STRENGTH ANALYSIS AND STRUCTURAL OPTIMIZATION OF U-SHAPED BELLOWS

In this paper, an analysis of the strength of U-shaped bellows is presented. First, an elastic solution of the action of internal pressure and axial displacement is obtained by adopting the thin toroidal shell theory, which coincides extremely well with Anderson's (Analysis of stress in bellows. Part II. Mathematical. NAA-SR-4527, 27 May 1965) and Hamada and Tanazono's (Bull. JSME, 9(35) (1966) 22-513) theoretical solutions; furthermore, these results have been tested by strain gage measurement. Secondly, a curved beam model is used for the elastoplastic analysis of bellows. With the consideration of strain concentration, the fatigue life predicting formula for the bellows expansion joint is derived and validated by the results of fatigue tests. Finally, the structural optimization of U-shaped bellows is carried out with the object of minimizing the maximum elastoplastic strain under the action of displacement. © 1990.