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 andthe operation is simple.

Description

technical field

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

[0002] At present, the methods of large-scale production of ultra-low carbon steel are mainly RH and VOD smelting methods.

[0003] ① RH (developed by Ruhrstahl and Heraeus by vacuum circulation degassing method) adopts a double-nozzle type dipping tube, the molten steel in the ladle is inserted into the dipping tube and then vacuumed, and the method of oxygen supply under vacuum and argon supply by side blowing on the tube wall is used to smelt ultra-low carbon steel. Due to the adoption of double-suction-nozzle type dipping tubes in this method, the small circulating flow rate causes the problems of long processing time of molten steel, serious nodulation of dipping tubes, and short service life of dipping tube refractory materials.

[0004] ②VOD (vacuum oxygen decarburizat...