METHOD OF PRODUCING SHELLS FROM BLANKS AND DEVICE TO THIS END Russian patent published in 2016 - IPC B21D26/02 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and may be used for production of shells from sheet blanks by superplastic forming. The die with blind cavity and the die with through cavity are arranged one above the other. The workpiece is secured at every die with geometrical jamming over the edges and heated. Excess gas pressure p₁ is fed into the die cavity to one workpiece to shape it to contact with the other workpiece. Then, excess pressure p₂ is fed in opposite direction to shape both workpieces to full contact with the working surface of female die and the surface of the other workpiece. Then, excess pressure p₂ is released for simultaneous shaping with reversing of both workpieces by excess pressure p₁ to the moment of touch with the working surfaces of dies to get one finished shell and one semi-finished shell. Now, formed shell, semi-finished product and die with through cavity are withdrawn. Note here that the flat sheet is placed on the die with blind cavity while semi-finished product is placed on the die with through cavity for shaping by excess pressure p₁.

EFFECT: higher quality of shells.

2 cl, 7 dwg