AP1000核电厂主泵法兰螺栓在役检查系统开发

Development of In-Service Inspection System for Flange Bolts of Reactor Coolant Pump in AP1000 Nuclear Power Plant

AP1000核电厂反应堆主泵法兰螺栓是在役检查重要监督项目之一,目前国内尚无针对该部件的在役检查系统及应用案例。本文结合AP1000主泵法兰螺栓结构特点、现场高剂量环境及复杂检查条件分析,设计开发了一套从螺栓中心孔内壁实施超声检测、适用于在役检查要求的主泵法兰螺栓在役超声检查系统。主泵模拟体上的调试试验结果表明,该系统可实现周向运行、垂直方向避障、专用超声探头与螺栓孔精确对中调节等功能,进而实现对主泵法兰螺栓的超声扫查。工程应用结果证明本系统满足AP1000核电厂主泵法兰螺栓在役检查现场要求,具有较高的可靠性和良好的适用性。

The flange bolts in-service inspection of reactor coolant pump in AP1000 Nuclear Power Plant is one of important supervision items.At present,there is no in-service inspection system and application case in China for this component.Combined with the structural characteristics of AP1000 reactor coolant pump flange bolts,the analysis of on-site high-dose environment and complex inspection conditions,this paper designs and develops a set of in-service ultrasonic inspection system for reactor coolant pump flange bolts,which implements ultrasonic inspection from the inner wall of the bolt center hole and is suitable for in-service inspection requirements.The debugging and test results on the simulation body of the reactor coolant pump show that the system can realize the functions of circumferential operation,vertical obstacle avoidance,precise alignment adjustment between the special ultrasonic probe and the bolt hole,etc.,and then realize the ultrasonic scanning of the reactor coolant pump flange bolts.The engineering application results show that the system meets the requirements of in-service inspection of flange bolts of reactor coolant pump in AP1000 Nuclear Power Plant,and has high reliability and good applicability.