Drop Forging
Drop forging is a metal shaping process where a heated workpiece is placed between two dies and deformed by the repeated impact of a hammer or ram that is dropped onto it. The force of the drop causes the metal to flow and fill the contours of the die, forming the desired shape.
There are two main types of drop forging:
- Open-die forging, where the metal is struck between flat or simple-shaped dies, allowing it to flow outward freely.
- Closed-die forging (also called impression-die forging), where the metal is confined within a die cavity that contains the exact shape of the final part.
Drop forging is typically used for producing strong, durable components such as crankshafts, connecting rods, and hand tools. The process enhances the mechanical properties of the metal by aligning its grain structure, resulting in increased strength and fatigue resistance.
Forging is basically involves plastic deformation of material between two dies to achieve desired configuration.
Machines used : Drop Type Hammer Forging, Power Press, etc.
Drop Hammer
Forging Press
Open Die Forging
Closed Die Forging
Press Forging :
Press forging is a metal forming process that uses a slow, continuous application of pressure to shape a workpiece. Unlike impact-based methods such as drop forging, press forging deforms the entire volume of metal uniformly and gradually. The process can be performed hot or cold, depending on the material and desired properties.
In press forging, a hydraulic or mechanical press forces the metal into a die cavity, producing parts with improved mechanical properties, closer dimensional tolerances, and better surface finishes. This method is ideal for creating large, intricate, or high-strength components, and is commonly used in the automotive, aerospace, and heavy machinery industries.
Machines used : Forging Press, Power Press, etc.
Press Forging
Cold Forging :
Cold forging involves shaping and processing metals at room temperature or slightly above it. It includes a range of techniques such as drawing, heading, coining, punching, and thread rolling. During cold forging, the metal is typically worked at around 30% of its recrystallization temperature, making it especially effective for softer metals like aluminum and copper. This process offers several advantages, including improved surface finish, greater dimensional accuracy, reduced need for post-processing, and lower production costs.
Machines used : Cold forging press machine
Cold Forging
Roll Forging :
Roll forging is a metal forming process that involves shaping heated metal by passing it between two rotating, opposing rolls. The rolls are engraved with specific geometric patterns that define the part’s final shape and dimensions. As the workpiece moves through the rolls, they rotate slightly to gradually deform and shape it. These patterns typically cover between one-quarter and three-quarters of the roll surfaces. The grooves in the rolls produce a workpiece with a variable cross-section, which can be further refined through secondary finishing processes.
Machines used : Roll Forging Machine (or Roll Forging Mill)
Roll Forging
Ring Rolling Forging :
In Ring Rolling forging, the process begins by shaping a metal workpiece into a donut or oval form by removing its center. The ring-shaped blank is then heated to forging temperature and positioned between three types of rolls: a driver roll, an idler roll, and axial rolls, all of which rotate in coordination.
The idler roll supports the workpiece and gradually moves it against the driver roll, which compresses the ring radially—expanding its outer diameter while reducing wall thickness. Meanwhile, the axial rolls control the ring’s height (or width), ensuring uniform shape as the piece rotates.
This method produces seamless, high-strength oval or circular rings, commonly used in critical applications such as gears, valves, bearings, and clutches.
Key benefits of ring rolling forging include:
- Enhanced component strength through grain flow alignment
- Minimal need for post-forging machining
- Excellent material utilization and structural integrity
- Compatibility with a broad range of metals, including steel, titanium, aluminum, and alloys
The process is especially valued in industries requiring high-performance, fatigue-resistant parts.
Machines used : Ring Rolling Machine
Ring Rolling Forging
Upset Forging :
Upset forging, also known as heading, is a forming process that can be carried out either hot or cold. It involves increasing the cross-sectional area of the end of a workpiece by applying compressive force along its axis. This technique is typically used with horizontally positioned bar stock and is commonly employed in the production of fasteners such as nails, screws, bolts, and nuts.
The shaping is usually performed using a punch, a die, or a combination of both, depending on the complexity and precision required for the final part.
In the cold forging example shown below, the process begins by securing a rod in a lower die. The upper die then repeatedly strikes the rod, gradually deforming and shaping the material into the desired form through a series of controlled blows.
Machines used : Upset Forging Machine (or Heading Machine)
Upset Forging
Isothermal Forging :
Isothermal forging is a specialized process that ensures the workpiece maintains a consistent temperature throughout forging. For metals and alloys with low forgeability at higher temperatures, this approach addresses the challenge by keeping the workpiece at its optimal temperature during the entire process. This is accomplished by heating the die to a temperature that is either equal to or slightly lower than that of the workpiece. By doing so, isothermal forging eliminates temperature gradients between the workpiece and die, leading to improved characteristics in the final part.
Machines used : Isothermal Forging Press
Automatic Hot Forging :
Automatic hot forging is a metal forming process in which heated billets are shaped into desired components using fully automated machinery. In this process, steel bars are fed into a forging machine, where they are rapidly heated and then formed using forging presses and other automated systems. This method enables high production rates and consistent quality in hot forged products.
Swaging Forging :
Swaging, also referred to as rotary swaging or radial forging, is a metal forming technique used to modify the dimensions of a workpiece by compressing it with dies. This process is typically employed to reduce the diameter of rods or tubes and can be carried out either hot or cold. Swaging is often categorized as a specialized form of forging due to its use of compressive forces to shape metal.
If there are any additional types of forging that we may have missed, we welcome your input. Please feel free to leave a comment to help us improve and expand our understanding. Your feedback is valuable and appreciated..
