TUBE TO TUBE WALLS SECURING METHOD Russian patent published in 2007 - IPC B21D39/06 B21D53/08 

FIELD: plastic working of metals, possibly tube securing to tube walls of heat exchange apparatuses by means of directed plastic deforming of tube material.

SUBSTANCE: method comprises steps of placing tube in tube wall opening with annular recess at providing protrusion of tube end over front surface of tube wall; fixing tube against axial motion due to placing on part of its protruded end locking ring with threaded holes for screwing-in bolts and for forming local bulged portions on tube; profiling protruded end of tube; shaping annular thickened portion on tube arranged in annular recess of tube wall and shaping annular protrusion on front side of tube wall. After securing profiled end of tube circular welding of tube to tube wall is realized. Then tube is broached for expanding it in range of tube wall thickness value in zone of bulged portions and for creating plastic yielding of tube material relative to edge of opening at back side of tube wall.

EFFECT: improved quality of non-detachable tube-to-tube wall joint.

2 cl, 9 dwg