某柴油机试验台连杆断裂失效分析及改进  

Fracture Analysis and Improvement of Connecting Rod of A Diesel Engine Test-bed

作　　者：陈康 肖朝南 李亚洲 郭元 范希杰 屠力月 CHEN Kang;XIAO Chaonan;LI Yazhou;GUO Yuan;FAN Xijie;TU Liyue(National Engineering Laboratory for Marine and Ocean Engineering Power System,Chongqing 402160;Chongqing Key Laboratory of the High-Power Diesel Engine Fuel Injection System,Chongqing 402160;Chongqing Yuejin Machinery Co.,Ltd.,Chongqing 402160)

机构地区：[1]船舶与海洋工程动力系统国家工程实验室,重庆402160 [2]大功率柴油机燃油喷射系统重庆市重点实验室,重庆402160 [3]重庆跃进机械厂有限公司,重庆402160

出　　处：《内燃机》2022年第2期28-31,共4页Internal Combustion Engines

基　　金：中船科发【2021】748号。

摘　　要：某柴油机轴瓦实验台连杆发生断裂,通过断口形貌分析及化学成分、力学性能、夹杂物等材料检测分析判断其为疲劳断裂。通过受力分析确定危险截面,并通过有限元方法研究连杆的应力分布。结果表明连杆小头在平行于接合面且靠近内壁处开设的螺纹孔引发的应力集中是造成本次连杆断裂的根本原因。据此对连杆结构进行了改进,实施了取消螺纹孔等改进方案,耐久试验结果表明改进效果良好。The connecting rod of a diesel engine bearing pad test bench is fractured, and it is judged to be fatigue fracture through the analysis of fracture morphology and the detection and analysis of chemical composition, mechanical properties, inclusions and other materials. The dangerous section is determined by force analysis, and the stress distribution of the connecting rod is studied by FEA. The results show that the stress concentration caused by the threaded holes which is parallel to the joint surface and close to the inner wall of the connecting rod are the root cause of this fracture. Based on this, the structure of the connecting rod is improved, and the improvement schemes including the cancellation of the threaded holes are put forward, and the experimental verification result shows that the improvement is effective.

关 键 词：柴油机 试验台连杆 断裂 改进 

分 类 号：TK403[动力工程及工程热物理—动力机械及工程]