重水堆核电厂循环冷却水旁路管线出口隔离阀振动分析及处理

Vibration Analysis and Treatment of Isolation Valve of Circulating Cooling Water Pipeline in Heavy Water Reactor Nuclear Power Plants

某核电站循环冷却水旁路压力控制管线出口隔离阀阀杆往复运动明显,长期振动导致该阀门手动执行机构定位销多次断裂。通过勘查、测量及一维水力和三维流场分析,最终确定管线布置不合理导致流体通过上游进口隔离阀和中间调节阀后,产生的紊流不断冲击下游出口隔离阀阀板,引发阀杆往复运动导致手动执行机构定位销断裂。针对根本原因提出了解决方案,即取消该蝶阀装置改由管道法兰直接相连,并经可行性评估及技术改造,确认振动问题已消除。

The valve stem of a nuclear power plant circulating cooling water bypass pressure control pipeline outlet isolation valve has obvious reciprocating movement,and long-term vibration caused the positioning pin of the valve manual actuator to break several times.Through the investigation,measurement and one-dimensional hydraulic and three-dimensional flow field analysis,it is finally determined that the unreasonable pipeline layout leads to the turbulence generated after the fluid passes through the upstream inlet isolation valve and the intermediate control valve,which constantly impacts the downstream outlet isolation valve plate,causing the reciprocating movement of the valve stem,resulting in the fracture of the positioning pin of the manual actuator.According to the root cause,the solution is put forward,that is to cancel the butterfly valve device and connect directly with pipe flange.After feasibility evaluation and technical transformation,it is confirmed that the vibration problem has been eliminated.