The Developing Of Lifetime Management System Of High Temperature Pressured Parts In Ultra Supercritical Unit

With the development of economy and the increase of electricity peak and valley difference in main power grids, China has put a large number of high-capacity and high-parameter units into operation. It is necessary for the high reliability requirements of boiler pressure parts. In this paper, the strength theory is adopted to analyze the stress of pressure parts in ultra supercritical units like start-up separator and high temperature header. Then, the loss life of pressure parts is analyzed based on simplified stress equations and life calculation methods of fatigue and creep. Finally, the life management system is developed which can be applied to different boiler pressure parts.First, the main failure modes of pressure parts are analyzed and the stress analysis of pressure parts is undertaken based on elastic-plastic mechanics. Then, the stress equations are simplified on the premise of accuracy, which can make the life loss calculation of fatigue and creep convenient. Meanwhile, a appropriate method is chosen to compensate important parts according to the stress anlysis result in ANSYS.Second, on the aspect of fatigue calculation, the ASME standard is chosen. The improved rain flow method is used as the on-line stress range notation, and the stress concentration factors resulting from ANSYS analysis are also used. Then, take the start-up separator as an example, the fatigue life loss is calculated under the actual operation condition.Third, to calculate the high temperature creep loss, the basic step of θ-parameter loss prediction method is concluded. Referring to the corresponding parameters of P91, the programs of θ-parameter method are written in C language programming to make on-line calculation available. Then, take the high temperature header as an example, the creep life loss is calculated using θ-parameter method.Finally, the life management system is developed in C#. It has the framework of Microsoft. Net, and chooses SQL Server as database, then the access to database is achieved by Ado.Net. The system has some modules, like device information management module, metal material module, off-line operation state evaluation module, and accident report management module. Some database is also exiting in the system, which are about operation parameters, device parameters, material information, life loss record and accident report. Then, the life management system is built which can be applicable in different power plants, units and devices.