Difference Between Open Die and Closed Die Forging

Published: 1 Dec 2025

In this article, we will discuss the difference between open die and closed die forging. Forging is one of the oldest and most reliable ways to shape metal, and it is widely used in industries like automotive, aerospace, railways, and heavy machinery. Both open die and closed die forging work by applying heat and pressure, but they differ in technique, precision, and applications. By understanding these differences, you can choose the right forging method for your specific needs.

	Open Die Forging	Closed Die Forging
Process	Metal is compressed between flat or simple dies. The workpiece is not fully enclosed, allowing the operator to manipulate it manually or with machinery.	Metal is compressed inside dies that fully enclose the workpiece. The metal flows to fill the die cavity, creating precise shapes.
Shape Complexity	Best suited for simple shapes like rods, discs, bars, shafts, or cylinders.	Ideal for complex shapes like gears, bolts, flanges, automotive, and aerospace parts.
Production Volume	Works well for low to medium production volumes, especially for large or custom components.	Perfect for high-volume production because of their repeatable precision and efficiency.
Tooling Cost	Low cost as simple dies, hammers, or presses are used.	High cost due to custom-shaped dies and advanced tooling requirements.
Precision	Moderate finishing or machining is often needed to achieve exact dimensions.	High-quality parts are produced accurately and usually require minimal finishing.
Mechanical Properties	Improves material properties like toughness, ductility, and fatigue resistance through controlled deformation.	Provides uniform material properties, enabling consistent performance in mass production.
Applications	Shafts, rollers, discs, rings, cylinders, and large industrial components.	Gears, bolts, flanges, automotive and aerospace components, and industrial tools.
Advantages	Highly flexible, improves mechanical properties, handles large workpieces, and reduces material waste.	Offers high-dimensional accuracy, repeatable quality, and efficiency for complex shapes and large production runs.
Disadvantages	Slower process, less precise, requires skilled operators, and often needs additional machining.	High initial tooling cost, less flexible for design changes, mostly suited for small to medium parts.

Conclusion

In conclusion, in this article, we covered the difference between open die and closed die forging in detail. Open die forging is excellent for large, flexible, and custom parts, while closed die forging is ideal for high-precision, high-volume, and complex components. We hope you find this information useful. If it helped, share it with your friends who might want to understand which forging method fits their projects best.