LOW-WASTE CUTTING OF TRAPEZOIDAL BLANKS FROM SHEET REEL, TAPE OR STRIP (VERSIONS) Russian patent published in 2015 - IPC B21D28/02 

FIELD: process engineering.

SUBSTANCE: invention relates to metallurgy. Proposed process comprises cutting of four or two polygonal wastes with one side making the part of reel edge. Vertex of triangular cutout opposite the reel edge is rounded by line. Line length is defined proceeding from high hardness of waste cutting blade. Two lateral sides of triangular cutout are straight or arched with sizes corresponding to sweep of angular sections of finished spatial part in plan. Features of workpiece plastic deformation and allowances at semis at production of this part are considered. At second step, trapezoidal workpiece, second from reel end, is cut in two straight unparallel lines. Lines cross the four vertices of four triangular cutouts Trapezoidal workpiece, first from the reel end, is cut in straight line, said workpiece being turned relative to second workpiece. This reel is fed through a stroke. The next wastes cutting cycle is performed over two reel edges and two trapezoidal work pieces turned toward each other. Shaped work pieces are cut with previous workpiece outline fed into that of the next workpiece.

EFFECT: higher precision of cut part, saving of sheet material.

5 cl, 5 dwg