CPR1000核电厂主管道90°弯头结构优化研究

Research on 90° Elbow Structure Optimization for Main Coolant Piping of CPR1000 Nuclear Power Plant

研究CPR1000核电厂主管道90°弯头壁厚的分布规律,提出一种优化的90°弯头结构。优化后的弯头结构与原设计结构的主要差异为:原设计弯头在内弯处120°范围内向管道内部凸起局部增厚,120°到中性面为厚度过渡区,外弯180°范围没有增厚;优化后的结构利用内外圆偏心实现弯头外弯处壁厚薄而内弯处壁厚,弯头截面内径为一个完整圆形,整体壁厚均匀变化。分析结果表明,改进后的结构满足规范要求,更有利于加工制造。。

For main coolant piping 90~° elbow of CPR1000 nuclear power station, the theoretical thickness distribution was researched, and an optimized elbow structure was designed. The main difference between the optimized elbow and present design elbow is as follows： for the present design 90° elbow, the 120° of internal rounding area are thickened, then transitioned to the mid surface, while the external rounding area keeps normal thickness; for the optimized structure, based on the departure of internal and external circle center of elbow section, wall thickness is designed with regularly changing from higher thickness in the internal rounding area to less thickness in the external rounding area, and keep the internal section a regular circle.This optimized elbow structure can realize mechanization, and improve efficiency and machining precision.