电站锅炉主蒸汽管道安全阀连接焊缝开裂分析  

Cracking Analysis of Safety Valve Connection Weld of Main Steam Pipeline of Utility Boiler

作　　者：王水安 曹福想 WANG Shuian;CAO Fuxiang(Guangdong Institute of Special Equipment Inspection and Research Foshan Branch)

机构地区：[1]广东省特种设备检测研究院佛山检测院

出　　处：《管道技术与设备》2024年第6期57-62,共6页Pipeline Technique and Equipment

摘　　要：某电站锅炉主蒸汽管道上的安全阀连接焊缝出现开裂,通过对该安全阀底座、管座及连接焊缝进行化学成分分析、硬度测定和金相分析,并利用ANSYS软件对其进行有限元分析。结果表明:安全阀连接焊缝开裂是由于管座与安全阀底座的珠光体球化、安装不规范导致应力集中、热处理不当导致焊缝硬度偏高以及安全阀底座和管座保温层缺失引起热应力过大而发生疲劳破坏。安全阀底座和管座保温层缺失引起热应力过大和疲劳是安全阀连接焊缝开裂的主要原因。The connection weld of the safety valve on the main steam pipeline of a utility boiler cracks.Chemical composition analysis,hardness measurement,and metallographic analysis were conducted on the base,pipe seat,and connection weld of the safety valve,and finite element analysis was performed using ANSYS software.The results show that the cracking of safety valve connecting weld are caused by pearlite spheroidization between the pipe seat and the safety valve base,stress concentration caused by irregular installation,high weld hardness caused by improper heat treatment,and fatigue damage produced by excessive thermal stress caused by the lack of insulation layer between the safety valve base and the pipe seat,excessive thermal stress and fatigue caused by the lack of thermal insulation layer of safety valve base and pipe seat are the main reasons for the cracking of safety valve connecting weld.

关 键 词：安全阀 连接焊缝 有限元分析 热应力 疲劳 开裂 

分 类 号：TG404[金属学及工艺—焊接]