新车型开发中螺纹紧固件拧紧扭矩的开发

Development of Tightening Torque of Thread Fasteners in the Process of New Vehicle Development

通过控制紧固件的扭矩对预紧力进行控制,是目前保证螺纹紧固件装配质量最常用的方法。拧紧力矩设定的正确性和拧紧质量是影响螺纹紧固件装配质量的重要因素。文章以某车型轮胎螺栓的拧紧力矩为例,通过制定拧紧力矩标准分析流程,使用Schatz多功能螺栓拧紧工艺分析系统,根据紧固件-扭矩/预紧力试验结果得出影响拧紧质量的各种参数值,表明螺纹摩擦因数、支撑面摩擦因数、扭矩系数、预紧力参数及标准件规格的综合关系决定了扭矩的设定值,其中摩擦因数的波动对扭矩转化为预紧力的影响最大,最后给出设定拧紧力矩和拧紧策略的参考建议。该方法为螺纹紧固件拧紧力矩的开发提供参考。

At present, control of clamp force is most widely used to ensure the quality of thread fastener assembly. And control of clamp force could be achieved through controlling the tightening torque. The setting of tightening torque value and quality of tightening has strong impact on quality of thread fastener assembly. Taking the tightening force of the tyre bolt as an example,through setting up the standard process flow of the tightening force and using Schatz multi-functional thread fastener analyzing system to obtain the various values that affect the tightening force quality based on the test results of fastener＇s torque/pre-tightening force, indicating that the relation among the friction coefficient of thread, the friction coefficient of supporting surface,the torque coefficient, the parameters of pre-tightening force and the specifications of standard part affects the setting of the torque, the fluctuation of the friction coefficient has a great impact on the conversion from the torque to pre-tightening force.Finally, the suggestions for setting the tightening torque and tightening strategy are put forward in this paper. This method will provide the reference for the development of tightening torque of the thread fastener.