Archimedes screw pumps consist of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. The screw in this case is turned by a geared motor. As the shaft turns, the bottom end scoops up a volume of water or other liquid. This water will slide up inside the spiral tube, until it finally pours out from the top of the tube. The screw is usually used to move large volumes of water over short distances and heads.

The contact surface between the screw and the pipe does not need to be perfectly watertight although, the better the contact consistency, the better the efficiency, most modern designs are very accurate to start with, but also take a short period to bed-in and reach maximum efficiency.

In some designs, the screw is fixed to the casing and they rotate together instead of the screw turning within a stationary casing, but in the larger designs, the trough tends to be fixed and the screw moves within it.