Finite Element Analysis Of The Nozzle Reinforcement Structure Of Internal Pressure Cylinder Vessel

The cylindrical shell structures with all kinds of nozzles and radial joint pipe have been widely used in the fields of petroleum,energy sources,nucleus and other aspects in the need of craftworks and structures. This not only reduces the intensity of the shell,but also causes the high local stress nearby the hole. In addition, because of the stresses produced by various loads in the joint pipe, different stresses produced by temperatures, material of shell, manufacturing craftworks and other reasons. These reasons make the areas become the most weakly sector. So it is necessary to design the structure style of the joining part between the piping and shell, for example, adopt the more thick joint pipe or the more thick shell. This can enhance the shell intensity and reduce the stress concentration coefficient under the scope of safely values. But because of the changes of the geometry parameters, methods of manufacture and types of loads, it is difficult to calculate the stress and strain in the cylindrical shell structures with nozzles. Therefore, it is an important subject to analyze the structure systematically and roundly.The paper aims at internal pressure cylindrical shell with radical nozzles without reinforcing structure, reinforcing structure and joint pipe reinforcing structure, adopting three dimensions of finite element method, investigating the distribution of the stress and the stress concentration coefficient. After the systematically analyzing, we can draw the conclusion that the structure with reinforcing circle has less stress concentration coefficient and larger limit load. In the conclusion the cylindrical shell structures with nozzles has small stress concentration factor and large limit loads when it is added the reinforcing structure. Numerical value proves the reliable of the finite element method.