In the world of kilns, high alumina bricks play a very important role. If you are engaged in the design, construction, operation and maintenance, and management of high-temperature kilns in kiln companies, steel plants or cement plants, or if you are a corporate decision maker, purchaser, or technical R&D personnel in related industries, then choosing high-alumina bricks is definitely an important part of your work.
(I) Kiln top position
The kiln top has to withstand high temperatures and gas erosion in the furnace. This requires high-alumina bricks to have a very high refractoriness, at least above 1750℃. And the thermal shock stability must also be good, because the temperature of the kiln top changes frequently. For example, in the kiln top of a glass kiln, the temperature is sometimes high and sometimes low. If the high alumina fire bricks have poor thermal shock stability, they will easily crack and damage. Therefore, in the kiln top position, high-alumina bricks with high alumina content and stable crystal structure should be selected, such as corundum alumina bricks. (Insert a schematic diagram of the kiln roof where high-alumina bricks are used, marked: kiln roof position, high-alumina brick laying method)
(II) Kiln wall
The kiln wall must be resistant to erosion. Because the kiln wall is in contact with the materials and gases in the furnace, it is easy to be eroded. At this time, you have to choose high alumina bricks with good slag resistance. For example, in the blast furnace kiln wall of a steel plant, the molten iron and slag erode the kiln wall severely, so you have to use high-alumina bricks containing special ingredients that can resist these erosions. Generally speaking, sillimanite high-alumina bricks perform well in this regard, and they can effectively resist the erosion of molten iron and slag.
(III) Kiln bottom
The kiln bottom has to bear the weight of the materials in the kiln, so the load softening temperature of the high alumina brick must be high and the compressive strength must be high. For example, at the bottom of the rotary kiln in a cement plant, a large amount of cement clinker passes through it. If the high-alumina bricks do not have enough compressive strength, they will be easily crushed. At this time, you have to choose high-alumina bricks with high density and dense structure to ensure the stability of the kiln bottom.
Steps to select high-alumina bricks. Learn these four steps to select high-quality high aluminum bricks:
(I) Understand the needs of the kiln
First, find out what your kiln is used for. You must understand the working temperature, pressure, and material properties. For example, the converter kiln used for steelmaking and the kiln used to fire ceramics must have different needs. Only by understanding the needs of the kiln can you select high-alumina bricks in a targeted manner.
(II) Select the type of high alumina refractory brick
According to the needs of different parts of the kiln, such as the different requirements of the kiln top, kiln wall, and kiln bottom mentioned just now, select the appropriate type of high-alumina bricks. For example, choose corundum for the kiln top, sillimanite for the kiln wall, and high-density for the kiln bottom.
(III) Investigate suppliers
When selecting high alumina bricks, suppliers are also very important. Find a supplier with a good reputation, advanced production technology, and guaranteed quality. You can go to the supplier's factory to understand their production process and quality control system. You can also ask your peers to see which supplier is reliable.
(IV) Compare prices and quality
Compare the prices of different suppliers while ensuring quality. Don't just go for cheap, the quality is not up to standard, the later maintenance cost will be higher. You need to find high-alumina bricks with high cost performance.
