Forging is a manufacturing process where metal is pressed, pounded or squeezed under great pressure to produce high-strength parts. Forged aluminum is ideal for applications where performance and safety are critical but a lighter-weight metal is needed for speed or energy efficiency. The forged aluminum wheels on Daytona racecars are a perfect example. There are primarily three types of forging processes: open-die forging, ideal for larger aluminum components; closed-die forging, well-suited for more intricate designs and tighter tolerances; and ring-rolled forging used to create high-strength ring-shaped applications.
- How are forgings producted
Forging--metal shaping by plastic deformation--spans a myriad of equipment and techniques. Knowing the various forging operations and the characteristic metal flow each produces is key to understanding forging design.
- Hammer and Press Forging
Generally, forged components are shaped either by a hammer or press. Forging on the hammer is carried out in a succession of die impressions using repeated blows. The quality of the forging, and the economy and productivity of the hammer process depend upon the tooling and the skill of the operator. The advent of programmable hammers has resulted on less operator dependency and improved process consistency. In a press, the stock is usually hit only once in each die impression, and the design of each impression becomes more important while operator skill is less critical.
- Forgings The Process
Open Die Forging Open die forging with hammers and presses is a modern-day extension of the pre-industrial metalsmith working with a hammer at his anvil.
In open die forging, the workpiece is not completely confined as it is being shaped by the dies. The open die process is commonly associated with large parts such as shafts, sleeves and disks, but part weights can range from 5 to 500,000 lb.
Most open die forgings are produced on flat dies. Round swaging dies and V dies also are used in pairs or with a flat die.
- Operations performed on open die presses include:
- Drawing out or reducing the cross-section of an ingot or billet to lengthen it.
- Upsetting or reducing the length of an ingot or billet to a larger diameter.
- Upsetting, drawing out, and piercing--processes sometimes combined with forging over a mandrel for forging rough-contoured rings.