When many users choose firebricks, there are many different colors, which leads to no accurate selection marks, so in order to help users to choose the right brick, the next color selection criteria are introduced, in order to better meet the needs of users.

The color of clay firebrick is generally light yellow or brownish yellow or dark yellow, and the surface of the brick will have brown or black spots, which are generally formed by impurities in the refractory raw materials after high temperature firing. The color of high aluminum refractory brick is mainly beige, even a little white, most of the refractory brick products made of magnesium, graphite and silicon carbide are bluish black. Corundum and mullite are mostly white, and high-aluminum refractory bricks are often used to judge the quality of bricks by color. But in fact, the same indicator content of the firebrick color will be inconsistent.

Because there are many factors that affect the color of firebricks.

(1) The brick is improperly packaged in the kiln car, and the uneven sparness leads to the flame cannot evenly heat all the brick, resulting in the uneven heating of the brick during preheating, and the moisture of the refractory brick cannot be excluded into the firing zone, resulting in different colors of some bricks.

(2) The processing temperature of refractory brick is not well controlled, resulting in excessive fluctuation of firing temperature, which will make some parking Spaces high temperature and some parking Spaces low temperature.

(3) The smoke exhaust pull is too large, so that when the flame can not reach the top of the kiln, it is pulled out of the high temperature belt in the horizontal direction, causing the temperature difference between the top and the bottom to be too large, and the temperature difference of the fired refractory brick can reach 50 degrees, so that sometimes the lower part of the product sticks and deforms to produce waste products, while the upper part still does not reach the sintering temperature.

In addition to the process influence in the firing process, after the refractory brick comes out of the kiln, with the influence of storage time and storage environment, some chemical reactions will slowly occur on the surface, ultimately leading to the color difference of the refractory brick.