Spinel and carbide formation in oxide-carbon refractories for steel-casting ladles

In the converter shop at OAO Nizhnetagil’skii Metallurgicheskii Kombinat (NTMK), the steel-casting ladle is lined with oxide-carbon refractories. The aggressiveness of slags toward the refractory lining is explained. The composition of the linings is studied, along with the processes within the refractories at high temperatures. The basic requirements on refractory components supplied to OAO NTMK are formulated. The life of casting-ladle linings in the converter shop is increased.     

平炉改转炉后除尘状况的分析及改进

对武钢一炼钢厂“平改转”后除尘系统存在的问题进行分析。阐述了“平改转”后除尘的现状,研究了除尘工艺设计中的缺陷,分析了在生产过程中所存在的问题,提出了解决这些缺陷及问题的措施和对策。     

Development of the continuous casting of steel at the Chelyabinsk Metallurgical Combine

In 2007, the electric steelmaking shop at the Chelyabinsk Metallurgical Combine operated with two continuous slab casters made by Uralmash, while the oxygen converter shop had two continuous section casters made by the Danieli company. It was decided that the two Uralmash casters will be replaced by a single Danieli caster. The shop has also mastered a technology for casting corrosion-resistant, reinforcement-grade, pseudo-rimming, and low-and medium-carbon steels. Plans call for further expansion of the range of grades of steel that can be cast.     

Improving the durability and reliability of vacuum-chamber linings

Several practical methods of improving the durability of vacuum-chamber linings in the converter shop at OAO Nizhnetagil’skii Metallurgicheskii Kombinat are considered.     

Development of continuous casting at OAO MMK

The introduction of continuous casting at OAO MMK was a historic event, marking the end of uneconomical chill casting. Thanks to the introduction of continuous casting in the oxygen-converter shop, improvement in casting-machine design, and expansion of the range of steel that can be cast, unique casting characteristics have been attained: high productivity (more than 10 million t/yr), long casting runs (up to 208 melts), infrequent accidents, low rejection rates of the steel, and high quality of the continuous-cast slabs. The introduction of continuous casting in the converter shop provided a stimulus to the reconstruction of the open-hearth shop as an electrosmelting shop and the installation there of two bar-casting machines and one slab-casting machine.     

Use of 140-ton ladles to transport liquid pig iron

At the end of 2003, the Chelyabinsk Metallurgical Combine began to use 140-ton ladles instead of 100-ton ladles to transport liquid pig iron to its oxygen converter shop. The larger ladles comprised roughly 55% of the ladle stock in 2006 and transported 65% of the pig iron to the shop. Use of the 140-ton ladles has markedly improved adherence to the tapping schedule and sharply reduced the number of inadequately processed blast-furnace heats. It has also increased the temperature of the pig iron in the converter shop due to the smaller heat losses in the larger ladles.     

Extending the lining life in circulatory vacuum units at OAO EVRAZ NTMK

Practical methods for extending the life of submersible tubes in vacuum chambers are considered. The structure of periclase-chromite components is studied. Refractories corresponding to optimal vacuum-chamber operation in the converter shop at OAO EVRAZ NTMK are selected.     

Use of electric-arc heating of steel in oxygen-converter production

The oxygen-converter shop of the Magnitogorsk Metallurgical Combine has introduced an additional unit for the electric-arc heating of steel. This article presents the main results that have been obtained in making converter steel with the use of electric-arc heating during out-of-furnace treatments of the steel.     

Dynamic monitoring of slag oxidation and thickness in the ladle-furnace unit

Methods are proposed for ongoing monitoring of the slag oxidation and the depth of the electrical arcs in slag at the converter shop of OAO EVRAZ NTMK. Such monitoring is expected to increase the rate of metal heating, reduce the ferroalloy and power consumption, and increase the lining life in casting ladles.     

高度补偿器在宣钢天车称量系统中的应用

宣钢二钢轧厂150 t炉区天车称量系统,承担着铁水复磅和转炉铁水装入量的称量及钢水产出量的计量任务。由于二级数据采集要求精度高,自动炼钢模型必须建立准确的钢水、铁水称量数据,才能进一步提高产品的质量和性能。通过在天车称量系统增设高度补偿器,对天车称量系统进行设计改造,提高了计量精度,克服了行车电子秤称重过程中由于钢丝绳质量变化对称重结果的影响。