The two main gate systems are manually trimmed gates and automatically trimmed gates. The following examples show where they are used:
1. Sprue gate: Used for large components, the gate mark is visible in component and no runner is required. e.g.: bucket molding (backside cylindrical gate mark visible and can be felt).
2. Edge gate: Most suitable for square, rectangular components
3. Ring gate: Most suitable for cylindrical components to eliminate weld line defect
4. Diaphragm gate: Most suitable for hollow, cylindrical components
5. Tab gate: Most suitable for solid, thick components
6. Submarine gate: Used when auto de-gating is required to reduce cycle time
7. Reverse taper sprue gate (Pin gate): Generally used in three plate molds.