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

FIELD: plastic metal working, possibly combination type securing of tubes to tube plates by mechanical rolling-in and welding. SUBSTANCE: method comprises steps of profiling end portion of tube subjected to preparing operations and forming thickened end portion; making in opening of tube plate at side of its front surface annular recess with bottom surface inclined relative to tube axis; placing tube into tube opening in such a way that tube end is arranged over front surface of tube plate; expanding thickened portion of tube along length exceeding depth of annular recess and performing combined deforming of tube and tube plate at applying axial effort to end of tube; providing lengthwise shift of thickened portion relative to bottom surface of annular recess; then fixing tube relative to walls of opening of tube plate by welding. EFFECT: target operational characteristics of tube-to-tube plate joints realized without acting upon welded seam, elimination of damage of welded seam. 4 dwg