Electricite De France

Electricite De France - Service National

Societe Anonyme

Guy Zacharie

Jean Bezier

Pierre Vidal

Gilbert Vigneron

Pierre S Paul

Daniele Guttmann

Thong Nguyen-Thanh

Lucien Guillemin

Yves Rouillon

Georges Le Huede

Jean R Donati

To repair a corroded region of the end of a heat exchanger tube, a sleeve is inserted, then expanded into the tube both in the area of the tube sheet and beyond the corroded area, then local welds are made in each of the expanded regions. Thereafter, the end of the sleeve is expanded against the tube in a region inside the tube sheet and above the local weld.

Method of repairing or protecting an end of a metal tube in a heat

A structural part for use in high temperature aqueous medium consists of an austenitic nickel-chromium-iron alloy containing by wt. 5 to 10% of iron, 18 to 20% of chromium and more than 60% of nickel. All components of the alloy, but chromium, may be in the standard ranges of well-known and proven alloys, typically 600 and X750 alloy.

Structural parts of austenitic nickel-chromium-iron alloy

A tube which has been expanded in a support such as the tube-sheet of a heat exchanger is subjected to diametral deformation of controlled intensity and direction in the transition zone between the expanded portion of the tube and the portion which has a nominal diameter by means of an axially displaceable and radially expandable tool having a bullet-nosed shape or by means of a tube-expander of the type comprising a mandrel fitted with rollers or by means of a fluid under pressure.

Method for mechanical removal of tensile stresses in a tube which has

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Fontainebleau, France

Guy Zacharie