超临界机组小汽轮机高调门调速油伺服阀螺栓断裂的原因
Fracture Reason of Servo Valve Bolt of Electrohydraulic Oil of High Regulating Valve of Small Steam Turbine in Supercritical Unit
摘 要
某电厂超临界机组小汽轮机高调门调速油伺服阀螺栓工作3.5 a后发生断裂，采用化学成分分析、硬度检验、金相分析和断口分析等方法对断裂原因进行了分析。结果表明：螺栓的断裂性质为疲劳断裂，断口呈现多源特征；螺栓的螺纹部位存在多处机加工缺陷，疲劳裂纹在缺陷处萌生，在复杂疲劳载荷作用下扩展，当裂纹扩展到临界尺寸后出现失稳引起瞬时断裂；当一根螺栓疲劳断裂后，其他螺栓因承受的静载荷明显增大而发生瞬间过载断裂。
小汽轮机
伺服阀
螺栓
断裂
supercritical unit
small steam turbine
servo valve
bolt
fracture
Abstract
Servo valve bolt of electrohydraulic oil of high regulating valve of small steam turbine in supercritical unit in a power plant fractured after working for 3.5 a. The fracture cause was analyzed by methods such as chemical composition analysis, hardness testing, metallographic analysis and fracture analysis. The results show that the fracture property of the bolt was fatigue fracture, and the fracture presented multi-source characteristics. There were many serious manufacturing machining defects in the thread of the bolt. Fatigue cracks initiated in these defects and propagated under complex fatigue load. The cracks became unstable when propagated to critical size, leading to the instantaneous fracture. The static load on the other bolts increased signi ficantly after the fatigue-fracture of one bolt, leading to the instant fracture under overload of the other bolts.
中图分类号 TG157 DOI 10.11973/jxgccl201905016
所属栏目 失效分析
基金项目
收稿日期 2018/12/27
修改稿日期 2019/4/1
网络出版日期
作者单位点击查看
备注朱海宝(1983-),男,安徽合肥人,高级工程师,硕士
引用该论文: ZHU Haibao,LI Ge,CHEN Zhuoting,LIU Ming. Fracture Reason of Servo Valve Bolt of Electrohydraulic Oil of High Regulating Valve of Small Steam Turbine in Supercritical Unit[J]. Materials for mechancial engineering, 2019, 43(5): 75～78
朱海宝,李戈,陈卓婷,刘明. 超临界机组小汽轮机高调门调速油伺服阀螺栓断裂的原因[J]. 机械工程材料, 2019, 43(5): 75～78
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参考文献
【1】吴志祥,杨建国.火电厂驱动汽动泵的小汽轮机保安系统的故障分析[J].电力建设,2005,26(5):11-13.
【2】姜先军,柳薇,单福泉.EH油系统供油装置在火力发电厂的应用[J].通用机械,2011,10(7):62-67.
【3】蔡文河,严苏星.电站重要金属部件的失效及其监督[M].北京:中国电力出版社,2009:70-85.
【4】李玲.管道阀门螺栓断裂的原因分析[J].机械工程材料,2013, 37(5):106-110.
【5】林轻,杨兴林.某型高强度螺栓断裂失效分析[J].热加工工艺,2009,38(2):128-130.
【6】杨建菊,王庆,王志永,等.某电厂GH4145/SQ螺栓钢材质分析[J].热力发电,2007,36(5):83-86.
【2】姜先军,柳薇,单福泉.EH油系统供油装置在火力发电厂的应用[J].通用机械,2011,10(7):62-67.
【3】蔡文河,严苏星.电站重要金属部件的失效及其监督[M].北京:中国电力出版社,2009:70-85.
【4】李玲.管道阀门螺栓断裂的原因分析[J].机械工程材料,2013, 37(5):106-110.
【5】林轻,杨兴林.某型高强度螺栓断裂失效分析[J].热加工工艺,2009,38(2):128-130.
【6】杨建菊,王庆,王志永,等.某电厂GH4145/SQ螺栓钢材质分析[J].热力发电,2007,36(5):83-86.
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