A hydraulically controlled backing roller includes a mandrel, two cover plates which are installed at two ends of the mandrel through screws respectively, and two screwdown gears which are installed at two end portions of the mandrel respectively. The two screwdown gears are engaged with an output rack of a screwdown hydraulic cylinder, multiple saddle ring sets are sleeved on the mandrel at equal intervals, a saddle ring of each of the saddle ring sets is fixed with a frame through a fan-shaped plate, a backing bearing is provided between two adjacent saddle ring sets; an inner eccentric ring of the each of the saddle ring sets is driven to rotate by hydraulic driving, so that the mandrel has a deflection deformation, and the deflection deformation is transmitted to other adjacent rollers through the backing bearing.

Method for the production of flat metal products, in particular coils of strip, in endless and/or semi-endless mode, in which a metal product is continuously fed to a rolling mill consisting overall of at least 4 stands. The rolling stands are, in sequence, roughing stands, and finishing stands. It is provided to perform a flying gauge change of the metal product exiting from the rolling mill.

A primary object of the present invention is to provide a continuous-cast slab where central porosity is reduced by surly crushing the slab, and a method and apparatus of manufacturing the same.

The continuous-cast slab 1 having horizontally symmetrical granular equiaxed crystals at least in the center in the thickness direction includes a first reduction dent 2 and a second reduction dent 3 that further dents from the bottom surface of the first reduction dent 2 and is narrower than the first reduction dent 2 at least on one long side surface. Such a configuration can makes it possible to achieve the continuous-cast slab 1 of no more than 2.5×10.sup.−4 cm.sup.3/g in a maximum porosity volume while segregation is reduced.

A method disclosed herewith is a method for producing a first seamless metal tube with a first wall thickness and a second seamless metal tube with a second wall thickness by using a three-roll-type inclined rolling mill, and the method includes a first inclination rolling step (#5), a setting changing step (#10), and a second inclination rolling step (#15). At the first inclination rolling step, a first workpiece is rolled by the inclined rolling mill. At the setting changing step, a setup condition of the inclined rolling mill is changed in a manner (a) or (b) as described below. At the second inclined rolling step, a second workpiece is rolled by the inclined rolling mill under the changed condition. (a) When the second wall thickness is smaller than the first wall thickness, the cross angle of each of the inclined rolls is made greater than the cross angle set for the first inclination rolling step. (b) When the second wall thickness is larger than the first wall thickness, the cross angle of each of the inclined rolls is made smaller than the cross angle set for the first inclination rolling step.

The seamless pipe in which a thin-walled portion in a pipe circumferential direction is formed in a pipe axial direction, in which a line segment formed by connecting one end and the other end of the thin-walled portion along a pipe surface with a shortest distance in a formation direction of the thin-walled portion is inclined at an angle α of 5.0° or more with respect to the pipe axial direction. It is preferable that one end and the other end of the thin-walled portion are set from a region in a pipe selected with a shorter length between a length of 1.0 m in the pipe axial direction and 90% of a length in the pipe axial direction where the thin-walled portion turns once in the pipe circumferential direction.

The invention relates to a method for the heat treatment of a moving aluminium alloy strip, the aluminium strip has an upper-surface and a lower-surface, the method comprising moving the aluminium strip over at least two rotating heating rolls, wherein the heating rolls comprises an outer-surface, such that a surface of the aluminium strip is in heat-transfer contact with the outer-surface of the heating rolls to induce heat into the aluminium strip to heat the aluminium strip at an annealing temperature, and comprising moving the aluminium alloy strip over a first rotating heating roll followed by moving the aluminium strip over a second rotating heating roll such that alternating the upper-surface and the lower-surface of the aluminium strip are in heat-transfer contact with the outer-surface of the rotating heating rolls.

A method of controlling flatness of a strip of rolled material in a production line including a hot rolling mill and at least one cold rolling mill, downstream of the hot rolling mill, the method including determining flatness data of the strip in one or more of the at least one cold rolling mill and/or following passing of the strip through one or more of the at least one cold rolling mill; determining a thickness profile target of the strip for the hot rolling mill based on the flatness data; and passing the strip through the hot rolling mill and adjusting the thickness of the strip based on the thickness profile target. A control system and a production line are also provided.

A rolling mill is provided with: a roll for rolling a metal plate, the roll being capable of shifting in an axial direction and having a tapered portion at an end portion in the axial direction; and a heating unit configured to form an expansion portion protruding in a radial direction in the tapered portion by heating the tapered portion.

A controller (2) and method for controlling a stretch-reducing mill (1) for rolling tubes are presented. The stretch-reducing mill (1) has several roll stands (10) arranged behind one another in a conveying direction (F) of the tubes (R) and at least one outlet-side wall thickness measuring device (20). The controller (2) is set up to receive measurement data from the wall thickness measuring device (20) which identifies one or more outlet-side wall thicknesses (s.sub.r) of a tube (R) exiting from the last roll stand (10) and one or more of the received measurement data wall thickness on the inlet-side (s.sub.l_t), preferably to determine an inlet-side wall thickness profile of the tube (R) before entering the first roll stand (10), and preferably to calculate and control one or more of the roll stands (10), taking into account the determined inlet-side wall thicknesses (s.sub.l_t).

An electric resistance welded steel pipe having excellent formability and torsional fatigue resistance and a method for manufacturing the same. The electric resistance welded steel pipe includes a seam region and a base metal region, the seam region having a range of ±10 degrees in a pipe circumferential direction with respect to an electric resistance welded seam formed in a pipe longitudinal direction, the base metal region being a region other than the seam region. The electric resistance welded steel pipe has an r-value in the pipe longitudinal direction of 1.0 or greater, H (mm) and W (mm) satisfy a specified formula, and Ts.sub.(MAX) (mm) and Tb.sub.(Ave) (mm) satisfy a specified formula.