Refractory precast and refractory bricks are two different products. Although they both have different dimensions, they are different product structures. Precast blocks belong to the amorphous series, while refractory bricks belong to the shaped products.
The pre cast block is made by mixing refractory castables in a mixer, adding water and mixing evenly and then pouring them into various molds prepared in advance. Then, we use a vibrating rod or a vibrating table to vibrate it into shape. Finally, we demoed the refractory castable in the mold after it hardened for 24 hours.
Manufacturers can make refractory bricks by high-pressure molding and high-temperature sintering. The quality of refractory bricks produced from different grades of raw materials is different. Then, we use a press to high-pressure mold it. After that, we dry it and sinter at a high temperature of more than 1400℃(2552℉).
The appearance of pre cast block is gray-black or cement color. If it is white corundum castable, the color is gray-white. If it is chrome corundum castable, the color is green. However, the surface of all precast bricks is slightly rough and not smooth.
The appearance of refractory bricks is neat and delicate, with sharp edges and uniform colors. Fire clay bricks are light yellow or brown, silicon carbide bricks are black, white corundum bricks are white, chrome corundum bricks are purple-red and magnesia bricks are brown.
The lining of some small rotary kilns, such as lime rotary kilns, garbage rotary kilns, fluidized bed boilers, heating furnaces, etc., using precast bricks has a very good effect. The biggest feature of precast bricks is that we can make them according to different sizes of kiln linings. However, sintered refractory bricks cannot do this.
Refractory bricks have national standards and sizes and related index requirements. The porosity of fire resistance bricks is lower than that of precast bricks and the strength is better than that of precast bricks. Especially when used in areas with severe wear and erosion, the effect is obvious. However, we cannot use it as large-scale special parts in areas with too harsh conditions and locations.
The two types of high temperature refractory have their own advantages and disadvantages. They just have different effects in different situations, different temperatures and different parts of use. Therefore, when choosing, you still have to make it based on different situations.