METHOD FOR FORMING HOLLOW PARTS OF FLAT SHEET BLANKS AND APPARATUS FOR PERFORMING THE SAME Russian patent published in 2004 - IPC

FIELD: plastic working of metals, possibly manufacture of hollow parts, mainly spherical, toroidal and others.

SUBSTANCE: method for forming hollow parts of flat sheet blanks setting constant total thickness of pack in direction of force action upon it; making shaping surfaces on pressure members; at forming spherical, toroidal parts and tore-halves setting thickness value of flat sheet blank and its diameter equal to that of container according to predetermined relations; then realizing first stage of forming procedure by upsetting pack of shaping members with blank and transforming blank in case of hemisphere - into cone semifinished product, in case of tore half - to semifinished product with annular cone cavity having predetermined conicity degree; then removing lower shaping member and pressure member and placing instead of the last spherical or toroidal die with cone inlet edges; drawing respective semifinished product to hemisphere or to tore half by applying pressure at side of upper shaping member. Die of apparatus for forming hollow parts of sheet blanks has inlet cone whose conicity angle is set according to given formula.

EFFECT: improved quality of parts due to elimination of thickness difference.

3 cl, 21 dwg, 1 ex