水电站进水口闸门未正常闭门分析及处理

Analysis and Treatment of an Abnormal Closing Fault of a Water Intake Gate in a Hydropower Station

针对水电站进水口事故闸门动水落门时未在要求时间内正常闭门的问题,通过对比分析不同工况下落门过程曲线,结合现场观察,推断是在电站出现故障引起闸门动水落门过程中,由于闸门、油缸启闭机振动相对较大,液压启闭机有杆腔高压球阀自由转动而关闭所导致。为此加设了液压启闭机有杆腔高压球阀锁定装置,确保球阀不会自由转动;并建议高压球阀应选择全开位置带有锁定装置的型号;优化油管的空间结构和管道支撑结构布置,减小管道振动;对大尺寸的混流式水轮发电机组应进行过渡过程工况的动水落门试验。

An abnormal gate closing fault was observed in a hydropower station,as the emergency gate at the water intake did not close normally in flowing water within the required time.By comparing the gate closing process curves under different working conditions and the on-site inspection,it is concluded that during the gate closing process in flowing water caused by a power station fault,the gate and the oil cylinder hoist are of large vibration,and the high pressure ball valve in the rod chamber of the hydraulic hoist can rotate freely,which result in the abnormal gate closing fault.Thus,a locking device is installed on the high pressure ball valve in the rod chamber of the hydraulic hoist to ensure that the ball valve will not rotate freely.It is also suggested to select the high pressure ball valve type with locking device in its fully open position.The spatial structure of the oil pipes and the layout of the pipeline support structures should be optimized to reduce the pipeline vibration.For large-size mixed flow hydro-turbine generator units,gate closing tests in flowing water under transitional process conditions should be conducted.