D. N. Dewangan, Manoj Kumar Jha, Y. P. Banjare
The fault mode of steam-induced vibration, unbalance of rotating elements, misalignment of turbine shaft, rotor malfunction, oil film instability of bearing etc. are accountable for unreliable and uncertain failure of power plant. Experience of operators, maintenance policy execution of maintenance team and using standards codes of good practices by designers and manufacturers are reducing the potential failure modes of the system. The work investigate the reliability of steam turbines installed in a thermal power plant. Reliability estimation is based on a last five year historical failure database of two turbines of 500 MW, both are installed and commissioned at the same time. The method of reliability evaluation is based on concepts of system reliability, such as functional tree development, application of failure mode and effects analysis (FMEA) to categorize critical components based on a historical failure database to improve the system reliability. It is necessary to improve the reliability indices of the power plane by taking some measures such as well planned and routine maintenance of equipments as well as training and retraining of technical human resources of the major equipment.