核电厂发电机定子冷却水泵振动超标分析及改造技术

Analysis of Vibration of Cooling Water Pump for Generator Stator in Nuclear Power Plant and Improvment on Its Technique

某核电厂机组运行期间,部分发电机定子冷却水泵多次出现振动偏高,超出运行标准,现场处理合格后运转一段时间会再次复现。针对这一问题,采用现场排查与振动频谱分析相结合的方法,对冷却泵的振动问题进行系统分析,发现电机振动多次超标的主要原因是泵组整体框架基础刚性薄弱,变形后导致机组安装平面变化所致,另外泵安装和运行中产生应力不均,经一段时间运行后导致结构变形,故出现调整合格一段时间后又超标。针对此问题提出了基础焊接加固改造结合基础虚角优化方法,成功解决了该类泵组振动频繁超标问题。

The vibration of some cooling water pumps for the generator stator occurs for times during the operation of nuclear power plant units,it is over the operating standard.After the on-site treatment,the operation is smooth for a time,and then the vibration occurs again.Aiming at this problem,this paper uses a combination of on-site investigation and vibration spectrum analysis to systematically analyze the cause of the cooling pump vibration.It is found that rigidity is a lack in the foundation of the pump frame,thus causing the motor vibration.As a result,the uneven stress of other pumps occurs during installation and operation,it results in the structural deformation after re-operation,and it operats normally for a time and then it exceeds the standard.Aiming at this problem,this paper proposes a method of basic welding reinforcement and basic imaginary angle optimization,which is used to solve the problem that the vibration exceeds the constant.