The objective of this paper is to determine the plastic limit moment for cylindrical vessels with a nozzle under in-plane moment loading. Three full scale test models with different d/D ratios were fabricated for the experiment. A three-dimensional nonlinear finite element analysis was also performed. The plastic limit moment of the cylindrical vessel-nozzle connections was determined approximately by the twice-elastic-slope criterion. The results indicate that the plastic limit moments obtained by the experiment and finite element analysis are in good agreement. On the basis of the above results, a parametric analysis of the plastic limit moment for cylindrical vessels under in-plane moment on the nozzle was carried out, and an empirical formula is proposed. The results can serve as a supplement to the available data of plastic limit load for cylindrical vessel-nozzle connection structures under external load.

Issue Section:
Design and Analysis
Keywords:
elastic limit, finite element analysis, nozzles, plasticity, pressure vessels, shapes (structures), vessel-nozzle connection, in-plane moment, plastic limit load, experimental study, finite element analysis
Topics:
Finite element analysis, Nozzles, Stress, Vessels, Deformation
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