Method for smelting ultra-low-carbon steel by using single-nozzle refining furnace

Abstract

The invention relates to a smelting method of ultra-low-carbon steel, which is an operating method for decarburizing by using a single-nozzle refining furnace. The invention is a smelting method for smelting ultra-low-carbon steel by using the single-nozzle refining furnace. The method is used for smelting the ultra-low-carbon steel with C of being less than or equal to 20ppm, and adjusts the inserting depth of a single-nozzle furnace dipping pipe, lance position of an oxygen lance, vacuum degree, oxygen supplying flow and eccentric bottom-blown argon of a steel ladle to stir molten steel under the vacuum condition by controlling the initial conditions of the thickness of a tapping slag layer, the temperature of arrived molten steel, the content of arrived carbon and the like so as to achieve the purpose of decarburization. The method has the following advantages that: 1. the treatment time of the molten steel is short, the refractory material consumption is low, and the scaffolding of the dipping pipe is little; and 2. the smelting time is short, the splashing is little, the consumption of sealing rings is less, the corrosion of the steel ladle is not serious, the cost is low and the operation is simple.

Description

Technical field

[0001] The invention relates to a method for smelting ultra-low carbon steel, which is an operation method for decarburizing using a single nozzle refining furnace. Background technique

[0002] The current large-scale production of ultra-low carbon steel is mainly RH and VOD smelting methods.

[0003] ① RH (developed by Ruhrstahl and Heraeus by vacuum cycle degassing) adopts a double-nozzle dip tube, the molten steel in the ladle is inserted into the dip tube and then vacuumed, oxygen is supplied under vacuum and argon is blown from the side of the tube to smelt ultra-low carbon steel. Due to the use of the double-suction nozzle type dip tube in this method, the small circulating flow rate causes the problems of long treatment time of molten steel, serious nodulation of the dip tube, and short life of the dip tube.

[0004] ②VOD (vacuum oxygen decarbruization of ladle in a vacuum tank) adopts a tank vacuum environment, top blowing oxygen, low argon or nitrogen blow...