The Buckling And Mode Analysis Of Vacuum Transfer Line

Vacuum transfer line is the pipeline connecting the exit of oil heater to the entrance of the vacuum distillation tower in an atmospheric vacuum distillation unit, which is the most common facility found in refinery plants. It is one of the most critical pipelines in a refinery facility. Its stability/instability and vibration are causes of many safety problems. In this paper numerical analysis method is used to carry out buckling analysis and mode analysis of the vacuum transfer line.A three-dimensional finite element model (FEM) of the vacuum transfer line is constructed by using beam elements and shell elements of the ANSYS software system. Based on the three-dimensional model, buckling mode and critical loading of the vacuum transfer line under external pressure are calculated by means of the nonlinear finite element method. The effect of the thickness on the buckling critical pressure is calculated first. Then the effects of the dimension and the location of the reinforcing rid on the buckling critical pressure are explored. Also obtained is the location of the reinforcing rid while the pipe reaches the maximum critical pressure.The structural nature frequency and vibration mode of the vacuum transfer line are also investigated in this study. Especially, the effects of the stiffness of supports on the structural nature frequency and vibration mode of the vacuum transfer line are assessed. Two unique restriction structures of the vertical pipe of vacuum transfer lines are analyzed and their nature frequencies and modes are obtained. This study...