Structure Finite Element Analysis And Development Of Design System To Pressure Vessel With Large Opening

Pressure vessel which was widely used in various industries is a kind of pressure-bearing equipment. In order to meet the needs of the process and structure, the openingmust be taken in the wall of the vessel. After the opening on the vessel, the high localstress appeared around the hole edge. Damage phenomenon would be produced if thelocal stress went beyond the ultimate strength of materials. Therefore, the reinforce-ment must be created around the hole edge, that is the so-called reinforcing treatment.The usable scope of the equal area reinforcement method which rooted in GB150waslimited. With the increasing of production, large diameter equipment and large pipeappeared constantly. The calculation method in GB150was out of commission. There-fore, a new calculation method to the large opening was badly in need.In this article, the large opening structure of a pressure vessel which is beyond thetraditional design method was analyzed by the use of ANSYS software, and thestrength check the of large opening structure was taken with the use of the stressclassification assessment method in JB4732-95, at the same time, the thickness of thecylinder and the tube wall, the width and thickness of the reinforcement pad wereoptimized by using the optimizing tool of ANSYS. Then the minimum value ofparameters above which meet the design conditions (admissible stress of the material)can be got. Calculation and strength assessment method which plays a guiding role inanalysis and design of pressure vessel with large opening reinforcement was found.The content of this article was divided into the following several aspects.Firstly, the large opening structure (without and with reinforcement) of pressurevessel which was in the thermal-stress coupled field was analyzed, and then the resultswere linearized processing with the use of the stress classification assessment methodin JB4732-95, in this way, the stress classification results were obtained and thestrength check. was carried out according with standards.Secondly, the finite element model was checked by the use of variety of domestic and abroad standards including the new version GB150-2011, ASME-the Americansociety of mechanical engineers, ГОСТ-National standard of Russian federation andso on. Then with the comparison and confirmation to result of finite element stressanalysis, the conclusion was got.Thirdly, the thickness of the cylinder and the tube wall, the width and thickness ofthe reinforcement pad were optimized by using the optimizing tool of ANSYS. Andthe minimum value of parameters above which meet the design conditions (admissiblestress of the material) can be got which is the most material-saving and economicdesign scheme.Finally, executive program was compiled by the use of the Visual Basicprogramming language and the secondary development function of ANSYS software.Calculating and outputting result automatically can be achieved in human-computerinteraction interface.The finite element analysis result of this research was compared and confirmedwith domestic and abroad standards, and the conclusion was proved to be correct. Theachievement of this research promoted the intensive study of stress analysis andoptimization design to the large opening on cylindrical shell.