Elements of a Gating System:
This is where the molten metal employed to manufacture the part enters the mold. The pouring basin should have a projection with a radius around it to reduce turbulence.
From the pouring basin, the molten metal for the casting travels through the down sprue. This should be tapered so its cross-section is reduced as it goes downward.
The down sprue ends at the sprue base. It is here that the casting's inner cavity begins.
Once at the sprue base, the molten material must pass through the ingate in order to enter the inner area of the mold. The ingate is very important for flow regulation during the metal casting operation.
Runners are passages that distribute the liquid metal to the different areas inside the mold.
The impression of the actual part to be cast is often referred to as the main cavity.
Vents help to assist in the escape of gases that are expelled from the molten metal during the solidification phase of the metal casting process.
Risers are reservoirs of molten material. They feed this material to sections of the mold to compensate for shrinkage as the casting solidifies. There are different classifications for risers.
Top Risers: Risers that feed the metal casting from the top.
Side Risers: Risers that feed the metal casting from the side.
Blind Risers: Risers that are completely contained within the mold.
Open Risers: Risers that are open at the top to the outside environment.