Ore falls from the muck pile through a converging pass into a draw-point gate. Bigger, wetter fragments interlock into a self-supporting arch (a "hang-up") that throttles flow; a wider gate and a fresh blast counteract it:
risk = min(0.94, 0.72·size + 0.055·moist − 0.35·gate − 0.7·cleared)
speed = gate·(1−risk)·1.8
flow = speed·1180 t/h
Fragment size and moisture push the risk up; gate opening and a blast (which sets cleared, decaying over a few seconds) pull it back down. When risk approaches its cap the stream visibly stalls near the gate — a real draw-point hang-up — until you widen the gate, drop the fragment size, or blast it clear.
- Funnel — the pass narrows toward the gate, same as the rock walls in a real ore pass.
- Gate bar — its width is the current opening; particles pile against it when risk is high.
- Blast — instantly knocks the risk down and gives a short speed boost while it decays.