某核电厂主给水调节阀在满功率运行时开度持续增大问题研究

Study on the Increased Opening of Main Feedwater Control Valve Increasing during Full Power Operation in a Nuclear Power Plant

某核电厂机组在满功率稳定运行期间,主给水调节阀的开度持续增大,如果该趋势不能控制,机组存在降功率或更严重的风险。经故障分析及现场解体检查,最终确定主给水调节阀的开度持续增大是由于阀笼堵塞导致。本文通过结合该阀阀笼特点,分析出导致阀笼堵塞的原因,根据现场实际制定出处理方法,为主给水调节阀的调试和运行以及给水系统的异物控制给出建议。

During full power operation in a nuclear power plant,the opening of the main feedwater control vlave keeps increasing.It will bring reducing power or more serious risks to the nuclear power plant if the increasing trend cannot be controlled.After fault analysis and site disassembly inspection,it is valve cage blockage which cause the opening of feed-water control valve keeps increasing.The reasons which cause the valve cage blockage have been discovered and the corresponding treating methods have also been established by combining the characteristics of the valve cage and field practice.In addition,some suggestions for the startup and operation of feed-water control valve as well as foreign matter control for water supply system are provided.