METHOD OF MAKING THIN-WALL ASYMMETRIC BICURVATURE SHELLS WITH FLANGE Russian patent published in 2013 - IPC B21D22/16 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming, particularly, to making thin-wall asymmetric shells with flange to be used in construction and sanitary engineering. Sheet blank is shaped by rotary drawing to sine law in acting by spinning tool on the blank on displacing from smaller diametre to larger one set with gap with respect to mandrel. With spinning tool displaced by 0.5-0.75 of process pass, blank flange edges are levelled by cutter and remained section is subjected to multipass spinning to shape obeying the sine law to make the flange with width of 0.05-0.10 of maximum diametre of shell ogival part and to cut flange section so that asymmetric shape is obtained. Now, asymmetric shell edge sections is welded to ring flange with mate shape.

EFFECT: higher operating performances, lower metal and labour input.

4 cl, 5 dwg