Rolling:
Rolling is a process where the metal is compressed between two rotating rolls for reducing its cross sectional area. This is one of the most widely use of all the metal working processes. Because of its higher productivity and low cost. Rolling would be able to produce components having cross sectional through out its length. May shape such as itl and channel section are possible , but not very complex shapes.
Rolling is normally a hot working process unless specifically mensions as cold working. The metal is taken into rolls by friction and subsequently compressed to obtain the final shape.
The thickness of the metal that can down into rolls depends on the roughness of the roll surface. Rougher rolls would be able to achive greator reduction than smoother rolls. The reduction that would be achieve with a given set of roll is designed as the angle of the bite. cold rolling is done bellow the recrystallization temperature of the metal , hot rolling is done when the metal pieces at uniform working temperature.