Process method for converter smelting of weathering resistant steel

Abstract

The invention discloses a process method for converter smelting of weathering resistant steel. The process comprises the following steps: 1) after smelting carbon steel by a converter, conveying steel slag treated by hot slag or drum slag as a slag auxiliary to an overhead bunker of the converter for later use, wherein the steel slag of the converter comprises the following chemical components in percentage by weight: 56% of CaO, 18% of SiO2, 0.3% of P2O5, 12% of TFe, 9% of MgO and 4.7% of other components; 2) using carbon-containing magnesium balls produced by the company Henglongxiang, wherein the magnesium balls comprise the following chemical components in percentage by weight: 15% of CaO, 12% of SiO2, 55% of MgO and 18% of C; 3) smelting by the converter according to a normal smelting program: namely, after adding molten iron steel scrap and before blowing by an oxygen lance, adding 60kg/ton steel of abandoned cold slag of the converter, and adding 3kg/ton steel of magnesium balls after decarburizing reaction to inhibit phosphorus in a molten bath from being oxidized into slag; and 4) before converter blowing end point, adding 5kg/ton steel of magnesium balls to press the slag, tapping after 3 minutes, and reducing phosphate in steel slag by using intermediate carbon by using the magnesium balls, so that phosphate enters molten steel.

Description

technical field [0001] The invention relates to a process method for smelting weathering steel in a converter. Background technique [0002] Phosphorus is soluble in ferrite, and has strong solid solution strengthening and cold hardening effects in steel. Adding it as an alloying element to low-alloy structural steel can improve its strength and atmospheric corrosion resistance of the steel, so it is a beneficial element for smelting weather-resistant steel . [0003] Literature search disclosure: (1) Wu Kang, Zheng Yi, Jian Jie, and Hong Jianguo stated in the paper "Production Practice of Smelting Phosphorus-Containing Weathering Steel by Improving Oxygen Supply Intensity" published in "Steelmaking" 2010, 26 (2). Average w(P) = 0.22% raw material smelting weathering steel" content. (2) Zhao Guoguang, Zuo Kanglin, and Zou Junsu published the paper "Smelting Weathering Steel SPA-H with Low-cost Converter at Meishan Iron and Steel" published in "Baosteel Technology" No. 2, 2...

AI Technical Summary

Problems solved by technology

[0004] From the above information, it can be known that most weathering steels smelted by converters currently adopt the process of smelting phosphorus-containing weathering steels without adding lime or adding less lime, but there is no mention of using converter steel slag as slagging material for smelting weathering steels. The literature also did not mention how to solve the problem of low thermal efficiency of the converter due to the intensified splash loss of metal materials caused by the decrease in alkalinity during the blowing process of the converter after reducing the amount of lime