What is Forging ?
Forging is a process of manufacturing materials from the raw materials. In brief, we can describe forging as a process in which raw materials are heated and molded to a desired shape, which is obtained when cooled. Even a knife is forged from raw material by heating it and molding it. In other words, it is the shaping of the raw metal to desired shape with the help of the repeated heating and repeating hammerings by exerting compressive loads. Power hammer is mostly used for all the forging processes. The type of hammer changes as per the sensitivity and the type of metal material used. Forging is also applied to samurai swords. A metal is taken and is heated continuously with repeated hammerings. The main aim is to make the sword strong. With more and more compressive force, the strength of the material will also be increased.
Forging came into existence and wide spread only from the time when the industrial revolution took place. Forgings have been used for many applications like kitchen ware, weapons, jewellery and many more.
Types of Forging processes –
Impression Die Forging –
The name itself consists of impression die and the process involved is also the same. The application we need to make is first made into a metal die. The shell must be made with the material in such a way that, what ever may be the heat and pressure, it must resist. Then the output material is poured into the shell and closed very tightly such that both the shells are made together to form a complete shape of the output product. A small hole may be used which helps to push the material in the shell to come close to each other and without any air bubbles. Many 3-d shapes can be produced with ease and the weight of the output product may be very high up to 50,000 tons.
Cold Forging –
Cold forging is also the same process as altering or deformation of the metal into a desired shape but is usually done under re crystallization point. Cold forging is generally preferred by small scale industries as it is very cheap. It is usually preferred when the metal is a soft metal like aluminum. The final product requires very low finishing work as the product obtained is very accurate. The product obtained from the cold forging may be heated to strengthen the piece known as Tempering.
Open Die Forging –
Open Die Forging is the process where the product is obtained when the work piece keeps on moving. Larger parts that are not able to use hot forging process is brought to open die forging process. This is named as open die forging as the metal does not get confined into the space but just resides between the two flat faced dies.
Seamless Rolled Ring Forging –
Seamless Rolled Ring Forging is used when the ring like structure is desired from the work piece. This resembles a donut shape and can be easily obtained by rolling and squeezing process. The work piece is kept rigid and the tool is made to roll in to make a donut.
These are the different types of forging processes.