Schungite for improving the durability of the refractory lining in blast furnace runners

A technology for manufacturing refractory ramming mixtures for the runners of blast furnaces is proposed based on the use of schungite in place of the conventional coke. The resistance of the lining to attack by molten metal and slag and its service life improved significantly using silicon carbide produced from schungite. __________ Translated from Novye Ogneupory, No. 5, pp. 29–31, May, 2006.     

Service of the magnesia-spinellide lining of a melting furnace roof

Conclusions On the basis of a study of the magnesia-spinellide roof of a melting furnace it was established that the refractory consists of four zones, the least changed, the working, the zone of contact with the lining slag, and in the lining slag. A nonuniform distribution of the components in specimens of lining slag taken from different portions of the roof was observed.The lining slag and the zone of contact with the lining slag consist of crystals of picrochromite, ferrite, and magnesioferrite, between which there is located a silicate binder including forsterite, hedenbergite, and the impurity phases bunsenite, hematite, and magnetite. The working zone consists of chromite, picrochromite, monticellite, and the introduced melting products copper, chalcosite, and cuprite.On the basis of analysis of the data on failure of refractories as the result of chemical interaction with the melting products, penetration of the low-melting components, and thermomechanical cracking at the boundaries of the zones it was established that one of the methods of protection of the roof is cooling.Translated from Ogneupory, No. 2, pp. 51–55, February, 1989.     

Effects of mixture composition on the lining stability of a crucible induction furnace

Research results are reported on the effects of components on the resistance of acid lining for the crucible induction furnace. To raise the lining resistance, one needs to eliminate components that react with the silica crucible. The extent of silicon reduction from the lining is dependent on the heating of the metal and the contents of carbon and silicon in the liquid. Increasing the carbon content and reducing the silicon concentration in the metal favor wear on the crucible. The slag components most actively influencing the resistance of the lining are magnesium and calcium oxides, which are produced on modifying cast iron, ferrous oxide, and manganese on account of reduction in the viscosity of the slag, increase in its wetting power, and penetration into the pores and unevenness in the walls of the crucible. Translated from Novye Ogneupory, No. 5, pp. 41–43, May, 2008.     

Technology of repair and ways of improving the durability of the lining of a vacuum degassing chamber

Atechnology for repair of the lining of a vacuum degassing chamber is presented.Ways of improving the service life of submersible snorkels by hot repair and strengthening the metallic structure of snorkels are proposed. __________ Translated from Novye Ogneupory, No. 3, pp. 10–11, March, 2006.