New Criterion for the Definition of Plastic Limit Load in Nozzle Connections of Pressure Vessels

Abstract

In this research, a new criterion for determining the plastic limit load in shell intersections using elasticplastic finite element analysis is presented. Using the proposed maximum criterion of the rate of the change of the relative plastic work (PW), a numerical procedure is described to define the plastic pressure. Also, a specific plastic work criterion is presented using a local deformation parameter. Results of comparisons with different criteria were considered for experimental models of cylindrical vessels with radial and nonradial (lateral) nozzles. A parametric study of the radial intersections of cylindrical shells under the internal pressure loading was performed to examine the influence of the diameter ratio on the plastic limit pressure on the basis of the proposed criteria.