Forging involves the application of force to metal to produce dimensional change. In the past, blacksmiths manually pounded and hammered metal parts into desired shapes. Today, this process most usually occurs within highly automated production environments.
Types of Forging
In general, during forging, a metal parts producer applies force to compress metal into a desired dimensional configuration. Manufacturers may conduct one (or more) types of forging: cold forging, warm forging, and hot forging. Temperatures vary based on the metals involved:
Cold Forging (Room Temperature): Manufacturers compress metal at room temperatures in order to perform cold forging. Generally accomplished by machines today, this type of forging requires the use of very strong metal dies in order to deform and compress metal into desired shapes. Soft metals respond especially well to cold forging.
Warm Forging (typically 300 to 1570 degrees Fahrenheit): Forging occurs above room temperature, but not at a point so high that the metallic raw materials become molten. Warm forging offers advantages for manufacturers who prefer to manipulate and compress metal without the application of extremely high temperatures.
Hot Forging (typically 2010 degrees Fahrenheit and above): This type of forging occurs at extremely high temperatures. It will change the internal structure of metals through compression, resulting in the generation of stronger work pieces characterized by homogeneous grain structures.
The Cold Forging Process
Today, cold forging has risen in popularity. It offers a particularly effective way to work with aluminum. Metal parts manufacturers frequently rely upon specific "cold forming" processes.
During cold forging, a manufacturer pounds and compresses metal to produce dimensional changes at room temperature. Currently, most cold forging occurs in highly automated mass production environments. This process offers an especially useful way to change the shape of aluminum and malleable metals, such as copper.
The process of "cold forming" (also known as "cold working") refers to working with metal to shape it at room temperatures, sometimes by means of hammering or pounding mechanically. During cold forging, a manufacturer will typically pound a work piece in order to compress it into desired dimensions. For instance, companies often use hammers, power hammers, or dies to accomplish this objective.
Three popular metal forming processes have gained popularity worldwide: forward extrusion, backward extrusion, and heading (or "upsetting"). Automated machinery enables steel mills to utilize these technologies during mass production at high temperatures:
Forward Extrusion: Hot metal flows through a die formed in a desired cross section. Widely popular in industrial settings, this process helps produce long solid extensions.
Backward Extrusion: Ram force propels a solid die through stationary hot metal, permitting the generation of hollow components, such as metal pipes.
Heading/Upsetting: A punch laterally compresses hot metal positioned horizontally within a strong metal die.
Manufacturers have taken these three basic approaches and applied them to cold forming settings, also. While cold metal billets as a raw material won't "flow", of course, ram force may propel them in a desired direction vis-à-vis an extrusion die. Used in conjunction with strong cold forging or warm forging dies, this powerful technology helps generate a variety of useful small metal components.
Cold Forging: Materials And Applications
Consider these common materials and applications for cold (and warm) forging.
Cold forged parts have found some industrial applications. Today, manufacturers sometimes use cold forging to create jewelry settings using gold alloys. Yet this technology also helps generate light weight industrial parts, also. Aluminum especially frequently serves as a cold (or warm) forging raw material. Today, metals used for cold or warm forging include copper, bronze, aluminum, tin, and, in rare cases, reportedly some steel alloy components.
Cold forging helps generate small metal parts (usually under 10 pounds in weight). Today, companies use cold forging to create nails, pins, auto suspension components, hand tools, and some common kitchenware items. Cold forging holds particular utility for the jewelry, automotive, construction and consumer goods sectors.
Advantages of Cold Forging
Cold forging provides a number of important advantages for manufacturers.
- This process does not necessitate the use of high temperatures. As the name implies, cold forging occurs at room temperature. Companies don't need to invest in blast furnaces, industrial furnaces or other hot metal processing equipment to perform this form of manufacturing.
- Since cold forging today typically involves the use of automated machinery, it generates uniform parts more quickly than some other manufacturing technologies. The use of this process appeals to companies maintaining high volume production facilities. They can conduct cold forging on an ongoing basis without extended downtimes.
- Parts generated with the assistance of computerized cold forging machinery display a high level of duplicability. Manufacturers reproduce these components reliably when they maintain necessary product specifications on file. This situation contributes to the ease of generating uniform replacement parts.
- The strong metal dies used for cold forging tend to last for extended periods of time. Although they eventually wear out, they will tolerate repeated use. The long die lifespan contributes to the efficiency of cold forging.
- The capability to mass produce cold forged parts sometimes contributes to a reduction in per unit pricing. This situation enhances the market competitiveness of products generated using this technology in certain situations. Manufacturers may discover marketing advantages by utilizing this comparatively cost-effective technology.
- Cold forged parts typically require minimal finishing. Since production occurs at room temperature, the manufacturer can handle and manipulate work pieces readily. The use of cold forging in some cases eliminates expensive finishing steps.