Normal vibrations are acceptable in any component that is under the action of any continuous impact. But when these vibrations start to grow and reach an undesirable level, they cause permanent failure and, consequently, significant damage to the system.
A steam turbine’s functionality is affected highly due to the presence of vibrations in it. Structurally a steam turbine is a complex assembly compounding many delicate components. Any sort of uncontrolled vibration due to a component can cause system failure and, consequently, a significant disaster. Thus, the analysis of vibrations’ cause and intensity is essential to ensure proper operations and safety.
The possible reasons for vibrations are the unbalanced rotor and rotor parts, faulty or no stress analysis of steam piping, deposition on steam turbine blades, damage of journal bearings, actuator and governor fluctuations, improper lubrication, uneven cooling and warming of steam turbine, improper axial and radial clearance, etc.
The effects of high vibrations in the Steam Turbine machine are not only degrading the machine’s operation by increasing the risk for normal operation and shortening the machine’s life but also for operational and maintenance personnel.
Timely maintenance of steam turbines with preventive and predictive maintenance schedules, standard installation and commissioning practices, and replacement of damaged parts can avoid vibrations in steam turbines.