The Archimedes screw is an ancient invention that continues to be important in the modern world. This tool had many historical uses. It was used to empty water out of leaking ships and flooded mines. Fields of crops were watered by using the screw to pull water from lakes and rivers.
It was also used to reclaim flooded land, for instance in Holland where much of the land lies below sea level. There are a few different designs of the Archimedes screw, but the key feature is the angled spiral around a center shaft the typical screw shape. The screw can sit in a half pipe trough or a full pipe.
Procedure Fill one of your containers with water. Optionally, you can add food coloring to make the water easier to see when it is in the tubing. Elevate the second empty container so it is higher than the first container. Place one end of your Archimedes screw in the lower container of water, and align the other end over the upper container. Rotate the screw so the bottom end of the tubing "scoops" water with each rotation.
It should go underwater and then come back above the surface with each revolution and not remain completely submerged the entire time. If you do not see your tubing start to fill with water after a few rotations, you might be spinning the screw the wrong direction. When you look at your screw from the side, what do you see?
How is the water distributed in the tubing? Keep rotating the screw, and watch as the water moves up into the higher container! Try different ways of using your Archimedes screw. How high can you lift water? Raise the upper container, and tilt the screw upward at a steeper angle. Do you reach a point where water starts to flow back down the tube instead of up?
Extra: Try different designs of your Archimedes screw. What happens if you change the spacing of the tubing spiral, making the individual turns closer together or farther apart? What if you change the diameter of the PVC pipe or the tubing? Build a Cooler. Get smart. Sign up for our email newsletter. Sign Up. Support science journalism. Knowledge awaits. See Subscription Options Already a subscriber?
The rollers carry most of the radial load. The Archimedes Screw is still used today in some limited applications usually electrically-powered , and can range in size from a quarter of an inch to nearly 4 meters 12 feet in diameter.
A large screw or banks of screws may be used to pump rainstorm runoff or to lift water or wastewater, for example. Archimedes' screws, now called screw conveyors, are also used today primarily to propel dry bulk materials. However, if you do not have access to a generator pump and need a low-tech solution to raise water, it doesn't get much easier and low-tech than an Archimedes' screw. The distribution, today, of the water lifting Archimedes Screw is in the Nile-delta region of Egypt.
A major advantage of these pumps is variable pumping at constant speed, because the output up to design capacity is controlled by the sump level and equals the influent flow rate. The disadvantages are the inducement of turbulence, the release of odors and other volatile substances if using for wastewater , and the relatively high initial cost if using metal components, but not wooden.
But when comparing costs with those of other types of pumps, consider the cost of the total system, including all piping, wet or dry wells, screens, fittings, valves, variable-speed controls, and other accessories as well as operating and maintenance costs. Note that operators like screw pumps because the good ones, when properly installed, are so trouble-free.
This small scale Archimedes Screw is a model to understand the concept of the water lifting device. The ones built by farmers are made of bamboo or other wood, usually. A working Archimedes Screw can be made using local or cheap materials in your region.
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