METHOD OF MULTILAYER SHELLS PRODUCTION Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: shell is made by screw winding of strip blanks, that have central longitudinal corrugations, and by simultaneous screw seams welding. Number of longitudinal corrugations is one corrugation less, than the number of layers of the shell. The strips are wound with overlapping and every next strip coil is shifted in relation to the previous one by a value, equalled to ( n - 1) / n of the strip width with "n" = number of shell layers. On one side of the strip edges they make edge corrugation, that is welded to the inner side of the central corrugation and on the other side of the edges they make a flange, that is welded to the external side of the central corrugation. An area, that has thickness by one layer exceeding the shell thickness, is formed in a zone, laid between welding seams on the central corrugation. EFFECT: method is used for production of hollow multilayer articles by winding a strip, that has a central corrugation. 3 dwg