Clay brick manufacturing is a complex process which involves different facets of manufacturing and processes.
Clay brick manufacturing can be back dated back thousands of years. Very few products can compete with clay bricks on lifecycle cost, durability, thermal properties, strength and other technical specifications. Clay bricks have stood the test of time and will for many years to come.
Step 1: Mining
Materials are mined at Apollo Brick and added materials are imported to enhance the qualities of our product. Materials consist of clay, quartzite, shale, limonite, Mica and ouklip to name a few.
Step 2: Stockpiling - Weathering
All material required are stockpiled into certain recipes to get the outcome desired. Materials are left for months outside to Weather which enhances the properties of the clay.
Step 3: Crushing and Milling
Stockpiled material are Crushed via crushers and then Milled to ensure the correct particle size distribution is achieved for drying, firing, strength and other technical requirements. Water is also added after the final Milling process.
Step 4: Stockpiling - Souring
Crushed material is then stored for a few days and protected from the weather. This process is called souring whereby a chemical reaction happens and enhances the product before extrusion.
Step 5: Extrusion
This is the heart of the factory where the brick forming, shaping and sizing is done. This is by far the most complex process in the manufacturing and also the main key to the final quality of the brick.
The soured material is fed into a mixer and carbon is also added with the clay material. Water is added and they are mixed together. Vacuum pumps remove air from the material and simultaneously extrude the clay mixture into the shape which will be required for the final brick. The process is called stiff extrusion.
The extruded clay is cut into individual bricks and transported on various conveyors to Robots.
These robots use vacuum technology to pick up and place bricks onto pallets before being transported for open air drying. The unfired brick is referred to as a green brick.
Step 6: Open Air Drying
Open air drying is also referred to as hack line drying. This process requires then sun and mainly dry air to take out the moisture in the green brick so that it can be packed for firing.
Step 7: Packing and Firing
This is another key process in the manufacturing whereby bricks are packed into a clamp and coal is used on the base as a method to fire the bricks. The carbon which was added in the extrusion process then continues to keep the fire burning. This process is relatively uncontrollable once started and is left out to the elements of weather until finished burning. The clamp reaches temperatures as high as 1150 Degrees Celsius whereby a vitrification(heat fusion) process happens which forms the hardened fired bricks.
This process can take up to 14 days to complete depending on the clamp size and chemical properties.
Off packing & Sales
After the clamp has cooled down the bricks are selected and off packed according to specifications and aesthetic finish. The laboratory do various testing to ensure we comply to SABS requirements. Bricks are then loaded onto trucks and sold to various customers.