核辅助管道Farley-Tihange现象机理分析及对策研究

摘要

Due to thermal fatigue,Farley-Tihange phenomenon frequently appears on the downstream area filled with cold and heat water of the residual heat removal heat-exchange equipment and the base metal and welding joint of the RIS and RRA pipes connected with the main coolant pipe directly in nuclear power plants in operation worldwide,which brings unacceptable defects,even worse induces LOCA.This article summarizes the recurrent position and potential risks of the Farley-Tihange phenomenon,establishes the fault tree of its failure causes,analyses failure mechanism and models of heat fatigue,presents systematically countermeasures including in-operation supervision,shutdown non-destructive monitoring,emergency maintenance preparedness and so on.%基于热疲劳的核辅助管道Farley-Tihange现象频繁出现在运行核电厂的余排热交换器下游冷、热水混合区,以及与主冷却剂管道直接相连的安全注入系统和余热排出系统管道焊缝或母材上,轻则引发超标缺陷、重则导致小LOCA（冷却剂丧失事故）。本文概括了Farley-Tihange现象典型位置和潜在风险,建立了失效原因故障树,分析了Farley-Tihange现象的热疲劳失效机理与模式,提出了包括运行监督、停堆无损监测和应急维修预案等在内的系统化应对策略。