Abstract: A powder pumping apparatus including a pump body formed with a pumping chamber having a venturi passageway, a suction tube intersecting the pumping chamber and an air nozzle including a valve mechanism which discharges pressurized air directly into the venturi passageway of the pumping chamber to create a vacuum within the pumping chamber and suction tube to withdraw particulate powder material from a powder feed hopper. The air nozzle is carried within the interior of the pump body and has a discharge outlet located within the pumping chamber which discharges a substantially constant pressure pulse of air directly into the venturi passageway of the pumping chamber. In turn, a sharp, well-defined powder pulse is produced having a substantially homogeneous powder-to-air density throughout the duration of the pulse.