Some important forging process like sizing, coining, embossing and roll forging

3.  Sizing is a operation performed at temperatureSizing is a operation performed at temperature
below the melting point to finish the surface ofbelow the melting point to finish the surface of
work-piece to ensure better dimensionalwork-piece to ensure better dimensional
accuracy and surface finish.accuracy and surface finish.
 It minimize the thickness of the metal.It minimize the thickness of the metal.
 Sizing operation performed in open die.Sizing operation performed in open die.

4.  It is mostlyIt is mostly
used to giveused to give
a forged ora forged or
cast partcast part
betterbetter
dimensionaldimensional
accuracy.accuracy.

5.  When we performed sizing operation on work-When we performed sizing operation on work-
piece the sized surface of the work-piece getspiece the sized surface of the work-piece gets
denser and stronger.denser and stronger.
 Sizing operation pressure is determined by areaSizing operation pressure is determined by area
to be sized.to be sized.
 It is usually performed on semi-finished parts orIt is usually performed on semi-finished parts or
parts that require an accurate surface finish.parts that require an accurate surface finish.

6. It is a special type of closed die forging.It is a special type of closed die forging.
In this process work is completelyIn this process work is completely
confined. Both surfaces of the workconfined. Both surfaces of the work
receive impressions.receive impressions.
It is flashless operation.It is flashless operation.

8.  Coining can be done using a gear drivenCoining can be done using a gear driven
press, mechanical press, or morepress, mechanical press, or more
commonly a hydraulically actuated press.commonly a hydraulically actuated press.
 Coining require higher tonnage pressesCoining require higher tonnage presses
than stamping.than stamping.
 Part produce by coining operation like:Part produce by coining operation like:
coins, medals, badges, buttons.coins, medals, badges, buttons.

11. It is a special type of forging.It is a special type of forging.
This process uses a matched punch andThis process uses a matched punch and
die.die.
It is a open and closed die forging.It is a open and closed die forging.
The material flows in the direction ofThe material flows in the direction of
applied forces.applied forces.

12.  Embossing operation is a commonlyEmbossing operation is a commonly
accomplished with a combination of heat andaccomplished with a combination of heat and
pressure.pressure.
 CharacteristicsCharacteristics
 Embossing operation is a ability to form ductileEmbossing operation is a ability to form ductile
metals.metals.
The ability to produce unlimited patterns,
depending on the dies.

15.  In this process, the bar stock is reduced inIn this process, the bar stock is reduced in
cross-section or undergoes change in cross-cross-section or undergoes change in cross-
section when it is passed through a pair ofsection when it is passed through a pair of
grooved rolls made of die steel. This processgrooved rolls made of die steel. This process
serves as the initial processing step for forgingserves as the initial processing step for forging
of parts such as connecting rod, crank shaft etc.of parts such as connecting rod, crank shaft etc.
Finished products like tapered shafts, leafFinished products like tapered shafts, leaf
springs can also be made.springs can also be made.

16.  In this process the rolls are not completely cylindrical butIn this process the rolls are not completely cylindrical but
are sector shaped to permit the stock to enter between theare sector shaped to permit the stock to enter between the
rolls.rolls.
 These roll segments have one or more sets of grooves toThese roll segments have one or more sets of grooves to
impart a desired shape to the piece being forged.impart a desired shape to the piece being forged.
 When the rolls are in open position, the heated stock isWhen the rolls are in open position, the heated stock is
advanced up to a stop. As the roll rotate, they grip and rolladvanced up to a stop. As the roll rotate, they grip and roll
down the stock.down the stock.

17.  First the work piece is fed into the rolls atFirst the work piece is fed into the rolls at
the correct place in the roll's revolution.the correct place in the roll's revolution.
The rolls turn, acting to pull the work intoThe rolls turn, acting to pull the work into
the gap. As the work piece is fed throughthe gap. As the work piece is fed through
the grooved portion of the roll's revolution,the grooved portion of the roll's revolution,
the compressive forces form the materialthe compressive forces form the material
into the desired shape.into the desired shape.

19.  So, the bar stock can be increased in length, reduced inSo, the bar stock can be increased in length, reduced in
diameter and changed in section as desired.diameter and changed in section as desired.
 Roll forging manufacture is often used in the automotiveRoll forging manufacture is often used in the automotive
industry to manufacture parts. Shafts of variousindustry to manufacture parts. Shafts of various
geometries, hand tools and leaf springs, are somegeometries, hand tools and leaf springs, are some
products commonly manufactured by this process.products commonly manufactured by this process.
 Parts created by roll forging possess superiorParts created by roll forging possess superior
mechanical properties than those produced from manymechanical properties than those produced from many
other processes.other processes.