METHOD FOR MANUFACTURING THIN-WALLED VESSEL-TYPE ARTICLE AND BILLET FOR COMPLEX DRAWING OF SLEEVE Russian patent published in 1995 - IPC

FIELD: plastic working of metals. SUBSTANCE: method involves manufacturing inner pressure loaded thin-walled vessel-type article from round billet by stamping sleeve with bottom and forming throat, with bottom being preliminarily stamped to obtain plate-shaped semifinished product without changing billet diameter by forcing excessive metal from central portion into peripheral portions so that depression is formed on inner side. Depression surface shape is made identical to that of end and toroidal parts of punch and peripheral part outer side of billet is made in the form of truncated cone. Sleeve is stamped by complex drawing so that conical surface of semifinished product peripheral part coincides with identical surface of die working part and punch is centered so that its end and toroidal surfaces coincide with respective depression surfaces. Then final stamping of bottom part is provided. Billet is made in the form of plate with depression, whose surface conforms with respective end and toroidal surfaces of cavity of sleeve drawn from billet, with plate bottom thickness being less than that of peripheral part. Billet peripheral part has annular thickened portion, with thickness smoothly increasing from depression edge to maximum value and then smoothly decreasing towards billet edge. Outer surface of billet peripheral part is made in the form of truncated cone, whose lesser end diameter does not exceed diameter of sleeve drawn from billet. EFFECT: improved quality of vessels. 3 cl, 4 dwg