Electricite De France

Societe Anonyme

Intercontrole S.a.

Electricite De France Service

Pierre Vidal

Robert Saglio

Jean Bezier

Guy Zacharie

Gilbert Vigneron

Thong Nguyen-Thanh

Philippe Druelle

Lucien Guillemin

Jean-Louis Tocci

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

Detensioning of expanded tubes is brought by way of an installation using a rotopeening method. The tool is constituted by a cage moved along a helical path centered on the axis of the tube to be treated. The cage supports in rotary manner a shaft, whose axis is parallel and offcentered with respect to that of the cage. The shaft carries flexible plates, called brushes, whose ends are equipped with shot able to peen the inner wall of the tube during the rotation of the shaft. The helical path ensures a regular distribution of the impacts and consequently a uniform treatment of the surface.

Installation for the detensioning of expanded tubes, particularly in a

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Montigny-Sur-Loing, France

Pierre Vidal