张震¹，许维鑫¹*，姜宁宁¹，刘毅²，穆振仟²，马冬霞¹，李玉胜³

1.淄柴机器有限公司，山东 淄博 255000；2.淄柴动力有限公司，山东 淄博 255000；

3.山东理工大学 机械工程学院，山东 淄博 255000

摘要：为解决某船用发动机的连杆螺栓脱落故障，现场拆检柴油机，分析故障原因；建立连杆本体、连杆端盖、连杆螺栓等零部件的三维模型，计算校核连杆本体及连杆螺栓的强度；提出提高本体强度及增大连杆螺栓直径的方案，对改进后的连杆部件及连杆螺栓进行三维仿真分析，将改进后的连杆安装于柴油机进行实际船舶应用验证。结果表明：连杆螺栓强度不足是导致连杆螺栓脱落的主要原因，改进后的连杆本体及连杆螺栓通过实船验证；改进螺栓材料、优化螺栓结构及连杆螺栓拧紧力矩方式，可以提升材料的机械性能，提高柴油机运行可靠性，有效解决连杆螺栓脱落故障。

关键词：连杆；连杆螺栓；脱落故障；应力；应变；优化改进

Abstract：In order to solve the connecting rod bolt falling off fault of a marine engine, the diesel engine is disassembled and inspected to analyze. 3D models of connecting rod body, connecting rod end cap, connecting rod bolt and other parts are established, and the strength of connecting rod body and connecting rod bolt are calculated and checked. A scheme to improve the strength of the body and increase the diameter of connecting rod bolts is proposed. The improved connecting rod components and connecting rod bolts are analyzed by 3D simulation. The improved connecting rod is installed in a diesel engine for practical marine application verification. The results show that the strength of connecting rod bolts is insufficient, which is the main reason for the falling off of connecting rod bolts. Improving the bolt material, optimizing the bolt structure and tightening torque of connecting rod bolts can improve the mechanical properties of materials, thus improve the operating reliability of diesel engines, and effectively solve the failure of connecting rod bolts falling off. This study can provide a reference for solving the shutdown failure of diesel engine caused by the falling off of connecting rod bolts.

Keywords:connecting rod; connecting rod bolt; fall off fault; stress;strain; optimization