Firstly, according to the calculation results, the 3D pouring model of the seat body is drawn in Pro / E software, and the intermediate file is output and imported into the numerical simulation software for simulation. It is estimated that the number of variable meshes will be 10 million, as shown in Figure 1, which is the mesh division diagram of numerical simulation finite element model. In order to ensure the principle of high temperature tapping and low temperature pouring, the melting temperature of seat casting is 1620 ℃ and the pouring temperature is 1560 ℃. The pouring time was 72 s, and the furan resin sand and initial temperature were set at 25 ℃; The interfacial heat transfer coefficient of the mold is 500W / (m · 2K). After the parameters are set, the SOR iterative method is used to simulate the mold filling and solidification process of castings.
The shrinkage of zg310 seat is large during solidification and cooling. In order to prevent shrinkage porosity, shrinkage cavity and other defects in the position with large wall thickness in the casting, numerical simulation analysis is needed; Figure 2 shows the temperature field of seat casting at different times during solidification.
It can be seen from Fig. 2 that in the initial solidification stage of the casting, the distal edge begins to solidify first. Fig. 2A shows that the solid rate is 30%, and the thin wall with small size in the middle of the upper and lower edges of the casting gradually begins to solidify; Fig. 2B shows that when the solid content is 70%, the top riser also gradually begins to solidify; Fig. 2C shows that when the solid rate is 98%, the area near the lower central circular hole of the riser is the final solidification area, and the complete solidification time is 12499s.