School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
Introduction to Manufacturing
Lecture-4 : Casting – Part-1
IME 211
Presented by: Dr. Mohamed EL-Hofy
8th of November 2020
11/2/2020
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
CASTING
It is a method of making parts or products by pouring molten
metal into a mould
The mould forms a cavity having the shape and size of the part to
be casted (casted parts are called castings).
Casting are made in a shop called “Foundry”.
Examples of the common castings are: Machine Tool, engine
parts, motors castings, pipes, valves, large parts, toys, products
made of cast iron., etc.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
METAL CASTING PROCESSES
The process involves:
 Pouring molten metal into a mold patterned after the part to be manufactured
 Allowing it to solidify
 Removing the part from the mold
Advantages of Metal Casting Processes:
 Produce part in single step (“near-net” shape)
 Produce large parts
 Can produce a wide variety of shapes and sizes
 Complex shapes are possible
 Internal cavities are possible
Metals with good castability
Cast iron, copper, aluminum, magnesium.Tin and zinc- based alloys.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
FLUIDITY INDEX
A test method for fluidity using a spiral
mold. The fluidity index is the length of
the solidified metal in the spiral passage.
The greater the length of the solidified
metal, the greater is its fluidity.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
EXAMPLES OF CAST PRODUCTS
Note how difficult it might get to produce these parts using other manufacturing processes
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Industrial Engineering and Systems Management Department
IME-211 Lectures
CASING PROCESSES
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
CATEGORIES OF METAL-CASTING PROCESSES
Expendable Molds:
 Typically made out of sand, plaster, ceramics and similar
material
 Such material are refractory i.e, capable of withstanding high temperatures.
 After casting the mold is broken up to remove the casting
Permanent Molds:
 Made of metals that maintain their strength at high temperatures
Are used repeatedly
 Designed in such a way that the casting can be removed easily.

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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
EXPENDABLE MOULD CASTING
 Sand casting
 Produces, generally, inaccurate casting that will be further
machined to obtain the required accuracy and surface finish.
 Special casing processes
 As die casting, shell casting or investment casting can produce
final products with acceptable accuracy and surface finish.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
1-SAND CASTING
Green sand moulds
Molding sand is a mixture of sand, clay and water.
Process outline:
1.
2.
3.
4.
5.
6.
Place a pattern (having the shape of the desired casting) in sand to make an imprint
Incorporate a gating system
Remove the pattern and filling the mold cavity with molten metal
Allow the metal to cool until it solidifies
Break away the sand metal
Remove the casting
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
SAND CASTING
Sprues
– Holes through which molten metal is
poured
 Risers
– Reservoirs of molten metal to ensure
complete part filling
 Vents
– Holes allowing escape of gasses from
the melt
 Runners
– Networks through which the metal
flows in the mold
 Gates
– Areas where the metal enters the
impression (part)
- Sprues feed Runners.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
SAND CASTING PROCEDURE
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Industrial Engineering and Systems Management Department
IME-211 Lectures
VIDEO – SAND CASTING
 https://www.youtube.com/wa
tch?v=wGZa-M_jfw8
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Industrial Engineering and Systems Management Department
IME-211 Lectures
EXAMPLE (MOULDING 2 FLANGED PIPE)
Educational kit
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Industrial Engineering and Systems Management Department
IME-211 Lectures
EXAMPLE (MOULDING AN ANCHOR)
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Industrial Engineering and Systems Management Department
IME-211 Lectures
EXAMPLE (MOULDING A BELL)
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Industrial Engineering and Systems Management Department
IME-211 Lectures
11/2/2020
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Industrial Engineering and Systems Management Department
IME-211 Lectures
MOULD PREPARATION STEPS
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Industrial Engineering and Systems Management Department
IME-211 Lectures
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Industrial Engineering and Systems Management Department
IME-211 Lectures
CASTING STEPS
1. On the left is the top (cope) and on the
right is the bottom (drag) molding boxes.
2. The half-pattern is placed on the
base plate ready to take the sand.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
3. The sand is tipped in the box and
rammed down. The ramming tool is
shown in front. The wedged end is
used for the first ramming and the flat
end is used on the second ramming.
4. Once the ramming is complete and the
surface is leveled, the box is carefully
turned over on its back.
The exposed surface of the pattern is
clearly shown
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Industrial Engineering and Systems Management Department
IME-211 Lectures
5. The surface is dusted with parting
powder and the other half of the pattern is
placed on the first half still embedded in
the sand. The top box is placed on the
bottom box and skewed clockwise
against the registration pegs.
6. The runner (right tube) is pushed into
the sand in the bottom box and the riser
(left tube) is placed onto the pattern hub.
The tubes are held in place while the sand
is shoveled in.
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Industrial Engineering and Systems Management Department
IME-211 Lectures
7. The sand is rammed down and leveled off.
The runner basin is cut into the top surface
of the sand at this stage.
The boxes can now be separated (very
carefully).
8. The box halves with the pattern still in place.
The white surface is the parting powder
(talc).
The small hole in the sand is the well left by
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the runner tube.
School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
9. The pattern is removed by lightly tapping it.
The runner bar with its extension and the gate
is cut into the sand surface and smoothed off.
At this stage the boxes are put back together.
10. The completed mould ready to pour in
the molten cast iron.
The iron weights help keep the boxes
together during the pouring process.
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Industrial Engineering and Systems Management Department
IME-211 Lectures
11. The molten cast iron being poured into
the mould.
The slag is kept away from the pouring
lip.
12. The metal has cooled.
Note the runner basin on the right
and the riser opening to the left.
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Industrial Engineering and Systems Management Department
IME-211 Lectures
13. The casting is removed from the sand
and looks like this.
The riser and sprue are cut off the main
casting.
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Industrial Engineering and Systems Management Department
IME-211 Lectures
FINISHED CASTING
Both sprue, riser and runner should be removed by manual machining processes.
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Industrial Engineering and Systems Management Department
IME-211 Lectures
MOULDING A BRACKET
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Industrial Engineering and Systems Management Department
IME-211 Lectures
EXAMPLE OF CORING
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Industrial Engineering and Systems Management Department
IME-211 Lectures
PATTERN
Are models of the required casting.
Most patterns are made of wood.
Patterns, made of metal, usually aluminium, are use if more than 500 parts
are to be casted.
Shrinkage allowance is needed to compensate metal shrinkage during
solidification (10 mm/m for cast iron, 20 mm/m for cast steel and bronze).
Machining allowances are made for surfaces that will be machined only.
A draft about 10 mm/m is needed to pull out the pattern from the sand.
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
PATTERN ALLOWANCES
Pattern Allowances
1. Shrinkage allowance
2. Machining allowance
3. Draft allowance
4. Fillets
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
DRAFT ALLOWANCE
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Industrial Engineering and Systems Management Department
IME-211 Lectures
PATTERN AND CORE
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
SAND CORES
 Cores are used for internal cavities and passages
 Removed from the finished part during shakeout
 Must be strong, collapsible, permeable, heat resistant
 Made in a similar manner to mold making
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
CASTING SIMULATION
https://www.dhioresearch.com/products/z-cast/
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School of Innovative Design Engineering
Industrial Engineering and Systems Management Department
IME-211 Lectures
11/2/2020
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