OAO Krasnogorovka Refractory Plant innovative technology

Abstract

The Krasnogorovka Refractory Plant is one of the leading enterprises of the refractory industry with more than 100 years of experience of producing high quality refractory materials. The plant was founded in 1899 as the Societe Franco-Russe de Krasnogorofka as a plant for producing quartz and silica bricks, ceramic fireplaces and bottles. Before 1905 the plant operated seasonally. Currently the plant is one of the largest enterprises in the area of refractories. The number of production personnel is 1353. The annual volume of production in 2007 was 125 thousand tons. The plant produces dinas, aluminosilicate refractories, and also unmolded materials of silica and aluminosilicate compositions. In view of the reduction in demand for traditional forms of refractories the plant has renewed its production range. In 2003 an innovation center was created whose efforts were directed towards expansion of the product range and an improvement in quality. Considering the increased specifications for contemporary refractory materials the specialists of the center started independently to develop and assimilate production technology for starting mixes for filling the pouring channel of steel-pouring ladle. It would be necessary to offer the user a competitive product with properties not surpassed by overseas analogs. Several compositions of mixtures were tested under laboratory conditions with different feedstock materials and grain size composition undergoing tests at high temperature. After analyzing test results samples of mixtures were prepared for testing under industrial conditions in the “upstream pouring” of the Il’ich OAO MMK converter workshop. Mixtures were tested during pouring of rimming and killed grades of steel; mixtures similar in composition to the starting mixes were tested during pouring steel in a CBCM. Metal was in the ladles from delivery to pouring in a CBCM from 1.10 to 1.36 h. All ladles were opened spontaneously without using oxygen pipes, but due to difficulties that arise during charging mixes into the ladle pouring channel the composition of the starting mix was modified; a new test-industrial batch was prepared taking account of the requirements of metallurgists. Mixtures were tested in the OAO MMK im Il’icha converter workshop both in the CBCM and in the “upstream pouring” with delivery of different grades of steel; the duration of metal in the ladle from the start of delivery to the start of pouring was 0.37 to 2.26 h. The test starting mix providing uniform opening capacity for the delivery channel and correspondingly a uniform stream, and least metal splashing. The opening capacity of the slide gate channel without using oxygen pipes was 95.6%. By achieving good results for opening capacity, the OAO Krasnogorovka Refractory Plant proposed using their starting mixes for charging the channel of the ladle nozzle during pouring steel in various metallurgical enterprises of Russia and the Ukraine. Channel opening capacity for the slide gate using starting mixes in different enterprises was: 97.8% in OAO Alchevsk Metallurgical Combine, 95.8% in OAO Novolipetsk Metallurgical Combine, 92.5% in Dzerzhinskii Dneprovsk Metallurgical Combine, 100% in OAO Mechel, 100% in OAO Izhstal’. In OAO Izhstal’ the starting mix was tested in slide gates of a 30-ton ladle of the furnace-ladle unit. Structural low-alloy steel was processed in the ladles. The pouring temperature was 1560 – 1580°C. On opening the slide gate the mix spontaneously ran out of the pouring nozzle channel in all melts. The results of industrial tests of starting mixes in metallurgical enterprises of Russia and the Ukraine both in the “upstream pouring” and in a CBCM showed that the mix has high operating characteristics and it properties it is no worse than overseas analogs. Use of a starting mix in OAO KrOZ for charging the steel-pouring channel almost entirely excluded washing away of the pouring opening of a steel-pouring ladle before metal delivery. OAO KrOZ independently developed and introduced technology for competitive refractory production not manufactured by other refractory enterprises in the Ukraine. In view of this the question arose of developing normative and technical documentation for starting mixes. The enterprise Refractories and Industrial Ceramics Vol. 50, No. 1, 2009