PROCEDURE FOR SHAPING BOX AND TUBE-LIKE ITEMS WITH LUGS AND PUNCH FOR IMPLEMENTATION OF THIS PROCEDURE Russian patent published in 2010 - IPC B21D5/01 B21D11/18 B21D37/02 

FIELD: metallurgy.

SUBSTANCE: invention refers to metal forming operations and can be implemented at various branches of industry (machine building, ship building etc) at fabrication of box and tube-like items out of sheet metal and tubes. The procedure consists in bending sheet work-piece per several passes. Lengthwise edges are alternately bent at the first pass. During the second pass the work-piece is bent from each bent lengthwise edge to the middle of the work-piece. Simultaneously there are formed specified curvature and lugs in lengthwise direction. Further, the middle part of the work piece is bent in cross direction. During successive passes lugs from one side of the work-piece to its middle are bent from edges made at the first pass. The same is made from the other end to the middle of the work-piece with increase of applied load to a maximal in the middle part of the work-piece. The punch consists of interacting upper and lower deforming units in form of a puncheon and matrix. Working surfaces of the puncheon and matrix correspond to cross and lengthwise section of item by shape. The puncheon and the matrix are made with lugs corresponding to lugs on items and with recesses. The recesses are located between the lugs and do not contact the item.

EFFECT: reduced labour input at shaping work-pieces of big thickness and reduced consumption of material.

7 cl, 1 ex, 3 dwg