Effect of Shear Deformation and Relaxation of Support Conditions on Buckling of Pressurized Pipelines containing Expansion Bellows

Mechanical stability of pressurized expansion bellows and tube-bellows-tube interconnects is considered.Effect of shear deformation on buckling pressure of bellows is shown y using Engesser's model. A generalized equivalent column concept is developed in order to study the effect of relaxation of support conditions on stability of interconnects containing expansion bellows. Two general modes of buckling are discussed: column instability of well-supported bellows (I) and buckling of tube-bellows--tube interconnect if the support-bellows distances are large enough (II). A dramatic drop of critical pressure in the transition region from mode I to mode II is shown.