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The vibrations of a double-seat weighty rotor of the steam turbine with a breathing transverse crack are examined in the field of operating environment temperatures. The 3D vibration model for the rotor with a breathing transverse crack is applied. The variable two-dimensional temperature field is found from the solution of nonstationary heat transfer problem. Its effect on the contact of crack edges on rotor vibrations was evaluated. The distribution of stress intensity factors along the crack front was established for different rotor positions. Fatigue crack extension modes are assessed. [ABSTRACT FROM AUTHOR]

The authors put forward a procedure of creep analysis for variable loading conditions, which involves the use of the incremental creep theory and finite element method. Variable loading with load increase and relief at a constant temperature is considered as a stepwise process. The authors study a growth of deflections and stress relaxation in a intermediate-cylinder diaphragm of a steam turbine in various loading modes as well as special features of residual stress distribution in fixed blades. [ABSTRACT FROM AUTHOR]

The paper considers torsional vibrations of turbine shaftings under sudden generator rotor loadings, which are caused by two- and three-phase short circuit. The fatigue damageability of shaftings under the most unfavorable loading conditions has been assessed. [ABSTRACT FROM AUTHOR]

The paper considers the irreversible deformation of steam turbine rotors due to the circumferential non-uniformity of the material mechanical properties based on the numerical analysis of their three-dimensional stress-strain state. It is shown that this non-uniformity can be one of the causes for the occurrence and development of progressive creep deflection of high-temperature rotors that have been in long-term operation and also their bending in case of excess of the rated rotational speed. [ABSTRACT FROM AUTHOR]

A procedure for analyzing vibrations in cracked body using three-dimensional model is presented. The process of 'breathing' is described by conditions of contact between the crack faces. Some example calculations are provided. [ABSTRACT FROM AUTHOR]

We present the results of numerical analyses (in the three-dimensional statement) of the kinetics of stressed state and accumulation of dispersed defects in the zone of discharge holes in the rotor disks of a steam turbine in creep for 400,000 h. It is shown that the zones of discharge holes in the disks of the first two stages suffer the action of the highest stresses and the material in these zones is damaged more intensely that near the surface of the axial channel. [ABSTRACT FROM AUTHOR]