As we all know, bricks are divided into red bricks and blue bricks. So, what are the differences between blue bricks and red bricks? Let's get to know it together!
1. Processing raw materials
The processing raw materials of red bricks are: shale, coal gangue, clay, etc., which are kneaded through a crushing process, and then mechanically or manually pressed. After they are dry, they are fired into bricks at a temperature of about 900 degrees Celsius.
Blue brick is a kind of sintered brick, and the raw material for firing it is generally clay. Then pour some water into the clay and squeeze it into shape. Then put it in a brick kiln and bake it to about 1,000 degrees Celsius, then cool it with cold water and you're done. The main purpose of its practical cold water cooling is to make the iron in the clay incompletely oxidized and to make it more water resistant.
2. Processing process
Red bricks are mainly fired through the bricks inside and out, and then the fire is turned off to let the kiln and bricks cool down. Because the air in the kiln is relatively smooth and there is a lot of oxygen, a very good oxidation atmosphere is formed. Eventually the iron element of the brick will be oxidized into iron trioxide, so its color is red.
The blue bricks are poured into the kiln directly after the bricks are fully fired, because the temperature in the kiln is very high at this time, and when water is taken in, it will immediately turn into water vapor, thereby achieving the effect of blocking air. And in the absence of oxygen, the ferric oxide in the brick will form ferrous oxide, which will eventually become a blue brick.
3. Look at the advantages and disadvantages
The advantages of blue bricks are strong durability, stronger than red bricks, better alkali resistance, etc., but the disadvantages are that the production cost is very high, the process is very complicated, the output is small, and mechanized production cannot be realized, so its price will be high. . The advantage of red brick is that the production process is simpler than that of blue brick, and it can also realize mechanized production, so its production efficiency is also very high and it is widely used. The disadvantage is that because red bricks are solid bricks, many farmland clays will be destroyed during production.