Smelting method of phosphorus-containing steel in top-bottom combined blowing converter

Abstract

The invention relates to a method for smelting phosphorus-containing steel in a top-bottom combined blowing converter, comprising the following steps: 1) the phosphorus content of molten iron is between 0.08% and 0.12%, the oxygen supply pressure is 1-1.05Mpa, and the oxygen supply intensity is 3.5-3.8m3 / (t.min); 2) Within 1 to 3 minutes of blowing, add activated lime and lightly burned dolomite; add iron-containing material carbon balls after 1 minute; 3) The position of the oxygen lance adopts high-low-low position , bottom blowing adopts N / Ar automatic switching mode; 4) Bottom blowing nitrogen is used in the early and middle stages of reblowing medium, and bottom blowing argon mode is used for 1 to 2 minutes before carbon pulling in the later stage of blowing; the end temperature of blowing is controlled at 1660 ° C ~ 1680 ℃, the end-point carbon is controlled at 0.04-0.06%; the end-point phosphorus content is controlled between 0.05%-0.075%; 5) the phosphorus content of the finished product is between 0.06%-0.09%. Compared with the prior art, the beneficial effects of the present invention are: by improving the smelting process of phosphorus-containing steel in the top-bottom combined blowing converter, the blowing time can be shortened, and the rapid decarburization and phosphorus conservation of the combined blowing converter can be realized; the oxygen utilization rate can be improved, The purpose of shortening the smelting time and reducing the cost.

Description

technical field [0001] The invention relates to the technical field of converter steelmaking technology, in particular to a method for smelting phosphorus-containing steel in a top-bottom combined blowing converter. Background technique [0002] Phosphorus-containing steel refers to steel with a finished phosphorus content in the range of 0.06% to 0.09%. According to the normal smelting process, the cost of adding flux and alloy during smelting is high, the oxygen utilization rate is low, and the blowing time is long. Contents of the invention [0003] The invention overcomes the deficiencies of the prior art and provides a method for smelting phosphorus-containing steel in a top-bottom combined blowing converter. By adjusting the process parameters, the amount of flux added is reduced, the cost of flux and alloy input is reduced, the smelting cycle is shortened, and the utilization rate of oxygen is improved. the goal of. [0004] In order to achieve the above object, th...

AI Technical Summary

Problems solved by technology

[0002] Phosphorus-containing steel refers to steel with a phosphorus content in the range of 0.06% to 0.09%. According to the normal smelting process, the cost of adding flux and alloy during smelting is high, the oxygen utilization rate is low, and the blowing time is long.