Open Die Forging

Open Die Forging Process

Open die forging is the process, which involves the shaping of any hot metal parts. This is done with a top die that is attached to a ram and the bottom die gets attached to a hammer or bolster. Metal parts need to have appropriate temperatures, somewhere in the range of 500°F to 2400°F. These can then be shaped into the desired configuration with the help of skilful hammering or even by applying pressure to the workpiece. Sometimes, open die forging is also referred to as free forging or impression die forging. The metal is constantly hammered and stamped to finally achieve a certain set of dimensions within the open die forging process.

Benefits of Open Die Forging

Open die forging helps in reducing the chances of voids. It is also known to help improvise fatigue resistance. With the ability to provide continued grain flow, it can also help in generating finer grain size. It provides greater strength and improved microstructure. Advanced open die forging can also produce complex shapes in addition to simpler shaped parts. Steel and related alloys are generally subjected to open die forging. A lot of other metals like copper, nickel etc. can also be shaped using open die forging.

Open Die Forging vs. Closed Die Forging

Closed die forging, also known as an impression, generally confines the metal in dies. In contrast, open die forging does not confine or restrain the metal in dies. Open die forgings are generally produced on flat dies. This process is meant for larger, simple-shaped parts like blanks, rings, bars, spindles etc. This is also considered to be the best option for custom-designed metal parts.

The biggest challenge in the open die forging process is that the workpiece has to be continuously moved as it is worked upon. It requires some complex mechanical controls and even skilled human operators at times. Closed die forging, in contrast, can be entirely automated with minimal human involvement and a much simpler process in all. However, Open die forging can result in some valuable cost savings and even limited material wastage in most cases, which is why it is highly preferred.