SLEEVE TYPE REPAIR OF DEGRADED NUCLEAR STEAM GENERATOR TUBE

摘要

A sealable multimetallic sleeve for a rapid repair of a degraded tube caused by a detrimental chemical attack on the outside surface of the tube within and in a vicinity of a tube sheet in a steam generator, and the method for sealably inserting the sleeve in the degraded tube spanning the region of the degradation. The sleeve includes an inner member with equivalent mechanical properties of the degraded tube and an outer member metallurgically bonded to the inner member and resistive to caustic intergranular chemical attack causing tube degradation. The sleeve has an expanded portion at one end for positioning in the tube within the tube sheet and a multiplicity of grooves in and adjacent to the other end of the sleeve and braze material contained in the grooves.