火电厂凝结水泵停泵水锤分析

Water Hammer Analysis of Condensate Pump Stopped in Coal-Fired Power Stations

火电厂凝结水泵在发生事故停泵时,伴随不科学的关阀规律,将会出现严重的水锤现象。贵州某600MW超临界火电厂投运以来,在凝结水泵停运时多次发生持续时间短暂的振动高报警现象。停运瞬间止回阀处伴随有很大的声响,严重时导致正在运行的冷凝泵振动高保护跳泵,对电站安全稳定的运行造成巨大的隐患。为解决上述问题,根据其凝结水系统运行情况,建立系统仿真模型;通过进行瞬态仿真可知,旋启式止回阀的快速关闭是导致水锤压力过大的主要原因;更换安装新型液控止回阀、选择科学合理的两阶段关阀规律并根据系统运行特点在阀后设置气压式调压室,能够有效地降低阀后最大水锤压力和水锤波动性。压力水系统中液控止回阀和配置气压式调压室是防护水锤事故的有效的措施。

It will appear serious water hammer phenomenon when the pump in Coal-fired power plant condensate systems is stopped in an accident with no scientific valve close disciplines. Since one supercritieal 600 mw coal-fired power plant in Gui Zhou province was put intooperation , many high vibration warning phenomena with short duration happened when the condensate pump was shut down, There will appear very large noise on the valve position at the moment of stopping, causing the condensate pump jump down due to high vibration when it is too serious, which bringing about huge risks to the stable operation of Coal-Fired Power Plant. To solve the problems stated above, this paper builds up System Simulation Model according to the system operation conditions of condensation water in the pump. Through transient simulation we can conclude that the rapid close of the Swing-Type valve is the key reason causing overpressure on the water hammer. Changing to install new hydraulic control valve, choosing scientific and reasonable two-step close discipline and setting air injection surge chamber according to the characteristic of system operation all can effectively reduce the maximum pressure and volatility of water hummer after closing the valve Instal- ling hydraulic control valve and deploying air injection surge chamber in the pressure water system are effective meth- ods preventing water hummer accidents.