Clay binder is one of the main materials of clay refractory castable and an important component of matrix. Therefore, the variety and dosage of clay binder have important influence on its properties. There are many kinds of clay, and the clay in each place has different properties due to different mineral sites. In short, if the choice of clay binder is proper, the refractory castable with good performance can be prepared.
The dosage of clay binder is 9%~12%. Because the combined clay contains more low-melting point substances, the fire resistance performance is poor, in order to meet the technical requirements for the preparation of clay castable, it should be reduced as much as possible. The effect of the type and amount of coagulant on the properties of clay refractory castable. For the compressive strength at normal temperature and 1400℃, the effect of ca-70 cement is better than that of ca-50 cement, but the cost increases greatly. With the increase of the dosage of coagulant, the compressive strength of normal temperature increases continuously, while the compressive strength of 1400℃ decreases continuously.
In the clay refractory castable, refractory aggregate plays the role of skeleton and is an important part of it, accounting for 60%~70% of the total material. Refractory aggregate varieties according to the content of Al2O3 as the data, with the increase of Al2O3 content, high temperature compressive strength, softening temperature under load starting point is also increased, softening temperature under load are more than 1520℃, grade iii alumina clinker aggregate slightly higher. Therefore, grade 3 bauxite clinker is widely used as refractory aggregate for common clay refractory castable, and good results have been obtained.
The grading of refractory aggregate used for clay castables, the variety and fineness of refractory powder, water consumption and construction conditions, etc., also have certain influence on its performance ring, and the basic similar to the cement refractory castable, no need to repeat; There are many kinds of dispersants, through screening, sodium tripolyphosphate is widely used, and good results have been obtained dispersion effect.