How to Distinguish the Quality of High Alumina Bricks

The quality of high alumina bricks is mainly distinguished by their appearance, physical and chemical indicators, sound, weight, etc. This is what we need to consider when purchasing high alumina bricks. Next, the editor will help you to understand.

1. Appearance

The surface of high-alumina bricks is smooth to the naked eye, beige in color, flat on all sides, with no corner cracks, and few black spots. The color will vary depending on the alumina content. The higher the alumina content, the color will be whiter. The black spots on the surface of high alumina bricks are mainly formed during the calcining process of iron oxide. If the black spots appear in a large area, it indicates that the iron oxide content of the brick is too high, which indicates that there is a problem with its proportion. , will affect the service life of the brick.

2. Sound

When two bricks are struck, the sound of high-quality high-alumina bricks will be crisp and not dull.

3. Weight

According to the weight specification, the general weight of first-grade high alumina bricks is about 4.4 kg, the weight of second-grade high alumina bricks is about 4.0 kg, the weight of third-grade high alumina bricks is about 3.7 kg, and the weight of special-grade high alumina bricks is about 4.8 kg. A fluctuation of 0.1-0.2 kilograms is within the normal error range. In addition to the above common weights, the weight of high-alumina bricks will also vary with the alumina content of the bricks. When distinguishing between first-level, second-level, and third-level, when buying special high alumina bricks, it still depends on the alumina content. Of course, there is a difference in weight between them.

4. Physical and chemical indicators

The indicator that best reflects the quality of high-alumina bricks is its physical and chemical indicators, such as the strength, volume density, refire line change, load softening degree, etc. of refractory bricks. Generally speaking, first-grade, second-grade, third-grade, and special grades are high. There are some differences in the physical and chemical indicators of aluminum bricks, and they must be used on different occasions during use.

The quality of high-alumina bricks affects the service life of high-temperature kilns, so you must choose carefully when purchasing, and using different high-alumina bricks in different parts because the temperature of each part in the high-temperature kiln is Different types of high alumina bricks must be selected according to different temperatures during use, to ensure long-term stable use of high-temperature kilns.