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9
ME 4563 Fall ’05 Dr. S. Haran
Direct Applications
Direct Applications
-
-
where rolled
where rolled
plates/sheets are used
plates/sheets are used
•
•
Aircraft bodies
Aircraft bodies
•
•
Ship hulls
Ship hulls
•
•
Reactor vessel
Reactor vessel
walls
walls
•
•
Boilers
Boilers
•
•
Bridges
Bridges
•
•
Tanks, etc.
Tanks, etc.
Rolling
Rolling
Indirect Applications
Indirect Applications
-
-
where rolled plates/sheets
where rolled plates/sheets
are used after further
are used after further
processing
processing
•
•
Locomotives
Locomotives
•
•
Automobiles
Automobiles
•
•
Appliances
Appliances
•
•
Food/Beverage
Food/Beverage
containers
containers
•
•
Office equipment,
Office equipment,
•
•
Construction, etc. etc.
Construction, etc. etc.
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ME 4563 Fall ’05 Dr. S. Haran
Classifications of Rolling Material
Classifications of Rolling Material
Rolling material is separated into classifications based
Rolling material is separated into classifications based
on the material's cross
on the material's cross
-
-
sectional dimensions
sectional dimensions
Cross
Cross
-
-
Section
Section
Thickness
Thickness
Width
Width
Bloom
Bloom
Square
Square
> 6 in.
> 6 in.
< 2 * thickness
< 2 * thickness
Billet
Billet
Square or Circular
Square or Circular
< 6 in.
< 6 in.
< 2 * thickness
< 2 * thickness
Slab
Slab
Rectangular
Rectangular
> 2 * thickness
> 2 * thickness
Plate
Plate
0.25 in. < x < 12 in.
0.25 in. < x < 12 in.
Sheets
Sheets
0.008 in. < x < 0.25 in.
0.008 in. < x < 0.25 in.
Foil
Foil
<0.008 in.
<0.008 in.
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
What kind of Thickness are we talking about ?
What kind of Thickness are we talking about ?
When Manufactured:
When Manufactured:
Rolled Plates: normally > 6mm
Rolled Plates: normally > 6mm
Rolled Sheets: normally < 6mm
Rolled Sheets: normally < 6mm
•
•
Aircraft Body: 1
Aircraft Body: 1
–
–
2mm thick
2mm thick
•
•
Aluminum beverage cans: 0.1
Aluminum beverage cans: 0.1
–
–
0.28mm thick
0.28mm thick
•
•
Aluminum Foil: 0.008mm thick (wrapping)
Aluminum Foil: 0.008mm thick (wrapping)
And the range of applications
And the range of applications
…
…
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Two Major types of rolling processes
Two Major types of rolling processes
-
-
•
•
Flat rolling
Flat rolling
–
–
to produce Plates
to produce Plates
and
and
Sheets of metal
Sheets of metal
•
•
Profile (or Shape) rolling
Profile (or Shape) rolling
–
–
to
to
produce all other possible
produce all other possible
shapes
shapes
Rolling
Rolling
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13
ME 4563 Fall ’05 Dr. S. Haran
Flat Rolling
Flat Rolling
Hot Rolling
Hot Rolling
Cold Rolling
Cold Rolling
Pack Rolling
Pack Rolling
Flat Rolling Process can be
Flat Rolling Process can be
divided into THREE major
divided into THREE major
types:
types:
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Flat Rolling Process
Flat Rolling Process
Hot Rolling
Hot Rolling
Cold Rolling
Cold Rolling
Pack Rolling
Pack Rolling
Converts a cast structure into a
Converts a cast structure into a
wrought structure; rolled above the
wrought structure; rolled above the
re
re
-
-
crystallization temperature
crystallization temperature
(process in which new
(process in which new
equiaxed
equiaxed
/ strain free
/ strain free
grains are formed, replacing old grains)
grains are formed, replacing old grains)
Carried out a room temperature;
Carried out a room temperature;
better finish, mechanical properties
better finish, mechanical properties
Two or more layers of metals are
Two or more layers of metals are
rolled together; improves
rolled together; improves
productivity (Al foil)
productivity (Al foil)
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Other Flat Rolling Process
Other Flat Rolling Process
Temper Rolling
Temper Rolling
Leveling
Leveling
Sheets subject to a final pass
Sheets subject to a final pass
–
–
strain
strain
in the sheets are removed (sheets
in the sheets are removed (sheets
undergo yield point elongation
undergo yield point elongation
during rolling); also called
during rolling); also called
skin pass;
skin pass;
0.5 to 1.5% reduction in thickness
0.5 to 1.5% reduction in thickness
To improve flatness. Sheets may
To improve flatness. Sheets may
not be sufficiently flat due to
not be sufficiently flat due to
various reasons such as roll gap
various reasons such as roll gap
and process parameters
and process parameters
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Flat Rolling Process
Flat Rolling Process
Continuous
Continuous
Casting or Ingots
Casting or Ingots
Blooms
Blooms
Slabs
Slabs
Billets
Billets
Preliminary Rolling
Preliminary Rolling
::
::
Initial breakdown of Ingot or cast
Initial breakdown of Ingot or cast
slab
slab
Hot
Hot
Rolling
Rolling
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Blooms
Blooms
Slabs
Slabs
Billets
Billets
Preliminary Rolling ::
Preliminary Rolling ::
About 6
About 6
”
”
square in cross
square in cross
section; various lengths
section; various lengths
Thinner rectangular cross
Thinner rectangular cross
section; various lengths (thinner
section; various lengths (thinner
version of a bloom)
version of a bloom)
Smaller square cross sections;
Smaller square cross sections;
various lengths
various lengths
Rolling
Rolling
Flat Rolling Process
Flat Rolling Process
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ME 4563 Fall ’05 Dr. S. Haran
Continuous
Continuous
Casting or Ingots
Casting or Ingots
Blooms
Blooms
Slabs
Slabs
Billets
Billets
Preliminary Rolling
Preliminary Rolling
::
::
Hot
Hot
Rolling
Rolling
Continuous Flat Rolling
Continuous Flat Rolling
Process
Process
–
–
A Schematic
A Schematic
Casting
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ME 4563 Fall ’05 Dr. S. Haran
Slabs
Slabs
Hot Strip
Hot Strip
Mill
Mill
Directly to
Directly to
Rolling
Rolling
Pre Rolling
Pre Rolling
Plates
Plates
Tubes
Tubes
Pickling
Pickling
Cold
Cold
Rolling
Rolling
(acid bath)
(acid bath)
Flat Rolling Process
Flat Rolling Process
-
-
Products
Products
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Billets
Billets
Hot Rolled
Hot Rolled
Bars
Bars
Rods
Rods
Tube
Tube
Rounds
Rounds
Wire & wire
Wire & wire
products
products
Seamless
Seamless
Tubes
Tubes
Cold
Cold
-
-
drawn
drawn
Bars
Bars
Flat Rolling Process
Flat Rolling Process
-
-
Products
Products
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Blooms
Blooms
Structural
Structural
Shapes
Shapes
Rails
Rails
Flat Rolling Process
Flat Rolling Process
-
-
Products
Products
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Consists of these major categories:
Consists of these major categories:


Shape Rolling
Shape Rolling


Ring Rolling
Ring Rolling


Thread Rolling
Thread Rolling


Rotary Tube Piercing
Rotary Tube Piercing


Tube Rolling
Tube Rolling
Other Rolling Operations
Other Rolling Operations
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran


Raw materials is usually the Bloom
Raw materials is usually the Bloom


Straight structural shapes such as bars of various
Straight structural shapes such as bars of various
cross sections, channel sections, I
cross sections, channel sections, I
-
-
beams, and rails
beams, and rails


Rolled by passing the stock through a number of
Rolled by passing the stock through a number of
sets of rolls specially designed for these
sets of rolls specially designed for these
applications
applications


Designing the roll systems for this application
Designing the roll systems for this application
takes experience and care, as material failure is
takes experience and care, as material failure is
fairly frequent in case of poor designs
fairly frequent in case of poor designs
A.
A.
Shape Rolling
Shape Rolling
Other Rolling Operations
Other Rolling Operations
Rolling
Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Stages in the shape
Stages in the shape
rolling of an H
rolling of an H
-
-
section
section
part.
part.
Various other
Various other
structural sections,
structural sections,
such as channels and
such as channels and
I
I
-
-
beams, are also
beams, are also
rolled by this kind of
rolled by this kind of
process.
process.
Shape Rolling
Shape Rolling
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25
ME 4563 Fall ’05 Dr. S. Haran
A.
A.
Shape Rolling
Shape Rolling
Shape Rolling
Shape Rolling
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ME 4563 Fall ’05 Dr. S. Haran
Rolling out an
Rolling out an
angular section
angular section
Shape Rolling
Shape Rolling
A. Shape Rolling
A. Shape Rolling
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27
ME 4563 Fall ’05 Dr. S. Haran
Rolling out a
Rolling out a
V
V
-
-
Section
Section
Shape Rolling
Shape Rolling
A. Shape Rolling
A. Shape Rolling
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ME 4563 Fall ’05 Dr. S. Haran


Smaller diameter thick
Smaller diameter thick
ring is expanded into a
ring is expanded into a
larger diameter thinner
larger diameter thinner
ring
ring


System consists of two
System consists of two
rolls
rolls
–
–
one which performs
one which performs
the rolling and the other
the rolling and the other
to support and guide
to support and guide


With each rotation, the
With each rotation, the
thickness is reduced as
thickness is reduced as
the rings come closer
the rings come closer
together
together
B.
B.
Ring Rolling
Ring Rolling
Rolling
Rolling

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