超超临界600MW机组高压旁路阀螺栓失效分析  

ANALYSIS OF BOLT FAILURE FOR HIGH PRESSURE BYPASS VALVE OF ULTRA-SUPERCRITICAL 600 MW UNIT

作　　者：郑坊平[1] 崔雄华[1] 王弘喆[1] 唐丽英[1] 崔锦文[1] 

机构地区：[1]西安热工研究院有限公司,陕西西安710032

出　　处：《热力发电》2012年第8期86-90,共5页Thermal Power Generation

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.

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 

分 类 号：TG146.1+5[一般工业技术—材料科学与工程]