Abstract

Nuclear power pipeline ice plug technology, as the main technical method of nuclear power safety maintenance and innovative design, plays a protective role in the long-term safe operation of nuclear power plants. During the ice plug process, pipelines have complex stress states, which can easily lead to problems such as material yielding, cracking, and even damage. In this study, by building an ice plug test platform for nuclear power pipelines, an ice plug test and a numerical analysis of nuclear power pipelines are carried out to explore the stress distribution of nuclear power pipelines during the ice plug process and its impact on the performance of pipeline materials and to analyze the safety of pipelines in the ice plug process. This study shows that the distribution of stress in the pipeline during ice plug is related to the temperature change and cooling rate of the pipe wall. The stress distribution in different parts is uneven, and the maximum stress appears near the edge of the jacket. According to the temperature data of the pipe wall, the stress distribution of the pipe wall can be obtained by the finite element method. From the test and finite element results, it can be seen that when the frost line length of the pipeline is less than 200 mm, the pipeline ice plug method is safe and feasible.

摘要

核电管道冰塞技术作为核电安全维护和创新设计的主要技术手段，对核电站的长期安全运行起到保护作用。在冰塞过程中，管道具有复杂的应力状态，容易导致材料屈服、开裂甚至损坏等问题。本研究通过搭建核电管道冰塞试验平台，对核电管道进行冰塞试验和数值分析，探讨冰塞过程中核电管道的应力分布及其对管道的影响。管道材料性能及冰塞过程中管道的安全性分析。管壁的应力分布可以通过有限元法得到。从试验和有限元结果可以看出，当管道的霜线长度小于200 mm时，管道冰塞法是安全可行的。管壁的应力分布可以通过有限元法得到。从试验和有限元结果可以看出，当管道的霜线长度小于200 mm时，管道冰塞法是安全可行的。