A resource-saving technology for manufacturing unfired articles for bottom casting of steel

A resource-saving technology for producing unfired chamotte refractories for bottom casting of steel is described. The effect of the amount and type of H3PO4, the method of its incorporation in the charge, the moisture content of the mixture, the pressing pressure, and the heat treatment regime on the properties (apparent density; open porosity; water resistance; compressive strength) of laboratory specimens was established. Industrial tests were performed on an experimental batch of unfired bottom pouring tubes produced by the suggested technology. They were found to be suitable for bottom casting of steel. 4 refs.