The growing demand for automatically transported refractory castables has stimulated the use of pumpable castables, which are usually specified as high fluidity compositions. However, this specification cannot be accepted as complete, since systematic studies are not commonly observed in the literature. Furthermore, the traditional techniques for rheological evaluation, which are based on flow measurements, cannot simulate the flow conditions of castables inside transporting pipes. Therefore, this work describes a new technique for the rheological characterization of pumpable castables, which is based on a rheometer for refractory castables combined with a device that simulates the flow conditions during the materials transportation. In addition, castables with distinct particle size distributions were rheologically evaluated based on this new technique. The results proved the high efficiency of this new method of rheological characterization, and the castable based on Andreasen's model, formulated using the distribution coefficient q = 0.26, was found to be the most suitable one for pumping.
castable; pumping; rheometer; refractory
