Mechanical Vibrations of Turbine-Generator Bearing Malfunctions in Hydroelectric Power Plants and Solution Methods

Year 2025, Volume: 11 Issue: 2, 421 - 428, 29.12.2025

Gökhan Kahraman

https://doi.org/10.29132/ijpas.1681193

Abstract

The fact that the power and dimensions of hydraulic turbines manufactured today have increased significantly also brings about a serious mechanical vibration and shaft oscillation problem. It is known that a machine exposed to mechanical vibration (vi-bration event) is constantly strained by variable mechanical stresses such as pulling, pressing, bending, twisting, and shearing. The exposure of hydraulic turbines to such vibrations and oscillations significantly reduces operational safety and operating time. In this study, mechanical vibration (vibration event) and shaft oscillation failures that occurred as a result of the bearing clearance exceeding the permitted limits in a Francis type turbine belonging to a hydroelectric power plant were investigated. The shaft os-cillations that occurred after the turbine-generator bearings were re-adjusted were compared with the shaft oscillations that occurred in the event of a failure. As a result, after the dimensions of the hydraulic turbine bearings were brought to the accepted standards after the failure, mechanical vibrations and shaft oscillations returned to normal levels. Failures caused by mechanical vibration and major failures such as bearing friction that would occur as a result of excessive shaft oscillations were prevented.

Keywords

mechanical vibration; , shaft oscillation; , hydroelectric

Hidroelektrik Santrallerde Türbin-Jeneratör Yatak Arızaları Sonucu Oluşan Mekanik Titreşimler ve Çözüm Yöntemleri

Abstract

Günümüzde imal edilmekte olan hidrolik türbinlerin güçlerinin ve boyutlarının çok artmış olması ciddi bir mekanik titreşim ve şaft salınımı problemini de beraberinde getirmektedir. Bilinmektedir ki mekanik titreşime (vibrasyon olayı) maruz kalan bir makine devamlı olarak çekme, basma, eğme, burma, kesme gibi değişken mekanik baskılarla sürekli olarak zorlanmaktadır. Hidrolik türbinlerin bu tür titreşim ve salınımlara maruz kalmaları işletme güvenliğini ve işletmede kalma süresini önemli derecede azaltmaktadır. Bu çalışmada, bir hidroelektrik santrale ait Francis tipi tür-binde yatak boşluğunun müsaade edilen sınırları aşması neticesinde meydana gelen, mekanik titreşimler (vibrasyon olayı) ve şaft salınımları arızası incelenmiştir. Tür-bin – Jeneratör yataklarına tekrar ayar yapıldıktan sonra oluşan şaft salınımları, arıza durumunda oluşan şaft salınımları ile kıyaslanmıştır. Sonuç olarak arıza sonrası hidrolik türbin yataklarının ölçüleri kabul edilen standartlara getirildikten sonra mekanik titreşimler ve şaft salınımları normal seviyelere gelmiştir. Mekanik ti-tre-şimden kaynaklı arızalar ve aşırı şaft salınımı sonucu oluşacak yatak sürtmesi gibi büyük arızalar engellenmiştir.

Keywords

mekanik titreşim; , şaft salınımı; , hidroelektrik

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