METHOD FOR FASTENING TUBES IN TUBE PLATE Russian patent published in 1998 - IPC

FIELD: plastic metal working, namely, fastening tubes in tube plates of heat exchangers due to localized oriented plastic deformation of tube material. SUBSTANCE: tubes are fastened in tube plates by forming annular trapezoidal cross section extensions on outer surface of tube ends, placing tube in plate apertures with annular rectangular cross-section recesses, matching extensions and recesses, fixing tube against possible displacement and then fastening it by applying compression effort at side of inner surface of tube. One of extensions has diameter more than that of tube plate aperture. Tube is fixed against possible axial displacement by elastically pressing-in said large-diameter annular extension in aperture of tube plate and releasing extension at matching it and annular recess. EFFECT: enhanced efficiency. 4 dwg