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The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
A screw turbine at a small hydro power plant in Goryn, Poland. The Archimedean screw is an ancient invention, attributed to Archimedes of Syracuse (287–212 BC.), and commonly used to raise water from a watercourse for irrigation purposes.
Smith's revised 1836 patent. This is the propeller design originally fitted to Archimedes. Screw propeller of Archimedes as fitted in the stern of the ship. Smith initially had some difficulty sourcing suitable engines for the ship, as screw propulsion presented some unfamiliar technical challenges.
Archimedes' screw was turned by hand, and could also be used to transfer water from a low-lying body of water into irrigation canals. The screw is still in use today for pumping liquids and granulated solids such as coal and grain.
The first type of screw conveyor was the Archimedes' screw, used since ancient times to pump irrigation water. [1] They usually consist of a trough or tube containing either a spiral blade coiled around a shaft, driven at one end and held at the other, or a "shaftless spiral", driven at one end and free at the other. The rate of volume transfer ...
Three principal forms exist; In its simplest form (the Archimedes' screw pump or 'water screw'), a single screw rotates in a cylindrical cavity, thereby gravitationally trapping some material on top of a section of the screw as if it was a scoop, and progressively moving the material along the screw's axle until it is discharged at the top.
Archimedes wrote the earliest theoretical study of the screw as a machine, [13] and is considered to have introduced the screw in Ancient Greece. [9] [14] By the first century BC, the screw was used in the form of the screw press and the Archimedes' screw. [10]
Instead of the central pin and string of the string compass, this device uses a non-rotating shaft (column) with helical threads (screw; see Archimedes’ screw) to which are attached two slotted arms: one horizontal arm is affixed to (travels up) the screw threads of the vertical shaft at one end, and holds a drawing tool at the other end ...