What is the Difference Between Open Die and Closed Die Forgings?

Both open die and closed die forging processes provide significant beneficial qualities for a wide range of applications. However, when it comes to your specific part requirements, one method may be more appropriate than the other. Since they consist of different functionalities and physical parameters, open and closed die forging processes are not interchangeable. The differences between the closed die and open die forging processes are explained and fleshed out below.

Open Die Forging

As its name suggests, the open die metal forging process is achieved within a relaxed environment free of encasing devices. The metal workpiece is altered through “hammer” or “stamp” movements until the desired shape is achieved. Advanced open die forging can also produce complex shapes in addition to simpler shaped parts.

Open Die Forging Advantages

Within the open die forging process, metal parts are heated at temperatures ranging from 1900°F to 2250°F and gradually shaped into the desired configuration through the skillful hammering or pressing of the workpiece. Some of the most significant benefits associated with open die forging include:

  • Improved fatigue resistance
  • Continuous grain flow
  • Longer part life
  • Increased strength
  • Less chance of voids
  • Finer grain size

Closed Die Forging

Also referred to as impression die forging, closed die forging uses a closed, high-pressure environment to fill an enclosed die. The forging metal is placed between multiple dies within the open die forging process that do not entirely retain the metal. The dimensions will be changed by hammering and stamping the metal through a series of movements until the final measurements are achieved.

Closed Die Forging Advantages

Closed-die forging is one of the most used methods for forging steel parts. This process works with the metal’s internal grain structure and can produce more potent longer-lasting products. The benefits associated with closed die forging include:

  • Dimensions with tighter tolerances and various shapes can be achieved
  • More precise, consistent impressions
  • Ability to reproduce nearly any shape or size
  • Better surface finish and superior mechanical properties
  • Reduced or no machining
  • Cost-effective for large production runs

Choosing Between Open Die and Closed Die Forging for Your Project Needs

Multiple factors should be considered before choosing which forging process is best for your project. One of the most significant considerations that should be weighed when deciding between open and closed die forging processes is that open die workpieces must be continuously moved throughout the forging process.

Conversely, closed die forgings are entirely automated with minimal human interaction. Since less automation is involved within open die forgings, significant cost-saving advantages are associated with this process. However, if increased automation is the goal, then closed die forging would be the best option.

Contact Great Lakes Forge for Expert Closed and Open Die Forging Services

Great Lakes Forge is your trusted provider of premium closed and open die forging services for your metal part and component manufacturing needs. Contact us for more information on our custom forging service options, or give us a call at 800-748-0271, and we’ll help you find the best custom forging options for your project.