1. Frontier overview
Identifying the quality and level of high alumina brick can be identified from three aspects: appearance, body density, and laboratory test.
2. Identification from appearance and color
First of all, identify from appearance color: if the color of high alumina brick is yellowish, it is a third-grade high alumina brick. If the color is yellowish white, it is proven to be a second-grade high alumina brick. If the color is white, it is proven to be the first-grade high alumina brick. If the color appearance of these three is not smooth or did not appear crystal phase, indicating that the sintering temperature is low, the strength is not good when using.
In addition to seeing the high alumina brick surface has no black spot or large burned melt, if there is a black spot because the raw material iron content is too high, the use of holes will appear, affecting the role of life. Also look at the surface of high alumina brick is flat. If the surface is not flat, because the sintering legs burned, there are large bricks pressed above, the surface is not flat. This also affects the masonry when the staggered layer, in the use of late, will also affect the service life.
3. Identify the size
Next, to look at the size, size is to use the ruler, if the high alumina brick length, width, and thickness greater than 2mm, indicating that the mold put the ruler large, may also be the reason for raw materials, sintering up the ruler, if the size of uniform greater than 3mm or more. This size of high alumina brick is not available.
4. From the bulk density to see the quality of high alumina brick
Can also see from the bulk density of high alumina brick quality. The test method is to use the electronic scale to weigh out the single brick, then the high alumina brick length, width, height, or size of the head to measure out the size, and then calculate the volume, with the weight divided by the volume, is the specific gravity of high alumina brick. If the specific gravity is lower than 2.3, it is proven to be a third-grade high alumina brick, if the bulk density is greater than 2.3, it is a second-grade high alumina brick, if the bulk density is more than 2.45, it is the first-grade high alumina brick.
Refractory brick aluminum content, if the aluminum content of 55%, is the third-grade high alumina brick, if it is 65%, it is the second-grade high alumina brick, if it is 75% is the first-grade high alumina brick. However, the aluminum content is only known after chemical testing. Visually can not be seen.
There are also refractory brick strength, thermal shock, and refired line changes that are also to go through the physical chemistry to know, the naked eye is not visible.
Refractory bricks of the load softening temperature are also the most important ones in the use of the process. This has two methods to identify, one is to see the sintering temperature of high alumina brick, if the sintering temperature is 1380, then the load is about 1400. If the sintering temperature is 1450, then the load temperature is around 1480. But the load softening temperature if you want to be more accurate, then you have to go through to do the test.
In general, the quality of high alumina brick is from the color, size shrinkage, and body density of these three intuitive methods to judge. Of course, if the user requires other indicators, it is necessary to go through the test to know.