Study on analysis methods of post-buckling bulging deformation behavior of bellows subjected to internal pressure

Tsukimori, Kazuyuki; Ando, Masanori ; Yada, Hiroki ; Arakawa, Manabu*; Kitagawa, Keita*

Bellows with relatively small number of convolutions yields so called in-plane squirm due to over internal pressure. However, still its boundary function is maintained and bulging deformation lasts with increase of pressure until burst occurs. The seamless FEM analysis from in-plane squirm to final bulging becomes very difficult, since many contacts between convolutions occur during this process. In this study to avoid this difficulty, two analysis methods, i.e., implicit analysis with artificially moving bellows end and quasi-static explicit analysis, were tried and their results were discussed compared with experimental results.