How to check the quality of Table Mould Bricks?

Table Mould Brick Manufacturing Process:

1. Winning-

Digging clayey soil from agriculture fields or clay beds, transporting it to the moulding site and filtering it to remove stones and other impurities.

2.Preparation–

Mixing water in the ratio of 1:2 and filtering the clay out of the soil, mixing fly ash, stone dust, coal powder, rice husk, etc depending upon availability of these additives. However, the good quality soil may be directly mixed with additives and prepared for moulding. The selection of raw materials and other brick making process has been standardized in IS 11650: 1991.

3.Shaping–

Moulding either by hand or by machine using moulds. Machine moulding is reported better in terms of quality of bricks, i.e., compressive strength and uniformity. Hand moulded bricks are sold are less expensive as compared to machine moulded bricks. However, the cost of machine moulding is also higher than hand moulding because of the added cost of fuel even though the number of labor does not reduce. Table Moulded Bricks will generally have the Initials of company name Ex: SKB, ABW etc.

4.Drying–

Open air, hot floor, chamber, tunnel, etc are the drying methods adopted in various parts of the world. Most of the green bricks in India are sun-dried in open grounds for 3 days and then stacked and prepared for firing.

5.Firing–

Firing process consists of increasing the temperature of bricks progressively, holding it at a peak temperature (800 to 1100 degree Celsius) and then gradually cooling to ambient temperature. Initial slow heating ensures removal of residual moisture in green bricks. The high temperature causes the fusion of clay and other particles into a hard, durable and weather resistant product. Bricks are further allowed to cool and unloaded from the kiln.

6.Quality Control–

Sorted into grades, e.g. firsts, seconds, soft (re-burn) and sold.

Table Mould Brick Specifications:

Table Moulded bricks are made manually.
Edges are fine and Sharp,
Size - 8.8"x4"3" (L x B x H)Generally has a rough finish
Compression Strength should be less than 105 kg/sq cm
Water absorption should not exceed 20%.

Table Mould Bricks - Quality Check:

The two bricks should give a hard ringing sound when they are stuck together.

The bricks should have rectangular shapes with sharp corners and uniform colors.

The bricks should be free from cracks, chips and warpages, and organic matter.

First class bricks are suitable for construction of a building.

Third Party testing can be done at Materials Testing Laboratories for Compression Strength and Water Absorption.