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10 Facts of Closed Die Forging You Should Know
The closed die forging method, sometimes referred to as the impression-die forging method, is a fabrication process that involves heating metal and then molding it between two dies that completely enclose the workpiece. This approach is commonly employed to create strong parts with tight tolerances.
Common across industries from aerospace and automotive to construction, this process produces metal parts that are strong, accurate, and long-lasting. Steel and aluminium components are mostly produced via closed die forging.
How Closed Die Forging Works?
Closed die forging uses one or more dies with pre-machined cavities. The metal is inserted between the two dies and pressed under high pressure; it then assumes the shape of the die cavities.
The excess plastic, called “flash,” escapes at the edges, and that helps fill the whole die cavity. This initial burst is eventually cut short. This process guarantees precise and consistent results, which is the main reason for its mass-scale manufacturing of complex parts. Here are the top facts of closed die forging.
1. High Strength and Durability of Forged Parts
Parts made with closed die forging have better mechanical properties. The process also refines the metal’s grain structure, improving strength, toughness, and fatigue resistance. The grain flow is compressed and follows the geometry of the part, ensuring no weak points or internal defects.
Example: Many aircraft landing gear components are closed-die forged to survive high loadings and stresses.
2. Precision and Complexity in Part Design
The closed die forging process allows manufacturers to produce extremely precise and complex designs with tight tolerances.
The design of the dies is modernized so that they are produced quickly and with minimum machining required on forging. For their forge parts, some industries need tolerances as tight as ±0.5 mm.
3. Reduced Material Waste Compared to Machining
Some flash is created in the process, but closed die forging results in less waste of the material in comparison with machining processes. This stands in comparison to machining, in which a chunk of material is formed to its final shape through cutting excess away, creating a proportionally massive amount of waste.
Economic Benefit: Cost savings on raw materials and sustainability by reducing scrap.
4. Efficiency
Closed die forging, despite the high initial cost for die creation and design, becomes advantageous and cost-effective at larger production volumes because of the low recurring cost per part.
Facts of Closed Die forging is a highly efficient process, so it is often the go-to method in industries such as automotive and tool manufacturing.
5. Design Considerations
Close die forging depends upon the good designs of the dies. If possible, designers should try to part along a single, flat plane, use adequate draft angles, use generous fillets and radii, and balance different sections to promote good metal flow and minimize defects.
6. Die Costs and Production Volumes
Closed die forging requires precision machining of the dies, so the initial cost to create the dies is relatively high. However, these costs are negligible in large production runs, enabling mass production.
A downside of this method is that it has a high initial cost to make the dies. These dies cannot be made cheaply because they need to be machined and heat-treated very precisely. This applies as the fixed cost is often bearable when producing high quantities of parts, where production runs allow for a decrease in part cost.
7. Material Efficiency
Flash is formed in the process, but closed die forging tends to generate less material waste than machining from solid billets. As a result of this efficiency, it is a cost-effective method for creating larger volumes of components.
8. Design Considerations
Close die forging depends upon the good designs of the dies. If possible, designers should try to part along a single, flat plane, use adequate draft angles, use generous fillets and radii, and balance different sections to promote good metal flow and minimize defects.
9. Lubrication Importance
In forging, lubricants reduce friction and wear, serve as thermal barriers that limit heat transfer from the work piece to the die, and act as parting agents to keep the part from adhering to the dies.
10. Flashless Forging Variation
Flashless forging is a variant of this principle in which the work piece is fully contained within the die cavities and flash is avoided. The facts of closed die forging technique minimize material waste but demand more accurate mold design and lubrication.
Future Trends and Advancements in Closed Die Forging
In recent years, new technologies have been developed that help the forging industry achieve higher efficiency and precision. Some future trends include:
3D printing for die making: Additive manufacturing has been employed to build a large variety of complex die shapes more rapidly and at a lower cost.
Automation and Robotics: Forgings that are loaded by robots increase both the speed of production and worker safety.
AI and Simulation Software: AI-based design and simulation software can optimize die design and minimize production errors.
Conclusion
In a closed die forging, the metal billet is heated and placed in between two dies that have a negative impression of the part you want. The facts of closed die forging is a procedure that emphasizes experience.
Even though the initial die costs may be significantly high, its advantages, including higher mechanical properties, less waste, and higher production rates, have made it one of the most used methods in various industries. New technologies and materials will ensure the future of closed die forging is even more efficient and versatile.