METHOD OF PRODUCING SHELLS WITH LONGITUDINAL RIBS ON OUTER SURFACE Russian patent published in 2024 - IPC B21C37/20 B21J5/12 B21J13/02 B21K21/06 

FIELD: metal forming.

SUBSTANCE: invention relates to metal forming, particularly, to production of shell-type parts with lengthwise ribs on outer surface. Method of producing shells with longitudinal ribs on the outer surface includes forming a workpiece in two successive drawing operations, at that, at the first operation, a combined drawing is performed with the formation of a sheet workpiece in the form of a disk, which is pre-installed in the lead-in part of the die for the combined drawing, shell semi-finished product due to simultaneous movement of internal and external puncheons fixed on press sliders, at the end of the first operation the external puncheon is stopped, wherein the movement of the inner puncheon is continued, with the help of which the second operation of the combined drawing is performed with local thinning of the wall and the formation of longitudinal ribs in the shaped matrix, having recesses with a depth equal to the height of the longitudinal ribs of the finished shell, with a coefficient of local thinning equal to m_s2=1-h/S₁, where m_s2 is coefficient of local thinning; h is the height of the longitudinal ribs of the finished shell, mm; S₂ – finished shell wall thickness, mm; S₁ – shell semi-finished product wall thickness, mm, wherein, before successive drawing operations, an intermediate ring is fitted between the die for combined drawing and the forming die to make the distance between the dies greater than the height of the shell semi-finished product.

EFFECT: expansion of technological capabilities of the method for production of shells with possibility of obtaining shells with longitudinal ribs on the outer surface from a sheet workpiece in the form of a disk.

1 cl, 7 dwg