Research On Casting Process Of Gearbox

Lost Foam Casting technology has much advantages, such as flexibility design,high accuracy, low production costs and pollution, etc. Thus most of the complexcases were produced by Lost Foam Casting. Because of the interaction betweenfoam and molten metal, make it is different from the conventional casting process,and the prevention from the casting defects become more difficult. Making use ofcomputer numerical simulation technology, the filling and solidification process oflost foam casting can be observed visually, the cause of casting defects can begrasped, the casting technology parameter can be optimized and the quality ofcasting can be guaranteed.In this paper, the Solidworks as3D modeling software, making use of theGeomesh software,the free edge and cross plane in the model can be repaired, andthen divide grid by use of the Meshcast module, finally it can be analyzed by use ofthe ProCAST software.Shrinkage defects always appear on the bottom of gear box produced by afoundry, so the casting can’t achieve requirements of usage. By measuring actualproduction condition, reasonable condition are setted up, then the filling andsolidification process of actual technological process are simulated, the result areanalyzed, find out the cause of Shrinkage defects. Through the numericalsimulation, that the expected effects of end gating system of actual casting processare not reached is found, on account of feeding ability is insufficient, that shrinkagedefects always appear on the thickness wall and the bottom of gear box. Theaccuracy of numerical simulation was verified by comparison between thesimulated results and the result of application.Aiming at the problems of the original process, step gating system is designed.The number of shrinkage defects is reduced by comparison between the simulatedresults of original process and the result of step gating system. Then the size ofgating system is optimized, the quality of the casting by use of the optimized gatingsystem is improved. Then the quality of casting by use of gating system three is thebest by comparison between the simulated results of different inner location gatingsystem two and gating system three. Finally, two factors of pouring temperature and vacuum which affecting thequality of casting are studied. Other factors being equal, we have determined thereasonable optimization lost foam casting of gear box, pouring temperature is1420℃, vacuum is0.05Mpa.