Method for smelting ultra-low carbon steel

Abstract

The invention discloses a method for smelting ultra-low carbon steel. The method comprises a desulfurization procedure, a converter blowing procedure, an RH vacuum treatment procedure and a continuous casting procedure. After converter blowing, the temperature of tapping is 1680 DEG C-1700 DEG C, then ferroaluminum is added into liquid steel so that the liquid steel is subjected to preliminary deoxygenation; then the temperature is measured, oxygen activity is determined, and the liquid steel is fed with an aluminium wire according to a determined oxygen activity result, so that the oxygen activity is fine-tuned, and it is ensured that the oxygen activity is at 550 ppm-650 ppm; and the liquid steel meeting conditions enters the RH vacuum treatment procedure directly. A high target temperature of the converter tapping, with the partial ferroaluminum deoxygenation conducted after the converter tapping, enables the liquid steel to be kept at a high temperature level, and the temperature level meets the requirement for the temperature when the liquid steel enters the RH vacuum treatment procedure, so that an existing electric heating procedure is omitted; and the liquid steel can enter the RH vacuum treatment procedure directly, so that energy consumption in the steel making process is reduced greatly, and steel making efficiency is enhanced effectively after the heating procedure is omitted.

Description

technical field [0001] The invention relates to the technical field of steelmaking, and more specifically, relates to a method for smelting ultra-low carbon steel. Background technique [0002] Ultra-low carbon steel refers to steel with a carbon content below 0.01%. At present, the process of desulfurization-converter blowing-LF treatment-RH vacuum treatment-CC (continuous casting) is generally used to smelt ultra-low carbon steel. [0003] At present, in this process, the temperature of the molten steel after converter blowing is relatively low. Before entering the RH vacuum treatment furnace, it needs to be heated by electric heating in the ladle furnace, and then sent to the RH vacuum treatment furnace for decarburization. Deoxidation alloying. During the smelting process of this kind of process, the temperature loss when the converter is released is relatively large, and a large amount of electric energy is required to raise the temperature of the molten steel to the p...

AI Technical Summary

Problems solved by technology

During the smelting process of this kind of process, the temperature loss when the converter is released is relatively large, and a large amount of electric energy is required to raise the temperature of the molten steel to the processing requirements of the RH vacuum treatment furnace again, which not only consumes high energy, but also increases the smelting time. Reduce smelting efficiency