Comparison between different design approaches to prevent buckling of torispherical heads under internal pressure

Abstract

Under the action of internal pressure compressive circumferential stresses develop in the knuckle region of torispherical heads making them susceptible to buckling. Current pressure vessel design codes such as the European Unfired pressure vessel code MSA EN13445 Part 3 present buckling as a failure mode that needs to be prevented. The latest version of the code has a Design by Analysis route that requires the designer to perform a buckling check on the design model. This study considers the different design approaches (Design by Analysis and Design by Rule) presented in MSA EN13445 Part 3 and compares computational results with experimental data available from literature. The study shows that the pressure vessel design code MSA EN13445 Part 3 guarantees that the calculated design load will not subject torispherical heads to buckling in the knuckle region, under the action of internal pressure.