五瓦可倾瓦轴承-转子系统临界转速的研究

Study on Critical Rotating Speed of a Five-pad Tilting-pad Bearing-Rotor System

针对CAP1400常规岛给水泵轴承-转子系统模型,设计了五瓦可倾瓦滑动轴承,利用得到的轴承油膜动力特性系数来求解不同支撑工况下的临界转速,并通过给水泵热态联机试验测试轴承的振动特性.结果表明:可倾瓦轴承刚度和阻尼系数随着转速变化而呈现不同的特性;刚性支撑下的临界转速大于弹性支撑下,而"湿态"工况下水膜刚度的增加使得临界转速大于"干态"工况下,并且远大于实际运行转速;试验测得轴承垂直、水平和轴向上振幅与振动速度均满足国家标准要求.

Based on the model of bearing-rotor system for conventional island pump of CAP1400 nuclear power plant,a tilting-pad journal bearing was designed,of which the critical rotating speed was calculated with dynamic parameters of the bearing oil film under different support conditions,while its vibration characteristics studied through hot-state online test for the feed pump.Results show that both the stiffness and damping coefficient of the tilting-pad bearing change with the rotating speed;the critical rotating speed under rigid supporting is greater than under elastic supporting,and the increase of water film stiffness under ' wet' condition makes the critical rotating speed greater than under 'dry' condition,which is far greater than actual rotating speed.All the amplitude and velocity of relevant vertical,horizontal and axial vibration measured in the test meet relevant national standards.