Research On The Main Manufacture Technology For Nuclear Power Steam Generator Tube To Tube-sheet

Tube-to-tubesheet welding and expanding technology is one of the key steam generator manufacturing technologies, and it is the key path of steam generator manufacturing.Welded-and-expanded tube-to-tubesheet joints are important pressure boundary to shield radioactivity of reactor. Under high temperature and pressure working conditions, we must ensure the welded-and-expanded tube-to-tubesheet joints are leak-free, the manufacturing quality of the joints directly influences the normal operation of steam generator. The operating experience of nuclear power station indicates that, welded-and-expanded tube-to-tubesheet joints are accident-prone areas of steam generator or primary circuit, the quality of the joints directly influences the safe operation of the nuclear power station. The practice experience of manufacturers also indicates, the quality control of welded-and-expanded tube-to-tubesheet joints is the weakest link in the whole equipment quality control, and it is necessary to research tube-to-tubesheet welding and expanding manufacturing technologies.The research takes welded-and-expanded tube-to-tubesheet joints of steam generator as analysis object, firstly, uses the finite element method to analysis and simulate expanding process, analyzes the factors that influence expanding quality, and researches by the expanding experiments. Secondly, simulates product welding and welding experiments, and works out welding procedure specification and welding operation requirements which meet the quality demands of the product. Through the theoretical analysis and experimental verification, we can get change rule and process parameters, to provide theoretical basis and experimental data for main manufacture technology of steam generator tube-to-tubesheet——programming expanding and welding process.