De Olifant, Burdaard Each revolution of the screw lifts of water. The drive to the Archimedes' screw that pumps water into the polder is from a 38-cog gear wheel meshing with the "great spur wheel". This drives a 25 stave gear wheel which drives a "wallower" (30 cogs). The "wallower" drives a gear wheel with 31 cogs. This drives a cast iron gear wheel with 48 teeth. This drives the Archimedes' screw via a cast iron gear wheel with 60 cogs on the axle of the Archimedes' screw. This Archimedes' screw has an axle diameter of and is diameter overall. It is inclined
Screw wire or rod is then cut to the proper length for the type of screw being made; this workpiece is known as a "blank". It is then cold headed, which is a cold working process. Heading produces the "head" of the screw. The shape of the die in the machine dictates what features are pressed into the screw head; for example a flat head screw uses a flat die. For more complicated shapes two heading processes are required to get all of the features into the screw head. This production method is used because heading has a very high production