某核电厂18PA6B柴油机发生连杆螺栓断裂事故失效原因分析与研究  

Failure Causes of Connecting Rod Bolt Fracture Accident in 18PA6B Diesel Engine of a Nuclear Power Plant

作　　者：谢毅晖 张云华[2] XIE Yihui;ZHANG Yunhua

机构地区：[1]国电投核电技术服务有限公司,山东烟台265116 [2]上海核工程研究设计院股份有限公司,上海200233

出　　处：《科技创新与应用》2024年第33期5-8,共4页Technology Innovation and Application

摘　　要：某核电厂备用柴油发电机组A列按计划执行设备季度试验(满功率试验)过程中,A8缸活塞连杆螺栓断裂,连杆飞出击破A8缸曲轴箱盖板,伴随大量润滑油及冷却水泄漏,现场人员立即紧急停机干预,柴油发电机停机。针对此次事件,该文结合事故后受损零部件的检验报告开展连杆螺栓断裂原因分析,其中A8-1和A8-2连杆螺栓分别有1处和2处断口,A8-1连杆螺栓断口和A8-2连杆螺栓断口1的断口形貌均为双向弯曲疲劳断裂,A8-2连杆螺栓断口2的断口形貌为弯曲过载断裂。通过断口形貌及柴油发电机运行情况,可以判断出连杆螺母松退导致A8-1和A8-2连杆螺栓断口1发生双向弯曲疲劳断裂,从而引起其他部件损坏。最后,为避免该类型事件发生,提出一些建议。During the quarterly equipment test(full power test)of the spare diesel generator set of a nuclear power plant as planned,the piston connecting rod bolt of cylinder A8 broke,and the connecting rod flew out and broke the crankcase cover plate of cylinder A8.Accompanied by the leakage of a large amount of lubricating oil and cooling water,on-site personnel immediately stopped the emergency and intervened,and the diesel generator was shut down.In response to this incident,this paper analyzes the causes of the connecting rod bolt fractures based on the inspection reports of damaged parts after the accident.Among them,the A8-1 and A8-2 connecting rod bolts have 1 and 2 fractures respectively.The fracture morphology of the A8-1 connecting rod bolt fracture and the A8-2 connecting rod bolt fracture 1 are both bidirectional bending fatigue fractures,and the fracture morphology of the A8-2 connecting rod bolt fracture 2 is bending overload fracture.Through the fracture morphology and the operating conditions of the diesel generator,it can be determined that the loosening of the connecting rod nuts causes the two-way bending fatigue fracture of the A8-1 and A8-2 connecting rod bolts fracture 1,which causes damage to other components.Finally,some suggestions are put forward to avoid this type of incident.

关 键 词：柴油发电机组 连杆螺栓 失效原因分析 断口 螺母 

分 类 号：TM623[电气工程—电力系统及自动化]