核电厂上充泵汽蚀诊断及整治研究  

Diagnose and Treatment of Charging Pump Cavitation in Nuclear Power Stations

作　　者：杨璋[1,2] 王合旭 蒋彦龙[1] 孙程斌 

机构地区：[1]南京航空航天大学航空宇航学院,南京210016 [2]福建宁德核电有限公司,福建宁德355200

出　　处：《核动力工程》2016年第4期77-80,共4页Nuclear Power Engineering

摘　　要：研究压水堆核电厂卧式12级单吸中开筒袋式离心上充泵(RHM100-205.12)汽蚀的典型振动特征、产生原因及解决方案。上充泵上充工况运行时存在异常振动波动且波动幅度超过国标规定的报警值。监测发现上充泵的振动时域信号中存在明显瞬间冲击,频域信号中存在叶片通过频率等谐波分量与宽带噪声,诊断首级叶轮处产生汽蚀,大修解体检查确认首级导叶顶部叶片前缘处被汽蚀严重破坏。上充泵汽蚀的产生,主要原因是汽蚀安全余量k值偏小。现场试验表明改变首级导叶叶片前缘与叶轮叶片尾缘间径向间隙能极大影响汽蚀程度,可用于提高k值。将间隙扩大1 mm后,汽蚀破坏显著改善。研究表明:监测RHM型上充泵入口侧垂直方向振动测点的典型振动特征可简易诊断汽蚀故障;扩大首级导叶叶片与叶轮叶片间径向间隙能有效缓解汽蚀。The typical vibration characteristics, cause and solutions of the cavitation problem of the horizontal-12stages-single suction-bag type-centrifugal charging pump （RHM100-205.12） has been analyzed. There were abnormal vibration fluctuation and fluctuation value beyond the alarm limitation phenomenon when charging pump runs on in-charge condition. It was found that there was typical vibratory shock signal in time domain; broadband noise, blade passing frequency and harmonic component and so on in frequency domain especially by charging pump＇s entrance side in vertical direction. It was diagnosed that cavitation corrosion fault happened near the first vane wheel, which was approved by strip inspection during overhaul. The lower cavitation safety margin k of charging pump RHM was the main cavitation cause, which should be increased in order to avoid the cavitation corrosion fault. It has proved that the charging pump＇s cavitation can be influenced by changing the cap between first impeller and vane by experiment study infield. The cavitation has been improved effectively through expanding the cap by 1 mm. Also it has proved that the cavitation of the charging pump RHM can be diagnosed simply by monitoring its vibration characteristics near the pump entrance side in the vertical direction and the cavitation can be improved effectively through expanding the cap.

关 键 词：上充泵 汽蚀 振动 频谱 

分 类 号：TH311[机械工程—机械制造及自动化]