor supplying a digital signal (POS). In the method of the invention, the vibrations are detected by direct observation of the position signal (POS) and a comparison thereof relative to a spatio-temporal window (F) whose dimensions are determined as a function of the frequency to be detected. In accordance with the invention, it is possible to define different observation windows (F) suitable for the detection of different vibratory phenomena.

Abstract: The invention relates to a method for detecting the vibrations of a roll stand (1) equipped with a hydraulic jack (6) as a device for adjusting the rolling rolls (4, 5). The hydraulic jack comprises a sensor (64) for measuring the position of the mobile portion relative to the fixed portion, this sensor supplying a digital signal (POS). In the method of the invention, the vibrations are detected by direct observation of the position signal (POS) and a comparison thereof relative to a spatio-temporal window (F) whose dimensions are determined as a function of the frequency to be detected. In accordance with the invention, it is possible to define different observation windows (F) suitable for the detection of different vibratory phenomena.

Abstract: The invention relates to a method and a device for controlling the final thickness of a rolled product (B) at the outlet of a rolling mill including at least two roll stands (1–5) operating in tandem and associated with a general speed control system of the different stands, and to a device for controlling the reduction in thickness and in tension of the product (B) in each space (10–50) between two successive stands. According to the invention, the control device performs, in real time, dynamic balance, between the different stands (1–5), of the torques applied, in each stand, on the working rolls (T, T?), without any noticeable disturbance of the final thickness h5 of the product (B) at the outlet of the plant. The invention enables, in particular, to optimise the productivity of a tandem rolling mill, without any engine overloading risks.

Abstract: The invention relates to a method and a device for controlling the final thickness of a rolled product (B) at the outlet of a rolling mill including at least two roll stands (1-5) operating in tandem and associated with a general speed control system of the different stands, and to a device for controlling the reduction in thickness and in tension of the product (B) in each space (10-50) between two successive stands.

Abstract: The process is characterized in that, before starting casting, an initialization position is determined for the stopper rod control actuator when the stopper rod is resting on its seat under its own weight and after having filled the tundish equipped with this stopper rod, the actuator is operated to place it in a controlled superclosed position and, to start casting, the actuator is driven according to an imposed movement versus time law, time (t1) for start of casting being determined from this law and the control actuator continues to be driven in opening direction to enable the metal to flow into the ingot mould.