摘要
针对某电站锅炉投入运行数月后低温过热器出口集箱连接管弯头中性面发生泄漏的问题,通过一系列试验对连接管弯头泄漏进行了综合性失效分析。分析结果表明:锅炉安装后的煮炉过程有碱液进入过热器,浓缩碱溶液在锅炉运行环境中对管道内壁腐蚀并产生微量的氢,氢延晶界聚集引发氢脆,形成大量延晶裂纹,最终导致连接管弯头苛性脆化开裂。通过采取对存在裂纹的管段及时更换,同时对开裂连接弯头周边管段内壁进行彻底冲洗,减少管段内壁碱含量的措施,目前该锅炉运行稳定。
Aiming at a power station boiler put into operation a few months after the low-temperature superheater outlet collector connecting pipe elbow neutral surface leakage problems,through a series of tests on the connecting pipe elbow leakage for a comprehensive failure analysis.Analysis results show that:boiler installation after the cooking process of lye into the superheater,concentrated lye solution in the boiler operating environment on the inner wall of the pipe corrosion and produce a trace of hydrogen,hydrogen extension of the gathering of grain boundaries triggered hydrogen embrittlement,the formation of a large number of delayed crystalline cracks,and ultimately lead to connecting pipe elbow caustic embrittlement cracking.The boiler is now running stably through the measures of timely replacement of cracked pipe segments and thorough flushing of the inner wall of the pipe segments around the cracked connecting elbow to reduce the alkali content in the inner wall of the pipe segments.
作者
赵志明
夏静
ZHAO Zhiming;XIA Jing(Taiyuan Boiler Group Co.,Ltd.,Taiyuan 030008,China;Shaanxi Medical University,Taiyuan 030001,China)
出处
《机械工程与自动化》
2025年第4期196-197,200,共3页
Mechanical Engineering & Automation
关键词
低温过热器出口集箱
失效分析
苛性脆化开裂
延晶裂纹
outlet header of the low temperature superheater
failure analysis
caustic embrittlement cracking
ductile cracks
