The procedure needed to produce bricks begins with a digger extracting clay from the ground. This is then placed on a metal grid and the finer particles drop onto a conveyor belt. Sand and water is added to the clay. In terms of the shape of the brick, two options are possible. The bricks are either shaped using a rectangle mould with a hollow centre or cut into blocks using a wire cutter.
The bricks are left to dry in an oven for 1 or 2 days. The dry bricks are then placed in a kiln and two different temperatures are applied, moderate heat (200 – 980 degrees Celsius) followed by high heat (870 – 1,300 degrees Celsius). The heated bricks are then placed in a cooling chamber for 48 – 72 hours. The bricks are then ready to be packed and delivered.
To make bricks, clay, sand and water are needed. The process which requires drying, heating and cooling lasts less than a week.
Question taken from Richmond Practice Tests for IELTS Student's book p.56