某电厂高压主汽门螺帽变形及螺栓断裂分析  

Analysis on Nut Deformation and Bolt Fracture of High-Pressure Main Valve in a Power Plant

作　　者：冯红武 沈祎侬 高瑞阳 田泽 叶建锋 FENG Hongwu;SHEN Yinong;GAO Ruiyang;TIAN Ze;YE Jianfeng(Hubei Fangyuan Dongli Electric Power Science&Research Co.,Ltd.,Wuhan Hubei 430077,China;Electric Power Research Institute,State Grid Hubei Electric Power Co.,Ltd.,Wuhan Hubei 430077,China)

机构地区：[1]湖北方源东力电力科学研究有限公司,湖北武汉430077 [2]国网湖北省电力有限公司电力科学研究院,湖北武汉430077

出　　处：《湖北电力》2022年第3期145-150,共6页Hubei Electric Power

基　　金：国网湖北省电力有限公司运维专项成本项目(项目编号:B1153221000A)。

摘　　要：针对某电厂高压主汽门螺帽变形及螺栓断裂失效,采用宏观检查、化学成分分析、硬度检测、金相及断口分析等试验,分析螺帽变形及螺栓断裂原因。结果表明:不合理的焊接加工,导致螺帽过热,在使用过程中发生高温蠕变而变形;粗大的金相组织导致螺栓内部产生微裂纹,在外力作用下最终断裂。Aiming at the nut deformation and bolt fracture failure of high-pressure main valve in a power plant,this paper uses macroscopical examination,chemical composition analysis,hardness testing,metallography and fracture analysis and other tests to analyze the cause of nut deformation and bolt fracture. The results show that inappropriate welding process results in the nut overheat and deformation due to high-temperature creep in the process of use,and that the coarse metallographic structure leads to micro-cracks inside the bolt,and finally the bolt breaks under the action of external forces.

关 键 词：高压主汽门 金相组织 螺帽 变形 螺栓 断裂 高温蠕变 微裂纹 

分 类 号：TK264.2[动力工程及工程热物理—动力机械及工程] TG142.73[一般工业技术—材料科学与工程]