DEVICE FOR OBTAINING A GRID OF RIFLES ON THE INNER SURFACE OF THE SHELL Russian patent published in 2023 - IPC B21C37/20 B21H7/18 B24B39/02 B21D17/00 

FIELD: cylindrical shells.

SUBSTANCE: invention relates to a device for making a grid of corrugations on the inner surface of a cylindrical shell. The device contains a container, an ejector, a puller, springs, a cover, a tool rod, a working mandrel with spiral wedge projections, thrust bearings and a fixing screw. The tool rod is made with a working step, on which an upper mandrel with a working surface diameter D_d2, an upper thrust bearing, a working mandrel with spiral wedge protrusions, a lower thrust bearing and a lower mandrel D_d1 fixed in the tool rod with a locking screw are fixed. The diameters of the working surfaces of the lower and upper mandrel are made in accordance with the diametrical dimension D_in of the cavity of the finished cylindrical shell: D_d1=D_d2=D_in≥D_z, where D_z is the inner diameter of the cylindrical shell before its processing. The working mandrel is made with the possibility of rotation around the axis. Spiral wedge protrusions of the working mandrel are made with a height h+z, where z is the gap between the cavity of the finished cylindrical shell with a diameter D_in and the base of the wedge protrusions, the diameter of which is D_in-2z. The diameter at the top of the wedge protrusions D_p is equal to D_p= D_in+2h.

EFFECT: accuracy of the inner corrugated surface of the cylindrical shell is increased by eliminating sags on it.

1 cl, 2 dwg