Clay bricks are made by mixing clay with water and an aggregate like sand, which keeps it from shrinking and provides mass. Unlike conventional clay brick, which is fired in kilns, sand-lime brick is formed when the component materials bond together through chemical reactions occurring when a wet brick is dried by heat and pressure. Modern brick manufacturers use fired clay bricks formed by one of three processes: soft-matter, dry-press, or extrusion.
Dry-Pressed Bricks – The dry-pressing technique is similar to the soft-mud molding technique, but begins with a much thicker mix of clay, thus producing more precise, more angular bricks. Before a brick is fired, it must dry out, removing all moisture that is in the moist, sanded clay. In the burning process, dry bricks are burned in a clamp (smaller sizes) or furnaces (larger sizes) up to certain degrees of heat. In this phase, bricks gain toughness and durability, hence this is an important phase of brick making.
The process of firing can be done in two ways depending on the size of the project. If the brick production is in a smaller size and also the manpower is cheaper, then we can opt for manual firing. The Process to Make Bricks From Clay Making bricks out of clay involves preparing the clay, shaping it, then drying it, and then burning it. The process of producing sun-dried or non-burnt bricks involves the preparation of clay, shaping, and drying using natural heat.
The clay gained its plasticity, and now clay was ready to shape. In the burning process, prepared clay was formed into the shapes of bricks (usually rectangular). This process is similar to the ground-molding process, but here bricks are formed in the form of a mold in the form of a table measuring 2m by 1m.
The inside of the mold is usually coated with sand, providing desired texture and making it easier to lift molded bricks out of the mold. The walls and the roof are paved with a mix of sand, clay, and water, to trap the heat; the bricks are placed closely together on the roof, with openings to allow air circulation, to draw heat upwards through the bricks. The drying courtyard is also set at higher levels than normal soil to the protection of the bricks from rainwater.
The brick-making process requires basic raw materials such as clay, which is later crushed down to particles, and water, which forms a paste. Bricks are typically made from clay, with additional materials which vary from brick to brick. In the modern age, several different materials have been developed which are practical alternatives to clay bricks, regarding costs, installation simplicity, and insulating properties. In addition to building, clay brick has been used for paving, but has proven to be incapable of holding up under load in the era of motor vehicles.
Properly, the term brick refers to a unit composed of dried clay but is also used now unofficially to refer to other chemically-cured building blocks. The term brick refers to smaller units of construction materials, usually made from fired clay, which is held together by mortar, a bonding agent consisting of cement, sand, and water. These types of brick are samples of the general materials used in brick making, and researchers frequently experiment by changing levels of clay, sand, lime, fly ash, cement, and other materials within a given brick to find combinations that have optimal properties.
Clay is still a major material for bricks, but sand and lime, cement, and fly ash are also common. Some clays need to have some added sand or grist (pre-ground, pre-fired materials, like crushed bricks).
All of the structural clay tiles are produced in this process, as is an increased proportion of the bricks. Mark B. Mahoney/Sioux City Brick & Tile Company, Des Moines, IA In the older brick-making process, a process called sand-and-sand, far more water was used, and the mixture was placed into wooden molds to shape the desired sizes. When required hardness is obtained, clay is placed into molds and hard, well-shaped bricks are produced.
These are called Pressed Bricks, these do not need drying, and can be sent straight into a burning process. Fly Ash Bricks are lighter in weight compared with cement bricks and clay bricks, because of lower absorption rates, able to resist both heat and water very well. Calcium-silicate bricks are made instead of clay, using lime that bonds silicate materials.
Lightweight bricks (also called lightweight blocks) are made with expanded clay aggregate. Concrete bricks are better than clay bricks, and they can easily be manufactured with machines at any building site, reducing the amount of mortar required during manufacturing, and thus making them lighter.
When used for clay bricks, the color depth is considered to be superb, with a superior surface finish. The color of baked clay bricks is affected by the chemical and mineral contents of the raw materials, firing temperature, and kiln atmosphere. Natural clay minerals, including kaolin and shale, form the basic brick material. Small amounts of manganese, barium, and other additives are mixed in with natural clay minerals to create a variety of shades, while barium carbonate is used to increase brick’s chemical tolerances to elements.
Manufactured Bricks — These bricks begin with unprocessed clay, preferably mixed with 25%-30% sand for reduced shrinkage. Now, these unprocessed bricks are ready for the drying process. Drying clay machines are time-saving machines.
Unfired bricks, also known as clay bricks, are made of moist, clay-containing soil mixed with straw or a similar binding agent. There are various types of bricks, including light bricks or blocks, generally made of expanded clay, fired bricks are considered one of the strongest construction materials, while air-dried bricks or mudbricks are the oldest bricks used in construction.