Study On Finite Element Modal Analysis And Structure Optimum Design Of The Gearbox Of Twin Screw Extruder

The gearbox of twin screw extruder is the connecting part of power and working device, working under large pressure in power transmission. Gearbox itself is a component of bearable power of the whole transmission system and always in the poor working environment. The force of the gearbox is very complicated in the entire machinery work. The internal gear and shaft of the gearbox will take a bigger impact. And this impact will directly deliver to the gearbox. If the gearbox lacks of stiffness, it will deform, accelerate the attrition of the components, generate noise and affect the entire machinery’s safety and useful life. Therefore, the gearbox itself should have plenty of stiffness and strength.At present, the use of finite element modal analysis techniques to estimate the dynamic characteristics of mechanical structures has become an effective way and while the use of modern optimization techniques in the weight, deformation, stress, etc is increasingly common. This method has great significance on product designing, costs reducing, products design cycles shorted.This paper took the gearbox of twin screw extruder of Nanjing Machine Corporation as the study object and made a study of the gearbox’s dynamic characteristics by applying the method of finite element modal analysis. And then did the optimization analysis on the finite element analysis. A parameter optimization for weight of the gearbox was carried out under the conditions of static stiffness and intensity.The geometric model was built according to the gearbox of twin screw extruder drawings and then it was conducted to ANSYS to be modified and meshed. Static analysis of the gearbox was done in order to check stiffness and strength. On this basis, the modal of the gearbox was calculated by ANSYS Workbench and the top12frequencies and formations of natural and constraint modes were got. Based on the finite element analysis above, this paper discussed parameter optimum design of the gearbox, and some important parameters were selected as optimization variables. Finally, the paper drew out improved gearbox drawing.