METHOD OF TUBE PRODUCTION AT TUBE CONTINUOUS WELDING MACHINES Russian patent published in 2011 - IPC B21C37/06 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming, particularly, to tube welding at tube continuous welding machines. Proposed method comprises butt welding of strip ends of separate coil into continuous strip and its deforming with rear and front tensioning by appropriate tensioning and drawing devices. Drawing device is used to draw the strip between three idle rolls of bending device overcoming its rear tensioning and deforming in said rolls. Clearance between extreme rolls makes less than two thicknesses of the strip. Central roll is embraced by strip through more than 180° has diametre smaller than that of extreme rolls. Strip tensioning presses central roll with strip embracing it to extreme rolls. Strip deformation is adjusted by varying strip rear tensioning from 0 to 0.85 of strip material yield point. Deformed strip is formed into tube billet, strip edges are welded and sized, or welded tube is shaped into finished tube.

EFFECT: higher accuracy of tube wall thickness, reduced consumption of metal, preset elongation of tube metal.

3 cl, 1 tbl, 1 ex, 1 dwg