PROCEDURE FOR PRODUCTION OF PIPES WITH PROFILED EDGE LINES Russian patent published in 2010 - IPC B21D53/08 B21D41/00 F28F1/00 

FIELD: metallurgy.

SUBSTANCE: invention refers to treatment under pressure, particularly to production of pipes with profiled edge lines using effect of localised directed plastic deformation of pipe material. Upon preparing operations the end of the pipe is positioned in a cavity of a split matrix with smooth working surface. The pipe is fixed against possible travels; a small step of a mandrel is inserted into the cavity of the pipe. The working tooth of the mandrel is transferred relative to the pipe causing local plastic deformation of pipe material which fills the gap between internal diametre of the pipe and the small step of the mandrel. Thus an internal boss is formed on the internal surface of the pipe and simultaneously the end of the pipe is calibrated by external diametre. Further, the end of the pipe is positioned into the split matrix with placing the internal boss opposite a finished engraving; the end of the pipe is radially squeezed, also the said finish engraving is preliminary filled with material of the pipe. Finally a band in the finish engraving of the matrix is formed by means of mandrelling the squeezed section of the pipe.

EFFECT: upgraded quality of produced items.

6 dwg