MANUFACTURING METHOD OF TUBES USING CONTINUOUS TUBE-WELDING MACHINES Russian patent published in 2015 - IPC B21C37/06 

FIELD: metallurgy.

SUBSTANCE: method involves use of strips with a width having a shrinkage margin as to width at deformation, butt welding of ends of strips to a continuous strip, its deformation by alternating-sign plastic bending with tension with non-driven rolls of a multiroll bending-tensioning device, drawing through this device of the strip with a pulling mechanism, moulding of the strip into a tube workpiece, welding of its edges and calibration or shaping of a welded tube. Actual drawing value of the strip in the bending-tensioning device is determined. Thickness of the strip is measured at the inlet of the bending-tensioning device; drawing value is calculated for sections of the strip with thickness of more than H"гран" and drawing value for its sections with thickness in the range of hmin to H"гран" and its drawing is controlled by changing the total value of angles of all bends of the strip so that the actual drawing value is equal to its design value. The above parameters are subject to mathematical relationships.

EFFECT: improving a deformation degree of a strip and reducing metal consumption.

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