Brick Manufacturing – How is it Made

how-to-make-bricks

Bricks are small units of material that are generally made from fired clay and secured with a bonding agent made with water, sand and cement. Bricks have many advantages compared to other building materials currently available and not only do they resist fire, but also withstand corrosion and retain heat. On top of that, bricks also require minimum maintenance and last for a very long time.

Making bricks

making-bricks
History book illustration of ancient Egyption brick-making, colorized for this file. Source – A General History for Colleges and High schools by P. V. N. Myers, published in 1890

In order to make bricks, raw materials need to first of all be crushed and then ground using a jaw crusher. There are several methods used to form the ingredients, so for instance, when it comes to the extrusion method (the most popular for making bricks), the ingredients are mixed together with H2O that is first of all passed through a special chamber that removes the air from it. This helps prevent cracking. While vinyl, plaster, aluminum, stucco and also wood are very notable competitors of bricks, they can’t really compete with it because they cost up to 175% more than bricks.

But if you don’t really like bricks or don’t want to use them for your specific project, then you can rest assured since there are many other building materials you can consider, including concrete masonry, cmu, artificial stone, stone, glass and precast concrete panels.

  • Raw Materials

The main body of the brick is made up by shale and kaolin. In order to create different shades, small amounts of barium, manganese, but also many other additives are blended with the clear, while the brick’s chemical resistance to the elements can be improved by mixing in barium carbonate.

  • Manufacturing the brick

To produce bricks, the raw materials need to first of all be crushed and grounded in a jaw crusher and separator. After that, the specific blend for each batch is chosen and filtered prior to being sent on to 1 of 3 brick shaping processes, including pressing, molding and extrusion. After the bricks are made, they’re going to be dried properly in order to prevent cracking during the firing process. In the last stage, they’re stacked automatically wrapped using steel bands and then padded.

Here is some version ob brick manufacturing process in India

  • Combining, sizing and grinding raw materials

Each ingredient needs to first of all be conveyed to a separator where the oversized material will be properly removed. The particles will then be crushed to smaller pieces by the jaw crusher. The correctly sized material will be sent to storage silos, while the larger material is going to go into a hammer mill.

  • Extrusion

This is the most common way to make bricks and it involves feeding pulverized material and water into 1 end of a pug mill. This is where the material will be cut through and folded together. After that, the blend will go into an extruded which consists of 2 chambers: one of them uses a vacuum to remove air from the ground clay while the second one compacts the material in order for the auger to easily extrude it through the die.

  • Brick chamfering

At this point the bricks are going to be indented. Depending on the type of chamfering machine used, it can produce as many as twenty thousand units per hour.

  • Coating

When the brick is extruded the manufacturer can choose to coat it in sand, but this depends on how soft or hard the extruded material is. For instance, in order to coat soft material, a continuous vibrating feeder is used, but when it comes to textured material, the coating needs to be rolled on or brushed.

  • Drying

The brick cannot be fired until it’s properly dried to remove moisture. If there is still moisture left in the brick during firing, then the brick is undoubtedly going to crack.

drying-bricks

  • Firing

After they are dried, the bricks are going to be loaded onto cars, fired and cooled down.

  • Setting and Packaging

The bricks at this point are already fired and cooled down, so they’re going to be unloaded from the kiln and placed in stacks. The stacks are wrapped in steel bands and fitted with plastic strips in order to protect the corners.

  • Quality Control

After they’re manufactured, bricks are checked for mechanical strength, density and physical dimensions in order to make sure they fall into the required quality standards. The truth is that many quality control tests nowadays aren’t as effective as they should be and while they do work in laboratories, in the real world there is much room left for improvement. That is why in order to address this problem, a lot of manufacturers have started to develop their own tests that ensure they can easily separate poor quality bricks from the top quality ones.

  • The Future

The use of bricks is steady and industries around the world use between 7 to 9 billion of them a year. Compared to the amount used in the early nineteen hundreds (around fifteen billion a year), this is about 50% less, but that’s to be expected.

Brick manufacturers though aren’t really happy about the number and that is why they are considering many efforts in order to increase demand in new markets and also improve productivity and quality. Fuel efficiency has also increased a lot and by the year 2025 it is a expected that a large number of brick manufacturers are going to fire their bricks with solar energy.

On the other hand, even if there will be a continued and increased demand of bricks, the industry will need to comply with environmental regulations, especially when it comes to fluorine emissions. If you don’t know what fluorine is, you should know that this is a dangerous byproduct that results from the process of making bricks.

If humans are exposed to it for long period of time, it can cause changes in bones and teeth, digestive problems, but also liver and kidney damage. The damage of fluorine can be reduced though, but only if manufacturers install scrubbers. However, these are pretty expensive and not every brick manufacturer wants to use them.

Currently, a lot of brick manufacturers in the US are trying to reduce their emissions, but there are also manufacturers that won’t be able to comply with these standards. As a result, many of them are faced with the possibility of going out of business which is only going to cause the worldwide brickmaking industry to shrink.

Article by Echevarria Mendez

I've been working with concrete all my life. It's a material to admire for its strength and beauty.