Study On Numerical Simulation Of Casting Process For Ram Of Large CNC Boring And Milling Machine

Ram is one of the important part of large CNC boring and milling machine, its quality have great influence on the quality of the machine tool and on the degree of precision. Generally using the method of sand gravity casting to product of the casting of ram. The casting of ram belong heavy castings. It has bigger size and complicated structure. Its requirement of the casting quality is higher, which should not have pores, shrinkage and other casting defects. This essay about studying on Numerical Simulation of Casting Process for Ram of large CNC boring and milling machine which wrote base on investigate and survey, theoretical analysis and numerical simulation of FEM. By this method, acquiring data of the flow field, temperature field, stress field which about the process of casting production. Based on this conclusion, can improve the original process system and providing the basis for subsequent aging treatment. At the same time for the products appear some problems in the casting, designed a new process (mainly gating system) test was carried out.According to the actual casting process of the ram casting system, built the 3D model about casting, casting system and sand mold, then, assembled them.Using the software Pro-CAST, which is a foundry computer aided engineering (CAE) software, simulated the filling process and casting solidification process. The detail steps, first,3D model has carried on the finite element method, the discretization of the casting system is established finite element model of the mesh, second, by the actual casting process abstraction and idealization established the constitutive model of the casting,according to the process conditions set up the initial conditions and boundary conditions, and then set up to simulate the operation parameters, finally, the reprocessing calculated flow field, temperature field and stress field analysis results.Studies have shown that, through simulation analysis of field test and the new techniques, essentially consistent between the original casting process system for numerical simulation by Pro-CAST, theoretical analysis and field production. The original casting process system can ensure liquid metal filling all cavities. There are no process defects such as misrun, sand washing. Stage of solidification temperature field distribution in the spindle hole thickness much slower temperature drop, rapid temperature drop other thin parts. According the original casting process system stress analysis it is concluded that the maximum equivalent stress and equivalent stress distribution, the anti ram casting mainly bear tensile stress. The anti rain type casting gating system heat conduction effect on temperature distribution in casting production is less, and as a result of the cold iron chill effect, make the most of casting thickness a cold to go faster, get the casting quality is higher.