“The Archimedes' screw consists of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe.” (Ref.http://en.wikipedia.org/wiki/Archimedes%27_screw ; Aug. 22, 2012)
The Archimedes' screw consists of a screw (a helical surface surrounding a central cylindrical shaft) inside a hollow pipe. “A screw thread (plate 12B-D), often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread. A screw thread is the essential feature of the screw as a simple machine and also as a fastener. More screw threads are produced each year than any other machine element.[1]” (Ref.http://en.wikipedia.org/wiki/Screw_thread ; Aug. 22, 2012)
Because of its unique of screw it is being used in various products for thousands of years. The angle of the thread (‘V’) is standardized as 60 degree. However there is no restriction to any other angle.
