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The effect of cold-ramming hearth mix density on the annealed mix dynamic elastic modulus is investigated. It is shown that analysis of the elasticity modulus curves makes it possible to determine the area of optimum hearth mix compaction within which it has a mechanical property level comparable to hearth blocks.

In this study, to develop a ramming mix, the D-optimal mixture design method was used, which makes it possible to achieve in the new type of ramming mix the optimal concentration of carbonaceous raw materials – silicon carbide, graphite, pitch. Using the expert-design software and a special preparation methodology, 16 samples of varying compositions were prepared, and their physical properties, such as dried and fired strength, were evaluated. In order to determine the optimal formulation, 12 models were studied. The model with the highest percentage of desired properties at 78.5% contained 11.7 wt.% silicon carbide, 2.6 wt.% graphite, and 5.7 wt.% pitch. Thus, this is the optimal composition of a ramming mix of the MgO–SiO2–SiC–C system for a blast furnace pig iron runner.

The prospects of using bauxite-base HCBS in the production of high-quality ramming mixtures for lining blast furnace spouts are considered. A system of Chinese bauxite (filler) and bauxite HCBS (binder) is shown to give a ramming mixture with a porosity of 18 – 22% and σc of 120 MPa. The effect of some process factors on the properties of the new refractory material is considered. The life of the mixture in the main hearth spout is shown to be 70 – 90 thousand tons cast iron before the first repair at a consumption of 0.53 – 0.63 kg mixture per one ton cast iron. The processes that occur in the interaction between the material and blast furnace slags of various chemical compositions is considered. The characteristics of the developed mixture are compared with those of the standard ones.

A technology is developed for the production of corundum-based ramming mix compositions, in which the fused-corundum component is partly replaced by commercial alumina of GK grade bound with an aqueous orthophosphoric acid solution of reduced density. The modified ramming mix compositions are produced on a commercial scale by the Experimental Plant of the UkrNIIO Joint-Stock Company.

The composition of a plastic ramming mixture for lining annular burners of machines for centrifugal die blowing (CDB) developed for the Chudovskii glass plant is described. Pilot plastic ramming mixtures supplied by UkrNIIO have been used to line three circular burners and exhibited an endurance at a level of international standards.

A laboratory study aimed at replacing expensive chamotte from Chinese bauxites used in a ramming mixture by disthene-sillimanite concentrate is described. It is shown that partial replacement of the chamotte by disthene-sillimanite concentrate can give the required high-alumina ramming mixture.