Engineering

How Clay Bricks are Made ( Step by Step Explanation )

Written by Thalib Tantary

If you’ve been looking for how a brick is made or how bricks are manufactured in home, then you are advised to keep reading every single bit of this article.

Brick which is made from clay is a rectangular shaped structure. Despite living in cement age, bricks still have a defined space in our societies. Bricks are used in building homes, schools, factories etc. Here are operations that are involved in the brick manufacturing process:

1. Preparation of brick earth

The brick earth is prepared in the following steps:

  • Selection of the site and un-soiling

The site for taking out earth shall be the suitability of soil. After selection the site, the top layer of soil about 20cm in depth, is removed and thrown out. This top layer of the soil contains root of grass, vegetation, other organic matters etc. And is therefore rejected.

  •  Digging and Cleaning

The soil below 20cm is dug out preferably before rains. It is then cleaned of stones, pebbels, vegetable matters etc. All the lumps of soil should be broken into powder form.

  • Weathering

The loose soil thus obtained after cleaning is exposed to weather for softening. The period of weathering varies from few weeks to full season, depending upon the type of soil and time available.

  •  Blending

The weathered soil is the loosened. The deficient ingredients to be added are placed in layer at the top of heap of the weathered soil. The whole mass is then throughly mixed. Blending indicates intimate or harmonious mixing of all the ingredients of soil to be used as brick earth.

  • Tempering

After blending a required quantity of water is added to the soil and whole mass kneaded well under the feet of man or cattle so as to obtain homogeneous mass of brick earth of uniform character.

Tempering may be done manually or mechanically. For manufacturing ordinary bricks on small scale, tempering may be done.

Manually and for good bricks on large scale it may be done mechanically. Mechanical tempering is done easily and effectively by means of a machine, known as pug mill.

2. Moulding Of Bricks

The process of making bricks from the pugged earth with the help of mould is known as moulding of bricks. The bricks are moulded by the following two methods:

  • Hand moulding:

The process of making bricks with the help of a mould by manual labour is known as hand moulding. Hand moulding are of two types

a) Ground moulding:

The process of making of bricks on the ground by manual labour is known as ground moulding.

b) Table moulding:

The process of moulding of bricks on a table by manual labour is known as table moulding.

  • Machine moulding:

The process of moulding of bricks by means of a machine is known as machine moulding.

3. Drying of bricks

The process of stacking bricks with spaces in between for free circulation of air so as to remove their moisture content is known as drying of bricks.

The bricks may be dried by anyone of the following two methods:

  • Natural drying (or open air drying)

The process of drying the bricks in open air is known as natural or open air drying.

  • Artificial drying

The process of drying bricks in special driers is known as artificial drying. This method is adopted when bricks are required at a fast rate and is large quantity. In this process bricks are heated in a special drier known as tunnel drier, room drier or chamber drier. The raw bricks are carried on trollies which are passed through drying chamber, gradually from one end and are removed in dry from the other end. The tempreture in this drying chamber is usually kept less than 120℃. The time required for drying in this process varies from 1 to 3 days.

4. Burning of bricks

After drying the bricks are burnt to make them hard strong and durable. The bricks may be brunt by any of the following two different ways:

  • Clamp burning

The process of burning of bricks in a clamp, pozawah or open kiln is known as clamp burning. The arrangement and shape of clamp widely vary in different parts in india.

Clamp

A temporary structures in which bricks are brunt once at a time is known as clamp.  It is also known as pozawah, open kiln or kumhar’s kiln. It consists of a sloped surface which is generally trapezoidal shape. The shorter parallel side of the surface is about half as long as the wider side.

The shorter end is kept about 30cm in excavation while the wider end is raised a little above the ground by earth filling. The surface is generally given an upward stripe of about 15%. The size of the clamp depends upon the number of bricks required to be burnt at a time. Usually for burning one lac bricks a clamp of size 15m × 13m × 5m is considered sufficient and the outcome varies from thirty thousands to one lack of bricks.

  • kiln burning

The process of burning of bricks in a flame kiln or bhatta is called burning. Kiln burning can be done in any of the following two types of kilns:

a) Intermittent or semi continuous kiln

A permanent structure in which bricks are burnt at a time again and again is known as intermittent or semi continuous kiln. In such kilns the supply of bricks is also not continuous. They may be either rectangular or circular in shape.

b) Continuous kilns

A permanent structure in which bricks are burnt continuously is known as continuous kiln. In these kilns loading, per heating burning, cooling and unloading of bricks are done simultaneously.

About the author

Thalib Tantary

My name is Thalib Mushtaq Tantary and i am the founder of this very site. I am a medical or civil engineering student and i love to help people get out of trouble they counter in their lives.
Since most often students find it difficult to understand their text books or even there many who can not afford such books, therefore we prepared ourselves to solve this problem faced by them.

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