Tecnodieci Alumina Bilya;
Alumina ball is used in ceramic and other raw material grinding mills and generally contains 92% Alumina.
It is a hard, very low-wear ceramic material. Alumina ball has high abrasion and impact resistance.
It is achieved by the purity of the raw materials used, the production process and the high firing degree.
However, since the percentage of wear cannot be determined visually, it must be subjected to a comprehensive wear test in a laboratory. The most important feature to be considered is that since it is a solid material, due to insufficient firing temperature and time, although the surface wear is within the standards, increased wear can be seen when the inner areas are reached.
For this reason, the most correct method is to fill the mill with the same batch of standard distribution balls and test the operation.
One of the most important factors to consider here is that different brands of balls are mixed in the same mill.
Because both balls have %. Even if they are 92 gauge, the balls may corrode each other as their densities may be different due to their processes.
There are two types of balls: dry and wet grinding balls. Therefore, if you do not choose the ball suitable for your grinding,
wear will be higher.
Ball sizes are generally between 5 - 90 mm. Appropriate balls should be selected according to the place of use and shape. In ceramic raw material grinding, 30-40-50-60 mm balls are generally used from the beginning to the mill. Then, when there is constant wear, the largest size of additional balls is selected.
Practically, 40% of the mill volume is ball, 40% raw material and water, the remaining 20% is left as agitation.
and ball selection; if the material you are going to grind is soft, a medium sized ball should be used, if you want a hard material, a larger ball (for crushing) should be used.
When purchasing balls, you can check the % water absorption value of the ball specified by the manufacturer. Practically, the lower the water absorption percentage, the less ball wear.
and finally, you can empty the mill balls on the ground at certain periods, sort them with a sieve system and throw them back into the mill, or you can attach a filter cover to the filling cap of the mill with the diameter of the ball you want to fall and fill the mill with water.
You can turn it empty and throw out the small balls inside.
Alumina balls or Alubit balls are round balls used to reduce the grain sizes (grind) of materials in the mill by crushing them.
Alumina balls; It contains 50% to 99% Alumina in its formulation and its density varies from 2.7 to 3.8.
The balls to be used in dry and wet grinding differ. Therefore, if your system is dry grinding, you should definitely prefer balls produced for dry grinding, otherwise your ball consumption will be too much.
In addition, the ball diameters in the mill should vary according to the hardness and grain size of the raw materials you want to grind. For example, in Frit-heavy formulation,
larger balls are preferred for easier crushing, while smaller ball distributions should be preferred in grinding softer mixtures such as Engob.
There are two ways to produce balls; the first is by casting the ground formulation, and the other is by baking the prepared formulation at 1400-1450 C by pressing it.
It is produced in sizes from 5 mm to 100 mm.
How to use alumina balls;
Alumina balls are added to at least 3 different diameters (for example 30-40-60 mm) to correspond to 40% of your mill volume, and when there is a decrease due to wear during production, the amount that decreases from the largest ball is added continuously.
What to consider when buying alumina balls;
Alumina balls are not produced in Turkey. For this reason, you can import them from importing companies or directly from the manufacturer yourself. The most important point here is of course the %Al203 amount of the ball you will buy and other parameters are very important because they are the factors that determine the price of the ball. Most of the balls used in the ceramic sector in Turkey are 90-92% Al2O3 balls. However, since it is not possible to understand this by eye, you can get an idea by asking the company for the technical features, density and water absorption value of the ball.
How is the ball quality control test done;
Preferably, balls of different sizes (4-5 pieces min.) are first weighed and placed in the roller mill. Enough corundum raw material is added to the volume of the mill to make it shake (preferably 100-120 mic corundum) and rotated together 24 hours a day, 7 days a week. At the end of a week, the stones are cleaned from corundum with the help of a brush and weighed again and their wear is calculated as a percentage.
Important note;
The most important point to be considered here is that since the balls are baked according to the heat and time factors like ceramics, the wear on the upper surface of the ball and the subsequent layers may differ from 5 mm. This reduces the reliability of the wear tests on the balls. The most reliable method in this regard is to empty all the old brand balls in your mill under your operating conditions and add new balls (the purpose of emptying the old balls is that since there may be a density difference in the balls of two different brands, the balls are likely to wear each other out) and test them by making the same production you produced before.
