By mechanically deforming the heated
metal under tightly controlled conditions, forging produces
predictable and uniform grain size and flow characteristics.
Forging stock is also typically pre-worked to refine the
dendritic structure of the ingot and remove defects or porosity.
These qualities translate into superior metallurgical and
mechanical qualities, and deliver increased directional
strength in the final part.
of continuous grain flow of custom forged contoured
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
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.
Grain Flow Comparison
Directional alignment through
the forging process has been deliberately oriented
in a direction requiring maximum strength. This also
yields ductility and resistance to impact and fatigue.
Unidirectional grain flow has
been cut when changing contour, exposing grain ends.
This renders the material more liable to fatigue and
more sensitive to stress corrosion cracking.
No grain flow or directional
strength is achieved through the casting process.
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.
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.
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.
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
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