多瓦预载荷调整对核主泵轴系临界特性的影响

Influence of Multi-Pads Preload Adjustment on Critical Properties of Nuclear Main Pump Shafting

针对高可靠性立式轴系的横向振动问题,以四瓦水润滑导轴承为研究对象,以多瓦预载荷调整为出发点,分析预载荷系数对导轴承静动特性的影响,同时采用模态分析方法计算2种典型瞬态工况下核主泵轴系的一阶弯曲临界转速及模态振型。结果表明:随着预载荷系数的增大,叶轮和下飞轮处的弯曲程度减小,轴系的临界转速升高;当预载荷系数超过0. 4时,临界转速急剧增大,范围迅速减小。

Aiming at lateral vibration in a high reliability vertical shafting,the multi-pads preload adjustment as starting point,a d the influence of preload factor on static and dynamic characteristics of four-pad water lubricated guide bearings is analyzed.The critical speed and mode shape of first-order bending vibration of nuclear main pump shafting under two typical transient operating conditions are calculated by using modal analysis method.The results show that the bending degree of impeller and lower flywheel reduces and the critical speed of increase of preload factor.The critical speed increases sharply and the range decreases rapidly when the preload factor above 0.4.