A device for guiding and directing a metal sheet in a bending machine to form continuously a conical structure, in particular a frustoconical structure, comprises: resting and contrasting arrangement extending along a closed path, and suitable for restingly receiving a longitudinal edge of the metal sheet and contrasting a movement of the edge in a direction that is transverse to a preset advancement trajectory of the metal sheet; a supporting body for the resting and contrasting arrangement, having at least one oblong lateral portion that is suitable for facing the edge and configured for conforming the resting and contrasting arrangement to the longitudinal profile of the edge so as to obtain an extended zone of contact with said edge and impose resting and contrasting pressure distributed along the edge; the resting and contrasting arrangement is movable around the supporting body along the closed path to accompany the edge of the metal sheet by a distributed contact devoid of relative sliding and rolling, so as to impose on the metal sheet the advancement along the desired advancement trajectory to and through the bending machine. The corresponding method is also provided.

To a fulcrum roll unit portion in a workpiece, a corresponding initial curvature radius is applied, and to a bending roll unit portion in a workpiece, a corresponding design curvature radius is applied. To an intermediate unit portion in a workpiece, an intermediate curvature radius set so as to continuously change from the initial curvature radius to the design curvature radius is applied. At least one of the fulcrum roll and the bending roll is moved on the basis of an integrated value obtained by integrating the amount of change in bending position in each of the intermediate unit portion and the bending roll unit portion.

To a fulcrum roll unit portion in a workpiece, a corresponding initial curvature radius is applied, and to a bending roll unit portion in a workpiece, a corresponding design curvature radius is applied. To an intermediate unit portion in a workpiece, an intermediate curvature radius set so as to continuously change from the initial curvature radius to the design curvature radius is applied. At least one of the fulcrum roll and the bending roll is moved on the basis of an integrated value obtained by integrating the amount of change in bending position in each of the intermediate unit portion and the bending roll unit portion.

To a fulcrum roll unit portion in a workpiece, a corresponding initial curvature radius is applied, and to a bending roll unit portion in a workpiece, a corresponding design curvature radius is applied. To an intermediate unit portion in a workpiece, an intermediate curvature radius set so as to continuously change from the initial curvature radius to the design curvature radius is applied. At least one of the fulcrum roll and the bending roll is moved on the basis of an integrated value obtained by integrating the amount of change in bending position in each of the intermediate unit portion and the bending roll unit portion.

To a fulcrum roll unit portion in a workpiece, a corresponding initial curvature radius is applied, and to a bending roll unit portion in a workpiece, a corresponding design curvature radius is applied. To an intermediate unit portion in a workpiece, an intermediate curvature radius set so as to continuously change from the initial curvature radius to the design curvature radius is applied. At least one of the fulcrum roll and the bending roll is moved on the basis of an integrated value obtained by integrating the amount of change in bending position in each of the intermediate unit portion and the bending roll unit portion.

A method for curving an elongated piece uses a digital system which includes a control console having a programmable processing unit and a screen for displaying data and a camera connected with the processing unit and configured and positioned for acquiring images of the elongated piece. In accordance with the method, the profile of at least one virtual template of curvature is stored in the processing unit and a real image of the elongated piece is detected. The profile of the virtual template and the real image of the elongated piece are reproduced and compared in real time. The roller curving machine is driven and the curvature and the geometric configuration of the elongated piece are matched with the profile of the virtual template of curvature.

A side trimming device according to an embodiment of the present invention may comprise: a cutting unit for mechanically cutting a transferred steel plate; a groove forming unit for forming a groove in a cutting-scheduled area in front of the cutting unit with reference to the steel plate transfer direction; and a washing unit arranged adjacent to the groove forming unit so as to suction molten material accumulating in the groove in the side direction of the steel plate.

A side trimming device according to an embodiment of the present invention may comprise: a cutting unit for mechanically cutting a transferred steel plate; a groove forming unit for forming a groove in a cutting-scheduled area in front of the cutting unit with reference to the steel plate transfer direction; and a washing unit arranged adjacent to the groove forming unit so as to suction molten material accumulating in the groove in the side direction of the steel plate.

In a method for setting bending of at least one straightening roller in a roller straightening machine, the straightening roller is supported by a plurality of supporting roller devices arranged beside one another in the axial direction, wherein each supporting roller device can be adjusted by an actuating device such that stresses are produced in the straightening roller. To control the actuating device, a control system is provided, by which the adjustment of the supporting roller device can be set manually. Limiting values (vMA, vMI) with respect to the stresses produced in the straightening roller are stored in the control system. In the event of adjustment of one of the supporting roller devices, maxima (MA) and minima (MI) of the stresses produced in the straightening roller are calculated and it is checked whether the maxima (MA) and minima (MI) lie within the limiting values (vMA, vMI).

An apparatus for forming a round or oval shaped duct for all AC systems in one continuous operation where two driving rolls advance a flat metal sheet to at least one multi-positioning bending roll, where the at least one bending roll is moveable to a bending position for different curvatures and a non-bending position. The driving rolls advance the sheet through while the bending roll bends the sheet to form the curved sides, and the bending roll in the non-bending position form the flat sides of the oval shaped duct. A position sensor detects the position of the flat metal sheet in the rolls to control the location along the sheet where the bending roll is moved to either of the bending or non-bending positions while the driving rolls are stopped. An adhesive dispenser joins both ends of the sheet, resulting in a complete duct.