METHOD FOR SECURING TUBES TO TUBE PLATES Russian patent published in 2003 - IPC

FIELD: plastic metal working, possibly securing tubes to tube plates of heat exchange apparatuses at using effect for locallized directed plastic deformation of tube material. SUBSTANCE: method comprises steps of forming calibrated portion of tube end due to expanding it by means of rigid punch until diameter exceeding that of tube opening of tube plate; profiling calibrated portion by radial swaging; initially applying deforming effort on area adjacent tube end; then distributing effort on the whole surface of formed end portion in such a way that to make outer diameter of end portion equal to size providing minimum gap between tube opening and end portion; placing end portion of tube into opening of tube plate; fixing it against possible motion and fastening due to applying compression effort to inner surface of tube. EFFECT: enlarged manufacturing possibilities of method due to fastening tubes with different size of cross section without significant increase of technological effort. 8 dwg