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The substance and mineral composition of talcomagnesites and their firing behavior are investigated. Laboratory and industrial tests show their prospects for the refractory industry as a magnesia-silicate component. The main parameters of the production of forsterite refractories from talcomagnesite of the Pravdinskoe Deposit are similar to those of dunite articles. The properties of the articles meet the requirements of GOST 14832-79.

Laboratory and production investigations with production and testing of experimental lots of magnesia-type ladle parts have shown the promise of use in the slag belt of ladles with ladle treatment of the steel of chromite-periclase-forsterite and periclase-spinellide (with synthesized magnesioalumina spinel) parts.

Ladle and roof parts with use of fused spinel from bauxite and periclase were produced on a semiproduction basis. It was shown that the parts have good service properties. Service tests showed the effectiveness of periclase-spinellide type parts.

Experimental production investigations have established the prospects of use of forsterite-containing refractories for lining steel-teeming ladles. Tests in the 350-ton ladles of Azov Steel Combine Converter Shop and the 310-ton ladles of Kommunarsk Metallurgical Combine Open Hearth Shop showed that the life of these refractories is similar to that of periclase—chromite ones and exceeds that of aluminosilicate ones.

Production tests have been made of a dolomite-dunite mixture in the 250–650 ton open hearths of the Makeevka, Krivoi Rog, and Kommunarsk Metallurgical Combines in patching the rear walls, banks, and front bulkheads. The tests established no differences in use of the mixture in comparison with fired dolomite and no differences were established in the process.

The service conditions of tubes for protection of the stream of metal from secondary oxidation in No. 2 Electric Melt Shop of Oskol Electrometallurgical Combine have been studied, a method for production of periclase-carbon tubes has been developed, and an experimental lot has been prepared at Novomoskovsk Refractory Plant. The tests under conditions of No. 2 Electric Melt Shop of Oskol Electrometallurgical Combine showed the promise of use of periclase-carbon materials in production of tubes for protection of the stream of metal from secondary oxidation.

It was established that the kinetics of the burning-up process of the carbonaceous substance has an exponential nature and in semilogarithmic coordinates, it can be described by a straight line relationship log C=α+tan ατ.

It is possible to make fireclay steel plugs with a high spalling resistance by adding oil to the nonplastic part of the batch, using the semidry method in production conditions.

The Chasov Yar Refractory Products Combine, together with the Khar'kov Polytechnical Institute, manufactured a large industrial batch of blast-furnace brick with addition of surface-active substances to the mixture. A significant improvement in the quality of the brick was achieved.

When a number of zirconia mixtures for the manufacture of parts were tested, the best results were shown by those made from mixtures containing 45 – 50% fraction 1.5 – 0. 5 mm and 55 – 60% finer than 0. 088 mm.

The method developed and introduced at the Chasov-Yar Combine permits bulk density and density differences in freshly tamped and fired glass tank blocks to be measured without destroying them, with an accuracy corresponding to the requirements of GOST.

During the blending of bodies, containing a mixture of chamotte and clay ground in combination in tube mills, on mixers of four types used at the Chasov Yar Combine, the best pressed specimens were obtained when the bodies were worked on the centrifugal runnermills 115 M with normal rollers. Therefore, we do not recommend the removal from these mixers of factory-made rollers, although the mixers require improvement.

Silicon carbide rammed bodies are suitable for lining the combustion zones of high-pressure cyclone burners of steam boilers. The life of the silicon carbide body depends on the heat resistance of the supporting joints (the hooks).

Dense semiacid products based on low-fired chamotte can be obtained by adding 15–30% quartz sand to the batch. The articles need to be fired at 1260±30–40°C. Firing at temperatures above 1300° and below 1230 even by 20–40° reduces the apparent density and after-expansion of the products.

The compound proportioning device designed by the All-Union Institute of Refractories from an aluminous nozzle containing 80–82% alumina with a porosity of 18–23% and a corundum insert containing 97% alumina with a porosity of not more than 18% satisfies the requirements of continuous casting of low-carbon rimmed steel of the type 05–08KP. Investigations led to the determination of a range of refractories for steel casting and intermediate ladles permitting satisfactory casting in continuous casting plant of low carbon rimmed steel of the type 05–08KP from 140-ton ladles in four shanks with a casting time of about 1.5 h.

Incorporating small additions of talc — magnesite and surface-active agents in preparing kaolinitic chamotte and products based on it would reduce the water absorption of the chamotte and the porosity of the goods, and increase their compressive strength.

The injection burners ensure jet combustion of the gas with the generation of an oxidizing atmosphere in the tunnel kiln. The firing of dense ladle brick and brick for blast furnaces in such kilns must last for 50–60 h.