基于拧紧工艺的发动机曲轴皮带轮螺栓连接优化分析

Optimization Analysis for Bolt Cnnection of Crankshaft Pulley Based on Tightening Processes

针对某型号发动机曲轴皮带轮螺栓连接失效问题,从螺栓断口分析其失效机理,并分别对曲轴皮带轮螺栓轴力及监控方式进行理论计算和验证,设计螺栓松动实验—横向振动实验,以验证螺栓在不同夹紧力下松动(轴力衰减)情况,寻求其衰减规律;进行实物装配实验,验证理论计算结果及装配方法,以此优化曲轴皮带轮螺栓拧紧工艺,保证其连接不再发生松动疲劳失效,为后续工艺协同发动机设计提供依据。

To deal with the problem of bolt connection of a certain type of engine crankshaft pulley,the failure mechanism was analyzed from the fracture of the bolt,and the axial force and monitoring manner of the bolt were theoretically calculated and verified.The loose-bolt test,i.e.,the transverse vibration experiment,was designed to measure the conditions(axial force attenuation)of the bolt under different clamping forces in search for a law of decay.Further physical assembly experiments were carried out to test the results of theoretical calculation and to demonstrate the assembly methods,so as to optimize the tightening process of the bolt and prevent the fatigue failure of the bolt connection.The methods provide basis for subsequent processes and engine designs.