Abstract: This circular rolling mill has a fixed main frame, a pair of cylindrical rollers, internal and external, to shape internal and external radial faces of an annular part and supported by a first secondary frame mounted on the main frame, as well as a pair of conical rollers, upper and lower, to shape opposite front faces of the part and supported by a second secondary frame mounted on the main frame. At least one rack and pinion assembly moves a roller in translation relative to one of the secondary frames. At least one electric geared motor drives the pinion of the rack and pinion assembly. The electric geared motor is fixedly mounted relative to one of the auxiliary frames. A fluid discharge mechanism is interposed in a kinematic chain for transmitting force between the rack and the roller moved by this rack. The fluid discharge mechanism has at least one variable volume chamber supplied with pressurized fluid and the volume of which varies as a function of the relative position of the roller and of the rack.

Abstract: A thickness control apparatus of a reversing rolling mill has an entry thickness gauge that measures the thickness of the material to be rolled, and entry material speed detector that detects the speed of the material to be rolled. Measured thickness measured by the entry thickness gauge is tracked on the basis of the speed of the material to be rolled detected by the entry material speed detector. A mill delivery thickness calculator calculates thickness on the delivery side of the reversing rolling mill on the basis of the thickness on the entry side and the roll gap detected.

Abstract: A flaw detection apparatus and flaw detection method for automatically detecting the occurrence of a flaw in a mother tube manufactured by rolling a hollow shell using a mandrel mill are provided. A flaw detection apparatus (100) according to the present invention includes a wall thickness gauge (1) which is installed on the exit side of a mandrel mill (M) and which measures the tube wall thickness in each of the reducing directions of a hollow shell (P) in the #1-#5 stands of the mandrel mill, rolling load measuring devices (2) which measure the rolling load in the #1-#5 stands, and a decision unit (3) which determines whether there are flaws in the mother tube based on the measured value of the tube wall thickness in each of the reducing directions of the hollow shell (P) and the measured value of the rolling load in each stand.

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: Method for determining an intermediary profile of a metal strip between an upstream and a downstream roll stand in a mill train having at least two roll stands is described intermediary profile (pout) and the final profile (pout) of the metal strip downstream from the downstream roll stand are determined using an analytical model with parameters. The final profile is determined using a final profile model. At least one parameter is modified so that the difference between the final profile, determined using an analytical model, and the final profile, determined using the final profile model, is reduced.