METHOD FOR MANUFACTURING GRID OF RIFFLES ON INNER SURFACE OF CYLINDRICAL SHELL Russian patent published in 2021 - IPC B21K21/06 B21D17/02 B21C37/20 

FIELD: mechanical engineering.

SUBSTANCE: invention relates to the production of cylindrical shells, on the inner surface of which a diamond-shaped grid of riffles is applied. The method for manufacturing a grid of riffles on the inner surface of a cylindrical shell consists in installing a cylindrical shell into a distribution device, forming it in two consecutive operations with a tool rod having a working mandrel with spiral wedge protrusions with a lifting angle of no more than 45° in the first operation and in the second operation with an opposite lifting angle of no more than -45°, and obtaining a part with a diamond-shaped riffle grid on the inner surface of the cylindrical shell, followed by removal. The forming of the cylindrical shell in the first operation is carried out simultaneously with a distribution coefficient of 1.05…1.2 and corrugation by spiral wedge projections with a height of (0.005…0.025)D_db0 located on the surface of the working mandrel, while the cylindrical shell or tool rod with the working mandrel is rotated around the axis and a semi-finished product with a diameter of D_db1=(1.05…1.2)D_db0 is obtained, and in the second operation, the semi-finished product is distributed with a coefficient of 1.05…1.2 and grooved with a tool rod with a working mandrel with a diameter D_sf1=(1.05…1.2)D_sf0 and spiral wedge protrusions with an opposite lifting angle of no more than -45°.

EFFECT: expansion of the technological capabilities by reducing the technological force of applying riffles.

1 cl, 2 dwg