A novel approach for steady-state creep analysis of thick-walled cylindrical pressure vessels

The goal of this study is to provide a new method forsolving the steady-state creep of thick-walled cylindricalpressure vessels. For this purpose by using an analyticalapproach, the elastic and steady-state creep problems ofthe thick-walled structures is investigated. The radial,tangential and effective stresses for the elastic and creepsolutions are obtained separately and the total stressesconsidered as the sum of elastic and creep stresses.We supposed that the rate of creep strains in the secondstage of creep was according to Norton’s law. Also therelationship of multiaxial stress and the rate of strains isrepresented by Prandtl-Reuss equations. To determinethe unknown constants of creep stresses in thick walledstructures, boundary conditions can be considered as thestress rates.The cylindrical vessel supposed to have open ends andlong length, so the analytical solution is obtained for theplane strain and plane stress conditions.The validity of proposed method for the steady statecreep solution was checked with the time dependentmethod from literature. According to the obtainedresults, the enhanced steady-state analysis can be usedto predict the creep behavior of thick-walled structuresfor a long time.

کلیدواژه ها:

Steady state creep ، thick walled cylinder ، pressure vessels ، time dependent creep