TUBE PRODUCTION METHOD Russian patent published in 2007 - IPC B21C1/00 

FIELD: processes for making tubes with the same or different thickness of walls.

SUBSTANCE: method comprises steps of drawing tube blank through drawing die or drawing and rolling tube blank; at first flattening initial blank and thinning its wall thickness at thinning factor in range 1 - 20 by drawing initial tube blank through drawing dies or by drawing and rolling it between rollers at providing contact of inner walls of tube; then shaping worked tube by imparting predetermined profile to each cross section of tube. It is possible to flatten tube only in its several zones. Heat treatment may be also realized. Invention provides production of tubes with different thickness of their walls that may be changed in cross section of tube and also along its length, tube with different profile of their cross section and tubes with very thin walls.

EFFECT: enlarged functional possibilities, simplified manufacturing process and equipment.

7 cl, 9 dwg