The flow of liquid metal in filling process has a great influence on the quality of casting. If the design of casting system is unreasonable, casting defects such as insufficient pouring, cold insulation, sand flushing and coil gas will often occur in casting. The filling process of liquid metal simulated by ProCast can be used to judge whether the casting system can meet the requirements.The figure shows the filling process of liquid metal for castings.The liquid metal begins to flow from the inner runner into the cavity as shown in Figure (a).The liquid metal of the four inner runners in the middle flows from the vicinity of the guide rail, along the guide rail and the middle to the other end of the mold, while the liquid metal of the two inner runners in the outermost direction flows through the outer wall and uphill on both sides as shown in Figure (b).
When the liquid metal flows to the far end of the casting, it fills the mold smoothly and rapidly and fills the cavity 40.8s after pouring the liquid metal as shown in Fig. (c), (d).The simulation results show that the filling time is 40.8s, which conforms to the design results of the pouring system (45 s).During the filling process, the liquid metal passes through the runner, the runner and the inner runner through the gate cup under the action of gravity and then enters the cavity. The liquid level rises gradually from bottom to top until the cavity is filled.
Due to the large number of internal gates and the large spacing, the low speed through the internal gate makes the liquid metal flow into the cavity smoothly and has little impact on the bottom of the cavity. The liquid metal enters the top of the cavity along the wall of the cavity during the flow process, which will not cause great impact on the sand mold, and there is no obvious air entrainment during the filling process.
Temperature field of filling process can see that the temperature of liquid metal decreases slowly. Even at the edge of the casting, the temperature of liquid metal is still above the liquid line, which is advantageous to the later solidification and contraction. The liquid metal is filled with cavity and thus will not cause defects such as underfilling and cold insulation.