中文摘要：

根据新一代大型运载火箭贮箱箱底纵缝焊接系统的技术要求,设计一套工作平台进给系统。考虑了丝杠螺母副接触面和丝杠两端轴承接触面的柔性和预紧力的影响,建立了整个工作平台进给系统的柔性模态分析的有限元模型。通过10阶模态分析,得到了整个工作平台进给系统的振型和固有频率,未考虑和考虑接触面柔性、预应力影响的二者间最大误差为24.6%。第1阶固有频率对应的临界转速明显高于丝杠的最大转速,不会发生共振。并通过实验测试,验证了该工作台采用双螺母定位预紧方案的合理性和计算方法的准确性,为大型进给平台的设计提供了方法和依据。

英文摘要：

According to the requirements of tank bottom longitudinal seam welding system of the new generation launch vehicle, its working platform feeding system are designed. Considering the flexible influence between screw nut and at both ends of its bearing contact surface and pre -tightening force, its flexible modal finite element is established. By 10 orders modal analysis, its vibration mode and natural frequency are obtained, and the maximum error between considering contact surface flexibility and pre - stress influence and without considering these factors is 24. 6%. The corresponding critical rotate speed of the first order natural frequency is obviously larger than the maximum rotate speed required by the screw. Therefore, the resonance will not occur in the system. Moreover, through the experimental test, its double nut positioning pre -tightening scheme and the computing method are verified. The methods and basis for the design of large - scale feed platform are provided.