Transfer Tubes

D-Series Material Transfer Pumps

Direct transfer pumps use high velocity compressed air to generate a vacuum in the inlet of a smooth bore tubular body to draw dry good in bulk and then convey it in a turbulent air stream through a hose attached to the discharge end of the pump. Plastic pellets, powder beans, peas, sawdust and continuous fabric trimmings are only a few examples of the numerous itmes that can be transferred.

These versatile pumps can also be used to convey small parts from an assembly station at a much lower cost than a pick and place device. Select a pump inner diameter that is a little larger than the part outer diameter then provide generous bends in the discharge hose for free passage of parts. For longer parts, select a pump (and discharge hose) diameter large enough for enough to pass the part diameter but not large enough for the part length. This method will eliminate end-for-end tumbling that can damage parts. At the hose discharge end, direct the parts against handling curtains or foam rubber to decelerate the parts.

Vacuum flow rate, and thus material transfer rate, is easily controlled by simply changing the compressed air supply pressure. Higher air pressure increases the transfer rate. When shutting the pump off, it is good practice to let the pump blow air for a long enough period to allow all parts in the discharge hose to exit.

Principle of Operation

Compressed air is supplied to the body port and passes through an annular ring to several nozzles leading into the transfer tube at an angle. The nozzles concentrate the air stream so that it increases to maximum velocity as it passes through the nozzle throat and into the pump transfer tube. The air jets meet in the tube center and creat a powerful vacuum at the tube inlet and a turbulent spiraling flow at the discharge end. Large quantities of ambient air are ingested along with the material being transferred and combined with nozzle air, helps to move material through the discharge hose.


Technical Data