Manufacturing Process of Bricks by Shehzad

1. Week 01
1st Topic : Manufacturing Process of Bricks
Teacher Name : Muhammad Hadi Arzoo
Department & Program : S & T (Civil) - M/E
Subject : Materials and Methods of Construction

2. BRICKS – Clay Material and Ingradients
• Clay is the basic material in brick making. There are six basic ingredient of brick. The general
percentage of these ingredients in brick is given below:
• Silica (Sand) and Alumina (Clay), these two are the most prominent ingredients in brick clay.
When mixed with water in proper proportions, it gains plasticity. The plastic mass can be
easily molded and dried. It should not go through cracking, shrinkage or warping.

3. BRICK MANUFACTURING PROCESS
1. Preparation of Clay:
The clay for bricks is prepared in the following order:
(i) Un-soiling:
The top layer of soil, about 200 mm in depth, is taken out and thrown away. The clay in top soil
is full of impurities and hence it is to be rejected for the purpose of preparing bricks.
(ii) Digging:
The clay is then dug out from the ground.
(iii) Cleaning: The clay, as obtained in the process of digging, should be cleaned of stones,
pebbles, vegetable matter, etc.
(iv) Weathering: The clay is then exposed to atmosphere for softening or mellowing. The
period of exposure varies from few weeks to full season. For a large project, the clay is dug out
just before the monsoon and it is allowed to weather throughout the monsoon.

4. BRICK MANUFACTURING PROCESS
(v) Tempering
In the process of tempering, the clay is brought to a proper degree of hardness and it is made
fit for the next operation of molding.
The water in required quantity is added to clay and the whole mass is pressed under the feet
of men or cattle.
The tempering should be done exhaustively to obtain homogeneous (similar) mass of clay of
uniform character.
For manufacturing good bricks on a large scale, the tempering is usually done in a pug mill.

5. BRICK MANUFACTURING PROCESS
Tempering of Clay (Pug mill and By foot)

6. BRICK MANUFACTURING PROCESS
2. Molding of Brick
Bricks are molded in many ways depending on the quality of the product to be made.
Generally the molding is done in the following two ways
• Hand molding
• Machine molding
For hand molding the tempered clay is forced in the mold in such a way that it fills all the
corners of the mound. Extra clay is removed either by wooden strike or frame with wire. Mold
is then lifted up and raw brick is left on ground.
Machine molding is used where large numbers of bricks are to be made. Machines used for
molding is generally of two types.
Plastic clay machines
Dry clay machines

7. BRICK MANUFACTURING PROCESS
Plastic Clay:
In plastic clay machine the clay in plastic state is forced to rectangular openings of a size equal
to the length and breadth of the bricks and are then cut into strips of thickness of the brick
with wires in frames.
Dry Machine:
In dry clay machines, dry clay is reduced to powder, filled dry into mold by the machine and
then are subjected to high pressure to form hard and well-shaped brick
Dry Clay Machine Plastic Clay Machine

8. BRICK MANUFACTURING PROCESS
3. Drying of Bricks:
Drying is usually done by placing the bricks in sheds with open sides so as to ensure free
circulation of air and protection from bad weather and rains. The bricks are allowed to dry till
they are left with 5 to 7 percent moisture content. The drying period usually varies from 7 to
14days. The molded bricks are dried because of the following reasons.
• If damp bricks or green bricks are directly taken to burning then, they are likely to be
cracked and distorted
• To remove maximum moisture from the brick so as to save time and fuel during burning
• To increase the strength of raw bricks so that they can be handled and stacked in greater
heights in the kiln for burning without damage.

9. BRICK MANUFACTURING PROCESS
Drying of Bricks

10. BRICK MANUFACTURING PROCESS
4. Burning of Brick
Bricks are fired and cooled in a kiln, an oven-type chamber capable of producing temperatures
of 870° to 1,100° C (1,600° to more than 2,000° F), depending on the type of raw material.
It is the very important step in manufacture of bricks. Bricks may be burnt by two distinct
methods given below.
1. Burning in a clamp known as clamp burning (Scove Kiln)
2. Burning in a flame kiln known as kiln burning
• In clamps, one batch of green bricks is heaped along with firewood, coal etc. and sealed
with clay.
• It is then fired slowly to intense heat which may take many days. Modern kilns, however,
permanent structures consisting of many chambers.
• There are intermittent (discontinous) and continuous kilns. Molded clay is stacked in the
chambers. They are then slowly dried and burned to high temperature and cooled.
.

11. BRICK MANUFACTURING PROCESS
• One cycle of loading, drying, burning, cooling and emptying may take as much as
two weeks. .
Scove or Clamp Burning Kiln Burning

12. BRICK MANUFACTURING PROCESS
5. Setting and Packaging of Brick
After the brick is fired and cooled, it is unloaded from the kiln car, which has been
automated to the point where almost all manual brick handling is eliminated.
Automated setting machines have been developed that can set brick at rates of over
18,000 per hour and can rotate the brick 180 degrees.
Usually set in rows eleven bricks wide, a stack is wrapped with steel bands and fitted
with plastic strips that serve as corner protectors.
The packaged brick is then shipped to the job site, where it is typically unloaded using
boom trucks.
.

13. BRICK MANUFACTURING PROCESS
5. Setting and Packaging of Brick
.

14. BRICK MANUFACTURING PROCESS
6. Transport of Bricks
Bricks are stored in the stockyard to facilitate stock rotation.
On being dispatched from the factory, the bricks are usually loaded onto crane-
equipped lorries for delivery to customers. Destinations often include builders
merchants' yards, from which further deliveries take place, which could include direct
delivery to housing development or commercial project sites.
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16. BRICK MANUFACTURING PROCESS
Dry Clay Macine: https://www.youtube.com/watch?v=3InvdM0Tin4
Plastic Clay Machine: https://www.youtube.com/watch?v=TZ3y1PQDcbI
https://civilblog.org/2014/02/25/4-primary-steps-involves-in-brick-manufacturing/