Stress analysis of plain dent on pipeline based on finite element method

For the typical plain dent on pipeline,according to the actual operation situation of the pipeline,the finite element models were established. When other parameters were invariable, a large number of calculations were carried out by changing dent depth,pipe wall thickness,pipe diameter and longitudinal dent length. The calculation results were sorted,inducted, and plotted. On this basis,the results were analyzed by single factor and multiple factors analysis,and then the changing rules between the stress and various parameters were obtained. Non-linear regression analysis was utilized to fit the results. The results show that the relationships between the maximum stress in the dented pipeline,the dent depth,wall thickness,diameter of pipeline,and the longitudinal length of the dent were modeled by sine,index,linear and semi-log liner function,respectively. Some specific expression are obtained in certain range.