**ABSTRACT**

The present study focuses on elucidating the fundamental reasons underlying the emergence of vibrations in steam turbines. During operation, vibrations are observed not only in the components of the machinery that undergo cyclical motion but also in those components connected to the equipment. Therefore, vibration monitoring holds great importance in identifying malfunctions in the functional operations of turbomachinery, enabling timely detection and prevention of potential accidents. Using the steam turbine unit as an example, it is noteworthy that the rotor primarily undergoes oscillatory motion, where it is essential to recognize that vibrations also manifest in bearings, housings, turbine foundations, pipelines and surrounding components. The thorough examination of vibration should encompass not only turbine rotors but also the entire turbine assembly, including the generator and all associated equipment. It is essential to conduct a comprehensive evaluation of the overall system to ensure optimal functionality. Academic research papers typically do not often assess the specific number of working hours and conditions which are leading to rotor damage, also in that sense, not determining if damage is a result of wear and tear during prolonged undesired operation. Instead, the emphasis is commonly placed on analyzing elevated levels of vibrations and investigating the associated occurrence of cracks. This paper aims to provide a comprehensive summary of the main causes of vibrations through a unified perspective on the various conclusions available, regarding the diverse causes behind these common and complex vibration occurrences.

**KEYWORDS**

PAPER SUBMITTED: 2024-01-05

PAPER REVISED: 2024-02-09

PAPER ACCEPTED: 2024-02-12

PUBLISHED ONLINE: 2024-04-14

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