Abstract: A method for fabricating a steam generator and a steam generator wherein primary coolant tubes are sleeved in and in the vicinity of a tubesheet. A smooth transition region is formed between stock primary coolant tubes and sleeved portions thereof in such a manner that no sites for accelerated corrosion are formed. In addition, an adequate volume of material is provided in the transition region to withstand thermal and mechanical stresses and chemical attack. The sleeved tube is preferably thermally treated for improved corrosion resistance.

Abstract: An expandable antivibration bar for use in stabilizing the U-bend portion of heat transfer tubes in a pressurized water reactor steam generator comprises two adjustable rods connected together by an arcuate connector. The two adjustable rods preferably comprise two mating rod sections having complementary angular sliding surfaces thereon, with means provided to move the rod sections relative to each other along the sliding surfaces so as to expand the rods from a first mated cross-sectional width to a second larger cross-sectional width. The ends of the rod sections have means for aligning the two rod sections and maintaining them in alignment during expansion.

Abstract: A sludge collection system for a vertically oriented nuclear steam generator is provided with an upwardly open chamber for receiving separated liquid and incoming feedwater that contain sludge particulates. A plurality of sludge collecting containers are positioned within the chamber and include a top rim encompassing an opening leading into the interior of each container. Generally flat perforated covers are positioned over each container such that a gap is formed between the cover and the adjacent top rim. Particulate material in the water entering the container can settle within the container because of relatively stagnant conditions. Sludge agitation and removal means are provided for remotely cleaning the containers. The sludge collection system components are sized to permit retrofitting this system into existing steam generators.

Abstract: A method for fabricating a steam generator and a steam generator wherein primary coolant tubes are sleeved in and in the vicinity of a tubesheet. A smooth transition region is formed between stock primary coolant tubes and sleeved portions thereof in such a manner that no sites for accelerated corrosion are formed. In addition, an adequate volume of material is provided in the transition region to withstand thermal and mechanical stresses and chemical attack. The sleeved tube is preferably thermally treated for improved corrosion resistance.

Abstract: A steam generator is provided which contains a manifold with a plurality of nozzles for breaking up and washing away sludge which has formed on the upper surface of its tube sheet. The manifold is rigidly attached to the upper surface of the tube sheet and remains in place during conventional operation of the steam generator. The portions of the present invention which are contained within the steam generator do not contain any moving parts and, thus, does not require human intervention in close proximity to components of the steam generator which may be possibly radioactive. High velocity streams of water are used to break up and remove sludge from the upper surface of the tube sheet and openings are provided through the wall of the steam generator for removal of the slurry in which the sludge is entrained.