Computer aided lifetime evaluation and its application to turbines design and their operation

The scope and methodology of the tests of technical condition of heat turbine components are discussed. Particular attention is paid to the problem of computer aided evaluation of the durability of turbine casing, rotor and valves. Components operating at high and variable temperatures are considered. Under such conditions, durability is determined by the creep of the material and by low-cycle fatigue. The structure and the basic assumptions for the developed system of computer aided turbine components durability evaluation are presented. As an example of application of the discussed system, selected results of the analysis of the influence of the turbine startup mode on its durability are included. Another example is concerned the evaluation of operation efficiency of thermo-compression bondings in turbines operating under creep conditions.