Fintte Element Analysis On Filling And Solidification Process And Thermal Stress Of Big Lathe Bed

This paper selected the machine bed that was manufactured of the material HT250as the research object，there have been designed three different casting solutions, thenthese three scenarios were simulated casting, after that, the distribution of these threeprograms’ temperature field and stress field were got, then the simulated results of thethree options were compared, and the defects generated on each program wereanalyzed. At last, by comparing the pros and cons of the three programs, the resultsprovide the basis for optimizing the process and reducing defects.This paper carries through three dimension solid modeling to the machine bedbased on UG, and discussed the interface mode between the mesh division module ofthe simulation software ProCAST and three dimension solid modeling software UG,the PARASOLIDS file format was selected as the interface mode to the mesh divisionmodule MeshCAST through actual operation, and the mesh file can be well used intosubsequent calculations with the software ProCAST.By carrying through the Numerical Simulation Calculation to the temperaturefield and stress field of the machine bed under three different scenerios with thesimulation software ProCAST, after that the simulation results of the three differentscenerios were analyzed and contrasted. To make the results more convincing, thecurves and graphs have been compared. The final result is: To the temperature field,from both how the temperature field was distributed and the sequential solidification,the result of the Scenerio3is the best. To the stress field, the stress field distribution ofScenerio3is very well, but some part would present stress concentration. The stressfield distribution of Scenerio2is worse than Scenerio3, but there is no obvious stressconcentration in Scenerio2.Thus, to the stress field, both Scenerio2and Scenerio3have their own advantages and disadvantages.To the distortion of the machine bed, Scenerio3produced the smallest distortion,and Scenerio1produced the biggest distortion. By analyzing the shrinkage cavity, theresult was got, that the area of Scenerio1nearby the pouring system inside themachine bed had a rather large possibility of forming shrinkage cavity, and Scenerio2and Scenerio3basically didn’t form shrinkage cavity. Through studying the hotcracking, the result was got, that the hot cracking tendency of Scenerio3is the smallest, and the hot cracking tendency of Scenerio2is the biggest.Considering the temperature field, stress field, distortion, possibility of formingshrinkage cavity and hot cracking tendency, Scenerio3is the best among the threescenerios. In the actual production, the machine bed was casted through Scenerio3,and the result is very satisfactory. And this proves that the simulation result correspondwith the actual situation.