How Ceramic & Porcelain Tile are baked in Kiln : Tiles from India
The ceramic or porcelain tile is made with mainly five parts :
Raw material mixing & processing
Printing & Glazing (if required)
Rectification, Polishing (if required) & Packing
The firing part is one of the most critical parts of the ceramic & porcelain tile production. For the firing or baking or drying or hardening of tile, a kiln is used in the tile production line. First the raw material is mixed & processed and fed into the hydraulic press to produce the biscuit tile. This biscuit tile is very brittle and just the raw materials highly compressed and dense to give the size and shape required.
Once the biscuit tile is produced, it passes through a dryer machine. Dryer in the ceramic & porcelain tile production are of two types : vertical or horizontal. The purpose of the dryer is to reduce the moisture content from the biscuit tile. After the tile is dry, the tile goes through glazing if required and then the printing is done on it through various ways, the most acceptable method nowadays is the digital printing machine.
Now when the tile is pressed, dried and printed, the tile needs to be baked in order to make it strong physically, to make it waterproof and chemical resistant.
Kiln is an oven which produces the high temperature required for the baking of the biscuit tile. In ceramic and porcelain tile production from india, the most prominent kiln used is Tunnel Kiln also known as Continuous Kiln. A typical kiln in the production of ceramic and porcelain tile from India ranges between 70 mtrs long upto 400 mtrs long. The width depends on the size and the production capacity of the line similarly.
The tile is entered into the kiln with the help of special kiln rollers. The temperature increases gradually from 50 degrees celcius to upto 1200 degree celsius. For porcelain tile production from India, the temperature of kiln goes upto 1200 degree celsius. For the ceramic tile production from India, the temperature of kiln goes up to 1050 degree celsius. So it depends on the type of body, for example ceramic tile is low on strength as compared to porcelain tile. And water absorption of ceramic tile is in range of 12-13% where as in the porcelain tile from india the water absorption is as low as 0.02% (Note : The ISO certified rating for the water absorption in porcelain tile is less than 0.5%)
Generally the kilns which are used for large production capacities at our plants are from SACMI, Italy but there are also other italian and chinese companies who are major players in ceramic and porcelain kiln makers. We also make custom kilns at our ceramic production plants, for example one of our kilns at our subway plant is made in india because the production capacity required is comparatively less and we wanted a custom made kiln to fit into our production line and to optimise the production capacity and quality.
Hope this article helped you in learning a bit or two about the firing part in the tile production. For our range in ceramic tile & porcelain tile, you visit our website.
Also if you have any comments or questions in mind to ask, feel free to email us.