With a variety of designs and styles, ceramic tiles are able to provide a unique look to your home. What exactly is they made?
Dust pressing is the most popular method of fabrication, whereby giant hydraulic machines are used to press powdered substances. The tile is then given a dry strength, and warpage decreases when it is dried. Prior to firing, the pressed tile is also decorated using an engobe.
Manufacturing Process
In this beautiful video produced by Ceramic District we see excavators taking the natural raw materials for tile production, and then pouring them into large hoppers. The resulting clay minerals and other ingredients are mixed together, crushed and then incorporated into a powdered form, ready for the next stage. Through research and innovation, these materials can be used in conjunction with other mineral additions in ways that reduce the amount of energy required during the firing process.
The material is then measured and dosed before being wet milled in order to ensure homogeneity. Dry or wet grinding may be accomplished using a variety of milling machines, including ball mills or mullers. The material is reduced to a size that can be easily pressed.
Once the powdered mix is created, it has to be kneaded in order to get rid of air and form an even, dense consistency. This is crucial to create tiles with an even, smooth surface that resists scratching and stains.
The most commonly used method for fabrication is dust pressing, where massive hydraulic presses are used to press the dry tile powder into flat tiles that can be as big as a meters square. This prevents shrinkage when drying, and so the final product will be flat and true. Glazes and engobes are applied to the tiles prior to the final firing.
Glazed Tile Production
The primary ingredients used in the production of the glazed ceramic tiles is clay minerals derived from the earth, along with other minerals that are naturally occurring, such as feldspar to lower the firing temperature (Ceramic Research Company). Clay is made up of an aluminium silicate hydrous, with a plasticity which allows it to be molded and shaped to create the desired shape. The pigments and glaze are second-most important raw materials that determine the color, pattern and style.
The manufacturing of glazed tiles starts with the initial grinding of the raw materials which can be done using the muller or roller mill which uses a squeezing motion between steel plates or a rotating motion between steel cones to reduce larger lumps to smaller particles. The raw materials are dried to remove any moisture that remains.
Once the body slip is dried out the next step is to apply a glaze the tile’s surface. The glaze is the liquid mix made of a glass-based derivative called frit, and dyes that are colored. The glaze fuses with the top layer of the tile in a high-temperature kiln in the ceramic tile firing process.
To ensure the uniformity and high quality of the glazed tiles they have to go through a variety of other procedures. It has to be polished to a sheen to provide a beautiful finish and then carefully inspected for any flaws before being packed for distribution.
Roller Kiln Tile Firing
While the super hero Peter Parker gets his powers from a radioactive spider and the Green Lantern gets an earring from a dying star Ceramic tiles are powered by clay which is formed by firing, then glazed. While various processes, raw materials and manufacturing techniques create various types of tiles all have one common feature: the porosity (water absorption) of their unglazed backs.
After some dust pressing in huge hydraulic presses and pre-firing, large batches are loaded into huge rolling kilns. These kilns for rollers have revolutionized the process of firing and eliminating warping due to shrinkage. It was actually the technology in the kilns that made it possible for tile to go from wall tile only to floors and walls in homes and commercial buildings, hotels and other areas.
The tile is subjected to an extreme temperature treatment in the kiln. If the tile is to be glazed, it is put through a glaze phase (step 4). This involves putting a thin coating of liquid glaze the tiles, and drying them under extreme temperatures in a controlled atmosphere.
Kilns can either be heated using natural gas, electricity or oil. Based on the fuel used and the type of fuel, the temperature inside the kiln can reach as high as 2,500 degrees Fahrenheit. The manufacturer can use conveyor belts to move tiles in the kiln, which will help keep its shape tiles while it’s being heated.
Clay Preparation for Tiles
The initial step is to mine clay minerals, then transform them into sand. The sands are then blended with natural minerals like feldspar, which helps lower the temperature of firing as well as chemical additives for shaping. The mixture is crushed or ground to create smaller lumps. This can be done using a muller or hammer mills. Crushing is messy and difficult task since it involves the use of steel hammers, which could damage or even destroy the terra cotta clay.
The next step in ceramic tile manufacturing is to get the clay with the proper texture for creating tiles. First, the technicians need to sketch and sketch the shape they want for a particular tile product. Sketches and template can help make the gach the op tuong process easier especially when it comes to large-scale tiles used for home and artistic projects.
To remove air bubbles, the clay slabs need to be shaped, wedged and then shaped to the dimensions you want. After the tiles are formed, they must dry completely between drywall sheets, to prevent warpage. The most challenging aspect of the process of manufacturing is this step. Technicians are constantly fighting against pinholes. A single pinhole can ruin the entire production. Making sure the tiles are flat during drying and the kiln firing is also very important.
When the tiles are ready they can be painted. The glaze can be poured on or spray-applied onto the tiles. Glaze can be made with glass derivatives or colored dyes. Ceramic tiles are fired as the final stage of the process. The kiln is heated up to about 2000 degrees Fahrenheit.
