Natural frequencies of U-shaped bellows

Abstract It is assumed in this paper that the mass distribution of bellows is uniform. On this basis, the authors have deduced the equations for calculating the axial and the lateral natural frequencies of U-shaped bellows with different end conditions. This paper also discusses the influence of different amounts of axial extension and compression on the natural frequencies of bellows which either contain gas or are filled with liquids. Eleven U-shaped bellows specimens were chosen to perform experiments, applying the ‘shock’ method and the ‘resonance’ method respectively. The resulting experimental data have proven that the deduced equations are accurate enough to meet standard engineering requirements.