1. PDM 6
GROUP 2
IZZAT
HAIZA
ALIF
FAIRUZ
SAND CASTING
EXHAUST MANIFOLD

2. History
 The
Assyrian king Sennacherib (704681BC) cast massive bronzes of up to 30
tonnes, and claims to have been the first
to have used clay moulds rather than the
'lost-wax' method.

3.  In
1912, the sand slinger was invented by
the American company Beardsley &
Piper.
 In 1912, the first sand mixer with
individually mounted revolving plows
was marketed by the Simpson
Company.

4.  In
1915, the first experiments started with
bentonite clay instead of simple fire clay
as the bonding additive to the molding
sand. This increased tremendously the
green and dry strength of the molds.

In 1918, the first fully automated foundry
for fabricating hand grenades for the U.S.
Army went into production.

5. Part : Exhaust Manifold in Car
Casting Process (Sand Casting)
1.
2.
3.
4.
5.
6.
7.
8.
Study all type of casting available in the industry. List all of
them
Explain the function of exhaust manifold.
Study the suitable material to produce exhaust manifold.
Explain in detail about the casting process selected.
Explain the advantages and disadvantages of the casting
process selected.
Explain defects that occur from the selected.
Explore another type of manufacturing process to
produce exhaust manifold.
Make comparison between both types of the
manufacturing process.

6. Haiza
Will explain about question no 1 and 2 .
^_^

7. All type of casting in industry
1
. Type of casting available In industry
 2 . Explain the function of exhaust
manifold

8. All type of Casting :
 Sand
casting
 Permanent mold casting
 Investment casting
 Lost foam casting
 High pressure die casting
 Centrifugal casting
 Glass casting

9. Sand Casting
 Sand
casting, also known as sand molded
casting, is a metal casting process
characterized by using sand as
the mold material. Over 70% of all metal
castings are produced via a sand casting
process.

12. Matchplate sand molding
 The
principle of the matchplate, meaning
pattern plates with two patterns on each
side of the same plate, was developed
and patented in 1910, fostering the
perspectives for future sand molding
improvements.

13. > The method alike to the DISA's (DISAMATIC) vertical
moulding is flaskless.
> Its great advantage is inexpensive pattern tooling,
easiness of changing the molding tooling.

15. Permanent mold casting




Permanent mold casting is metal casting process
that employs reusable molds ("permanent molds"),
usually made from metal.
The most common process uses gravity to fill the
mold, however gas pressure or a vacuum are also
used.
A variation on the typical gravity casting process,
called slush casting, produces hollow castings.
Common casting metals
are aluminum, magnesium, and copper alloys.
Other materials include tin, zinc, and lead alloys
and iron and steel are also cast in graphite molds.

17. The Process
 Gravity
process
 Mold
 Slush
 Low
pressure
 Vaccum

18. Investment casting



Investment casting is an industrial process based
on and also called lost-wax casting, one of the
oldest known metal-forming techniques.
From 5,000 years ago, when beeswax formed the
pattern, to today’s high-technology waxes,
refractory materials and specialist alloys, the
castings allow the production of components with
accuracy, repeatability, versatility and integrity in
a variety of metals and high-performance alloys.
Lost-foam casting is a modern form of investment
casting that eliminates certain steps in the process.

19. 


The process is generally used for small
castings, but has been used to produce
complete aircraft door frames, steel castings
of up to 300 kg (660 lbs)
andaluminium castings of up to 30 kg (66 lbs).
It is generally more expensive per unit
than die casting or sand casting, but has
lower equipment costs.
It can produce complicated shapes that
would be difficult or impossible with die
casting, yet like that process, it requires little
surface finishing and only minor machining.

21. Lost-foam Casting
 Lost-foam
casting (LFC) is a type
of evaporative-pattern casting process
that is similar to investment
casting except foam is used for
the pattern instead of wax.
 This process takes advantage of the
low boiling point of foam to simplify the
investment casting process by removing
the need to melt the wax out of the mold.

23. Die Casting



Die casting is a metal casting process that is
characterized by forcing molten metal under
high pressure into a mold cavity.
The mold cavity is created using two
hardened tool steel dies which have been
machined into shape and work similarly to
an injection mold during the process.
Most die castings are made from nonferrous metals,
specifically zinc, copper, aluminium, magnesi
um, lead, pewter and tin based alloys.

24.  Die
castings are characterized by a very
good surface finish (by casting standards)
and dimensional consistency.
 Two variants are pore-free die casting,
which is used to eliminate gas
porosity defects; and direct injection die
casting, which is used with zinc castings to
reduce scrap and increase yield.

26. Centrifugal Casting
 Centrifugal
casting is a metallurgical
manufacturing process by casting that
may refer to either:
 Centrifugal casting (industrial), on an
industrial scale
 Centrifugal casting (silversmithing), for a
smaller scale
 A related process is spin casting

28. Glass Casting
 Glass
casting is the process in
which glass objects are cast by directing
molten glass into a mould where it
solidifies.
 Modern cast glass is formed by a variety
of processes such as kiln casting, or
casting into sand, graphite or metal
moulds.

30. Function of Exhaust Manifold




Exhaust manifolds are generally simple cast iron or
stainless steel units which collect engine exhaust from
multiple cylinders and deliver it to the exhaust pipe.
For many engines, there are aftermarket tubular
exhaust manifolds known as headers in US English,
as extractor manifolds in British and Australian
English, and simply as "tubular manifolds" in UK
English.
These consist of individual exhaust headpipes for
each cylinder, which then usually converge into one
tube called a collector.
Headers that do not have collectors are called
'zoomie headers'.

31. 



Another form of modification used is to insulate a
standard or aftermarket manifold.
This decreases the amount of heat given off into
the engine bay, therefore reducing the intake
manifold temperature. There are a few types of
thermal insulation but three are particularly
common:
Ceramic paint is sprayed or brushed onto the
manifold and then cured in an oven.
These are usually thin, so have little insulatory
properties; however, they reduce engine bay
heating by lessening the heat output via radiation.

32. 



A ceramic mixture is bonded to the manifold
via thermal spraying to give a tough ceramic
coating with very good thermal insulation.
This is often used on performance production
cars and track-only racers
Exhaust wrap is wrapped completely around
the manifold.
Although this is cheap and fairly simple, it can
lead to premature degradation of the
manifold.

33.  the
function of an exhaust manifold on a
gasoline or diesel engine is to expel the
burnt fuel from
 the combustion chamber of each piston
out through the exhaust pipe after each
combustion stroke of
 the piston has been completed.

34. Izzat
Will explain :
3. Suitable material to produce exhaust
manifold.
4. Detail about casting process selected.

35. Suitable material to produce
exhaust manifold




Materials used for exhaust piping, mufflers, and
other exhaust system components consist mainly
of ferrous alloys.
Aluminum alloys are sometimes used as a coating
on ferrous alloys to impart additional corrosion
resistance.
In some cases, nonferrous nickel and titanium
alloys are used in exhaust system components in
especially demanding and/or high performance
applications.
Ceramics have also seen limited use in exhaust
systems to take advantage of their insulating
properties.

39. 


Ceramics and specialized metal alloys, albeit with
different compositions and properties than those
used in piping systems, are also commonly used in
substrates for aftertreatment devices—
ceramic and metallic catalyst substrates and
particulate filter substrates.
These materials are discussed in more detail in the
papers dealing with aftertreatment.
Ferrous alloys are based on iron-carbon alloys and
include carbon steel, alloy steels, stainless steel
and cast iron. Alloying elements are added to:

40.  Provide
solid solution strengthening of
ferrite,
 Cause the precipitation of alloy carbides
rather than cementite Fe3C,
 Improve corrosion resistance and other
special characteristics.

42. The varieties of stainless steel
available, two that are important
exhaust system materials are:
 Ferritic
stainless steel, and ;
 Austenitic stainless steel.
 Ferrous alloys can contain three important
grain structures: ferrite, austenite and
martensite. In ferrite, the iron atoms form a
body centered cubic (BCC or α-iron)
structure with iron atoms at each corner
of a cube and one in the center of the
cube, Figure 1.

43. 

Austenite is a face centered cubic (FCC or γiron) structure with iron atoms at each corner
and on the center of each face of a cube.
Interstitial holes in the FCC structure allow
austenite to accommodate a greater
number of carbon atoms, up to 2.11% by
weight, than the BCC structure of ferrite which
can accommodate up to 0.0218% carbon.
Austenite can be transformed into martensite,
a very hard and brittle grain structure that is
not normally used in exhaust piping systems.

45. 4 . Explain in detail about the
casting process selected ( sand
casting )




Sand casting, also known as sand molded
casting, is a metal casting process
characterized by using sand as
the mold material.
The term "sand casting" can also refer to an
object produced via the sand casting
process.
Sand castings are produced in
specialized factories called foundries.
Over 70% of all metal castings are produced
via a sand casting process.[

46.  Sand
casting is relatively cheap and
sufficiently refractory even for steel
foundry use. In addition to the sand, a
suitable bonding agent (usually clay) is
mixed or occurs with the sand.
 The sand is typically contained in a system
of frames or mold boxes known as a flask.
 The mold cavities and gate system are
created by compacting the sand around
models, or patterns, or carved directly
into the sand.

47. Basic Process
There are six steps in this process:
 Place a pattern in sand to create a mold.
 Incorporate the pattern and sand in a
gating system.
 Remove the pattern.
 Fill the mold cavity with molten metal.
 Allow the metal to cool.
 Break away the sand mold and remove
the casting.

49. Component
Patterns
 Builds a pattern of the object to be
produced, using wood, metal, or a plastic
such as expanded polystyrene. Sand can
be ground, swept orstrickled into shape
 The metal to be cast will contract during
solidification, and this may be non-uniform
due to uneven cooling.

50.  Different
scaled rules are used for different
metals, because each metal and alloy
contracts by an amount distinct from all
others
 Patterns also have core prints that create
registers within the molds into which are
placed sand cores.

51. Molding box and materials
Molding box and materials
 A multi-part molding box (known as a casting
flask, the top and bottom halves of which are
known respectively as the cope and drag) is
prepared to receive the pattern.
 Molding boxes are made in segments that
may be latched to each other and to end
closures
 The sand is packed in through a vibratory
process called ramming, and in this case,
periodically screeded level.
 The surface of the sand may then be
stabilized with a sizing compound.

52.  The
pattern is placed on the sand and
another molding box segment is added.
 Additional sand is rammed over and
around the pattern.
 Finally a cover is placed on the box and it
is turned and unlatched, so that the
halves of the mold may be parted and
the pattern with its sprue and vent
patterns removed.

53. Chills
 To control the solidification structure of the
metal, it is possible to place metal
plates, chills, in the mold.
 The associated rapid local cooling will form a
finer-grained structure and may form a
somewhat harder metal at these locations.
 In ferrous castings, the effect is similar
to quenching metals in forge work..

54. Cores
Cores
 To produce cavities within the casting—such
as for liquid cooling in engine blocks
and cylinder heads—negative forms are used
to produce cores.
 Usually sand-molded, cores are inserted into
the casting box after removal of the pattern.
Whenever possible, designs are made that
avoid the use of cores, due to the additional
set-up time and thus greater cost.

55. Design requirements



The part to be made and its pattern must be
designed to accommodate each stage of
the process, as it must be possible to remove
the pattern without disturbing the molding
sand and to have proper locations to receive
and position the cores.
A slight taper, known as draft, must be used
on surfaces perpendicular to the parting line,
in order to be able to remove the pattern
from the mold.
The sprue and risers must be arranged to
allow a proper flow of metal and gasses
within the mold in order to avoid an
incomplete casting.

56. 


Should a piece of core or mold become
dislodged it may be embedded in the final
casting, forming a sand pit, which may render
the casting unusable
Gas pockets can cause internal voids. These
may be immediately visible or may only be
revealed after extensive machining has been
performed.
For critical applications, or where the cost of
wasted effort is a factor, non-destructive
testing methods may be applied before
further work is performed.

58. Green Sand

These expendable molds are made of wet sands
that are used to make the mold's shape. The name
comes from the fact that wet sands are used in the
molding process. Green sand is not green in color,
but "green" in the sense that it is used in a wet state
(akin to green wood). Unlike the name suggests,
"green sand" is not a type of sand on its own, but is
rather a mixture of:

silica sand (SiO2), or chromite sand (FeCr2O),
or zircon sand (ZrSiO4), 75 to 85%, or olivine,
or staurolite, or graphite.
bentonite (clay), 5 to 11%
water, 2 to 4%
inert sludge 3 to 5%
anthracite (0 to 1%)





59. Another process of Sand
casting




Horizontal sand flask molding
In the first automatic horizontal flask lines the sand
was shot or slung down on the pattern in a flask and
squeezed with hydraulic pressure of up to 140 bars.
The subsequent mold handling including turn-over,
assembling, pushing-out on a conveyor were
accomplished either manually or automatically. In
the late fifties hydraulically powered pistons or multipiston systems were used for the sand compaction in
the flasks.
This method produced much more stable and
accurate molds than it was possible manually
or pneumatically

62. Aliff Afeqi
Will guide you about
Advantages and disadvantages of casting
process (Sand Casting) . . .
And Defect that Occur the process.
^_^

63. Advantages and disadvantages of casting
process selected
Disadvantages
Advantages






Advantages:
1)
Low capital investment
means that short production
runs are viable;
2)
Use of sand cores allows
fairly complex shapes to be
cast;
3)
Large components can
be produced;
4)
Suitable for small banch
production( small production
rates)




Disadvantages:
1)
The process has a high unit
cost, as it is labor intensive and time
consuming;
2)
The sand mold leaves bad
surface finish, due to sand
indentation and oxidizing medium,
which often requires further
processing;
3)
Cannot make thin sections;
4)
Not suitable for mass
production, oftenly used to
produce few number of products
compared with other casting
proccesses which produce
thousands and millions.

64. Defect that occur sand
casting




Production of castings involves a large number of
steps including casting design, pattern making,
moulding, melting, pouring, shake out, fettling,
inspection and finishing.
It is not uncommon for one or more of these steps to
be performed unsatisfactorily due to use of defective
material or equipment, carelessness of the operator
or lack of skill.
Such unsatisfactory operations result in a defective
casting which may be rejected at the final stage.
Since reclamation of defective castings is often
costly and sometimes outright impossible, care
should be taken to avoid the occurrence of the
defects in the first instance.

65. 










It is therefore necessary to understand the
various defects that occur in sand castings
and the main factors that are responsible for
their occurrence.
Some of the common defects are described
below.
1. Open Blows and Blow Holes
2. Pin Hole Porosity
3. Entrapped Air and other gases
4. Cracked Casting
5. Bent or Twisted Casting
6. Dropped Mould
7. Fusion
8. Swell
9. Run out

66.  10.
Mismatch
 11. Mis-run and Cold Shut
 12. Shrinkage-Faults
 13. Rat Tail and Buckles
 14. Core Shift
 15. Inclusions
 16. Cuts and Washes
 17. Metal penetration
 18. Hard Spots
 19. Scabs
 20. Hot tears

67. Shrinkage Faults:



Shrinkage faults are faults caused by improper
directional solidifications, poor gating and risering
design and inadequate feeding.
Solidification leads to volumetric contraction
which must be compensated by feeding. If this
compensation is inadequate either surface
shrinkage or internal shrinkage defects are
produced making the casting weaker.
Shrinkage faults can be reduced by providing
proper gating system, pouring at correct
temperature and taking care of directional
solidification.

69. Rat Tail and Buckles:




Rat tails and buckles are caused by the
expansion of a thin outer layer of moulding sand
on the surface of the mould cavity due to metal
heat.
A rat tail is caused by depression of a part of the
mould under compression which appears as an
irregular line on the surface of the casting.
A buckle is a more severe failure of the sand
surface under compression.
The mould must provide for proper expansion
instead of forming compressed layers to avoid this
defect.

71. Core Shift:
A core shift results from improper support
or location of a core.
 It results in a faulty cavity or hole in the
casting.
 It can be reduced by providing proper
support for cores and correct alignment
with the mould.


74. Sand casting
 Sand casting has many defects that can
occur due to the mold failing. The mold
usually fails because of one of two reasons:
the wrong material is used or it is improperly
rammed.
 The first type is mold erosion, which is the
wearing away of the mold as the liquid metal
fills the mold.
 This type of defect usually only occurs in sand
castings because most other casting
processes have more robust molds.
 The castings produced have rough spots and
excess material.

75. Fairuz
Will ending the presentation with explain
about :
7) Explain another type manufacturing
process to produce Exhaust Manifold
8) Make comparision between both type of
manufacturing process,

76. Die Casting
Die casting is a metal casting process that is
characterized by :
 forcing molten metal under high pressure into
a mold cavity.
 The mold cavity is created using two
hardened tool steel dies which have been
machined into shape and work similarly to
an injection mold during the process.
 Most die castings are made from nonferrous metals,
specifically zinc, copper, aluminium, magnesium, l
ead, pewter and tin based alloys.

77.  Depending
on the type of metal being
cast, a hot- or cold-chamber machine is
used.
 The casting equipment and the metal
dies represent large capital costs and this
tends to limit the process to high volume
production.
 Die castings are characterized by a very
good surface finish (by casting standards)
and dimensional consistency.

78.  Process
 The
following are the four steps
in traditional die casting, also known
as high-pressure die casting, these are
also the basis for any of the die casting
variations,die preparation,filling,ejection,
and shakeout.

79.  The
dies are then closed and molten
metal is injected into the dies under high
pressure; between 10 and 175
megapascals (1,500 and 25,400 psi)
 Finally,
the shakeout involves separating
the scrap, which includes
the gate, runners, sprues and flash, from
the shot.

80. Comparision:
Sand Casting
Sand Casting
Advantages:
 1)
Low capital investment
means that short production
runs are viable;
 2)
Use of sand cores allows
fairly complex shapes to be
cast;
 3)
Large components can
be produced;
 4)
Suitable for small banch
production( small production
rates)
Die Casting
Advantages of die casting are :
 Cost per unit is minimum hence
economical.
 It requires less floor space as
compared to other casting
processes.
 Rate of production is high. 75 to
150 casts per hour in cold
chamber and 300 to 350 casts
per hour in hot chamber process.
 High surface finish is obtained
and often no further finishing is
required.

81. Comparision
Sand Casting





Disadvantages:
1)
The process has a high
unit cost, as it is labor intensive
and time consuming;
2)
The sand mold leaves
bad surface finish, due to sand
indentation and oxidizing
medium, which often requires
further processing;
3)
Cannot make thin
sections;
4)
Not suitable for mass
production, oftenly used to
produce few number of
products compared with other
casting proccesses which
produce thousands and
millions.
Die Casting
Disadvantages :
 1) All metals and
alloys can not be
cast.
 2) The cost of
machines, dies and
other equipment used
is high.
 3) Not economical for
small quantity
production.
 4) Heavy casting
cannot be cast.

82. Sand casting : Over 70% of all metal
castings are produced via a sand casting
process.
Die Casting : . Most die castings are made
from non-ferrous metals,
specifically zinc, copper, aluminium,
magnesium, lead, pewter and tin bas
ed alloys.

84. THE END
End of Presentation
About Sand Casting.
From group 2 :
- Izzat
- Haiza
- Aliff Afeqi
- Fairuz
Assalamualaikum ,
Thanks to Sir Azam
And friend ^_^