한국윤활학회:학술대회논문집 (Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference)
- 한국윤활학회 1999년도 제30회 추계학술대회
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- Pages.179-183
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- 1999
증기 터빈에서의 고체 마찰에 의한 축 진동 특성
Characteristics of shaft Vibration due to Rubbing in the Steam Turbines
초록
Rubbing occurs when a rotating element comes in contact with a stationary element. In the steam turbines, the rotating element is the rotor while the stationary elements are usually the oil deflectors and packing seals. Rubbing phenomenon may be often obseued on a new or rebuilt machine rather than on a machine that has been operating for several months or years. Rubbing in the turbine has been classified into two modes by the operating conditions: 1) start up or shut down, 2) steady state. At start up or shut down operation, rubbing produces synchronous whirl vibration, which are caused by thermal bow of the shaft due to localized heating on the shaft surface. While subsynchronous whirl vibration is caused by partial rubbing during the steady state operation. In this paper, the two case studies of troubleshooting for excessive vibration caused by rubbing in the actual steam turbines are investigated.