Design of bauxite-based low-cement pumpable castables: a rheological approach

The growing demand for pumping of refractory castables, as a high efficient placing technique, has stimulated the development of compositions with specific rheological properties. In this work, a new type of rheometer has been used to measure the rheological behaviour and to predict the pumpability of bauxite-based low-cement castables. This overcomes the shortages of traditional techniques based on either flow measurements or working with the matrix portion of castable. The parameters which strongly influence the rheological properties and pumpability of bauxite-based low-cement castable such as particle size distribution, ratios of coarse to matrix and water to matrix, water addition and time have been studied. It has been found that the optimal flow resistance and torque viscosity are two important properties to be taken into consideration while designing a castable.