Reasonable experimental device is designed for the measurement of thermophysical parameters of glass quartz sand used in actual sand casting production. The thermophysical parameter database that can be used for numerical simulation is obtained by using appropriate measurement methods. The correctness of the measured thermophysical parameters is verified by using the simulation software ProCAST, The heat transfer coefficient of the heat transfer process between the casting and the mold interface is determined by using the temperature data obtained from the experiment. Through the numerical simulation of a typical large steel casting frame in ProCAST, the distribution of temperature field and stress field in the sand casting process is analyzed, so as to provide a reliable analysis basis for the actual production.
The shrinkage cavity and porosity defects in the solidification process of sand castings are predicted, the tendency of crack defects in sand castings is analyzed from a macro point of view, and the stress and deformation of sand castings in the molding process are analyzed.
1) This paper summarizes the production status of sand casting for large mill stand, analyzes the main research contents of sand casting numerical simulation and the development and application status of sand casting simulation technology at home and abroad, and introduces the research status of thermophysical parameters for simulation at home and abroad.
2) This paper introduces the finite element analysis method used in the numerical simulation of solidification process, introduces the finite element analysis basis of temperature field of sand castings in the solidification process, and summarizes the analysis basis of stress field of sand castings in the solidification cooling process; The formation mechanism and prediction criterion of shrinkage cavity and porosity defects that may occur in sand castings during solidification are introduced; At the same time, the basic methods for determining the thermophysical parameters of materials are analyzed.
3) The thermophysical parameters of sand casting sodium silicate quartz sand mold were measured by the method of actual measurement and reverse calculation. The test device which can be used to test the temperature field of molding sand is designed. The test process and test instruments are introduced in detail, and the test results are analyzed and discussed. Using the temperature data obtained from the test, the thermophysical parameters of the sand mold are inversely solved, and the thermophysical parameters that can be used for numerical simulation are obtained.
4) The temperature field of sand mold is numerically simulated and verified by ProCAST software to verify the correctness of the measured thermophysical parameters. The interface mode between ProCAST and pre-processing software is deeply discussed, and the inverse module is used to solve the interface heat transfer coefficient of casting mold in the test process.
5) Combining ProCAST software with actual production, the finite element numerical simulation of a typical large steel casting rolling mill stand is studied. Analyze the temperature change law of the frame in the solidification process, discuss the temperature distribution of the specific position of the sand casting, explore the stress distribution law of the steel casting in the cooling process, and analyze the tendency of hot crack and stress deformation in the solidification process of the sand casting, so as to provide a reliable basis for the formulation of the actual sand casting production process.