Forging is a metal forming process in which metal undergoes deformation by subjecting it to impact or pressure. The metal being deformed may be heated to an elevated temperature or it may be cold forged. Components such as: crankshafts, camshafts, turbine shafts, automobile parts, train parts, airplane parts, wrenches, pliers, surgical instruments and connecting rods, etc. are usually forged. The process of forging gives the components high strength, uniform grain structure and since they are near the final shape of the finished component, they also require less machining.
There are various types of forging methods that are common in the industrial world such as: Smith forging, drop forging, machine forging, open die forgings, closed die forgings, and press forging. There are also many types of forging equipment that are used in the process such as: pneumatic and hydraulic hammers, drop hammers, board drop hammers, steam drop hammers, gravity drop hammers, and forging presses, etc.
The billet, which is the metal component that is to be forged, is placed on the table with half of the die. The other half of the die is fitted to a hammer and the hammer is repeatedly dropped on the billet with high pressure, thus deforming the metal until it adopts the deformed shape. You may also use a press to pound and squeeze the metal.
The metal can be heated, but not melted, during the process of forging. However, in cold forging there is no heat applied to the metal. In this method the metal is shaped and molded by pressure alone. Cold forging is generally used for carbon and steel alloys to manufacture smaller parts
The billet can be made of various types of material such as steel, copper, brass, titanium, and aluminum, etc. Though the production rates are relatively slow, this is a mass production technique and the process has been around since biblical times when blacksmiths forged swords and ploughshares on their primitive anvils. The skill of the person who is doing the forging or operating the equipment will have a great deal to do with the overall quality of the finished forgings.