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

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

SUBSTANCE: method comprises steps of shaping tube end portions for forming cylindrical portions joined through transition cone part; making in opening of tube plate annular triangular cross section groove and also outer annular groove in the form of annular recess for placing sleeve of plastic material at minimum gaps between joined members; placing tube in opening of tube plate while arranging transition cone portion in front of inner annular groove; fixing tube against possible displacement due to axially compressing tube until providing irreversible deformations of its material; then fastening tube at drifting opening of its end portion. During final stage of securing tube by means of expanding it to cone, bell-shaped part is formed at condition of yielding sleeve material in direction opposite relative to direction of applied effort.

EFFECT: enhanced quality of joints of tubes to tube plate.

6 dwg