Gating system design and casting simulation application for the grooved worm wheel by using zinc alloy sand casting process

Bottom-up gated filling system was performed to produce worm wheel through a sand casting of zinc alloy. It was a symmetrical design in which two worm wheels were cast at once, the worm wheel was erected in the direction of gravity and had a gating system in which molten zinc alloy were poured from below. The recovery rate of the designed mold cavity was 60%. Casting analysis was performed to check that the worm wheel was sequentially filled without turbulent flow as the molten zinc alloy passed through the gate. Though the speed of the molten zinc alloy initially poured was unstable, it became stabilized while maintaining a constant speed due to the continuous inflow. The results of directional solidification were confirmed. An integrated mold cavity pattern was fabricated by 3D printer, and sand mold were manufactured accordingly. A sound worm wheel without defects could be fabricated through sand casting.