控制棒驱动机构下部Canopy焊缝封堵组件设计与分析

在某些因素的影响下,少量压水堆核电站控制棒驱动机构(CRDM)下部Canopy焊缝区域会发生破损泄漏。通过在焊缝外部安装封堵组件,能有效预防、封堵和遏制破损焊缝的进一步泄漏。本文针对该组件的结构特点,分析关键零件的受力情况,利用有限元软件验证该组件的封堵效果。结果表明,该组件能有效降低焊缝区域的应力水平。同时,通过对比分析预紧力、配合面角度和摩擦系数等因素对焊缝应力水平的影响趋势,得出了各因素的影响关系曲线和最佳参数。所分析数据可应用于结构设计、加工制造和装配工艺,使该组件达到最佳的封堵效果。

Design and Analysis of Control Rod Drive Mechanism Lower Canopy Welding Plugging Assembly

Control rod drive mechanism (CRDM) lower Canopy welding zone could leak under the influence of certain factors in some pressurized water reactors. The plugging assembly mounted on the welding externally can prevent and seal the leakage. According to the structure characteristics of the components, the stress conditions of key components were analyzed and the plugging effect of the assembly was verified by using the finite element software. The results show that the component can effectively reduce the stress of welding zone. At the same time, the stress level trends due to different pre-tightening forces, contact surface angle and friction were analyzed, so that the relationship curves and the optimum parameters were educed. The analysis data can be applied to the structure design, manufacture and assembly process, for making the component to achieve the best effect of plugging.