Gui Fang Zhang

Effect on Position of Electromagnetic Stirring on Inclusion Behaviors in Billet

A considerable number of research works have been carried out to study the effects of electric current and frequency of Electromagnetic Stirring (EMS) on the quality of cast steels, but there are only a few studies available addressing the effects of EMS location on inclusion removal and steel cleanliness An ideal position of EMS will improve inclusion floatation and separation from liquid steel. However, inappropriate installation will lead to the entrapment of the slag into liquid steel, and impact the quality of cast billet. The current applied for these plant trials was 300A at a frequency of 3Hz,positions form axial centers of EMS to the top of the mold were 450mm, 510mm and 690mm respectively . 130 billets of medium carbon steel were produced and samples were taken for spectral analysis to study the effects of installation location of EMS on steel cleanliness. The experimental results show that the optimum position of EMS should be placed 510mm from the top end of the copper mold when the electrical current is 300A at frequency of 3 Hz. The three parameters of placement of EMS in paper were obtained from the simulation results, and this paper focused mainly on the effect EMS position on inclusion behaviors in billet.

Calculation Model of Torpedo Ladle Number

In order to predict scientific and reasonable torpedo ladle number and optimize torpedo ladle scheduling, this article analyzed operation process and turnover cycle of torpedo ladle in K steel plant as the research object. The relationship between blast furnace supply and continuous caster demand is analyzed. Based on relationship between supply and demand, the calculation model of torpedo ladle number is put forward under the conditions of blast furnace supply greater than, less than, and equal to the continuous caster demand. The control model can calculate the number of normal ladle and saving ladle and casting ladle. Satisfactory effects are obtained after applying the calculation model in production. The torpedo ladle number of different relationships between supply and demand can decrease. The research results supplies new methods for optimization and control of ironmaking and steelmaking interface system. The research methods enrich the theory of integration and optimization of metallurgy process system.

Research Status of Numerical Simulation on LF Furnace Refining Ladle

The research status of physical simulation on LF furnace refining ladle is introduced in this paper.Since 1970, the research on the gas-liquid two-phase region has begun. The ladle of blowing argon can be roughly divided into three important flow region has been introduced. Two-phase region, the top horizontal flow zone and recirculation zone exists in the ladle.The establishment of physical model should include similarity principle and flow field measurement technique

The Introduction of the LF Refining Function and Process

The process of LF Refining is introduced in this paper.The LF method is a ladle without vacuum equipment can arc refining method.Because the LF ladle furnace has the advantages of simple equipment, low investment cost, flexible operation and excellent refined effect, are widely used and developed in many countries.The argon is blown from the bottom of the ladle, and molten steel is heated by the graphite electrode, so the purpose of refiningis achieved. The argon stirring can accelerate the chemical reaction between slag and steel.LF refining function includes reductive atmosphere, submerged arc heating, argon stirring and white slag refining.

Argon Blowing Technology Using in the LF Refining

The process of LF Refining is introduced in this paper. Because the LF ladle furnace has the advantages are widely used and developed in many companies. The argon is blown into the ladle, so the purpose of refining is achieved. The argon stirring can accelerate the chemical reaction between slag and steel. In the circulation process, large inclusion and deoxidation product in the lower region transfer into the slag. The material transfer between steel and slag can be accelerated. At the same time, argon stirring can make molten steel composition and temperature uniformity. Thus, the ladle of blowing argon can be roughly divided into three important flow region has been introduced. Two-phase region, the top horizontal flow zone and recirculation zone exists in the ladle.

The Introduction of the Chemical Composition in IF Steel Control

The background,development status and chemical composition controls technologies of IF steel smelting was introduced. In China, IF steel production has reached a certain scale, but is still in the primary stage of development.Liquid steel composition characteristics of IF steel is ultra-low carbon and nitrogen, micro alloying and pure steel. The automobile panel with defect free surface is produced, that must be accurate control of IF steel in carbon, nitrogen and other elements.According to the operating state, IF Steel process characteristics and chemical composition controls technologies weresummarized.

Control Model of Steel Ladle Base on Overlap Time among the Different Casts

Steel ladle is the indispensable vessel of transporting and refining molten steel. In order to realize efficient control of steel ladle and optimize the production organization of steelworks, the operational control model of steel ladles should be proposed. Based on steel ladles of Z steelwork as the research object, operation mode and turnover cycle of steel ladle were analyzed. Through drawing out steel ladle Gantt chart of single continuous caster and analyzing operation characteristics of steel ladle, calculation model of turnover number and rotation ratio of single continuous caster was put forward. Through drawing out steel ladle turnover Gantt chart of 3 continuous casters and analyzing mixed use characteristics of cast overlap time greater than, less than, and in between steel ladle turnover cycle of 3 continuous casters, the operational control model of steel ladles was put forward. Researches show that the model can effectively reduce amount of steel ladle turnover number and raise steel ladle rotation ratio when casting heat number of CC is less than steel ladle turnover number during the overlap time.

Comparison of COREX and COSRI Process Technology Development

COREX and COSRI smelting reduction iron-making process could directly use coal as reductant. So it is necessary to contrast the development and technology of two kinds smelting reduction iron-making process. Due to lack of funds, COSRI smelting reduction iron-making process has not been fully developed. And the COREX has completed the transformation to the industrial production. But on the whole, COSRI has good prospects for development as COREX.

The Evolution of Non-Metallic Inclusions in IF Steel

At present, Chinas IF steel production has get a certain scale. But IF steel production is still in the primary stage of development. Therefore, the process control of inclusions in IF steel have become a pressing matter of the moment. This has important theoretical value and practical significance for further development of IF steel production in China. According to the size, the inclusions can be divided into super micro inclusions, micro inclusions and micro inclusions in the steel. According to the deformation capacity, inclusions can be divided into plastic inclusions, semi plastic inclusion and brittle inclusion.

Experiments on Effect of Red Mud-Based Slag on Distribution of Sulfur in Liquid Iron

Preliminary research has shown that red mud is a viable option to be used as a fluxing agent in the steelmaking process, as it is able to achieve similar results as fluxes currently used in steel refining. This research focused on how red mud can be used as a flux for refining steel. Desulfurization was conducted with aluminum additions and temperature variations. The results showed that experiments utilized waste residues from the aluminum industry as refining flux for steel refining; more than 95% sulfur reduction was achieved; increasing temperature and aluminum content can improve desulfurization.