Development Of The Property Database Of Nuclear Power Steels And Life Management System Of Nuclear Steam Generator Pipes

With the increasing of nuclear power in energy industry.the safety of nuclear power equipment in service becomes a hot issue in the energy equipment field. The research on the safety of nuclear power equipment in the total life-cycle. which is from material selection in the design stage to maintenance and life prediction in the operating stage, plays an important role in the long-term operation of equipment and the safety management in nuclear power plants.For nuclear power steels in China, many problems are involved such as the lack of standards, import-dependence and lack of data management and organization, which particularly is reflected in the material selection of nuclear power equipment. Until now, there is no professional material database to provide a technical guidance in material selection and data management of nuclear power equipment. The existing data are out of order and thus leads to the unpractical database. Besides, the previous research on the structure integrity and life prediction of the key components in nuclear power equipment has focused too much on the defect formation mechanism and damage prediction. How to qualitatively analyze the defects, and thus predict the residual life, especially how to apply this analytical method in practice are still unsolved.In the present work, the material properties and the selection standards for nuclear power equipment are first studied. And then, a professional material property database for nuclear power equipment is developed by employing the computer programming and the data of material properties. The developed database can be applied in the material selection and the property data management and query. On the basis of the developed database, the steam generator (SG) in pressurized water reactor (PWR) is selected as an example to develop a method for defect identification based on the eddy current test (ECT) signal. Finally, a quality management system of nuclear power equipment in the total life-cycle was built. It can be used to manage the nuclear power equipment in the whole process of material selection, damage maintenance and life management. This is very critical for the construction and operation of nuclear power plants.The management system was developed by using Visual Basic6.0language, Access2000and SQL Server2000database. The data of steels were stored in SQL Server database, and shown in the interface developed by Visual Basic language. The curve of ECT signal feature and defects size based on the detected data of steam generator pipes in nuclear power plants, is fitted, and then used in the new defect identifying in practice. The data of defects size and pipes plugging of steam generator are stored in Access database, and shown in the interface as well. Then in Matlab, the SG pipes plugging data are applied to establish a BP neural network, which can be used in the life prediction of steam generator in PWR.