METHOD FOR MANUFACTURING A GRID OF CORRUGATIONS ON THE INNER SURFACE OF A CYLINDRICAL SHELL Russian patent published in 2023 - IPC B21C37/20 B21J5/12 B21K21/16 

FIELD: metals processing.

SUBSTANCE: invention relates to the processing of metals by pressure and can be used in the production of cylindrical shells with notches on the inner surface. The shell is installed in a container and shaping is carried out on its inner surface of a grid of diamond-shaped corrugations by a hollow working mandrel with spiral wedge protrusions in two operations. In the first operation, spiral riffles are formed. Before the second operation, the working mandrel is reset to the opposite helix angle of the helical protrusions. In the second operation, spiral corrugations are formed with the opposite angle of elevation. At each operation, the inner surface of the shell is first burnished with a mandrel with a working diameter exceeding the diameter of the shell. Then corrugations are formed by a working mandrel with spiral protrusions with a gap between the inner surface of the shell and the diameter of the working mandrel along the base of the wedge protrusions, the corrugated surface is burnished with a mandrel and the subsequent movement of the tool rod in the opposite direction with simultaneous burnishing and rotation of the working mandrel around the axis.

EFFECT: product quality is improved.

1 cl, 2 dwg, 1 ex