METHOD OF FIXING HEAT EXCHANGE TUBES IN TUBE PLATES Russian patent published in 2013 - IPC B21D39/06 B21D53/08 F28F9/16 

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and may be used in fixing tubes in tube plates of heat exchangers. Shaped flange with annular bulge and grooved sections are made on tube. Said flange is fitted in tube bore that has major and auxiliary annular grooves. Said flange is strained by mechanical rolling rolls to allow its free expansion. Said flange is pre-secured in tube bore. Then, said flange is finally secured. Note here that structural element is formed in said major annular groove and barrier protection in said auxiliary annular groove. Said structural element is used to set performances of the joint, that is, strength and density, maintained by displacing flange outer and inner grooved sections relative to said structural element.

EFFECT: antirust protection of tube-to-tube plate joint wherein no turbulent flows are possible.

2 cl, 14 dwg, 1 ex