METHOD FOR MANUFACTURING LONGITUDINAL ELECTRIC-WELDED PIPES Russian patent published in 2021 - IPC B21C37/08 

FIELD: pipes manufacturing.

SUBSTANCE: invention relates to the manufacture of longitudinal electric-welded pipes. The strip is rolled into a tubular billet in stands with open and closed grooves, followed by welding of its edges. A five-stage rolling of the strip is carried out in stands with an open groove. In this case, transverse bending of the edge, intermediate and central sections of the strip is performed alternately along the transitions. The values ​​of the width of each of the edge and intermediate sections of the strip and the value of half the width of the central section of the strip are equal to or differ from each other by no more than 12% from the larger of the indicated values.

EFFECT: increase in the uniformity of the distribution of longitudinal deformations along the width of the strip during its transverse bending in stands with an open groove is ensured.

10 cl, 11 dwg, 1 tbl