Use of fracture mechanics to evaluate the bearing capacity and remaining life of rotors in turbomachinery

Improvement of the Mechanical Characteristics, Hydrogen Crack Resistance and Durability of Turbine Rotor Steels Welded Joints

“…There are precipitates of the cementite type The calculated and experimental data characterizing the regions of the formation of the corresponding structures were compared with the data of the thermos-kinetic diagram of the steels 25H2NMFA and 20H3NMFA. The comparison, as well as taking into account the known results [22][23][24][25][26][27][28][29][30][31], made it possible to improve the mathematical model of welding heating of the manufactured rotor and to refine the numerical data characterizing the thermal cycle.…”

“…The operating time of most of the NPP power units has already exceeded its park resource [25][26][27][28][29][30][31][32][33][34]. Thus, the priority direction of research is to increase the reliability and extend the service life of the operation of power units, including the components of power units.…”

“…The increase in operational requirements for the rotors of high-power steam turbines at nuclear power plants necessitates improving the quality characteristics of the initial metal structure of their welded joints, which is characterized by the presence of a certain heterogeneity. It is advisable, by using the optimal welding heating of the manufactured joints, to reduce the level of the initial structural heterogeneity, which increases with an increase in their operating time [25][26][27][28][29][30][31][32][33][34].…”

“…The operation of many structures-particularly, steam and hydrogen turbine rotors, cooling infrastructures of powerful semiconductor devices and industrial singlecrystal growth applications [3][4][5][6][7][8][9][25][26][27][28][29][30][31][32][33][34]45,[55][56][57][58][59][79][80][81][82][83][84][85][86][87][88][89][90][91]110]-is accompanied by their cyclic loads, which often exceed the yield strength of the material [52,[54][55][56], based on understanding the hydrogen embrittlement of materials from the atomistic level to the continuum [100][101][102][103][123][124][125]…”

“…1-rotor shaft; 2-current supply slot; 3-ventilation slot; 4-slot wedges; 5-current supply tire; 6-shaft fracture areas due to fretting (wedge joining areas) (e). Design slot wedges rotor tail after application of the antifretting measures system: 1-rotor shaft; 2-current supply slot; 3-ventilation slot; 4-current supply wedge; 5-current supply tire; 6-ventilation slot wedge; 7-easy shifting seal (f) [2,6,[23][24][25][26][27][28][29][30][31][32][33][34].…”