ing Shop 

Forging is the process by which metal is heated and is shaped by plastic deformation by suitably applying compressive force. Usually the compressive force is in the form of hammer blows using a power hammer or a press.

The Forging Process is the forming of linear bars of metal into desired 3-dimensional shapes. This metal forming is done by way of applying a very high amount of pressure on the steel bars. The main equipment used for this purpose is a forging press and the forging dies made from special alloy steel with a very high tensile strength.

The forging process can be divided into the following operational stages:

a) Die Design & Development: After the receipt of the finished part drawings from the customers, the engineering teams at the forging facilities develop a forging drawing from the finished part drawing. Then they develop a 3-dimensional model for the part to be forged. From this 3-dimensional model, the engineers then create the 3-dimensional models of the forging dies, trimming dies and the coining dies; which comprise a complete set of dies for a particular part. The final process in this stage is the die-sinking operation, wherein the actual shape of the part is replicated on the die-blocks in form of cavities.

b) Inspection Of Dies: The set of dies manufactures is then subjected to a series of tests for verifying the accuracy of the design & shape of the cavities on them. For this purpose, plaster of Paris is poured into the die blocks and is allowed to set. Then the plaster cast is then removed from the die cavity and subjected to dimensional verification by the quality assurance team. Once the quality assurance team is satisfied with the dimensional accuracy, they approve the die set to be issued to the production department for loading on the forging presses.

c) Forging: The set of die blocks thus manufactured is loaded on to the forging press, trimming press and the coining press. Then simultaneously another process involves cutting of steel pieces from straight steel bars known as billets. These billets are then heated to a definite temperature by electrical energy known as induction billet heating. The heating time and the flow of current are regulated to control the billet at a desired temperature. The red-hot billets are given an approximate shape by a process called reduce-rolling. Then these red hot billets are placed in the cavity of the die block in the forging press where the billet under the impact / pressure of the press stroke takes the final desired shape. The red hot forging is then placed onto the next station known as trimming press to remove extra material called flash. The forging is then allowed to cool down. It is inspected for its dimensional accuracy. 

d) Heat Treatment: Once approved for its accuracy, these forgings are then subjected to a process of hardening and/or tempering depending on the hardness requirement of the component. Subjecting the forgings to a controlled heating inside specially designed automatic heating furnaces does this hardening & tempering. This process is required because a lot of stresses develop in the steel because of induction billet heating and forging. These effects of these stresses are removed by proper hardening and tempering in automatic heat treatment systems. 

e) Shot-Blasting: After hardening & tempering, the surface of the forgings is oxidized by scale formation. These scales are then removed by a process called shot blasting. This process involves striking the surface of the forgings by tiny spherical particles of sand and metal to remove the scales. This process of shot blasting also makes the surface of the forging clean and gives it silvery appearance.