Abstract: A method and a device is provided for controlling the overlapping of leveling rollers in a planishing machine comprising two leveling trains each bearing a series of rollers with parallel axes. The method and device are particularly applicable to sheets and strip products of great thickness and high hardness requiring little roller overlap. The method is characterized in that it consists in measuring at least the overall value of the torques transmitted to the planishing rollers by the motors, in determining the actual value of the torques used for planishing the product, in comparing the determined value with the reference value of the torque provided by the presetting model and in acting on the members regulating the roller overlap to maintain the value of the thus determined torque at the reference value.

Abstract: A method regulating flatness of a metal strip at a roll housing output including at least one dynamic flatness actuator. A rolling process characterizes flatness of the strip by measuring a quantity D in n points distributed across the strip width, from n measurements of the quantity D. Then, using an action model of flatness regulation and an optimizing method, an overall setpoint including at least one elementary setpoint is determined for the dynamic actuator, such that a calculated flatness residual defect criterion is minimal, and executing the overall setpoint. The action model on the flatness used for determining the overall setpoint includes, for the dynamic actuator, as many submodels as there are points for measuring the quantity D characteristic of flatness, each submodel enabling the effect of the dynamic actuator on the quantity D to be calculated at the corresponding point when a setpoint is applied thereto.

Abstract: The invention concerns a method and a device for controlling the overlapping of levelling rollers in a planishing machine comprising two levelling trains each bearing a series of rollers (4, 4?) with parallel axes. The invention is particularly applicable to sheets and strip products of great thickness and high hardness requiring little roller overlap. The method is characterized in that it consists in measuring at least the overall value of the torques transmitted to the planishing rollers by the motors, in determining the actual value of the torques used for planishing the product, in comparing the determined value with the reference value of the torque provided by the presetting model and in acting on the members (3, 3?) regulating the roller overlap to maintain the value of the thus determined torque at the reference value (Refc).

Abstract: A method regulating flatness of a metal strip at a roll housing output including at least one dynamic flatness actuator. A rolling process characterizes flatness of the strip by measuring a quantity D in n points distributed across the strip width, from n measurements of the quantity D. Then, using an action model of flatness regulation and an optimizing method, an overall setpoint including at least one elementary setpoint is determined for the dynamic actuator, such that a calculated flatness residual defect criterion is minimal, and executing the overall setpoint. The action model on the flatness used for determining the overall setpoint includes, for the dynamic actuator, as many submodels as there are points for measuring the quantity D characteristic of flatness, each submodel enabling the effect of the dynamic actuator on the quantity D to be calculated at the corresponding point when a setpoint is applied thereto.

Abstract: The invention relates to a damping method and device for a roll stand to reduce the sensitivity to chatter thereof. In the method of the invention the absorption is conducted by a chatter mass (8) situated above each post (2) forming the roll stand (1) and the vibration energy is dissipated in a mattress (83) of an incompressible fluid forming a direct link between each post (2) and the chatter mass (8) According to the invention the fluid mattress is kept in a steady flow by supply means (91) and exhaust means of adjustable caliber (92). The frequency response of the system and its damping coefficient are set by the dimensioning of the chatter mass (8), the control of the thickness (h) of the fluid mattress and its flow rate via the calibrated orifice (92).

Abstract: The invention relates to a process for rolling a metal product by successive passes into at least one roll stand associated with a calculation unit comprising a computer and a mathematical model for adjusting the rolling load applied by the clamping means. According to the invention, before each pass, the computer associated with the mathematical model determines a predictable variation value of the flow stress of the metal corresponding to the deformation to be realized in the pass considered, while taking into account the evolution, during the rolling operation, of the microcrystalline structure of the metal making up the product to be rolled, and the rolling load to be applied in order to achieve the requested reduction in thickness is calculated before each pass according to the value thus predicted for the flow stress and the evolution of the microcrystalline during the rolling operation.

Abstract: Control process for twin-roll continuous casting, in which, during casting, the roll separation force (RSF) is measured and the position of the bearings of at least one of the rolls is varied in order to increase or decrease the center-to-center spacing of the rolls, with a view to keeping the force substantially constant, a band (.DELTA.RSF) of force values bracketing a desired nominal force (RSF.sub.0) is predetermined and the position of the bearings is varied more sharply when the value of the measured force lies outside the band than when it lies within the band. Application especially to the twin-roll continuous casting of thin steel strip.

Abstract: Device for setting of the position of the cylinders of a rolling mill whose gripping is regulated by hydraulic jacks. The device essentially comprises a tubular sleeve which surrounds a measuring rod, making no contact therewith, and moves in the same manner as the latter, being fixed to one of the elements of the hydraulic jack for gripping the cylinders of rolling mills, and sliding in an aperture pierced in the other element of the jack.