Yaroslavl State Technical University, Yaroslavl, Russia:

V. A. Ivanova, Dr. Eng., Associate Prof., Director of the Institute of Engineering and Machinery Manufacturing, e-mail: ivanova-waleriya@mail.ru
E. O. Pobegalova, Cand. Eng., Acting Head of the Dept. of Technology of Materials, Standardization and Metrology, e-mail: pobegalovaeo@gmail.com

The authors developed a methodology for assessing the cupola coke quality level quality. It based on the selection of indicators and test methods for assessing quality characteristics taking into account the life cycle processes. The article concerns with the quality properties of cupola coke. The parameters are the quantitative expression of the coke properties. However, the same cupola coke properties can be characterized by several parameters derived from different test conditions. Every stage of the life cycle should have parameters for assessing the quality of the cupola coke. The test conditions for determining the values should correspond to the conditions of stage of the life cycle. Once the value of the parameter is determined, the property it characterizes is assigned a quality level from 2 to 5. We assessed the aggregate quality level of cupola coke by a formula. Every property in it has a weighting coefficient. The weighting coefficients depend on the requirements of the iron to be smelted. We tested the methodology at stages "Iron Smelting" and "Application". The quality level value for the selected batch of cupola coke is 3.6, which corresponds to satisfactory quality. Thus, the proposed methodology for assessing the quality level of coke will determine the impact of the life cycle stages on its quality. It allows objectively assess the quality of coke using a flexible system of quality indicators, depending on the processes at a particular stage of the life cycle. Also it will predict the quality of coke during the changes in values of quality indicators.

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