摘要
某电厂超超临界600MW机组的高压旁路阀部分螺栓发生不同程度地损坏,通过宏观检验、合金成分分析、力学性能检验、金相检验及能谱分析等方法,对螺栓失效原因进行分析。结果表明:螺栓失效原因为应力腐蚀开裂,与螺栓原材料固溶处理状态较差、硬度过高及螺纹加工硬化有关。对此,提出了加强备品螺栓检验,控制安装时的预紧力,避免污染腐蚀等预防措施。
Through macroscopic inspection,alloy composition analysis,mechanical property detection,metallographic examination,fracture analysis,and energy spectrum analysis etc.,the causes leading to bolt failure of high-pressure bypass valve for an ultra-supercritical 600 MW unit have been analysed.Results show that the failure was due to stress corrosion cracking,which was mainly resulted from bad solid-solution treatment of bolt raw material,too high hardness,and work hardening of threads.For this,some preventive measures,such as strengthening inspection of spare bolts,controlling the pretightening load during installation,and avoiding pollution and corrosion etc.,have been put forward.
出处
《热力发电》
CAS
北大核心
2012年第8期86-90,共5页
Thermal Power Generation
关键词
600
MW机组
高压旁路阀
螺栓
应力腐蚀
固溶处理
加工硬化
600 MW unit
high-pressure bypass valve
bolt
stress corrosion
solid-solution treatment
work hardening
