Abstract: Stiffness is one of the main performance parameters of bellows which depends on the geometric dimensions, especially shell thickness of the bellows. U-shaped bellows,the most wildly used kind in engineering is commonly hydraulic pressure formed, and the deformation in board-ring is much greater than that in shell-ring. Considering that shell thickness is decreasing with increase of its radius in forming process. ,the thickness variation with redius can be described by a power function which is used to modify the commonly used empirical formula for axial stiffness calculation. Through comparison of the computational results by FEM simulation using MSC Nastran and the results by experiments the effectiveness of the method presented in this paper is verified.

Key words: vibration and wave , U-shaped bellow , variable thickness , stiffness , FEA

摘要： 刚度和工作应力是波纹管的主要特性，它们取决于波纹的几何尺寸，特别是取决于其壁厚。工程上广泛应用的U型波纹管大多具有两个特点，液压成型且环板处变形远大于环壳处。针对这两个特点，考虑到波纹管在加工成型时产生厚度随半径增大而减薄的实际现象，取厚度按半径的幂函数变化规律，对工业上常用波纹管轴向刚度计算公式进行修正。使用MSC公司的有限元软件MSC.Nastran进行仿真计算，并实测一组波纹管刚度数据。通过有限元计算和实测数据的对比，验证考虑厚度变化的必要性和有效性，解释了此公式在计算时出现结果偏大的原因，同时直观的表示出厚度变化对计算结果的影响，对实际工程应用有一定意义。