Open Die Forging

Open vs Closed Die Forging

Forging is the process of deforming metal to create a new product. Two different types of forging include both open die and closed die forging.

Open die forging is the process of deforming metal between two dies which are usually flat, the dies don’t fully close the piece being worked on. That’s where the name open die forging comes from.

This process is cost-effective as there is little to no tooling cost and reduced lead time. There are drawbacks however, open die forging isn’t suitable for forming precision parts and machining is required for the part to be accurate.

Closed die forging involves the process of using a die to completely enclose the part. This type of forging requires less machining and provides a better surface finish. Closed die forging is cost-effective for large runs of production and tighter tolerances can be achieved.

The first step of closed die forging is creating a mould which is used to forge the hot metal into its final shape. CAD (Computer-Aided Design) is used to design a 3D drawing which is then used to create a plastic model. The next step involves creating the die itself which is made from hardened tool steel and allows many forgings to be created from the same mould.

There are downsides to this however, closed die forging isn’t economical for short production runs due to the high cost of die production and the machinery used is generally more expensive.

Both types of forging have their advantages and disadvantages, open die forging, for example, is ideal for creating simple shapes with high strength at a relatively low cost. If your product is more complex and requires a larger production run, then closed die forging is for you. Due to its high setup costs, it is not suitable for one-off forgings. For small critical parts, closed die forging is preferred for its accuracy and therefore the safety it offers.