Volume 3 Issue 2 | 2026 | View PDF
Paper Id:IJMSM-V3I2P109
doi: 10.71141/30485037/V3I2P109

Pressure-Induced Stresses at Nozzle–Shell Intersections in Pressure Vessels: An SCF-Based Analytical Approach

Walther Stikvoort

Citation:
Walther Stikvoort, "Pressure-Induced Stresses at Nozzle–Shell Intersections in Pressure Vessels: An SCF-Based Analytical Approach" International Journal of Multidisciplinary on Science and Management, Vol. 3, No. 2, pp. 79-88, 2026.

Abstract:
Accurate assessment of local stresses at nozzle–shell intersections is essential for the safe design of pressure vessels, as these regions are highly susceptible to stress concentrations under combined internal pressure and external loading. Existing design methodologies, such as WRC Bulletins, primarily address externally applied loads and do not explicitly account for pressure-induced stress intensification. This study presents empirical formulations for stress concentration factors (SCFs) to quantify pressure-induced stresses at nozzle–shell intersections in cylindrical and spherical shells, including configurations with reinforcing pads. The proposed SCFs utilize important geometric parameters and are designed to be used directly in engineering calculations, allowing them to be integrated with existing WRC-based processes via stress superposition. An example representative gives an illustration of how the method can be applied and illustrates the role of pressure-induced stresses in the overall stress condition, which may have a considerable impact on the available margin of external nozzle loads. Validation is carried out by comparative evaluation with settled analytical techniques, such as the Rules for Pressure Vessels (RfPV) and a revised Decock-based model.The findings reveal that the RfPV-based methodology offers balanced and physically consistent estimates, whereas the developed empirical methodology offers conservative estimates. The suggested methodology provides a viable model of integrating the effects of pressure-induced stress into the common nozzle design and testing. It is suitable for preliminary design, verification and screening engineering but more detailed numerical analysis is advisable in complex or critical applications.

Keywords: Pressure Vessels, Nozzle-Shell Intersection, Stress Concentration Factor, Internal Pressure, Reinforcing Pad, WRC Methods, Structural Integrity.

References:
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