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
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