METHOD OF MANUFACTURING OF HOLLOW CYLINDRICAL PRODUCTS Russian patent published in 2015 - IPC B21D22/20 

FIELD: machine building.

SUBSTANCE: cylindrical products are drawn-down from flat plate blanks. At that sheet blanks are used, they have same outside diameter, one has disk shape, and other have shape of rings with same size. From the disk-shape blank the first, partially deformed blank with flat ring area is produced. Then to the external surface of the ring flat area of the said partially deformed blank the ring-shaped blank is welded, its internal diameter is equal to the outside diameter of the said flat area. Drawing-out of the produced blank is continued until receiving of the partially deformed blank with flat area, its outside diameter is equal to the outside diameter of the flat area of the first partially deformed blank. Further successive welding of the ring-shaped blank to the flat area of the partially deformed blank is performed, and further drawing-down is performed until finished product manufacturing. At that all rings are subjected to same deformation.

EFFECT: extended process possibilities due to production of long cylindrical products.

3 cl, 7 dwg