01. Frontier Overview
The quality of high alumina bricks with the same aluminum content is not necessarily the same.
02. Aluminum content for judging quality
Because the aluminum content of high-alumina bricks is only one of the indicators for judging the quality. The same aluminum content depends on the bulk density. The higher the bulk density, the stronger the compactness and the higher the wear resistance; it also depends on the size and Whether there are internal cracks; the size can only be regarded as qualified if it is increased or shortened according to the national standard. There are also cracks, depending on whether it is a layer crack or a surface crack.
If its surface is just a network of cracks, it is caused by too high temperature or too fast drying during the drying process, which generally affects the inner use. unusable.
03. Description of softening temperature
Although the aluminum content is the main indicator, the load softening temperature of the brick is also very important. If the temperature during sintering is high, it means that the internal quality of the raw material is good and dense, and the load softening temperature is high. If the sintering temperature is low, the softening temperature under load is low. Bulk density and softening temperature under load are the two indicators that can best prove its quality.
Under normal circumstances, the softening temperature under load cannot be seen or weighed, while the bulk density is the most intuitive way to measure its compactness, that is, the most direct way to judge the internal quality. The heavier the refractory brick, the higher the bulk density.
04. Determine whether the quality is good or not
And some users who don’t know the situation very well often judge the quality only by the color and aluminum content, which is unscientific. Some of the colors are particularly nice, and very even, and the sizes are reasonable. But the weight is light, which means that this batch of bricks uses raw aluminum powder to adjust the color of the bricks, and the internal quality cannot be compared with cooked powder. Because raw aluminum powder is added to the brick, the color is good-looking, but when used at high temperature, the wear resistance and high temperature resistance are not as good as the high-alumina brick produced by adding clinker.
Therefore, to judge whether the quality of high alumina bricks is good or not, it must be judged by the load softening temperature of the bulk density.