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What is Forging?
Forging is manufacturing process where metal is pressed,
pounded or
squeezed under great pressure into high strength parts known as
forgings. The process is normally (but not always) performed hot by
preheating the metal to a desired temperature before it is worked. It
is important to note that the forging process is entirely different
from the casting (or foundry) process, as metal used to make forged
parts is never melted and poured (as in the casting process). Discuss
your requirements for custom forgings with OEM Sales before making that
critical decision.
Contact us to discuss your concerns. What metals are forged?
Just about any metal can be forged. However, some of the most common metals include: carbon, alloy and stainless steels; very hard tool steels; aluminum; titanium; brass and copper; and high-temperature alloys which contain cobalt, nickel or molybdenum. Each metal has distinct strength or weight characteristics that best apply to specific parts as determined by the customer.
What are the types of forging processes? There are basically four methods (or processes) to make a forged part.
Impression Die Forging Impression
die forging pounds or presses metal between two dies (called tooling)
that contain a precut profile of the desired part. Parts from a few
ounces to 60,000 lbs. can be made using this process. Some of the
smaller parts are actually forged cold.
Cold Forging Most forging is done as hot work, at temperatures up to 2300 degrees F; however, a variation of impression die forging is cold forging. Cold forging encompasses many processes -- bending, cold drawing, cold heading, coining, extrusions and more, to yield a diverse range of part shapes. The temperature of metals being cold forged may range from room temperature to several hundred degrees. Open Die Forging Open die forging is performed between flat dies with no precut profiles is the dies. Movement of the work piece is the key to this method. Larger parts over 200,000 lbs. and 80 feet in length can be hammered or pressed into shape this way.
Seamless Rolled Ring Forging Seamless rolled ring forging is typically performed by
punching a hole
in a thick, round piece of metal (creating a donut shape), and then
rolling and squeezing (or in some cases, pounding) the donut into a
thin ring. Ring diameters can be anywhere from a few inches to 30 feet.
Forging Advantages Part Integrity
2. Structural Strength
Forging also provides a degree of structural integrity that is unmatched by other metalworking processes. Forging eliminates internal voids and gas pockets that can weaken metal parts. By dispersing segregation of alloys or nonmetallics, forging provides superior chemical uniformity. Predictable structural integrity reduces part inspection requirements, simplifies heat treating and machining, and ensures optimum part performance under field-load conditions. 3. Impact Strength Parts can also be forged to meet virtually any stress, load or impact requirement. Proper orientation of grain flow assures maximum impact strength and fatigue resistance. The high-strength properties of the forging process can be used to reduce sectional thickness and overall weight without compromising final part integrity. Part Flexibility
1. Variety of Sizes
Limited only to the largest ingot that can be cast, open die forged part weights can run from a single pound to over 400,000 pounds. In addition to commonly purchased open die parts, forgings are often specified for their soundness in place of rolled bars or castings, or for those parts that are too large to produce by any other metalworking method. 2. Variety of Shapes Shape design is just as versatile, ranging from simple bar, shaft and ring configurations to specialized shapes. These include multiple O.D./I.D. hollows, single and double hubs that approach closed die configurations, and unique, custom shapes produced by combining forging with secondary processes such as torch cutting, sawing and machining. Shape designs are often limited only by the creative skills and imagination of the forging supplier. 3. Metallurgical Spectrum Forgings can be produced from literally all ferrous and non-ferrous metals. The forging process itself can be adjusted-through the selection of alloys, temperatures, working methods and post-forming techniques-to yield virtually any desired metallurgical property. 4. Quantity and Prototype Options Virtually all open die and rolled ring forgings are custom made one at a time, providing the option to purchase one, a dozen or hundreds of parts as needed. An added benefit is the ability to offer open die prototypes in single piece or low volume quantities. No better way exists to test initial closed die forging designs, because open die forging imparts similar grain flow orientation, deformation, and other beneficial characteristics. In addition, the high costs and long lead times associated with closed die tooling and set-ups are eliminated. Economic Advantages Cost Reduction
For more information, please contact us.
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