摘要
采用宏观观察、金相分析、硬度试验、断口扫描电镜分析和能谱分析,对某燃气-蒸汽联合循环机组余热锅炉高压旁路阀门开裂原因进行分析。结果表明:高压旁路阀门阀壳内壁开裂类型为腐蚀性热疲劳+应力腐蚀。机组启停频繁、负荷变化大,造成高压旁路阀门减温水的频繁投入,导致阀壳内壁表面存在较大的交变热应力,在交变热应力及腐蚀性环境的作用下,阀壳内壁处发生腐蚀性热疲劳开裂,在扩展过程中伴随应力腐蚀开裂。
The micro observation,metallographic analysis,hardness test,SEM and EDS analysis for fracture were adapted to analyze the cause of cracking of high temperature value in gas steam combined cycle unit.The results show that the cracking mode of inner wall of value is thermal fatigue combined with stress corrosion.The value was under frequent desuperheating water input due to large fluctuating of load or frequent start-stop.That leads to large alternating stress at inner wall of value.Combined with corrosive environment,corrosive thermal fatigue crack appears at inner wall of value,combined with stress corrosion during extending of cracks.
作者
刘义忠
卢振宇
杨哲一
崔雄华
LIU Yi-zhong;LU Zhen-yu;YANG Zhe-yi;CUI Xiong-hua(Guangdong Zhujiang natural gas power generation Co.,Ltd.,Guangzhou 511458,Guangdong,China;Xi'an Thermal Power Research Institute Co.,Ltd.,Xi'an 710054,Shanxi,China)
出处
《阀门》
2023年第2期244-247,共4页
VALVE MAGAZINE
关键词
燃气-蒸汽联合循环
铸造高温阀门
热疲劳
应力腐蚀
gas steam combined cycle
cast high temperature value
thermal fatigue
stress corrosion
