Load-Carrying Analysis Of Large Bellows

Because of excellent deformation compensation ability, bellows is widely used in petroleum, chemical, power and many other fields. With the development of industries, more and more large bellows are needed and how to economically design the bellows structure in the premise of safety becomes increasingly important.In this paper, finite element analysis was performed to investigate the load-carrying abilities of large bellows with the purpose of promoting the application scope of the bellow code.Firstly, finite element models for the large bellows were established with ANSYS software. Stress magnitude and distribution were analyzed separately under internal pressure loading or axial displacement loading and the results were compared with the theoretical ones calculated based on the design standard of the bellows. It is found that GB16749-1997 is still applicable for the strength calculation of the bellow. But it is also found that the larger the size of bellows, the less conservative of strength calculation based on the bellows code.Secondly, the influence of bellows'diameter and thickness on the stress and ultimate load-carrying ability was analyzed by means of finite element analysis. It is found that with increasing the bellows'thickness, the longitudinal stress will decrease under internal pressure loading, but increase under axial displacement loading.Finally, both linear stress analysis and plastic limit analysis were used to compute the load-carrying ability of the large thin reinforced U-shaped bellows. Results show that compared with the unreinforced U-shaped bellows, most stresses in the reinforced U-shaped bellows are decreased by 20% to 80%, and the limit load is increased by 3 times.