Introduction of ceramic tile production process
When purchasing ceramic tiles, many consumers must be curious about the
production process of ceramic tiles: how is it produced? China has a long
history and many brilliant achievements in ceramic production, so the
technologies of various enterprises are different. Next, We will introduce the ceramic
tile production process in detail.
1.
Raw material selection
Raw materials entering the warehouse shall be inspected, mainly including
sampling, cake beating and trial firing, physical property testing, chemical analysis
and other steps. The raw material inspector shall detect the moisture of the
samples; then, the tester will pulverize, beat cake and test burn the sample
according to the procedure, and test the whiteness, strength, water absorption
and other physical properties of the sample cake after the test burn. At the
same time, the tester will extract some powder from the pulverizing link for
chemical analysis to test whether the content of various chemical components in
the raw materials meet the process and technical requirements of the factory
2.
Powder preparation
The process of powder preparation includes batching, ball milling,
sifting, iron removal, mud homogenization, spray drying, powder making and
bunker stale.
Firstly, weigh the corresponding raw materials according to the process
formula (including water addition) (according to a certain proportion);
Then, the prepared raw materials are added into the ball mill for
grinding into slurry. The grinding medium pebble is prepared in the ball mill
according to the process requirements, so as to fully and evenly mixes all
kinds of block and coarse and fine raw materials after grinding and crushing.
On the one hand, it can promote the physicochemical reaction of the blank in
the firing process and reduce the firing temperature. On the other hand, it is
also conducive to the separation of impurities in the raw materials;
The slurry after ball milling meets the process quality requirements and
is put into the slurry tank. It shall be screened and iron removed on the way.
Screening is to remove coarse particles and some impurities that are not ground
during ball milling; Iron removal is because iron affects the whiteness of
ceramic tiles, and will form black spots, melting holes, impurities and other
defects on the surface of ceramic tiles, so it must go through multiple strict
iron removal;
After screening and iron removal, the mud shall be continuously stirred
and homogenized to make the mud composition more uniform, improve the mud flow
performance, increase the plasticity of the mud made in the later stage,
improve the green body strength, and reduce the cracking during forming and
firing.
After homogenization, the slurry is tested to meet the quality
requirements. It is transported to the spray tower by high-pressure
atomization, and powder particles are made by hot air drying provided by hot
blast stove. In the process of spray granulation, the control of moisture
content of powder is very important. The moisture content of powder and the
uniformity of moisture distribution in powder will directly affect the pressing
operation and the quality of brick.
The powder discharged from the spray tower, due to the difference in
moisture content inside and outside the granules, and the uneven moisture
content of each part of the powder, need to be conveyed to the silo to be worn
out, so as to make the moisture content of the powder more uniform. After the
powder is stale in the silo for 24 hours, it can be said that the blank
preparation process of ceramic tiles production is completed, and the prepared
powder will be sent to the next process through the conveyor belt.
3.
Press and Molding
The prepared powder will be sent to the press process. After being
distributed through the mold, a certain pressure will be applied to the powder,
so that the powder will be pressed into brick. It should be noted that in the
process of pressing into brick, the quality requirements of powder and the
correct operation process of the press must be guaranteed, otherwise the
quality of brick will be directly affected.
4.
Drying and printing
After pressing, the strength of the brick blank is very poor. Due to the
large moisture content of the brick blank, drying is to evaporate the free
water in the brick blank. On the one hand, it can improve the strength of the
brick body, reduce the damage of the brick body, and avoid the waste entering
the printing and firing process, resulting in unnecessary losses; On the other
hand, it can also avoid the billet cracking caused by the violent evaporation
of water when the brick with high moisture content is fired in the kiln( Printing is a
process for infiltrating polished bricks)
5.
Firing
The bricks are dried and then fired in a kiln. Before entering the kiln,
the brick blank shall be grouted first, mainly to prevent the brick blank from
sticking to the roller when it is softened in the high-temperature section of
the kiln. When entering the kiln for high-temperature calcinations, the maximum
calcinations temperature generally does not exceed 1250 ℃.
6.
Edging and polishing
The semi-finished ceramic tiles after firing should go through the steps
of grinding, scraping, polishing, post grinding and air drying, so as to become
the bright and flat exquisite ceramic tiles we see in the exhibition hall.
In the edge grinding process, it is strictly stipulated that the size and
diagonal of ceramic tiles must comply with the company's internal control
standards, with very high precision and high technical requirements for
operators.
Enter the polishing process. Polishing is divided into three steps: rough
polishing, medium polishing and fine polishing, that is, the grinding blocks
used for polishing are arranged from coarse to fine, and the milled ceramic
tile surface is gradually ground to have gloss and show the original texture of
the brick.
7. Waxing and
Package
It has very strict
control over product quality, and each branch has a quality supervision team to
control the product quality before leaving the factory.
Finally, the
moisture on the surface and bottom of the ceramic tile shall be air dried to
facilitate the waxing of the finished product, graded inspection and selection
of the finished product, packaging and warehousing.
2021 09/04