Low-carbon and low-silicon steel deoxidation process

Abstract

The invention relates to a low-carbon and low-silicon steel deoxidation process, comprising the following process flow: converter taping: tapping when the content of oxygen at the end point of the converter is over 500ppm; adding carbon powder at the beginning of the tapping for rough deoxidation, measured by the carbon dust of 0.15-0.25kgper ton of steel; adding aluminum iron for deoxidation alloying when the tapping is carried out to be 1 / 2 or 2 / 3, measured by the aluminum iron of 1.5-2.5kg / t steel; opening a steel ladle to an argon flushing station; supplementing aluminum iron: measuring the oxygen content of the steel ladle by using an oxygen probe, supplementing aluminum iron according to the measured oxygen content and adjusting the content of the oxygen of the steel ladle to be less than 50ppm; and flushing argon at the beginning of tapping at the flow of 300-400NL / min and adjusting the flow of bottom blowing argon gas to be 50-80NL / min when the steel ladle is opened to the argon flushing station for softly blowing argon. By using the carbon powder to deoxidize instead of the aluminum iron, the invention not only saves the cost of alloy, but also improves the purity of molten steel.

Description

technical field [0001] The invention belongs to deoxidation and its process method during steel tapping in the converter smelting production process, and in particular relates to a deoxidation process for low-carbon and low-silicon steel. Background technique [0002] The deoxidation operation in the converter smelting process is a key link in controlling the oxygen content in steel. The traditional deoxidation process uses silicon and aluminum in the alloy to react with oxygen in molten steel to form non-metallic compounds, which are then removed as much as possible by means of argon blowing, sedation, and refining. However, it is still inevitable that some non-metallic compounds will remain and form inclusions to pollute the molten steel, which is the main factor affecting the purity of steel and the quality of steel. For the smelting of SPHC and other low-carbon aluminum-killed steels, domestic manufacturers all adopt the process of tapping and adding aluminum to deoxidi...

AI Technical Summary

Problems solved by technology

[0003] The present invention aims to solve the problem that the traditional smelting and production of low-carbon steel deoxidation process adopts aluminum deoxidation, which not only consumes a large amount of aluminum alloy or metal aluminum ingots, but also forms deoxidation products that are difficult to remove in the subsequent treatment process, and a large amount of deoxidation products remain in the steel. It is easy to cause flocculation production accidents in water or cause serious surface quality problems of the final product, and provide a low-carbon and low-silicon steel deoxidation process that replaces aluminum and iron with carbon powder, which not only saves alloy costs, but also improves the purity of molten steel