Papers by Keyword: Steel Ingot

Abstract: Infrared radiometric long-waved systems are widely used in various industries as well as in research and development. This long-waved system is the perfect tool for quick diagnosis of the state of the equipment, easy defect detection, which is reflected by higher temperatures due to increased friction and wear. Infrared radiometric long-waved systems are used especially in civil engineering, electrical engineering, metallurgy and many other industries. They are also used to optimize and improve of the production processes. The series of measurements using the infrared radiometric long-waved system in steel plant were carried out due to prepared research project. Images of temperature fields of ladles with liquid steel, cooled exhaust knee of electric arc furnace and ingot mould were obtained during solidification of steel ingot. Information about the state of wear of the refractory lining of the ladle, exhaust knee can be gained from obtained images. The obtained results can be used for more accurate numerical simulations of the process of casting and solidification of steel ingots.

Abstract: The simulation of macrosegregation in a 2.45-ton steel ingot with the three-phase mixed columnar-equiaxed model was presented previously. The results showed an overestimation of the intensity of bottom negative segregation. The reason is due to the assumed globular morphology for the equiaxed crystal. Therefore, in this paper a simple approach is suggested to treat the dendritic morphology of equiaxed crystals. Three aspects are improved: the drag force between the moving equiaxed crystals and the surrounding melt, the mechanism of the columnar-to-equiaxed transition, the packing limit of the equiaxed crystals. The modified model is used to calculate the macrosegregation of the same ingot. It is found that the modified model predicts less severe negative segregation in the bottom equiaxed zone than the previous globular equiaxed model does, i.e. it agrees better to the experiment. The model considering simplified-dendritic morphology improves the calculation accuracy.

Abstract: Through establishing solidification-heat transfer mathematical model of the super heavy steel ingot, the temperature distribution at different moments in the solidification process of steel ingot has been simulated. Based on the simulated temperature field and the law of solute redistribution, the carbon macrosegregation in the solidification process has been calculated. The results show that, the complete solidification time of the 600T steel ingot is 68.34 hours, and positive segregation of carbon forms in the ingot head, and the concentration of carbon near the upper axis which is higher than 81 percent of the ingot’s height is over 2 times than the average value.

Abstract: The paper brings data about heat balance of the killed steel ingot head. The balance is obtained on basis of the temperature measurement in the system: ingot body - ingot head - ingot mould - insulating sleeves – radiation shield - ambient. The measurements were performed using model sys-tem (1:5) of the 20000 kg flat ingot. The balance shows that about 86% of the heat issued during solidification of the ingot head is transferred to the ingot mould through the insulating sleeves. In order to decrease this heat, insulating sleeves of low thermal conductivity are required, which should allow reducing dimensions of the ingot head and increasing the metal yield.