forging

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FORGING

Presented by \u2013 Rajatabh

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As with the cultural history of man, the history

of metals springs from the land between the

Tigris and the Euphrates,

once called Mesopotamia. The earliest signs of

metalworking date back to about 4500 B.C.

The inhabitants of this fertile valley were the

Sumerians. These people, a mixture of many

ethnic backgrounds, were the true founders of

metallurgy as we know it today.

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\ue000Forging as an art form started with the desire

to produce decorative objects from precious metals. Today, forging is a major world-wide

industry that has signiﬁcantly contributed to the development of man.

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Post Medieval (1600 )

Post Medieval (1600 ) True use of deliberate cast iron does not develop untill the introduction of coal as a smelting fuel in the very late 1500's on the continent and into the early 1600's in England.

By the time of Jamestown Virginia (1610 +) there are starting to be small pots available. These were

extremely expensive and limited to the upper class. Think of the 'witches caldron' shape with three legs, maybe holding one or two gallons.

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Settlement Era (1700 )

GENERAL use of cast

iron-Cast iron becomes easier to produce and control. It still is expensive, but prices and availability have dropped to the point that many families can aﬀord a SINGLE pot or pan.

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Industrial Age (1820 )

EXTENSIVE use of cast

iron-Cast iron cookware will not become both cheap and widespread until the introduction of steam powered technologies. The Victorian period has the largest use of cast iron for all kinds of objects, from personal goods to architectureal.

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19th and 20th CENTURY

Forging industry saw a new revolution in the world with wide use in many of the metalware industry.

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Cold forging:

These include bending, cold drawing, cold heading,

coining extrusion (forward or backward), punching,

thread rolling and others.

Hot forging:

plastically deforming an alloy at a temperature

above its recrystallization point, i.e., high enough

to avoid strain hardening.

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Open Die Forgings / Hand Forgings:

Made with repeated blows in an open die,

The operator manipulates the workpiece in the die.

Impression Die Forgings / Precision

Forgings:

Are further reﬁnements of the blocker

forgings

.

The ﬁnished part more closely resembles

the die impression.

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Anvil

serves as a work bench to the , where the

metal to be beaten is placed.

made of cast or wrought iron with a tool steel face welded on

b lac ksmith

The ﬂat top has two holes; the wider is called the hardy hole, where the square shank of the hardy ﬁts.

The smaller hole is called the punch hole, used as clearance when punching holes in hot metal

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ADVANTAGE

• Uniformity of qualities for

parts subject to high stress and loads.

• No weight loss. • Close tolerance.

• Less machining or no

machining in some cases.

• Smooth surface.

• High speed of production. • Incorporation in welded

structures, i.e., what can be welded easily.

DISADVANTAGES

• High tool cost.

• High tool maintenance. • Limitation in size and

shape.

ADVANTAGES AND DISADVANTAGES OF

FORGING

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ADVANTAGES

• Decrease in yield strength,

therefore it is easier to work and takes less energy (force).

• Increase in ductility.

• Elevated temperatures

increase diﬀusion which can remove or reduce chemical inhomogeneities.

• Pores may reduce in size or

close completely during deformation.

DISADVANTAGES

• Undesirable reactions between the

metal and the surrounding atmosphere (scaling, or rapid oxidation, of the work piece).

• Less precise tolerances due to

thermal contraction and warping from uneven cooling.

• Grain structure may vary

throughout the metal for various reasons.

• Requires a heating unit of some

kind such as a gas or diesel furnace or an induction heater, which can be very expensive.

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ADVANTAGES

• No heating required.

• Better surface ﬁnish.

• Better reproducibility and

interchangeability.

• Directional properties can be

imparted into the metal.

• Contamination problems are

minimized.

DISADVANTAGES

• Higher forces are required.

• Heavier and more powerful equipment

and stronger tooling are required.

• Metal is less ductile.

• Metal surfaces must be clean and

scale-free.

• Intermediate anneals may be required to

compensate for loss of ductility that accompanies strain hardening.

• The imparted directional properties may

be detrimental.

• Undesirable residual stress may be

produced.

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Forging applications

FORGING refers to the production of those parts which must be heated in a closed furnace .

The portion of work in which forging is done is termed as the forge and the work is mainly performed by the means of

hammers, machines and presses.

Forging processes are among the most important

manufacturing techniques since its used in small tools ,rail road equipment ,automobile ,aviation sector ,as well as home and

other accessories .

Knives Punching

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Forging can be used in home accessories like lamps, kitchenware and screws .

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Upset or machine forging

Forging of ring and rod types with all kinds of heads such as bolts,nuts ,washers and collars ,gears etc that can be produced

conveniently in forging machine .

Another application can be in making gears of various sizes used in machines .

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Press forging

Press forging is done in presses rather than with

hammers .the action is relatively slow squeezing instead of delivering heavy blows and penetrates deeply because it gives metal time to ﬂow .

Towel holders. A hook is there so that the towel can be hung

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Drop forging

Drop forging is a metal shaping process in which a heated workpiece is formed by rapid closing of a punch and die forcing the workpiece to conform to a die cavity.

A workpiece may be forged by a series of punch and die operations (or by several cavities in the same die) to

gradually change its shape. Drop forging is also called impression die or closed die forging, or rot forging.

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Press Forging

Press Forging is a process whereby slow pressure is continuously applied to the area to be shaped. The

pressure extends through the material which can be either hot or cold. Cold press forging is primarily used on thin

materials, while hot press

forging is preferred for larger work such as parts for trains and heavy machinery

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The pressure necessary to form to steel at forging

temperature varies from about 3000psi(pounds per square inch) 27,000psi (20 to 190MPa). These pressure are based on the cross-section area of the forging when measured across the surface of the die at the parting line

Press capacity is expressed as P= F/A 2000

P= Pressure required,psi F= Pressure capacity, tons

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Process

Press forging is done in presses rather than with hammers .The action is relatively slow squeezing of delivering heavy blows and penetrates deeply because it gives the metal time to ﬂow .Dies may have less drafts, and the forging comes nearer to the

desired sizes . Pressed forgings are shaped at each impression with a single smooth stroke and they stick to the die impression more rigidly . Unless some provision is ,therefore , made the

escape of air and excess die lubricant may be diﬀicult .Thus press forging dies require a mechanical means for ejecting the forging are venting for escape of air and lubricant.

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Hydraulic press

Hydraulic press for closed die forging has the same principle as that of a press for smith or ﬂat die forging except the construction of the dies

Moreover , they form an integral part of the frame to maintain accurate alignment of the dies

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Mechanical forging press

Mechanical forging presses of the cranks type have found wide application in forging practice

The operative units of the press are powered from motor mounted on the press frame. By means of the v-belt drive, power is transmitted from pulley to ﬂywheel mounted on the auxiliary shaft .

The is stopped by the auxiliary brake which is automatically engaged when the motor is switched oﬀ.

Used for the production of rivets, screws ,and nuts where a high operating speed is desired .

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Material Used

Iron, Copper, Aluminium

Carbon steels, Alloy steels, Stainless steel

Cast aluminum alloys, Wrought aluminum alloys Cast copper alloys, Wrought copper alloys

Titanium alloys, Magnesium alloys Polyamides, Polycarbonates

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ADVANTAGES

Press forging can be used to perform all types of forging, including open-die and impression-die forging.

Impression-die press forging usually requires less draft than drop forging and has better dimensional accuracy.

Also, press forgings can often be done in one closing of the dies, allowing for easy automation

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Press Forging Beryllium

Copper Billet Press, Puching Press. Forging

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Upset Forging

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What is Upset Forging?

Performed on bar stock, upset forging decreases the length of

the stock and increases its cross-section.

High pressures deform the metal and force material into a

designated area of the bar.

The material is shaped into tools such as bolts, pinions,drill

rods, and other objects where high strength is a necessity.

Upset forging reﬁnes the mechanical properties by

re-orienting the grain ﬂow to the shape of the tool.

orienting the grain ﬂow to the shape of the tool.

The result is a component which is inherently stronger than

that which has been cast, welded, or machined.

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Upset forging is a metal shaping process in which a heated

workpiece of uniform thickness is gripped between split

female dies while a heading die is forced against the

workpiece, deforming and enlarging the need of the

workpiece.

A sequence of die cavities may be used to control the

workpiece geometry gradually until it achieves its ﬁnal shape.

This is a rapid "cold forming" process.

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Process Characteristics

Increases the diameter of the end of the central portion of a

workpiece by compressing its length.

Complex parts are usually formed gradually in a sequence of

separate die cavities.

May produce diameters up to three times the original

diameter.

Impressions may be in the punch die, gripping die, or both.

Impressions may be in the punch die, gripping die, or both. Usually requires no trimming

Usually requires no trimming

May be performed cold on ductile materials. May be performed cold on ductile materials.

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Materials Used for Upset Forging

Philadelphia Forgings supplies a wide variety of forgings.

Our forgings are produced from materials such as aluminum

alloy, carbon steel, stainless steel, nickel alloys, Inconel,

titanium alloy, superalloys, and many more.

To see the complete listing of materials or to learn more about

their metallurgical properties, please visit our

their metallurgical properties, please visit our forgingforging materials

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Beneﬁts of Upset Forgings

The act of upset forging breaks up the cast structure of the

material, aligns the grain ﬂow, and eliminates weaknesses in

the material, such as microshrinkage, gas porosity, and areas

of low density.

Rods, pinions, bolts, and other components created through

upset forging exhibit better levels of strength and soundness.

Upset forged components resist deformation and breakage

during use.

These characteristics make them ideal for applications where

high performance is a must.

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