汽轮机座缸式轴承振动影响因素研究  

Influencial factors of vibration of bearings on turbine exhaust cylinder

作　　者：高庆水[1] 刘石[1] 张楚[1] 

机构地区：[1]广东电网公司电力科学研究院,广州510080

出　　处：《振动与冲击》2014年第13期26-30,共5页Journal of Vibration and Shock

摘　　要：大型汽轮机排汽缸轴承通常采用座缸式。将轴承支撑特性用参振质量和支撑刚度表示,油膜特性用八个刚度和阻尼系数表示,建立了考虑支撑刚度影响后的等效分析模型。计算结果表明,座缸式轴承振动受支撑特性影响较大。支撑刚度不仅会影响系统等效刚度,也会对系统等效阻尼产生较大影响。不同支撑刚度下转子-轴承系统所表现出来的绝对轴振、相对轴振和轴承座振动特性不同。支撑刚度较低时,轴振和瓦振之间的相位差较大,根据三者幅值和相位之间的关系可以评估支撑刚度特性,监测座缸式轴承的绝对轴振比相对轴振更有意义。排汽缸轴承振动对转子不平衡很敏感,可以通过精细动平衡减小振动。The mode of bearing on exhaust cylinder is often used in large turbine unit.An equivalent analysis model was set up to consider the influence of support pedestal stiffness.The support system was modeled as a mass-spring structure and the bearing oil film as eight stiffness and damping coefficients.There is great influence of support pedestal stiffness on the vibration of bearing on turbine exhaust cylinder.The relationships among absolute shaft vibration,relative shaft vibration and bearing vibration are different in different support stiffness cases.If the support stiffness is low,the phase difference between shaft vibration and bearing vibration may be large.The support stiffness characteristics can be evaluated from the three kinds of vibration signals.Absolute shaft vibration monitoring is more important for bearing on exhaust cylinder than that of relative shaft vibration.Vibration of bearing on cylinder is sensitive to rotor unbalance. Accurate balance is effective to reduce the vibration of this kind of system.

关 键 词：汽轮机 振动 刚度 转子 轴承 

分 类 号：TH113.1[机械工程—机械设计及理论]