METHOD FOR SECURING TUBES TO TUBE PLATES Russian patent published in 2004 - IPC

FIELD: plastic metal working, namely securing tubes to tube plates of heat exchange apparatuses at using effect of localized directed plastic deformation of tube material.

SUBSTANCE: method comprises steps of profiling tube ends for forming cylindrical portions joined by means of cone portion; forming annular triangle cross section protrusions on length part of cylindrical portion of less diameter in such a way that apexes of said protrusions are arranged on outer surface of said cylindrical portion; making opening of tube plate with inner annular triangle cross section groove and with outer annular groove in the form of annular recess for placing in it sleeve of plastic material at minimum gaps between joined members; placing tube in opening of tube plate at positioning cone transition portion in front of inner annular groove; fixing tube against its possible motion by axial compression of sleeve for providing flowing of its material relative to edges of annular protrusions; fastening tube by drifting opening of its end portion; at final stage of tube fastening by cone expansion of it, forming bell at condition of flowing of sleeve material in direction opposite relative to that of applied effort.

EFFECT: enhanced quality of securing tubes to tube plates.

8 dwg