This quick tour is for a brief and non-technical tour designed to provide some basic and general details on how tile is made.
Keeping in mind that tile itself is basically baked dirt, the overall process hasn't changed much in the last century, and some of the process has shortened the firing time and made the tile harder and more durable or more pleasing to the eye. But the overall process still consists of taking clays refining them drying, pressing or extruding, decorating/glazing and baking in ovens known as kilns.
Here we will take you through a tour which will briefly show some of the process, we have omitted allot of technical, prep and packaging photo's, just to give you a sense of the process.
This photo shows the glaze as it is stored in bags until the time is to be blended, Glaze is called "Frit" which is a type of glass and is blended and applied in many ways.
Here we are showing a ball mill. Large drums are used with Aluminum balls varying in size from 6″ around in some cases to ˝" are inside the drum and The tiles body product the "clay or the Glaze Frit can be tumbled and prepared individually until the time it is ready for the next process. Note man in back of photo to get an idea of size of the ball mill.
After the body or clay is prepped a drying needs to take place to remove moisture for the forming of the tile, in most factories a "Spray Dryer" is used, this is best described as a large 4 or 5 story metal structure which looks like a funnel. The wet clay is shot under great pressure up into the spray dryer from near the bottom, and as it is settling back down to the bottom it is dried by hot air that is flowing in the spray dryer. When the clay has settled to the bottom via gravity it is at desirable moisture content for forming and has formed into a small pellet not unlike a small BB.
A conveyor system will transport the clay to the next step.
After a proper blending and drying the clay runs to the press area where the clay is flowed into a mold and pressed under many hundreds of tons of pressure to form a "Greenware" tile body. A press can be for a small trim tile or a massive 24″x24″ tile. Shown here are two shots one of a single press and one of an entire press line.
Once leaving the press in some factories the greenware goes to a holding area automatically until the body is ready for glaze, normally the holding time is only minutes long.
After pressing and before firing the glazing process begins in most factories, (although some factories still fire the basic clay without glaze and create a "Bisque" or unglazed body for later firing or they sell the bisque to another company who may only glaze in their factory for specialized reasons), in most factories they quickly move to the glaze process before firing.
The glaze has been blended and is ready for the application to the tile by one many types of methods, or many various application methods can be applied to a single tile, known a "stages", some tiles can have as many as 20 application stages.
The picture here shows a full glaze line with many stages
This is a photo of a spray glaze line open for cleaning for the next glaze color.
A rotating glaze brush applicator, the glaze is applied and then brushed to create a "Faux" affect in some cases.
A glaze line in the glazing process, the glaze is very liquid, it is pumped form the bottom of the drum and sprayed onto the tile then any glaze not adhering to the tile is flowed back into the drum via the tube you can see for processing again through the pump.
After glazing the process of firing takes place. It is really impossible to show you the scope of this process. These gas kilns used today can be as long as a football field and fire at 2200 degrees. The tiles are automatically loaded into the throat of the kiln and a sent down a long path through the kiln at, warm up, full temperature and cool down, until the tiles can be sorted and boxed without leaving the production line. This process can take as little as 40 minutes. The tiles roll down the line on ceramic rollers made of "refractory" material.
This shot shows a full shot of a kiln, the refractory rollers appear as the white stripe down the middle.
A closer shot only showing middle to back of a kiln.
A photo here shows a final cool down area before sorting takes place.
The final process before automated boxing shows a "master shade table". The human element comes into play here, the tiles are measured during the process for square and size by lasers, color and shading can be checked with light measuring devices also but all tiles must pass by a human for the final look.
This photo shows a lighted slant table where tiles of acceptable shade (master samples) are placed in front of a person who will check as the tiles go by for seconds or rejects, and are marked accordingly.
A typical floor tile plant making 250,000 square feet per week can employ only 14 people per shift, making this a very automated process compared to factories 10-20 years ago.
If you found this article helpful, let us know in the comment section below. Also, feel free to share it by clicking the share buttons below. Want us to cover another topic related to grouting products and techniques? If so, then like us, follow us, and post to any of our social media profiles the topic you'd like us to discuss: Facebook TheTileDoctor
, Instagram @thetiledoctor
, Twitter @thetiledoctor
, and Google+ thetiledoctor