Study On Numerical Simulation Optimization Of Pillow Beam Casting Scheme

The object studied in this paper is the key part of the high-speed railway passenger car-the bolster.The casting has a complex structure and a uniform wall thickness.It is a typical high-speed,force-bearing casting.It is subjected to large impact loads during use.Safety performance is very important,its comprehensive performance requirements are extremely high.In this paper,the casting process plan of this part is designed,optimized and studied.The casting numerical simulation software is used to simulate the filling and solidification process,and the defects that may occur in the casting process are analyzed and predicted,and then the casting process is optimized and eliminated casting defects and obtaining high quality castings.Firstly,the solid model design of the bolster casting is completed.According to the material,performance requirements and structural characteristics of the bolster casting,the casting method adopts low-pressure casting.To this end,the basic design of the suitable low-pressure casting process is completed.According to the comprehensive analysis of the casting process,five pouring system schemes are designed.The casting system scheme uses the simulation software to complete the simulation calculation of the filling and solidification processes respectively,and analyzes the numerical simulation results of the velocity field and the temperature field.Through analysis and comprehensive comparison,it is found that the filling process of scheme 3 and scheme 5 is relatively stable,which can be used as the preliminary determination of the pouring system scheme.Based on the comprehensive analysis of the advantages and disadvantages of the two schemes in actual production,scheme 5 has obvious advantages,and the casting system scheme 5 is finally adopted as the actual production scheme.The bolster beam casting is a thin-wall box structure,which requires high strength and can withstand great pressure,so the role of the riser and the chill is very important.The shrinkage part of the casting appears in the large plane,and the riser is set on the large plane,which plays both the role of shrinkage and exhaust.Cold iron should be placed at the junction of the ribs in the box,which is difficult to set up.According to the low-pressure casting process design principle,the riser design and simulation optimization are first completed,followed by the cold iron design and simulation optimization.Finally,the design and simulation optimization of the vents were completed according to the filling sequence,and the process tooling design of the casting was completed based on the overall casting process optimization scheme.The actual production verification of the bolster castings was carried out by simulation optimization casting process design and production scheme.The results show that the casting performance of the castings meets the design requirements after the process optimization,and the casting defects meet the requirements of use.Therefore,the casting process plan of the high-iron bolster beam castings is feasible.It is feasible to use the simulation software to optimize the mutual verification of the process and the actual production results,and to improve the production efficiency and economic benefits of the bolster beam product.