摘要
某台汽轮机低压叶片发生断裂,通过对叶片常规强度、动频、有限元强度的计算及有限元动响应的分析,结果表明:叶片断口位置均位于与轴向一阶及扭振一阶共振时所产生的最大动应力区域,在500～620Hz频率范围内的汽流激振是叶片低周疲劳断裂的根本原因。对此,提出了提高叶片材料抗腐蚀性能,采用自带冠成圈结构叶片,避免低负荷低真空运行等防治措施。
Through the conventional strength calculation of blade, the vibration frequency calculation, the finite element strength calculation,and finite element dynamic response analysis etc. , the analysed results of low- pressure blade rupture of steam turbine in one power plant show that the locations of blade fractures all are in the maximum dynamic stress zones resulted from resonance of axial first order vibration and torsional vibration. The fatigue fracture of blade mainly caused by steam flow excited vi- bration with frequency of 500-620 Hz,for this,the preventive measures,such as enhancing the corro- sion resistant ability of blade material, adopting blade structure with crown - shaped ring, as well as low load low vacuum operation etc. ,have been put forward.
出处
《热力发电》
CAS
北大核心
2012年第5期99-101,共3页
Thermal Power Generation
关键词
汽轮机
叶片
汽流激振
疲劳断裂
有限元
steam turbine
blade
steam flow excited vibration
fatigue rupture
finite element
