核电厂疏水管道焊缝开裂根本原因分析和治理建议  

Root Cause Analysis of Frequent Cracking in Butt Weld of the Drain Pipe in Nuclear Power Plants

作　　者：周帅 林磊[1] 梁帆 董艳波 徐德城[1] 王红珂 刘寅立 范敏郁 ZHOU Shuai;LIN Lei;LIANG Fan;DONG Yan-bo;XU De-cheng;WANG Hong-ke;LIU Yin-li;FAN Min-yu(Suzhou Nuclear Power Research Institute,Suzhou,Jiangsu Prov.215004,China;Yangjiang Nuclear Power Co.,Lid.,Yangjiang,Guangdong Prov.529500,China)

机构地区：[1]苏州热工研究院有限公司,江苏苏州215004 [2]阳江核电有限公司,广东阳江529500

出　　处：《中国核电》2022年第3期376-382,392,共8页China Nuclear Power

基　　金：江苏省基础研究计划(BK20170383);江苏省政策引导类计划(BZ2020057)。

摘　　要：针对核电厂倒置桶式疏水器下游管道对接焊缝频繁开裂问题,通过温度测量,应变测量及仿真计算手段分析评估某核电厂主蒸汽系统(VVP系统)疏水管道的热交变应力。结果表明,疏水过程中管道内外壁之间产生较大温差,并引起较大的热交变应力。对接焊缝内表面的热交变应力超过疲劳极限值,存在热疲劳开裂风险。间歇疏水引起的管道焊缝内表面产生超标的热交变应力是导致焊缝频繁开裂的根本原因,将间歇疏水改为持续疏水有利于解决疏水器管道焊缝开裂的问题。Butt weld in the downstream pipes of inverted bucket steam traps cracked frequently In this paper,the thermal alternating stress of drain pipe in main steam system of a nuclear power plant was analyzed and evaluated by means of temperature measurement,strain measurement and simulation calculation It finds that in the process of draining large temperature difference appeared between the innerand outerwall of thepipeline,which caused large thermal alternating stress The thermal alternating stress at the butt weld exceeded thefatigue limit,which might leadto thermal fatigue cracking.Theexcessive thermal alternating stress on the inner surface of pipeline weld caused by intermittent drainage is the fundamental cause of frequent weld cracking Changing intermittent drainage to continuous drainageis helpful tosolve theproblemof weld crackingof steam trap pipeline.

关 键 词：疏水 管道 焊缝开裂 热交变应力 疲劳 

分 类 号：TM623[电气工程—电力系统及自动化]