Manufacturing of Bricks - Civil Engineering Materials - by Engr. Muhammad Baqir

1. MANUFACTURING
OF BRICKS
ENGR. MUHAMMAD BAQIR
M.E Civil Engineering

2. MANUFACTURIN
G OF BRICKS
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2
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Preparation of Clay or Brick Earth
Moulding of Brick
Drying of Brick
Burning Brick
PROCEDURE

3. PREPARATION OF CLAY OR BRICK
EARTH
1 Selection of Raw Materials:
• The primary raw material for brick
manufacturing is clay.
• The quality and composition of the raw
materials play a crucial role in
determining the properties of the
finished bricks.
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4. PREPARATION OF CLAY OR BRICK
EARTH
2 Removal of Loose Soil:
• After selecting a site the top layer of the soil
about 30cm depth contains a lot of impurities
such as stones, lime particles, vegetable
matter and hence it should be taken out and
thrown away.
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6. PREPARATION OF CLAY OR BRICK
EARTH
3 Digging, Spreading and Cleaning
• The earth is than dug out from the ground.
• This earth is spread in to heaps about 50 to 150
cm height.
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4 Weathering
• The soil is then mixed with little quantity of
water then exposed to atmosphere for softening
for few weeks to a season.
• It improves its plasticity and strength.

7. PREPARATION OF CLAY OR BRICK
EARTH
5 Blending
• The clay is then mixed with suitable ingredients.
• It is carried out by taking a small portion of clay every
time
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6 Tempering
• It consists in kneading the blended soil under feet of
labors or cattle to make it stiff and plastic, water is added
from time to time and tempering continues till homogenous mass of earth is obtained.
• It is then covered with cloth or mats and allowed to dry gradually (for not less than 36 hours) till it
is just soft enough for molding.

9. MOULDING OF
BRICKS
Giving the required shape
and size to the prepared clay
is known as Moulding of
Bricks.
Moulding of Bricks is divided
into two types.
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HAND MOULDING
MACHINE MOULDING

10. MOULDING OF BRICKS 10
HAND MOULDING MACHINE MOULDING

11. MOLDING OF BRICKS
1 Hand Moulding
• When molding is done with hands it is called hand molding.
• A wooden rectangular mold made in the shape of brick is normally used for this purpose.
• It is extensively used in Pakistan.
It is further sub divided into two types.
a. Ground Moulding
b. Table Moulding
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12. MOLDING OF BRICKS
1 Hand Moulding
 Ground Moulding
This method is adopted when a large area of land is available for the purpose. Area must levelled,
plastered and sand is sprinkled over it, To prevent moulded bricks from sticking to the moulds or
the mould is dipped in water each time before moulding is done.
 Table Moulding
This process of moulding is done on table by manual labors is known as table moulding, it is verily
used in our country.
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13. MOLDING OF BRICKS
5 Machine Moulding
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• The clay is placed in the machine, it comes
out through the opening under pressure.
• It is a cut to bricks by steels wires fixed into
frames.
• These bricks are also known as wire cut
bricks.

14. DRYING OF
BRICKS
Wet bricks from moulding or
cutting machines contains 7
to 30 percent moisture. If
the bricks not completely
dried then these bricks likely
to get cracked when burnt.
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15. DRYING OF BRICKS 15
1 Natural Drying
• Freshly molded bricks are arranged in open-air spaces or drying yards.
• Bricks are stacked with gaps between them to allow air circulation.
• Excess water within the bricks evaporates gradually due to exposure to air and sunlight.
• This process typically takes several days, and the duration depends on factors like weather
conditions and the size of the bricks.
• Once adequately dried, bricks are ready for the firing process in a kiln.
• Careful monitoring is essential to prevent over-drying or insufficient drying.

16. DRYING OF BRICKS 16
2 Artificial Drying
Artificial drying is particularly advantageous in regions with unfavorable weather conditions for natural
drying. It offers better control over the drying process and allows for a more efficient and timely
production of bricks.
• Bricks are placed in specially designed drying chambers or tunnels.
• Temperature and humidity are controlled within the drying chambers to optimize the drying
process.
• Fans or other mechanisms facilitate forced air circulation within the drying chambers.
• The use of artificial heat sources, such as electric heaters or hot air blowers, accelerates the drying
process.

17. BURNING OF
BRICKS
The burning or firing of bricks is a critical step
in the brick manufacturing process that
involves subjecting the molded bricks to high
temperatures in a kiln to achieve hardness
and durability.
There are several types of brick firing methods:
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18. BURNING OF BRICKS 18
1 Clamp Burning
• Traditional and relatively simple method.
• Bricks are arranged in stacks, called clamps,
and fired in the open air using a circular or
rectangular arrangement.
• This method is less controlled compared to
modern kilns and is often used in smaller-
scale or traditional brick-making operations.
Temporary Structure built on site

19. BURNING OF BRICKS 19
2 Kiln Burning
• Kiln burning of bricks is a manufacturing process that
involves subjecting molded clay bricks to high
temperatures within a kiln.
• This controlled heating process imparts hardness and
durability to the bricks, transforming them from a raw
clay state into a solid, finished product suitable for
construction.
• Burning is done continuously in Kilns.
• Rate of Burning is also high.
• Initial investment for kiln is very high. Permenent Structure

20. THANK YOU
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