It has been suggested that Leonardo Da Vinci invented the first rolling mill, but what exactly is a rolling mill? A rolling mill is a unit in which a metal forming process takes place. During this process various metal materials get passed through a massive pair of rolls, or material handling equipment. The term "rolling" is categorized by the temperature at which the metal gets rolled. Should the temperature of the metal be above that at which it can recrystallize, the process is known as "hot rolling." Conversely, should the temperature used be below its recrystallization temperature, then the process is called "cold rolling".
A rolling mill which uses the "hot rolling" method is capable of processing more gross weight of metal than any other manufacturing process. Rolling mills which use the "cold rolling" method can process the most tonnage from the entire range of cold working processes. There are many types of rolling processes used in rolling mills, including ring rolling, roll bending, roll forming, profile rolling, and controlled rolling.
History of Rolling Mills
A rolling mill can also be known as a reduction mill, or just simply, a mill. Rolling mills have a common construction regardless of which kind of rolling is being performed.
Rolling mills have been in existence since the 1590's for the production of iron strips. The early mills were both small and water-driven. Matthew Boulton came up with an idea in 1781 to use a steam engine to drive a rolling mill and thus the first steam-driven mill was devised. A resourceful designer, Watt, invented an engine with two cylinders and two beams which was to become the envy of other ironmasters at the time; this was the forerunner to many other mills and had other engineers scrambling to compete. James Naysmith, who invented the Steam Hammer in 1838, came up with the idea for reversing engines. This was found to work well, resulting in the standard drive for reversing rolling mills becoming either a two or three crank reversing engine. It was not feasible to use a fly wheel with these engines, ending with the cylinders having to be made large enough to take the maximum load. The engine generally ran well under its power, but was found to be uneconomical. These engines were therefore referred to as "steam eaters".