A New Technique for Approximating the Stress in Pad-Type Nozzles Attached to a Spherical Shell

Abstract

The generally applicable approximate analysis for pad-type nozzles was shown statistically to be reliable through the use of the design of experiments. The focus was on membrane stresses due to an internal pressure in discontinuous portions of the pad-type nozzle attached to a spherical shell designed in the ASME Boiler and Pressure Vessel (BPV) Code, Section VIII, Division 1. Although Division 1 does not require stress evaluations in discontinuous portions, the results given in this paper show that the maximum membrane stress can be above the yield stress for some generally used materials. This evidence will be reviewed in future work.