High-alumina refractory castables, like other refractory castables, are composed of high-quality refractory aggregates, powders, binders, and admixtures. During the construction process, we repeatedly emphasize that the amount of water must be strictly required. The most critical factor for the amount of water added and the construction quality of high-aluminum castables is the decisive factor for whether the castables can exert the performance of the applied products.
Take high alumina refractory castable as an example, high alumina bauxite aggregate is about 65~70%, high alumina cement is 7~10%, silica fume and alumina powder is between 5~8, bauxite fine powder is 15 Between ~24%, the water reducing agent is about 0.2%; the last is to decide the use of accelerator and retarder according to the ratio. For castables configured like this, the water consumption required for construction is generally about 30% (different construction conditions, water consumption is also different), this is very important, and we must not ignore it.
If more water is added during the construction of refractory castables, the materials will get closer and closer to the fluid, which will generate greater lateral pressure on the bottom of the side mold; even for castables like high-aluminum refractory castables, the state of adding more water Under circumstances, it will cause too much water on the surface of the castable. Although it looks more pleasing to the eye, it will greatly reduce the density and strength of the high-alumina cement castable, and the requirements will be greatly increased during drying. , It is likely to cause the high-alumina cement refractory castable to accidentally collapse or produce many cracks, which will affect the service life of the castable. In the case of high alumina cement refractory castable with little water, it will cause the castable material to fail to flow normally and achieve a dense filling, air bubbles cannot come out, and can not form a tight accumulation, which promotes the phenomenon of poor construction of the castable.
The amount of water used for high-aluminum refractory castables will directly affect the service life and performance of the castable. Therefore, when mixing high-alumina refractory castables, attention must be paid to the water consumption.